Table 1 to Subpart A of Part 60 - Detection Sensitivity Levels (grams per hour)
40:7.0.1.1.1.1.1.20.1 :
Table 1 to Subpart A of Part 60 - Detection Sensitivity Levels
(grams per hour)
Monitoring frequency per
subpart a
Detection sensitivity
level
Bi-Monthly
60
Semi-Quarterly
85
Monthly
100
a When this alternative work
practice is used to identify leaking equipment, the owner or
operator must choose one of the monitoring frequencies listed in
this table in lieu of the monitoring frequency specified in the
applicable subpart. Bi-monthly means every other month.
Semi-quarterly means twice per quarter. Monthly means once per
month.
[73 FR 78211, Dec. 22, 2008]
Table 1 to Subpart Cb of Part 60 - Nitrogen Oxides Guidelines for Designated Facilities
40:7.0.1.1.1.6.1.11.2 :
Table 1 to Subpart Cb of Part 60 - Nitrogen Oxides Guidelines for
Designated Facilities
Municipal waste combustor
technology
Before April 28, 2009,
nitrogen oxides emission limit
(parts per million by volume) a
On and after April 28,
2009,
nitrogen oxides emission limit
(parts per million by volume) a
Mass burn
waterwall
205
205.
Mass burn rotary
waterwall
250
210.
Refuse-derived
fuel combustor
250
250.
Fluidized bed
combustor
180
180.
Mass burn
refractory combustors
No limit
No limit.
a Corrected to 7 percent oxygen,
dry basis.
[71 FR 27334, May 10, 2006]
Table 2 to Subpart Cb of Part 60 - Nitrogen Oxides Limits for Existing Designated Facilities Included in an Emissions Averaging Plan at a Municipal Waste Combustor Plant b
40:7.0.1.1.1.6.1.11.3 :
Table 2 to Subpart Cb of Part 60 - Nitrogen Oxides Limits for
Existing Designated Facilities Included in an Emissions Averaging
Plan at a Municipal Waste Combustor Plant b
Municipal waste combustor
technology
Before April 28, 2009,
nitrogen oxides emission limit
(parts per million by volume) b
On and after April 28,
2009,
nitrogen oxides emission limit
(parts per million by volume) a
Mass burn
waterwall
185
185
Mass burn rotary
waterwall
220
190
Refuse-derived
fuel combustor
230
230
Fluidized bed
combustor
165
165
a Mass burn refractory municipal
waste combustors and other MWC technologies not listed above may
not be included in an emissions averaging plan.
b Corrected to 7 percent oxygen,
dry basis.
[71 FR 27334, May 10, 2006]
Table 3 to Subpart Cb of Part 60 - Municipal Waste Combustor Operating Guidelines
40:7.0.1.1.1.6.1.11.4 :
Table 3 to Subpart Cb of Part 60 - Municipal Waste Combustor
Operating Guidelines
Municipal waste combustor
technology
Carbon monoxide emissions
levels (parts per million by volume) a
a Measured at the combustor
outlet in conjunction with a measurement of oxygen concentration,
corrected to 7 percent oxygen, dry basis. Calculated as an
arithmetic average.
b Averaging times are 4-hour or
24-hour block averages.
c 24-hour block average,
geometric mean.
[71 FR 27334, May 10, 2006]
Table 1A to Subpart Ce of Part 60 - Emissions Limits for Small, Medium, and Large HMIWI at Designated Facilities as Defined in § 60.32e(a)(1)
40:7.0.1.1.1.9.1.11.5 :
Table 1A to Subpart Ce of Part 60 - Emissions Limits for Small,
Medium, and Large HMIWI at Designated Facilities as Defined in §
60.32e(a)(1)
Pollutant
Units (7 percent
oxygen, dry basis)
Emissions
limits
Averaging time
1
Method for
demonstrating compliance 2
HMIWI size
Small
Medium
Large
Particulate
matter
Milligrams per dry standard
cubic meter (mg/dscm) (grains per dry standard cubic foot
(gr/dscf))
115 (0.05)
69 (0.03)
34 (0.015)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 5 of
appendix A-3 of part 60, or EPA Reference Method 26A or 29 of
appendix A-8 of part 60.
Carbon
monoxide
Parts per million by volume
(ppmv)
40
40
40
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 10 or 10B
of appendix A-4 of part 60.
Dioxins/furans
Nanograms per dry standard
cubic meter total dioxins/furans (ng/dscm) (grains per billion dry
standard cubic feet (gr/10 9 dscf)) or ng/dscm TEQ
(gr/10 9 dscf)
125 (55) or 2.3 (1.0)
125 (55) or 2.3 (1.0)
125 (55) or 2.3 (1.0)
3-run average (4-hour minimum
sample time per run)
EPA Reference Method 23 of
appendix A-7 of part 60.
Hydrogen
chloride
ppmv or percent reduction
100 or 93%
100 or 93%
100 or 93%
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 26 or 26A
of appendix A-8 of part 60.
Sulfur
dioxide
ppmv
55
55
55
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 6 or 6C
of appendix A-4 of part 60.
Nitrogen
oxides
ppmv
250
250
250
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 7 or 7E
of appendix A-4 of part 60.
Lead
mg/dscm (grains per thousand
dry standard cubic feet (gr/10 3 dscf)) or percent
reduction
1.2 (0.52) or 70%
1.2 (0.52) or 70%
1.2 (0.52) or 70%
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
Cadmium
mg/dscm (gr/10 3
dscf) or percent reduction
0.16 (0.07) or 65%
0.16 (0.07) or 65%
0.16 (0.07) or 65%
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
Mercury
mg/dscm (gr/10 3
dscf) or percent reduction
0.55 (0.24) or 85%
0.55 (0.24) or 85%
0.55 (0.24) or 85%
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
1 Except as allowed under §
60.56c(c) for HMIWI equipped with CEMS.
2 Does not include CEMS and
approved alternative non-EPA test methods allowed under §
60.56c(b).
Table 1B to Subpart Ce of Part 60 - Emissions Limits for Small, Medium, and Large HMIWI at Designated Facilities as Defined in § 60.32e(a)(1) and (a)(2)
40:7.0.1.1.1.9.1.11.6 :
Table 1B to Subpart Ce of Part 60 - Emissions Limits for Small,
Medium, and Large HMIWI at Designated Facilities as Defined in §
60.32e(a)(1) and (a)(2)
Pollutant
Units
(7 percent oxygen, dry basis)
Emissions
limits
Averaging time
1
Method for
demonstrating compliance 2
HMIWI size
Small
Medium
Large
Particulate
matter
Milligrams per dry standard
cubic meter (mg/dscm) (grains per dry standard cubic foot
(gr/dscf))
66 (0.029)
46 (0.020)
25 (0.011)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 5 of
appendix A-3 of part 60, or EPA Reference Method 26A or 29 of
appendix A-8 of part 60.
Carbon
monoxide
Parts per million by volume
(ppmv)
20
5.5
11
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 10 or 10B
of appendix A-4 of part 60.
Dioxins/furans
Nanograms per dry standard
cubic meter total dioxins/furans (ng/dscm) (grains per billion dry
standard cubic feet (gr/10 9 dscf)) or ng/dscm TEQ
(gr/10 9 dscf)
16 (7.0) or 0.013
(0.0057)
0.85 (0.37) or 0.020
(0.0087)
9.3 (4.1) or 0.054
(0.024)
3-run average (4-hour minimum
sample time per run)
EPA Reference Method 23 of
appendix A-7 of part 60.
Hydrogen
chloride
ppmv
44
7.7
6.6
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 26 or 26A
of appendix A-8 of part 60.
Sulfur
dioxide
ppmv
4.2
4.2
9.0
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 6 or 6C
of appendix A-4 of part 60.
Nitrogen
oxides
ppmv
190
190
140
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 7 or 7E
of appendix A-4 of part 60.
Lead
mg/dscm (grains per thousand
dry standard cubic feet (gr/10 3 dscf))
0.31 (0.14)
0.018 (0.0079)
0.036 (0.016)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
Cadmium
mg/dscm (gr/10 3
dscf)
0.017 (0.0074)
0.013 (0.0057)
0.0092 (0.0040)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
Mercury
mg/dscm (gr/10 3
dscf)
0.014 (0.0061)
0.025 (0.011)
0.018 (0.0079)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
1 Except as allowed under §
60.56c(c) for HMIWI equipped with CEMS.
2 Does not include CEMS and
approved alternative non-EPA test methods allowed under §
60.56c(b).
[74 FR 51406, Oct. 6, 2009]
Table 2A to Subpart Ce of Part 60 - Emissions Limits for Small HMIWI Which Meet the Criteria Under § 60.33e(b)(1)
40:7.0.1.1.1.9.1.11.7 :
Table 2A to Subpart Ce of Part 60 - Emissions Limits for Small
HMIWI Which Meet the Criteria Under § 60.33e(b)(1)
Pollutant
Units
(7 percent oxygen, dry basis)
HMIWI emissions limits
Averaging time
1
Method for demonstrating
compliance 2
Particulate
matter
mg/dscm (gr/dscf)
197 (0.086)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 5 of
appendix A-3 of part 60, or EPA Reference Method 26A or 29 of
appendix A-8 of part 60.
Carbon
monoxide
ppmv
40
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 10 or 10B
of appendix A-4 of part 60.
Dioxins/furans
ng/dscm total dioxins/furans
(gr/10 9 dscf) or ng/dscm TEQ (gr/10 9
dscf)
800 (350) or 15 (6.6)
3-run average (4-hour minimum
sample time per run)
EPA Reference Method 23 of
appendix A-7 of part 60.
Hydrogen
chloride
ppmv
3,100
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 26 or 26A
of appendix A-8 of part 60.
Sulfur
dioxide
ppmv
55
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 6 or 6C
of appendix A-4 of part 60.
Nitrogen
oxides
ppmv
250
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 7 or 7E
of appendix A-4 of part 60.
Lead
mg/dscm (gr/10 3
dscf)
10 (4.4)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
Cadmium
mg/dscm (gr/10 3
dscf)
4 (1.7)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
Mercury
mg/dscm (gr/10 3
dscf)
7.5 (3.3)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
1 Except as allowed under §
60.56c(c) for HMIWI equipped with CEMS.
2 Does not include CEMS and
approved alternative non-EPA test methods allowed under §
60.56c(b).
[74 FR 51407, Oct. 6, 2009]
Table 2B to Subpart Ce of Part 60 - Emissions Limits for Small HMIWI Which Meet the Criteria Under § 60.33e(b)(2)
40:7.0.1.1.1.9.1.11.8 :
Table 2B to Subpart Ce of Part 60 - Emissions Limits for Small
HMIWI Which Meet the Criteria Under § 60.33e(b)(2)
Pollutant
Units
(7 percent oxygen, dry basis)
HMIWI Emissions limits
Averaging time
1
Method for demonstrating
compliance 2
Particulate
matter
mg/dscm (gr/dscf)
87 (0.038)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 5 of
appendix A-3 of part 60, or EPA Reference Method 26A or 29 of
appendix A-8 of part 60.
Carbon
monoxide
ppmv
20
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 10 or 10B
of appendix A-4 of part 60.
Dioxins/furans
ng/dscm total dioxins/furans
(gr/10 9 dscf) or ng/dscm TEQ (gr/10 9
dscf)
240 (100) or 5.1 (2.2)
3-run average (4-hour minimum
sample time per run)
EPA Reference Method 23 of
appendix A-7 of part 60.
Hydrogen
chloride
ppmv
810
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 26 or 26A
of appendix A-8 of part 60.
Sulfur
dioxide
ppmv
55
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 6 or 6C
of appendix A-4 of part 60.
Nitrogen
oxides
ppmv
130
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 7 or 7E
of appendix A-4 of part 60.
Lead
mg/dscm (gr/10 3
dscf)
0.50 (0.22)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
Cadmium
mg/dscm (gr/10 3
dscf)
0.11 (0.048)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
Mercury
mg/dscm (gr/10 3
dscf)
0.0051 (0.0022)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
1 Except as allowed under §
60.56c(c) for HMIWI equipped with CEMS.
2 Does not include CEMS and
approved alternative non-EPA test methods allowed under §
60.56c(b).
[74 FR 51407, Oct. 6, 2009]
Table 1A to Subpart Ec of Part 60 - Emissions Limits for Small, Medium, and Large HMIWI at Affected Facilities as Defined in § 60.50c(a)(1) and (2)
40:7.0.1.1.1.18.1.10.9 :
Table 1A to Subpart Ec of Part 60 - Emissions Limits for Small,
Medium, and Large HMIWI at Affected Facilities as Defined in §
60.50c(a)(1) and (2)
Pollutant
Units (7 percent
oxygen, dry basis)
Emissions
limits
Averaging time
1
Method
for
demonstrating
compliance 2
HMIWI size
Small
Medium
Large
Particulate
matter
Milligrams per dry standard
cubic meter (grains per dry standard cubic foot)
69 (0.03)
34 (0.015)
34 (0.015)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 5 of
appendix A-3 of part 60, or EPA Reference Method M 26A or 29 of
appendix A-8 of part 60.
Carbon
monoxide
Parts per million by
volume
40
40
40
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 10 or 10B
of appendix A-4 of part 60.
Dioxins/furans
Nanograms per dry standard
cubic meter total dioxins/furans (grains per billion dry standard
cubic feet) or nanograms per dry standard cubic meter TEQ (grains
per billion dry standard cubic feet)
125 (55) or 2.3 (1.0)
25 (11) or 0.6 (0.26)
25 (11) or 0.6 (0.26)
3-run average (4-hour minimum
sample time per run)
EPA Reference Method 23 of
appendix A-7 of part 60.
Hydrogen
chloride
Parts per million by volume or
percent reduction
15 or 99%
15 or 99%
15 or 99%
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 26 or 26A
of appendix A-8 of part 60.
Sulfur
dioxide
Parts per million by
volume
55
55
55
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 6 or 6C
of appendix A-4 of part 60.
Nitrogen
oxides
Parts per million by
volume
250
250
250
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 7 or 7E
of appendix A-4 of part 60.
Lead
Milligrams per dry standard
cubic meter (grains per thousand dry standard cubic feet) or
percent reduction
1.2 (0.52) or 70%
0.07 (0.03) or 98%
0.07 (0.03) or 98%
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
Cadmium
Milligrams per dry standard
cubic meter (grains per thousand dry standard cubic feet) or
percent reduction
0.16 (0.07) or 65%
0.04 (0.02) or 90%
0.04 (0.02) or 90%
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
Mercury
Milligrams per dry standard
cubic meter (grains per thousand dry standard cubic feet) or
percent reduction
0.55 (0.24) or 85%
0.55 (0.24) or 85%
0.55 (0.24) or 85%
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
1 Except as allowed under §
60.56c(c) for HMIWI equipped with CEMS.
2 Does not include CEMS and
approved alternative non-EPA test methods allowed under §
60.56c(b).
[74 FR 51414, Oct. 6, 2009, as amended at 76 FR 18414, Apr. 4,
2011]
Table 1B to Subpart Ec of Part 60 - Emissions Limits for Small, Medium, and Large HMIWI at Affected Facilities as Defined in § 60.50c(a)(3) and (4)
40:7.0.1.1.1.18.1.10.10 :
Table 1B to Subpart Ec of Part 60 - Emissions Limits for Small,
Medium, and Large HMIWI at Affected Facilities as Defined in §
60.50c(a)(3) and (4)
Pollutant
Units
(7 percent oxygen,
dry basis)
Emissions
limits
Averaging time
1
Method for
demonstrating
compliance 2
HMIWI size
Small
Medium
Large
Particulate
matter
Milligrams per dry standard
cubic meter (grains per dry standard cubic foot)
66 (0.029)
22 (0.0095)
18 (0.0080)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 5 of
appendix A-3 of part 60, or EPA Reference Method M 26A or 29 of
appendix A-8 of part 60.
Carbon
monoxide
Parts per million by
volume
20
1.8
11
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 10 or 10B
of appendix A-4 of part 60.
Dioxins/furans
Nanograms per dry standard
cubic meter total dioxins/furans (grains per billion dry standard
cubic feet) or nanograms per dry standard cubic meter TEQ (grains
per billion dry standard cubic feet)
16 (7.0) or 0.013
(0.0057)
0.47 (0.21) or 0.014
(0.0061)
9.3 (4.1) or 0.035
(0.015)
3-run average (4-hour minimum
sample time per run)
EPA Reference Method 23 of
appendix A-7 of part 60.
Hydrogen
chloride
Parts per million by
volume
15
7.7
5.1
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 26 or 26A
of appendix A-8 of part 60.
Sulfur
dioxide
Parts per million by
volume
1.4
1.4
8.1
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 6 or 6C
of appendix A-4 of part 60.
Nitrogen
oxides
Parts per million by
volume
67
67
140
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 7 or 7E
of appendix A-4 of part 60.
Lead
Milligrams per dry standard
cubic meter (grains per thousand dry standard cubic feet)
0.31 (0.14)
0.018 (0.0079)
0.00069 (0.00030)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
Cadmium
Milligrams per dry standard
cubic meter (grains per thousand dry standard cubic feet)
0.017 (0.0074)
0.0098 (0.0043)
0.00013 (0.000057)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
Mercury
Milligrams per dry standard
cubic meter (grains per thousand dry standard cubic feet)
0.014 (0.0061)
0.0035 (0.0015)
0.0013 (0.00057)
3-run average (1-hour minimum
sample time per run)
EPA Reference Method 29 of
appendix A-8 of part 60.
1 Except as allowed under §
60.56c(c) for HMIWI equipped with CEMS.
2 Does not include CEMS and
approved alternative non-EPA test methods allowed under §
60.56c(b).
[74 FR 51414, Oct. 6, 2009, as amended at 76 FR 18414, Apr. 4,
2011]
Table 2 to Subpart Ec of Part 60 - Toxic Equivalency Factors
40:7.0.1.1.1.18.1.10.11 :
Table 2 to Subpart Ec of Part 60 - Toxic Equivalency Factors
Dioxin/furan congener
Toxic equivalency factor
2,3,7,8-tetrachlorinated dibenzo-p-dioxin
1
1,2,3,7,8-pentachlorinated dibenzo-p-dioxin
0.5
1,2,3,4,7,8-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,7,8,9-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,6,7,8-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,4,6,7,8-heptachlorinated dibenzo-p-dioxin
0.01
octachlorinated
dibenzo-p-dioxin
0.001
2,3,7,8-tetrachlorinated dibenzofuran
0.1
2,3,4,7,8-pentachlorinated dibenzofuran
0.5
1,2,3,7,8-pentachlorinated dibenzofuran
0.05
1,2,3,4,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,6,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,7,8,9-hexachlorinated dibenzofuran
0.1
2,3,4,6,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,4,6,7,8-heptachlorinated dibenzofuran
0.01
1,2,3,4,7,8,9-heptachlorinated dibenzofuran
0.01
Octachlorinated
dibenzofuran
0.001
Table 3 to Subpart Ec of Part 60 - Operating Parameters To Be Monitored and Minimum Measurement and Recording Frequencies
40:7.0.1.1.1.18.1.10.12 :
Table 3 to Subpart Ec of Part 60 - Operating Parameters To Be
Monitored and Minimum Measurement and Recording Frequencies
Operating
parameters to be monitored
Minimum
frequency
Control
system
Data measurement
Data recording
Dry scrubber followed by
fabric filter
Wet scrubber
Dry scrubber followed by
fabric filter and wet scrubber
Maximum operating
parameters:
Maximum charge
rate
Continuous
1 × hour
✔
✔
✔
Maximum fabric
filter inlet temperature
Continuous
1 × minute
✔
✔
Maximum flue
gas temperature
Continuous
1 × minute
✔
✔
Minimum operating
parameters:
Minimum
secondary chamber temperature
Continuous
1 × minute
✔
✔
✔
Minimum
dioxin/furan sorbent flow rate
Hourly
1 × hour
✔
✔
Minimum HCI
sorbent flow rate
Hourly
1 × hour
✔
✔
Minimum mercury
(Hg) sorbent flow rate
Hourly
1 × hour
✔
✔
Minimum
pressure drop across the wet scrubber or minimum horsepower or
amperage to wet scrubber
Continuous
1 × minute
✔
✔
Minimum
scrubber liquor flow rate
Continuous
1 × minute
✔
✔
Minimum
scrubber liquor pH
Continuous
1 × minute
✔
✔
Table 1 to Subpart Ja of Part 60 - Molar Exhaust Volumes and Molar Heat Content of Fuel Gas Constituents
40:7.0.1.1.1.25.1.11.13 :
Table 1 to Subpart Ja of Part 60 - Molar Exhaust Volumes and Molar
Heat Content of Fuel Gas Constituents
Constituent
MEV a
dscf/mol
MHC b
Btu/mol
Methane (CH4)
7.29
842
Ethane (C2H6)
12.96
1,475
Hydrogen (H2)
1.61
269
Ethene (C2H4)
11.34
1,335
Propane
(C3H8)
18.62
2,100
Propene
(C3H6)
17.02
1,947
Butane
(C4H10)
24.30
2,717
Butene (C4H8)
22.69
2,558
Inerts
0.85
0
a MEV = molar exhaust volume, dry
standard cubic feet per gram-mole (dscf/g-mol) at standard
conditions of 68 °F and 1 atmosphere.
b MHC = molar heat content
(higher heating value basis), Btu per gram-mole (Btu/g-mol).
[77 FR 56480, Sep. 12, 2012]
Table 1 to Subpart OOO of Part 60 - Exceptions to Applicability of Subpart A to Subpart OOO
40:8.0.1.1.1.17.163.8.1 :
Table 1 to Subpart OOO of Part 60 - Exceptions to Applicability of
Subpart A to Subpart OOO
Subpart A reference
Applies to
subpart OOO
Explanation
60.4, Address
Yes
Except in § 60.4(a) and (b)
submittals need not be submitted to both the EPA Region and
delegated State authority (§ 60.676(k)).
60.7, Notification
and recordkeeping
Yes
Except in (a)(1) notification
of the date construction or reconstruction commenced (§
60.676(h)).
Also, except in (a)(6)
performance tests involving only Method 9 (40 CFR part 60, appendix
A-4) require a 7-day advance notification instead of 30 days (§
60.675(g)).
60.8, Performance
tests
Yes
Except in (d) performance
tests involving only Method 9 (40 CFR part 60, appendix A-4)
require a 7-day advance notification instead of 30 days (§
60.675(g)).
60.11, Compliance
with standards and maintenance requirements
Yes
Except in (b) under certain
conditions (§§ 60.675(c)), Method 9 (40 CFR part 60, appendix A-4)
observation is reduced from 3 hours to 30 minutes for fugitive
emissions.
60.18, General
control device
No
Flares will not be used to
comply with the emission limits.
Table 2 to Subpart OOO of Part 60 - Stack Emission Limits for Affected Facilities With Capture Systems
40:8.0.1.1.1.17.163.8.2 :
Table 2 to Subpart OOO of Part 60 - Stack Emission Limits for
Affected Facilities With Capture Systems
For * * *
The owner or operator must
meet a PM limit of * * *
And the owner or operator
must meet an opacity limit of * * *
The owner or operator must
demonstrate compliance with these limits by conducting * * *
Affected
facilities (as defined in §§ 60.670 and 60.671) that commenced
construction, modification, or reconstruction after August 31, 1983
but before April 22, 2008
0.05 g/dscm (0.022 gr/dscf)
a
7 percent for dry control
devices b
An initial performance test
according to § 60.8 of this part and § 60.675 of this subpart;
and
Monitoring of wet scrubber parameters according to § 60.674(a) and
§ 60.676(c), (d), and (e).
Affected
facilities (as defined in §§ 60.670 and 60.671) that commence
construction, modification, or reconstruction on or after April 22,
2008
0.032 g/dscm (0.014 gr/dscf)
a
Not applicable (except for
individual enclosed storage bins)
7 percent for dry control devices on individual enclosed storage
bins
An initial performance test
according to § 60.8 of this part and § 60.675 of this subpart;
and
Monitoring of wet scrubber parameters according to § 60.674(a) and
§ 60.676(c), (d), and (e); and
Monitoring of baghouses
according to § 60.674(c), (d), or (e) and § 60.676(b).
a Exceptions to the PM limit
apply for individual enclosed storage bins and other equipment. See
§ 60.672(d) through (f).
b The stack opacity limit and
associated opacity testing requirements do not apply for affected
facilities using wet scrubbers.
Table 3 to Subpart OOO of Part 60 - Fugitive Emission Limits
40:8.0.1.1.1.17.163.8.3 :
Table 3 to Subpart OOO of Part 60 - Fugitive Emission Limits
For * * *
The owner or operator must
meet the following fugitive emissions limit for grinding mills,
screening operations, bucket elevators, transfer points on belt
conveyors, bagging operations, storage bins, enclosed truck or
railcar loading stations or from any other affected facility (as
defined in §§ 60.670 and 60.671) * * *
The owner or operator must
meet the following fugitive emissions limit for crushers at which a
capture system is not used * * *
The owner or operator must
demonstrate compliance with these limits by conducting * * *
Affected
facilities (as defined in §§ 60.670 and 60.671) that commenced
construction, modification, or reconstruction after August 31, 1983
but before April 22, 2008
10 percent opacity
15 percent opacity
An initial performance test
according to § 60.11 of this part and § 60.675 of this
subpart.
Affected
facilities (as defined in §§ 60.670 and 60.671) that commence
construction, modification, or reconstruction on or after April 22,
2008
7 percent opacity
12 percent opacity
An initial performance test
according to § 60.11 of this part and § 60.675 of this subpart;
and
Periodic inspections of water sprays according to § 60.674(b) and §
60.676(b); and
A repeat performance test
according to § 60.11 of this part and § 60.675 of this subpart
within 5 years from the previous performance test for fugitive
emissions from affected facilities without water sprays. Affected
facilities controlled by water carryover from upstream water sprays
that are inspected according to the requirements in §§ 60.674(b)
and 60.676(b) are exempt from this 5-year repeat testing
requirement.
Table 1 to Subpart AAAA of Part 60 - Emission Limits for New Small Municipal Waste Combustion Units
40:8.0.1.1.1.28.179.95.4 :
Table 1 to Subpart AAAA of Part 60 - Emission Limits for New Small
Municipal Waste Combustion Units
For the following
pollutants
You must meet the
following emission limits a
Using the following
averaging times
And determine compliance by
the following methods
1. Organics
Dioxins/Furans
(total mass basis)
13 nanograms per dry standard
cubic meter
3-run average (minimum run
duration is 4 hours)
Stack test.
2. Metals:
Cadmium
0.020 milligrams per dry
standard cubic meter
3-run average (run duration
specified in test method)
Stack test.
Lead
0.20 milligrams per dry
standard cubic meter
3-run average (run duration
specified in test method)
Stack test.
Mercury
0.080 milligrams per dry
standard cubic meter or 85 percent reduction of potential mercury
emissions
3-run average (run duration
specified in test method)
Stack test.
Opacity
10 percent
Thirty 6-minute averages
Stack test.
Particulate
Matter
24 milligrams per dry standard
cubic meter
3-run average (run duration
specified in test method)
Stack test.
3. Acid
Gases:
Hydrogen
Chloride
25 parts per million by dry
volume or 95 percent reduction of potential hydrogen chloride
emissions
3-run average (minimum run
duration is 1 hour)
Stack test
Nitrogen Oxides
(Class I units) b
150 (180 for 1st year of
operation) parts per million by dry volume
24-hour daily block arithmetic
average concentration
Continuous emission monitoring
system.
Nitrogen Oxides
(Class II units) c
500 parts per million by dry
volume
See footnote d
See footnote d
Sulfur
Dioxide
30 parts per million by dry
volume or 80 percent reduction of potential sulfur dioxide
emissions
24-hour daily block geometric
average concentration or percent reduction
Continuous monitoring emission
system.
4. Other:
Fugitive
Ash
Visible emissions for no more
than 5 percent of hourly observation period
Three 1-hour observation
periods
Visible emission test.
a All emission limits (except for
opacity) are measured at 7 percent oxygen.
b Class I units mean small
municipal waste combustion units subject to this subpart that are
located at municipal waste combustion plants with an aggregate
plant combustion capacity more than 250 tons per day of municipal
solid waste. See § 60.1465 for definitions.
c Class II units mean small
municipal waste combustion units subject to this subpart that are
located at municipal waste combustion plants with an aggregate
plant combustion capacity no more than 250 tons per day of
municipal solid waste. See § 60.1465 for definitions.
d No monitoring, testing,
recordkeeping, or reporting is required to demonstrate compliance
with the nitrogen oxides limit for Class II units.
Table 2 to Subpart AAAA of Part 60 - Carbon Monoxide Emission Limits for New Small Municipal Waste Combustion Units
40:8.0.1.1.1.28.179.95.5 :
Table 2 to Subpart AAAA of Part 60 - Carbon Monoxide Emission
Limits for New Small Municipal Waste Combustion Units
For the following municipal
waste combustion units
You must meet the
following
carbon monoxide limits a
a All limits (except for opacity)
are measured at 7 percent oxygen. Compliance is determined by
continuous emission monitoring systems.
b Block averages, arithmetic
mean. See § 60.1465 for definitions.
c 24-hour block average,
geometric mean. See § 60.1465 for definitions.
Table 3 to Subpart AAAA of Part 60 - Requirements for Validating Continuous Emission Monitoring Systems (CEMS)
40:8.0.1.1.1.28.179.95.6 :
Table 3 to Subpart AAAA of Part 60 - Requirements for Validating
Continuous Emission Monitoring Systems (CEMS)
For the following continuous
emission monitoring systems
Use the following methods in
appendix A of this part to validate pollutant concentration
levels
Use the following methods in
appendix A of this part to measure oxygen (or carbon dioxide)
1. Nitrogen Oxides
(Class I units only) a
Method 7, 7A, 7B, 7C, 7D, or
7E
Method 3 or 3A.
2. Sulfur
Dioxide
Method 6 or 6C
Method 3 or 3A.
3. Carbon
Monoxide
Method 10, 10A, or 10B
Method 3 or 3A.
a Class I units mean small
municipal waste combustion units subject to this subpart that are
located at municipal waste combustion plants with an aggregate
plant combustion capacity more than 250 tons per day of municipal
solid waste. See § 60.1465 for definitions.
Table 4 to Subpart AAAA of Part 60 - Requirements for Continuous Emission Monitoring Systems (CEMS)
40:8.0.1.1.1.28.179.95.7 :
Table 4 to Subpart AAAA of Part 60 - Requirements for Continuous
Emission Monitoring Systems (CEMS)
For the following
pollutants
Use the following span values
for your CEMS
Use the following performance
specifications in appendix B of this part for your CEMS
If needed to meet minimum
data requirements, use the
following alternate methods
in appendix A of this part
to collect data
1. Opacity
100 percent opacity
P.S. 1
Method 9.
2. Nitrogen Oxides
(Class I units only) a
Control device outlet: 125
percent of the maximum expected hourly potential nitrogen oxides
emissions of the municipal waste combustion unit
P.S. 2
Method 7E.
3. Sulfur
Dioxide
Inlet to control device: 125
percent of the maximum expected sulfur dioxide emissions of the
municipal waste combustion unit. Control device outlet: 50 percent
of the maximum expected hourly potential sulfur dioxide emissions
of the municipal waste combustion unit
P.S. 2
Method 6C.
4. Carbon
Monoxide
125 percent of the maximum
expected hourly potential carbon with monoxide emissions of the
municipal waste combustion unit
P.S. 4A
Method 10 alternative
interference trap.
5. Oxygen or
Carbon Dioxide
25 percent oxygen or 25
percent carbon dioxide
P.S. 3
Method 3A or 3B.
a Class I units mean small
municipal waste combustion units subject to this subpart that are
located at municipal waste combustion plants with an aggregate
plant combustion capacity more than 250 tons per day of municipal
solid waste. See § 60.1465 for definitions.
Table 5 to Subpart AAAA of Part 60 - Requirements for Stack Tests
40:8.0.1.1.1.28.179.95.8 :
Table 5 to Subpart AAAA of Part 60 - Requirements for Stack Tests
To measure the following
pollutants
Use the following methods in
appendix A of this part to determine the sampling location
Use the methods in appendix A
of this part to measure pollutant concentration
Also note the following
additional information
1. Organics:
Dioxins/Furans
Method 1
Method 23 a
The minimum sampling time must
be 4 hours per test run while the municipal waste combustion unit
is operating at full load.
2. Metals:
Cadmium
Method 1
Method 29 a
Compliance testing must be
performed while the municipal waste combustion unit is operating at
full load.
Lead
Method 1
Method 29 a
Compliance testing must be
performed while the municipal waste combustion unit is operating at
full load.
Mercury
Method 1
Method 29 a
Compliance testing must be
performed while the municipal waste combustion unit is operating at
full load.
Opacity
Method 9
Method 9
Use Method 9 to determine
compliance with opacity limit. 3-hour observation period (thirty
6-minute averages).
Particulate
Matter
Method 1
Method 5 a
The minimum sample Matter
volume must be 1.0 cubic meters. The probe and filter holder
heating systems in the sample train must be set to provide a gas
temperature no greater than 160 ±14 °C. The minimum sampling time
is 1 hour.
3. Acid Gases:
b
Hydrogen
Chloride
Method 1
Method 26 or 26A
a
Test runs must be at least 1
hour long while the municipal waste combustion unit is operating at
full load.
4. Other:
b
Fugitive
Ash
Not applicable
Method 22 (visible
emissions)
The three 1-hour observation
period must include periods when the facility transfers fugitive
ash from the municipal waste combustion unit to the area where the
fugitive ash is stored or loaded into containers or trucks.
a Must simultaneously measure
oxygen (or carbon dioxide) using Method 3A or 3B in appendix A of
this part.
b Use CEMS to test sulfur
dioxide, nitrogen oxide, and carbon monoxide. Stack tests are not
required except for quality assurance requirements in appendix F of
this part.
Table 1 to Subpart BBBB of Part 60 - Model Rule - Compliance Schedules and Increments of Progress
40:8.0.1.1.1.29.195.90.9 :
Table 1 to Subpart BBBB of Part 60 - Model Rule - Compliance
Schedules and Increments of Progress
Affected units
Increment 1 (Submit final
control plan)
Increment 2 (Award
contracts)
Increment 3 (Begin onsite
construction)
Increment 4 (Complete onsite
construction)
Increment 5 (Final
compliance)
1. All Class I
units a b
(Dates to be specified in
State plan)
(Dates to be specified in
State plan)
(Dates to be specified in
State plan)
(Dates to be specified in
State plan)
(Dates to be specified in
State plan). c d
2. All Class II
units a e
(Dates to be specified in
State plan)
Not applicable
Not applicable
Not applicable
(Dates to be specified in
State plan). c
a Plant specific schedules can be
used at the discretion of the State.
b Class I units mean small
municipal waste combustion units subject to this subpart that are
located at municipal waste combustion plants with an aggregate
plant combustion capacity greater than 250 tons per day of
municipal solid waste. See § 60.1940 for definitions.
c The date can be no later than 3
years after the effective date of State plan approval or December
6, 2005.
d For Class I units that began
construction, reconstruction, or modification after June 26, 1987,
comply with the dioxins/furans and mercury limits by the later of
two dates:
1. One year after the effective date of
State plan approval.
2. One year after the issuance of a revised
construction or operation permit, if a permit modification is
required.
3. Final compliance with the dioxins/furans
limits must be achieved no later than December 6, 2005, even if the
date one year after the issuance of a revised construction or
operation permit is after December 6, 2005.
e Class II units mean all small
municipal combustion units subject to this subpart that are located
at municipal waste combustion plants with aggregate plant
combustion capacity less than or equal to 250 tons per day of
municipal solid waste. See § 60.1940 for definitions.
Table 2 to Subpart BBBB of Part 60 - Model Rule - Class I Emission Limits for Existing Small Municipal Waste Combustion Units a
40:8.0.1.1.1.29.195.90.10 :
Table 2 to Subpart BBBB of Part 60 - Model Rule - Class I Emission
Limits for Existing Small Municipal Waste Combustion Units a
For the following
pollutants
You must meet the following
emission limits b
Using the following averaging
times
And determine compliance by
the following methods
1. Organics:
Dioxins/Furans
(total mass basis)
30 nanograms per dry standard
cubic meter for municipal waste combustion units that do not employ
an electrostatic precipitator-based emission control system
-or-
3-run average (minimum run
duration is 4 hours)
Stack test.
60 nanograms per dry standard
cubic meter for municipal waste combustion units that employ an
electrostatic precipitator-based emission control system
2. Metals:
Cadmium
0.040 milligrams per dry
standard cubic meter
3-run average (run duration
specified in test method)
Stack test.
Lead
0.490 milligrams per dry
standard cubic meter
3-run average (run duration
specified in test method)
Stack test.
Mercury
0.080 milligrams per dry
standard cubic meter
3-run average (run duration
specified in test method)
Stack test.
85 percent reduction of
potential mercury emissions
Opacity
10 percent
Thirty 6-minute averages
Stack test.
Particulate
Matter
27 milligrams per dry standard
cubic meter
3-run average (run duration
specified in test method)
Stack test.
3. Acid
Gases:
Hydrogen
Chloride
31 parts per million by dry
volume 95 percent reduction of potential hydrogen chloride
emissions
3-run average (minimum run
duration is 1 hour)
Stack test.
Sulfur
Dioxide
31 parts per million by dry
volume 75 percent reduction of potential sulfur dioxide
emissions
24-hour daily block geometric
average concentration percent reduction
Continuous emission monitoring
system.
4. Other:
Fugitive
Ash
Visible emissions for no more
than 5 percent of hourly observation period
Three 1-hour observation
periods
Visible emission test.
a Class I units mean small
municipal waste combustion units subject to this subpart that are
located at municipal waste combustion plants with an aggregate
plant combustion capacity greater than 250 tons per day of
municipal solid waste. See § 60.1940 for definitions.
b All emission limits (except for
opacity) are measured at 7 percent oxygen.
Table 3 to Subpart BBBB of Part 60 - Model Rule - Class I Nitrogen Oxides Emission Limits for Existing Small Municipal Waste Combustion Units a b c
40:8.0.1.1.1.29.195.90.11 :
Table 3 to Subpart BBBB of Part 60 - Model Rule - Class I Nitrogen
Oxides Emission Limits for Existing Small Municipal Waste
Combustion Units a b c
Municipal waste combustion
technology
Limits for class I municipal
waste combustion units
1. Mass burn
waterwall
200 parts per million by dry
volume.
2. Mass burn
rotary waterwall
170 parts per million by dry
volume.
3. Refuse-derived
fuel
250 parts per million by dry
volume.
4. Fluidized
bed
220 parts per million by dry
volume.
5. Mass burn
refractory
350 parts per million by dry
volume.
6. Modular excess
air
190 parts per million by dry
volume.
7. Modular starved
air
380 parts per million by dry
volume.
a Class I units mean small
municipal waste combustion units subject to this subpart that are
located at municipal waste combustion plants with an aggregate
plant combustion capacity greater than 250 tons per day of
municipal solid waste. See § 60.1940 for definitions.
b Nitrogen oxides limits are
measured at 7 percent oxygen.
c All limits are 24-hour daily
block arithmetic average concentration. Compliance is determined
for Class I units by continuous emission monitoring systems.
Table 4 to Subpart BBBB of Part 60 - Model Rule - Class II Emission Limits for Existing Small Municipal Waste Combustion Unit a
40:8.0.1.1.1.29.195.90.12 :
Table 4 to Subpart BBBB of Part 60 - Model Rule - Class II Emission
Limits for Existing Small Municipal Waste Combustion Unit a
For the following
pollutants
You must meet the following
emission following determine limits b
Using the following averaging
times
And determine compliance by
the following methods
1. Organics:
Dioxins/Furans
(total mass basis)
125 nanorgrams per dry
standard cubic meter
3-run average (minimum run
duration is 4 hours)
Stack test.
2. Metals:
Cadmium
0.10 milligrams per dry
standard cubic meter
3-run average (run duration
specified in test method)
Stack test.
Lead
1.6 milligrams per dry
standard cubic meter
3-run average (run duration
specified in test method)
Stack test.
Mercury
0.080 milligrams per dry
standard cubic meter
3-run average (run duration
specified in test method)
Stack test.
85 percent reduction of
potential mercury emissions
Opacity
10 percent
Thirty 6-minute average
Stack test.
Particulate
Matter
70 milligrams per dry standard
cubic meter
3-run average (run duration
specified in test method)
Stack test.
3. Acid
Gases:
Hydrogen
Chloride
250 parts per million by
volume -or-
3-run average (minimum run
duration is 1 hour)
Stack test.
50 percent reduction of
potential hydrogen chloride emissions
Sulfur
Dioxide
77 parts per million by dry
volume -or-
50 percent reduction of potential sulfur dioxides emissions
24-hour daily block geometric
average concentration -or- percent reduction
Continuous emission monitoring
system.
4. Other:
Fugitive
Ash
Visible emissions for no more
than 5 percent of hourly observation period
Three 1-hour observation
periods
Visible emission test.
a Class II units mean all small
municipal combustion units subject to this subpart that are located
at municipal waste combustion plants with aggregate plant
combustion capacity less than or equal to 250 tons per day of
municipal solid waste. See § 60.1940 for definitions.
b All emission limits (except for
opacity) are measured at 7 percent oxygen.
c No monitoring, testing,
recordkeeping or reporting is required to demonstrate compliance
with the nitrogen oxides limit for Class II units.
Table 5 to Subpart BBBB of Part 60 - Model Rule - Carbon Monoxide Emission Limits for Existing Small Municipal Waste Combustion Units
40:8.0.1.1.1.29.195.90.13 :
Table 5 to Subpart BBBB of Part 60 - Model Rule - Carbon Monoxide
Emission Limits for Existing Small Municipal Waste Combustion Units
For the following municipal
waste combustion units
You must meet the following
carbon monoxide limits a
a All emission limits (except for
opacity) are measured at 7 percent oxygen. Compliance is determined
by continuous emission monitoring systems.
b Block averages, arithmetic
mean. See § 60.1940 for definitions.
c 24-hour block average,
geometric mean.
Table 6 to Subpart BBBB of Part 60 - Model Rule - Requirements for Validating Continuous Emission Monitoring Systems (CEMS)
40:8.0.1.1.1.29.195.90.14 :
Table 6 to Subpart BBBB of Part 60 - Model Rule - Requirements for
Validating Continuous Emission Monitoring Systems (CEMS)
For the following continuous
emission monitoring systems
Use the following methods in
appendix A of this part to validate poollutant concentratin
levels
Use the following methods in
appendix A of this part to measure oxygen (or carbon dioxide)
1. Nitrogen Oxides
(Class I units only) a
Method 7, 7A, 7B,7C, 7D, or
7E
Method 3 or 3A.
2. Sulfur
Dioxide
Method 6 or 6C
Method 3 or 3A.
3. Carbon
Monoxide
Method 10, 10A, or 10B
Method 3 or 3A.
a Class I units mean small
municipal waste combustion units subject to this subpart that are
located at municipal waste combustion plants with an aggregate
plant combustion capacity greater than 250 tons per day of
municipal solid waste. See § 60.1940 for definitions.
Table 7 to Subpart BBBB of Part 60 - Model Rule - Requirements for Continuous Emission Monitoring Systems (CEMS)
40:8.0.1.1.1.29.195.90.15 :
Table 7 to Subpart BBBB of Part 60 - Model Rule - Requirements for
Continuous Emission Monitoring Systems (CEMS)
For the following
pollutants
Use the following span values
for CEMS
Use the following performance
specifications in appendix B of this part for your CEMS
If needed to meet minimum
data requirements, use the following alternate methods in appendix
A of this part to collect data
1. Opacity
100 percent opacity
P.S. 1
Method 9.
2. Nitrogen Oxides
(Class I units only)
Control device outlet: 125
percent of the maximum expected hourly potential nitrogen oxides
emissions of the municipal waste combustion unit
P.S. 2
Method 7E.
3. Sulfur
Dioxide
Inlet to control device: 125
percent of the maximum expected hourly potential sulfur dioxide
emissions of the municipal waste combustion unit
P.S. 2
Method 6C.
Control device outlet: 50
percent of the maximum expected hourly potential sulfur dioxide
emissions of the municipal waste combustion unit
4. Carbon
Monoxide
125 percent of the maximum
expected hourly potential carbon monoxide emissions of the
municipal waste combustion unit
P.S. 4A
Method 10 with alternative
interference trap.
5. Oxygen or
Carbon Dioxide
25 percent oxygen or 25
percent carbon dioxide
P.S. 3
Method 3A or 3B.
Table 8 to Subpart BBBB of Part 60 - Model Rule - Requirements for Stack Tests
40:8.0.1.1.1.29.195.90.16 :
Table 8 to Subpart BBBB of Part 60 - Model Rule - Requirements for
Stack Tests
To measure the following
pollutants
Use the following methods in
appendix A of this part to determine the sampling location
Use the following methods in
appendix A of this part to measure pollutant concentration
Also note the following
additional information
1. Organics
Dioxins/Furans
Method 1
Method 23 a
The minimum sampling time must
be 4 hours per test run while the municipal waste combustion unit
is operating at full load.
2. Metals
Cadmium
Method 1
Method 29 a
Compliance testing must be
performed while the municipal waste combustion unit is operating at
full load.
Lead
Method 1
Method 29 a
Compliance testing must be
performed while the municipal waste combustion unit is operating at
full load.
Mercury
Method 1
Method 29 a
Compliance testing must be
performed while the municipal waste combustion unit is operating at
full load.
Opacity
Method 9
Method 9
Use Method 9 to determine
compliance with opacity limits. 3-hour observation period (thirty
6-minute averages).
Particulate
Matter
Method 1
Method 5 or 29
The minimum sample volume must
be 1.0 cubic meters. The probe and filter holder heating systems in
the sample train must be set to provide a gas temperature no
greater than 160 ±14 °C. The minimum sampling time is 1 hour.
3. Acid Gases
b
Hydrogen
Chloride
Method 1
Method 26 or 26A
a
Test runs must be at least 1
hour long while the municipal waste combustion unit is operating at
full load.
4. Other
b
Fugitive
Ash
Not applicable
Method 22 (visible
emissions)
The three 1-hour observation
period must include periods when the facility transfers fugitive
ash from the municipal waste combustion unit to the area where the
fugitive ash is stored or loaded into containers or trucks.
a Must simultaneously measure
oxygen (or carbon dioxide) using Method 3A or 3B in appendix A of
this part.
b Use CEMS to test sulfur
dioxide, nitrogen oxide, and carbon monoxide. Stack tests are not
required except for quality assurance requirements in appendix F of
this part.
Table 1 to Subpart CCCC of Part 60 - Emission Limitations for Incinerators for Which Construction is Commenced After November 30, 1999, But no Later Than June 4, 2010, or for Which Modification or Reconstruction is Commenced on or After June 1, 2001, But no Later Than August 7, 2013
40:8.0.1.1.1.30.209.56.17 :
Table 1 to Subpart CCCC of Part 60 - Emission Limitations for
Incinerators for Which Construction is Commenced After November 30,
1999, But no Later Than June 4, 2010, or for Which Modification or
Reconstruction is Commenced on or After June 1, 2001, But no Later
Than August 7, 2013
For the air pollutant
You must meet this
emission limitation 1
Using this averaging time
2
And determining
compliance
using this method 2
Cadmium
0.004 milligrams per dry
standard cubic meter
3-run average (1 hour minimum
sample time per run)
Performance test (Method 29 of
appendix A of this part).
Carbon
monoxide
157 parts per million by dry
volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 10 at
40 CFR part 60, appendix A-4).
Dioxin/Furan
(toxic equivalency basis)
0.41 nanograms per dry
standard cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meters per run)
Performance test (Method 23 of
appendix A-7 of this part).
Hydrogen
chloride
62 parts per million by dry
volume
3-run average (For Method 26,
collect a minimum volume of 120 liters per run. For Method 26A,
collect a minimum volume of 1 dry standard cubic meter per
run)
Performance test (Method 26 or
26A at 40 CFR part 60, appendix A-8).
Lead
0.04 milligrams per dry
standard cubic meter
3-run average (1 hour minimum
sample time per run)
Performance test (Method 29 of
appendix A of this part).
Mercury
0.47 milligrams per dry
standard cubic meter
3-run average (1 hour minimum
sample time per run)
Performance test (Method 29 of
appendix A of this part).
Nitrogen
oxides
388 parts per million by dry
volume
3-run average (for Method 7E,
1 hour minimum sample time per run)
Performance test (Method 7 or
7E at 40 CFR part 60, appendix A-4).
Opacity
10 percent
6-minute averages
Performance test (Method 9 of
appendix A of this part).
Particulate
matter
70 milligrams per dry standard
cubic meter
3-run average (1 hour minimum
sample time per run)
Performance test (Method 5 or
29 of appendix A of this part).
Sulfur
dioxide
20 parts per million by dry
volume
3-run average (For Method 6,
collect a minimum volume of 20 liters per run. For Method 6C,
collect sample for a minimum duration of 1 hour per run)
Performance test (Method 6 or
6C at 40 CFR part 60, appendix A-4).
1 All emission limitations
(except for opacity) are measured at 7 percent oxygen, dry basis at
standard conditions.
2 In lieu of performance testing,
you may use a CEMS or, for mercury, an integrated sorbent trap
monitoring system, to demonstrate initial and continuing compliance
with an emissions limit, as long as you comply with the CEMS or
integrated sorbent trap monitoring system requirements applicable
to the specific pollutant in §§ 60.2145 and 60.2165. As prescribed
in § 60.2145(u), if you use a CEMS or an integrated sorbent trap
monitoring system to demonstrate compliance with an emissions
limit, your averaging time is a 30-day rolling average of 1-hour
arithmetic average emission concentrations.
Table 2 to Subpart CCCC of Part 60 - Operating Limits for Wet Scrubbers
40:8.0.1.1.1.30.209.56.18 :
Table 2 to Subpart CCCC of Part 60 - Operating Limits for Wet
Scrubbers
For these
operating parameters
You must
establish these operating limits
And monitoring
using these minimum frequencies
Data measurement
Data recording
Averaging time
Charge rate
Maximum charge rate
Continuous
Every hour
Daily (batch units) 3-hour
rolling (continuous and intermittent units). 1
Pressure drop
across the wet scrubber or amperage to wet scrubber
Minimum pressure drop or
amperage
Continuous
Every 15 minutes
3-hour rolling.
1
Scrubber liquor
flow rate
Minimum flow rate
Continuous
Every 15 minutes
3-hour rolling.
1
Scrubber liquor
pH
Minimum pH
Continuous
Every 15 minutes
3-hour rolling.
1
1 Calculated each hour as the
average of the previous 3 operating hours.
Table 3 to Subpart CCCC of Part 60 - Toxic Equivalency Factors
40:8.0.1.1.1.30.209.56.19 :
Table 3 to Subpart CCCC of Part 60 - Toxic Equivalency Factors
Dioxin/furan congener
Toxic
equivalency
factor
2,3,7,8-tetrachlorinated dibenzo-p-dioxin
1
1,2,3,7,8-pentachlorinated dibenzo-p-dioxin
0.5
1,2,3,4,7,8-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,7,8,9-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,6,7,8-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,4,6,7,8-heptachlorinated dibenzo-p-dioxin
0.01
octachlorinated
dibenzo-p-dioxin
0.001
2,3,7,8-tetrachlorinated dibenzofuran
0.1
2,3,4,7,8-pentachlorinated dibenzofuran
0.5
1,2,3,7,8-pentachlorinated dibenzofuran
0.05
1,2,3,4,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,6,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,7,8,9-hexachlorinated dibenzofuran
0.1
2,3,4,6,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,4,6,7,8-heptachlorinated dibenzofuran
0.01
1,2,3,4,7,8,9-heptachlorinated dibenzofuran
0.01
octachlorinated
dibenzofuran
0.001
Table 4 to Subpart CCCC of Part 60 - Summary of Reporting Requirements 1
40:8.0.1.1.1.30.209.56.20 :
Table 4 to Subpart CCCC of Part 60 - Summary of Reporting
Requirements 1
Report
Due date
Contents
Reference
Preconstruction
report
Prior to commencing
construction
• Statement of intent to
construct
§ 60.2190.
• Anticipated date of
commencement of construction
• Documentation for siting requirements
• Waste management plan
• Anticipated date of initial startup
Startup
notification
Prior to initial startup
• Type of waste to be
burned
§ 60.2195.
• Maximum design waste burning
capacity
• Anticipated maximum charge rate
• If applicable, the petition for site-specific operating
limits
Initial test
report
No later than 60 days
following the initial performance test
• Complete test report for the
initial performance test
• The values for the site-specific operating limits
§ 60.2200.
• Installation of bag leak
detection system for fabric filter
Annual report
No later than 12 months
following the submission of the initial test report. Subsequent
reports are to be submitted no more than 12 months following the
previous report
• Name and address
• Statement and signature by responsible official
• Date of report
• Values for the operating limits
§§ 60.2205 and 60.2210.
• Highest recorded 3-hour
average and the lowest 3-hour average, as applicable, (or 30-day
average, if applicable) for each operating parameter recorded for
the calendar year being reported
• For each performance test conducted during the reporting period,
if any performance test is conducted, the process unit(s) tested,
the pollutant(s) tested, and the date that such performance test
was conducted
• If a performance test was not conducted during the reporting
period, a statement that the requirements of § 60.2155(a) were
met
• Documentation of periods when all qualified CISWI operators were
unavailable for more than 8 hours but less than 2 weeks
• If you are conducting performance tests once every 3 years
consistent with § 60.2155(a), the date of the last 2 performance
tests, a comparison of the emission level you achieved in the last
2 performance tests to the 75 percent emission limit threshold
required in § 60.2155(a) and a statement as to whether there have
been any operational changes since the last performance test that
could increase emissions
• Any malfunction, deviation, or continuous monitoring system out
of control periods information as specified in § 60.2210(k) through
(o)
Emission
limitation or operating limit deviation report
By August 1 of that year for
data collected during the first half of the calendar year. By
February 1 of the following year for data collected during the
second half of the calendar year
• Dates and times of
deviation
• Averaged and recorded data for those dates
• Duration and causes of each deviation and the corrective actions
taken
• Copy of operating limit monitoring data and, if any performance
test was conducted that documents emission levels, the process
unit(s) tested, the pollutant(s) tested, and the date that such
performance test was conducted
§ 60.2215 and 60.2220.
• Dates, times and causes for
monitor downtime incidents
Qualified operator
deviation notification
Within 10 days of
deviation
• Statement of cause of
deviation
• Description of efforts to have an accessible qualified
operator
§ 60.2225(a)(1).
• The date a qualified
operator will be accessible
Qualified operator
deviation status report
Every 4 weeks following
deviation
• Description of efforts to
have an accessible qualified operator
§ 60.2225(a)(2).
• The date a qualified
operator will be accessible
• Request for approval to continue operation
Qualified operator
deviation notification of resumed operation
Prior to resuming
operation
• Notification that you are
resuming operation
§ 60.2225(b).
1 This table is only a summary,
see the referenced sections of the rule for the complete
requirements.
Table 5 to Subpart CCCC of Part 60 - Emission Limitations for Incinerators That Commenced Construction After June 4, 2010, or That Commenced Reconstruction or Modification After August 7, 2013
40:8.0.1.1.1.30.209.56.21 :
Table 5 to Subpart CCCC of Part 60 - Emission Limitations for
Incinerators That Commenced Construction After June 4, 2010, or
That Commenced Reconstruction or Modification After August 7, 2013
For the air pollutant
You must meet this emission
limitation 1
Using this averaging time
2
And determining compliance
using
this method 2
Cadmium
0.0023 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meter per run)
Performance test (Method 29 at
40 CFR part 60, appendix A-8 of this part). Use ICPMS for the
analytical finish.
Carbon
monoxide
17 parts per million by dry
volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 10 at
40 CFR part 60, appendix A-4).
Dioxin/furan
(Total Mass Basis)
0.58 nanograms per dry
standard cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meters per run)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Dioxin/furan
(toxic equivalency basis)
0.13 nanograms per dry
standard cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meter per run)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Fugitive ash
Visible emissions for no more
than 5 percent of the hourly observation period
Three 1-hour observation
periods
Visible emission test (Method
22 at 40 CFR part 60, appendix A-7).
Hydrogen
chloride
0.091 parts per million by dry
volume
3-run average (For Method 26,
collect a minimum volume of 360 liters per run. For Method 26A,
collect a minimum volume of 3 dry standard cubic meters per
run)
Performance test (Method 26 or
26A at 40 CFR part 60, appendix A-8).
Lead
0.015 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meters per run)
Performance test (Method 29 of
appendix A-8 at 40 CFR part 60). Use ICPMS for the analytical
finish.
Mercury
0.00084 milligrams per dry
standard cubic meter
3-run average (collect enough
volume to meet a detection limit data quality objective of 0.03
ug/dry standard cubic meter)
Performance test (Method 29 or
30B at 40 CFR part 60, appendix A-8) or ASTM D6784-02 (Reapproved
2008). 3
Nitrogen
oxides
23 parts per million dry
volume
3-run average (for Method 7E,
1 hour minimum sample time per run)
Performance test (Method 7 or
7E at 40 CFR part 60, appendix A-4).
Particulate matter
(filterable)
18 milligrams per dry standard
cubic meter
3-run average (collect a
minimum volume of 2 dry standard cubic meters per run)
Performance test (Method 5 or
29 at 40 CFR part 60, appendix A-3 or appendix A-8 at 40 CFR part
60).
Sulfur
dioxide
11 parts per million dry
volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 6 or
6C at 40 CFR part 60, appendix A-4).
1 All emission limitations are
measured at 7 percent oxygen, dry basis at standard conditions. For
dioxins/furans, you must meet either the Total Mass Limit or the
toxic equivalency basis limit.
2 In lieu of performance testing,
you may use a CEMS or, for mercury, an integrated sorbent trap
monitoring system to demonstrate initial and continuing compliance
with an emissions limit, as long as you comply with the CEMS or
integrated sorbent trap monitoring system requirements applicable
to the specific pollutant in §§ 60.2145 and 60.2165. As prescribed
in § 60.2145(u), if you use a CEMS or an integrated sorbent trap
monitoring system to demonstrate compliance with an emissions
limit, your averaging time is a 30-day rolling average of 1-hour
arithmetic average emission concentrations.
3 Incorporated by reference, see
§ 60.17.
Table 6 to Subpart CCCC of Part 60 - Emission Limitations for Energy Recovery Units That Commenced Construction After June 4, 2010, or That Commenced Reconstruction or Modification After August 7, 2013
40:8.0.1.1.1.30.209.56.22 :
Table 6 to Subpart CCCC of Part 60 - Emission Limitations for
Energy Recovery Units That Commenced Construction After June 4,
2010, or That Commenced Reconstruction or Modification After August
7, 2013
For the air
pollutant
You must meet
this emission limitation 1
Using this
averaging time 2
And determining
compliance using this method 2
Liquid/gas
Solids
Cadmium
0.023 milligrams per dry
standard cubic meter
Biomass - 0.0014 milligrams
per dry standard cubic meter. Coal - 0.0017 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meters per run)
Performance test (Method 29 at
40 CFR part 60, appendix A-8). Use ICPMS for the analytical
finish.
Carbon
monoxide
35 parts per million dry
volume
Biomass - 240 parts per
million dry volume. Coal - 95 parts per million dry volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 10 at
40 CFR part 60, appendix A-4).
Dioxin/furans
(Total Mass Basis)
No Total Mass Basis limit,
must meet the toxic equivalency basis limit below
Biomass - 0.52 nanograms per
dry standard cubic meter. Coal - 5.1 nanograms per dry standard
cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meters)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Dioxins/furans
(toxic equivalency basis)
0.093 nanograms per dry
standard cubic meter
Biomass - 0.076 nanograms per
dry standard cubic meter. 3 Coal - 0.075 nanograms per
dry standard cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meters per run)
Performance test (Method 23 of
appendix A-7 of this part).
Fugitive ash
Visible emissions for no more
than 5 percent of the hourly observation period
Three 1-hour observation
periods
Visible emission test (Method
22 at 40 CFR part 60, appendix A-7)
Fugitive ash.
Hydrogen
chloride
14 parts per million dry
volume
Biomass - 0.20 parts per
million dry volume. Coal - 58 parts per million dry volume
3-run average (For Method 26,
collect a minimum volume of 360 liters per run. For Method 26A,
collect a minimum volume of 3 dry standard cubic meters per
run)
Performance test (Method 26 or
26A at 40 CFR part 60, appendix A-8).
Lead
0.096 milligrams per dry
standard cubic meter
Biomass - 0.014 milligrams per
dry standard cubic meter. Coal - 0.057 milligrams per dry standard
cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meters per run)
Performance test (Method 29 at
40 CFR part 60, appendix A-8). Use ICPMS for the analytical
finish.
Mercury
0.00056 milligrams per dry
standard cubic meter
Biomass - 0.0022 milligrams
per dry standard cubic meter. Coal - 0.013 milligrams per dry
standard cubic meter
3-run average (collect enough
volume to meet an in-stack detection limit data quality objective
of 0.03 ug/dscm)
Performance test (Method 29 or
30B at 40 CFR part 60, appendix A-8) or ASTM D6784-02 (Reapproved
2008). 3
Nitrogen
oxides
76 parts per million dry
volume
Biomass - 290 parts per
million dry volume. Coal - 460 parts per million dry volume
3-run average (for Method 7E,
1 hour minimum sample time per run)
Performance test (Method 7 or
7E at 40 CFR part 60, appendix A-4).
Particulate matter
(filterable)
110 milligrams per dry
standard cubic meter
Biomass - 5.1 milligrams per
dry standard cubic meter. Coal - 130 milligrams per dry standard
cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meter per run)
Performance test (Method 5 or
29 at 40 CFR part 60, appendix A-3 or appendix A-8).
Sulfur
dioxide
720 parts per million dry
volume
Biomass - 7.3 parts per
million dry volume. Coal - 850 parts per million dry volume
3-run average (for Method 6,
collect a minimum of 60 liters, for Method 6C, 1 hour minimum
sample time per run)
Performance test (Method 6 or
6C at 40 CFR part 60, appendix A-4).
1 All emission limitations are
measured at 7 percent oxygen, dry basis at standard conditions. For
dioxins/furans, you must meet either the Total Mass Basis limit or
the toxic equivalency basis limit.
2 In lieu of performance testing,
you may use a CEMS or, for mercury, an integrated sorbent trap
monitoring system to demonstrate initial and continuing compliance
with an emissions limit, as long as you comply with the CEMS or
integrated sorbent trap monitoring system requirements applicable
to the specific pollutant in §§ 60.2145 and 60.2165. As prescribed
in § 60.2145(u), if you use a CEMS or an integrated sorbent trap
monitoring system to demonstrate compliance with an emissions
limit, your averaging time is a 30-day rolling average of 1-hour
arithmetic average emission concentrations.
3 Incorporated by reference, see
§ 60.17.
[85 FR 63404, Oct. 7, 2020]
Table 7 to Subpart CCCC of Part 60 - Emission Limitations for Waste-Burning Kilns That Commenced Construction After June 4, 2010, or Reconstruction or Modification After August 7, 2013
40:8.0.1.1.1.30.209.56.23 :
Table 7 to Subpart CCCC of Part 60 - Emission Limitations for
Waste-Burning Kilns That Commenced Construction After June 4, 2010,
or Reconstruction or Modification After August 7, 2013
For the air pollutant
You must meet this emission
limitation 1
Using this averaging time
2
And determining compliance
using this method 2, 3
Cadmium
0.0014 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meters per run)
Performance test (Method 29 at
40 CFR part 60, appendix A-8). Use ICPMS for the analytical
finish.
Carbon
monoxide
90 (long kilns)/190
(preheater/precalciner) parts per million dry volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 10 at
40 CFR part 60, appendix A-4).
Dioxins/furans
(total mass basis)
0.51 nanograms per dry
standard cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meters per run)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Dioxins/furans
(toxic equivalency basis)
0.075 nanograms per dry
standard cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meters)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Hydrogen
chloride
3.0 parts per million dry
volume
3-run average (1 hour minimum
sample time per run) or 30-day rolling average if HCl CEMS is being
used
If a wet scrubber or dry
scrubber is used, performance test (Method 321 at 40 CFR part 63,
appendix A). If a wet scrubber or dry scrubber is not used, HCl
CEMS as specified in § 60.2145(j).
Lead
0.014 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meters)
Performance test (Method 29 at
40 CFR part 60, appendix A-8). Use ICPMS for the analytical
finish.
Mercury
0.0037 milligrams per dry
standard cubic meter. Or 21 pounds/million tons of clinker
3
30-day rolling average
Mercury CEMS or integrated
sorbent trap monitoring system (performance specification 12A or
12B, respectively, of appendix B and procedure 5 of appendix F of
this part), as specified in § 60.2145(j).
Nitrogen
oxides
200 parts per million dry
volume
30-day rolling average
Nitrogen oxides CEMS
(performance specification 2 of appendix B and procedure 1 of
appendix F of this part).
Particulate matter
(filterable)
4.9 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 2 dry standard cubic meters)
Performance test (Method 5 or
29 at 40 CFR part 60, appendix A-3 or appendix-8).
Sulfur
dioxide
28 parts per million dry
volume
30-day rolling average
Sulfur dioxide CEMS
(performance specification 2 of appendix B and procedure 1 of
appendix F of this part).
1 All emission limitations are
measured at 7 percent oxygen (except for CEMS and integrated
sorbent trap monitoring system data during startup and shutdown),
dry basis at standard conditions. For dioxins/furans, you must meet
either the Total Mass Basis limit or the toxic equivalency basis
limit.
2 In lieu of performance testing,
you may use a CEMS or, for mercury, an integrated sorbent trap
monitoring system, to demonstrate initial and continuing compliance
with an emissions limit, as long as you comply with the CEMS or
integrated sorbent trap monitoring system requirements applicable
to the specific pollutant in §§ 60.2145 and 60.2165. As prescribed
in § 60.2145(u), if you use a CEMS or integrated sorbent trap
monitoring system to demonstrate compliance with an emissions
limit, your averaging time is a 30-day rolling average of 1-hour
arithmetic average emission concentrations.
3 Alkali bypass and in-line coal
mill stacks are subject to performance testing only, as specified
in § 60.2145(y)(3). They are not subject to the CEMS, integrated
sorbent trap monitoring system, or CPMS requirements that otherwise
may apply to the main kiln exhaust.
[85 FR 63405, Oct. 7, 2020]
Table 8 to Subpart CCCC of Part 60 - Emission Limitations for Small, Remote Incinerators That Commenced Construction After June 4, 2010, or That Commenced Reconstruction or Modification After August 7, 2013
40:8.0.1.1.1.30.209.56.24 :
Table 8 to Subpart CCCC of Part 60 - Emission Limitations for
Small, Remote Incinerators That Commenced Construction After June
4, 2010, or That Commenced Reconstruction or Modification After
August 7, 2013
For the air pollutant
You must meet this
emission limitation 1
Using this averaging time
2
And determining
compliance
using this method 2
Cadmium
0.67 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 29 at
40 CFR part 60, appendix A-8).
Carbon
monoxide
13 parts per million dry
volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 10 at
40 CFR part 60, appendix A-4).
Dioxins/furans
(total mass basis)
1,800 nanograms per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Dioxins/furans
(toxic equivalency basis)
31 nanograms per dry standard
cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Fugitive ash
Visible emissions for no more
than 5 percent of the hourly observation period
Three 1-hour observation
periods
Visible emissions test (Method
22 at 40 CFR part 60, appendix A-7).
Hydrogen
chloride
200 parts per million by dry
volume
3-run average (For Method 26,
collect a minimum volume of 60 liters per run. For Method 26A,
collect a minimum volume of 1 dry standard cubic meter per
run)
Performance test (Method 26 or
26A at 40 CFR part 60, appendix A-8).
Lead
2.0 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters)
Performance test (Method 29 at
40 CFR part 60, appendix A-8). Use ICPMS for the analytical
finish.
Mercury
0.0035 milligrams per dry
standard cubic meter
3-run average (For Method 29
and ASTM D6784-02 (Reapproved 2008) 2, collect a minimum
volume of 2 dry standard cubic meters per run. For Method 30B,
collect a minimum volume as specified in Method 30B at 40 CFR part
60, appendix A)
Performance test (Method 29 or
30B at 40 CFR part 60, appendix A-8) or ASTM D6784-02 (Reapproved
2008). 3
Nitrogen
oxides
170 parts per million dry
volume
3-run average (for Method 7E,
1 hour minimum sample time per run)
Performance test (Method 7 or
7E at 40 CFR part 60, appendix A-4).
Particulate matter
(filterable)
270 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters)
Performance test (Method 5 or
29 at 40 CFR part 60, appendix A-3 or appendix A-8).
Sulfur
dioxide
1.2 parts per million dry
volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 6 or
6c at 40 CFR part 60, appendix A-4).
1 All emission limitations are
measured at 7 percent oxygen, dry basis at standard conditions. For
dioxins/furans, you must meet either the Total Mass Basis limit or
the toxic equivalency basis limit.
2 In lieu of performance testing,
you may use a CEMS or, for mercury, an integrated sorbent trap
monitoring system to demonstrate initial and continuing compliance
with an emissions limit, as long as you comply with the CEMS or
integrated sorbent trap monitoring system requirements applicable
to the specific pollutant in §§ 60.2145 and 60.2165. As prescribed
in § 60.2145(u), if you use a CEMS or an integrated sorbent trap
monitoring system to demonstrate compliance with an emissions
limit, your averaging time is a 30-day rolling average of 1-hour
arithmetic average emission concentrations.
3 Incorporated by reference, see
§ 60.17.
Table 1 to Subpart DDDD of Part 60 - Model Rule - Increments of Progress and Compliance Schedules
40:8.0.1.1.1.31.224.80.25 :
Table 1 to Subpart DDDD of Part 60 - Model Rule - Increments of
Progress and Compliance Schedules
Comply with these increments
of progress
By these dates
1
Increment 1-Submit
final control plan
(Dates to be specified in
state plan).
Increment 2-Final
compliance
(Dates to be specified in
state plan). 2
1 Site-specific schedules can be
used at the discretion of the state.
2 The date can be no later than 3
years after the effective date of state plan approval or December
1, 2005 for CISWIs that commenced construction on or before
November 30, 1999. The date can be no later than 3 years after the
effective date of approval of a revised state plan or February 7,
2018, for CISWIs that commenced construction on or before June 4,
2010.
Table 2 to Subpart DDDD of Part 60 - Model Rule - Emission Limitations That Apply to Incinerators Before [Date To Be Specified in State Plan] 1
40:8.0.1.1.1.31.224.80.26 :
Table 2 to Subpart DDDD of Part 60 - Model Rule - Emission
Limitations That Apply to Incinerators Before [Date To Be Specified
in State Plan] 1
For the air pollutant
You must meet this
emission limitation 2
Using this averaging time
3
And determining compliance
using this method 3
Cadmium
0.004 milligrams per dry
standard cubic meter
3-run average (1 hour minimum
sample time per run)
Performance test (Method 29 of
appendix A of this part).
Carbon
monoxide
157 parts per million by dry
volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 10,
10A, or 10B, of appendix A of this part).
Dioxins/furans
(toxic equivalency basis)
0.41 nanograms per dry
standard cubic meter
3-run average (1 hour minimum
sample time per run)
Performance test (Method 23 of
appendix A of this part).
Hydrogen
chloride
62 parts per million by dry
volume
3-run average (For Method 26,
collect a minimum volume of 120 liters per run. For Method 26A,
collect a minimum volume of 1 dry standard cubic meter per
run)
Performance test (Method 26 or
26A at 40 CFR part 60, appendix A-8).
Lead
0.04 milligrams per dry
standard cubic meter
3-run average (1 hour minimum
sample time per run)
Performance test (Method 29 of
appendix A of this part).
Mercury
0.47 milligrams per dry
standard cubic meter
3-run average (1 hour minimum
sample time per run)
Performance test (Method 29 or
30B at 40 CFR part 60, appendix A-8) or ASTM D6784-02 (Reapproved
2008). 4
Opacity
10 percent
Three 1-hour blocks consisting
of ten 6-minute average opacity values
Performance test (Method 9 at
40 CFR part 60, appendix A-4).
Nitrogen
oxides
388 parts per million by dry
volume
3-run average (1 hour minimum
sample time per run)
Performance test (Methods 7 or
7E at 40 CFR part 60, appendix A-4).
Particulate
matter
70 milligrams per dry standard
cubic meter
3-run average (1 hour minimum
sample time per run)
Performance test (Method 5 or
29 of appendix A of this part).
Sulfur
dioxide
20 parts per million by dry
volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 6 or
6c of appendix A of this part).
1 Applies only to incinerators
subject to the CISWI standards through a state plan or the Federal
plan prior to June 4, 2010. The date specified in the state plan
can be no later than 3 years after the effective date of approval
of a revised state plan or February 7, 2018.
2 All emission limitations
(except for opacity) are measured at 7 percent oxygen, dry basis at
standard conditions.
3 In lieu of performance testing,
you may use a CEMS or, for mercury, an integrated sorbent trap
monitoring system, to demonstrate initial and continuing compliance
with an emissions limit, as long as you comply with the CEMS or
integrated sorbent trap monitoring system requirements applicable
to the specific pollutant in §§ 60.2710 and 60.2730. As prescribed
in § 60.2710(u), if you use a CEMS or integrated sorbent trap
monitoring system to demonstrate compliance with an emissions
limit, your averaging time is a 30-day rolling average of 1-hour
arithmetic average emission concentrations.
4 Incorporated by reference, see
§ 60.17.
Table 3 to Subpart DDDD of Part 60 - Model Rule - Operating Limits for Wet Scrubbers
40:8.0.1.1.1.31.224.80.27 :
Table 3 to Subpart DDDD of Part 60 - Model Rule - Operating Limits
for Wet Scrubbers
For these
operating
parameters
You must
establish these operating limits
And monitor using
these minimum frequencies
Data
measurement
Data
recording
Averaging time
Charge rate
Maximum charge rate
Continuous
Every hour
Daily (batch units). 3-hour
rolling (continuous and intermittent units). 1
Pressure drop
across the wet scrubber or amperage to wet scrubber
Minimum pressure drop or
amperage
Continuous
Every 15 minutes
3-hour rolling.
1
Scrubber liquor
flow rate
Minimum flow rate
Continuous
Every 15 minutes
3-hour rolling.
1
Scrubber liquor
pH
Minimum pH
Continuous
Every 15 minutes
3-hour rolling.
1
1 Calculated each hour as the
average of the previous 3 operating hours.
Table 4 to Subpart DDDD of Part 60 - Model Rule - Toxic Equivalency Factors
40:8.0.1.1.1.31.224.80.28 :
Table 4 to Subpart DDDD of Part 60 - Model Rule - Toxic Equivalency
Factors
Dioxin/furan isomer
Toxic
equivalency
factor
2,3,7,8-tetrachlorinated dibenzo-p-dioxin
1
1,2,3,7,8-pentachlorinated dibenzo-p-dioxin
0.5
1,2,3,4,7,8-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,7,8,9-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,6,7,8-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,4,6,7,8-heptachlorinated dibenzo-p-dioxin
0.01
octachlorinated
dibenzo-p-dioxin
0.001
2,3,7,8-tetrachlorinated dibenzofuran
0.1
2,3,4,7,8-pentachlorinated dibenzofuran
0.5
1,2,3,7,8-pentachlorinated dibenzofuran
0.05
1,2,3,4,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,6,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,7,8,9-hexachlorinated dibenzofuran
0.1
2,3,4,6,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,4,6,7,8-heptachlorinated dibenzofuran
0.01
1,2,3,4,7,8,9-heptachlorinated dibenzofuran
0.01
octachlorinated
dibenzofuran
0.001
Table 5 to Subpart DDDD of Part 60 - Model Rule - Summary of Reporting Requirements 1
40:8.0.1.1.1.31.224.80.29 :
Table 5 to Subpart DDDD of Part 60 - Model Rule - Summary of
Reporting Requirements 1
Report
Due date
Contents
Reference
Waste Management
Plan
No later than the date
specified in table 1 for submittal of the final control plan
• Waste management plan
§ 60.2755.
Initial Test
Report
No later than 60 days
following the initial performance test
• Complete test report for the
initial performance test
• The values for the site-specific operating limits
• Installation of bag leak detection systems for fabric
filters
§ 60.2760.
Annual report
No later than 12 months
following the submission of the initial test report. Subsequent
reports are to be submitted no more than 12 months following the
previous report
• Name and address
• Statement and signature by responsible official
• Date of report
• Values for the operating limits
• Highest recorded 3-hour average and the lowest 3-hour average, as
applicable, (or 30-day average, if applicable) for each operating
parameter recorded for the calendar year being reported
• If a performance test was conducted during the reporting period,
the results of the test
• If a performance test was not conducted during the reporting
period, a statement that the requirements of § 60.2720(a) were
met
• Documentation of periods when all qualified CISWI operators were
unavailable for more than 8 hours but less than 2 weeks
• If you are conducting performance tests once every 3 years
consistent with § 60.2720(a), the date of the last 2 performance
tests, a comparison of the emission level you achieved in the last
2 performance tests to the 75 percent emission limit threshold
required in § 60.2720(a) and a statement as to whether there have
been any operational changes since the last performance test that
could increase emissions
• Any malfunction, deviation, or continuous monitoring system out
of control periods information as specified in § 60.2770(k) through
(o)
• Fuel input information for energy recovery unit subcategory
verification as specified in § 60.2770(p)
§§ 60.2765 and 60.2770.
Emission
limitation or operating limit deviation report
By August 1 of that year for
data collected during the first half of the calendar year. By
February 1 of the following year for data collected during the
second half of the calendar year
• Dates and times of
deviation
• Averaged and recorded data for those dates
• Duration and causes of each deviation and the corrective actions
taken
• Copy of operating limit monitoring data and any test reports
• Dates, times and causes for monitor downtime incidents
§ 60.2775 and 60.2780.
Qualified Operator
Deviation Notification
Within 10 days of
deviation
• Statement of cause of
deviation
• Description of efforts to have an accessible qualified
operator
• The date a qualified operator will be accessible
§ 60.2785(a)(1).
Qualified Operator
Deviation Status Report
Every 4 weeks following
deviation
• Description of efforts to
have an accessible qualified operator
• The date a qualified operator will be accessible
• Request for approval to continue operation
§ 60.2785(a)(2).
Qualified Operator
Deviation Notification of Resumed Operation
Prior to resuming
operation
• Notification that you are
resuming operation
§ 60.2785(b).
1 This table is only a summary,
see the referenced sections of the rule for the complete
requirements.
Table 6 to Subpart DDDD of Part 60 - Model Rule - Emission Limitations That Apply to Incinerators on and After [Date To Be Specified in State Plan] 1
40:8.0.1.1.1.31.224.80.30 :
Table 6 to Subpart DDDD of Part 60 - Model Rule - Emission
Limitations That Apply to Incinerators on and After [Date To Be
Specified in State Plan] 1
For the air pollutant
You must meet this
emission limitation 2
Using this averaging time
3
And determining compliance
using this method 3
Cadmium
0.0026 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 2 dry standard cubic meters)
Performance test (Method 29 at
40 CFR part 60, appendix A-8). Use ICPMS for the analytical
finish.
Carbon
monoxide
17 parts per million dry
volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 10 at
40 CFR part 60, appendix A-4).
Dioxins/furans
(total mass basis)
4.6 nanograms per dry standard
cubic meter
3-run average (collect a
minimum volume of 2 dry standard cubic meters)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Dioxins/furans
(toxic equivalency basis)
0.13 nanograms per dry
standard cubic meter
3-run average (collect a
minimum volume of 2 dry standard cubic meters)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Hydrogen
chloride
29 parts per million dry
volume
3-run average (For Method 26,
collect a minimum volume of 60 liters per run. For Method 26A,
collect a minimum volume of 1 dry standard cubic meter per
run)
Performance test (Method 26 or
26A at 40 CFR part 60, appendix A-8).
Lead
0.015 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 2 dry standard cubic meters)
Performance test (Method 29 at
40 CFR part 60, appendix A-8). Use ICPMS for the analytical
finish.
Mercury
0.0048 milligrams per dry
standard cubic meter
3-run average (For Method 29
an ASTM D6784-02 (Reapproved 2008), 4 collect a minimum
volume of 2 dry standard cubic meters per run. For Method 30B,
collect a minimum sample as specified in Method 30B at 40 CFR part
60, appendix A)
Performance test (Method 29 or
30B at 40 CFR part 60, appendix A-8) or ASTM D6784-02 (Reapproved
2008). 4
Nitrogen
oxides
53 parts per million dry
volume
3-run average (for Method 7E,
1 hour minimum sample time per run)
Performance test (Method 7 or
7E at 40 CFR part 60, appendix A-4).
Particulate matter
filterable
34 milligrams per dry standard
cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meter)
Performance test (Method 5 or
29 at 40 CFR part 60, appendix A-3 or appendix A-8).
Sulfur
dioxide
11 parts per million dry
volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 6 or
6c at 40 CFR part 60, appendix A-4).
Fugitive ash
Visible emissions for no more
than 5% of the hourly observation period
Three 1-hour observation
periods
Visible emission test (Method
22 at 40 CFR part 60, appendix A-7).
1 The date specified in the state
plan can be no later than 3 years after the effective date of
approval of a revised state plan or February 7, 2018.
2 All emission limitations are
measured at 7 percent oxygen, dry basis at standard conditions. For
dioxins/furans, you must meet either the total mass basis limit or
the toxic equivalency basis limit.
3 In lieu of performance testing,
you may use a CEMS or, for mercury, an integrated sorbent trap
monitoring system, to demonstrate initial and continuing compliance
with an emissions limit, as long as you comply with the CEMS or
integrated sorbent trap monitoring system requirements applicable
to the specific pollutant in §§ 60.2710 and 60.2730. As prescribed
in § 60.2710(u), if you use a CEMS or integrated sorbent trap
monitoring system to demonstrate compliance with an emissions
limit, your averaging time is a 30-day rolling average of 1-hour
arithmetic average emission concentrations.
4 Incorporated by reference, see
§ 60.17.
Table 7 to Subpart DDDD of Part 60 - Model Rule - Emission Limitations That Apply to Energy Recovery Units After May 20, 2011
40:8.0.1.1.1.31.224.80.31 :
Table 7 to Subpart DDDD of Part 60 - Model Rule - Emission
Limitations That Apply to Energy Recovery Units After May 20, 2011
[Date to be specified in state plan]
1
For the air
pollutant
You must meet
this emission limitation 2
Using this
averaging time 3
And determining
compliance using this method 3
Liquid/gas
Solids
Cadmium
0.023 milligrams per dry
standard cubic meter
Biomass - 0.0014 milligrams
per dry standard cubic meter. Coal - 0.0017 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 2 dry standard cubic meters)
Performance test (Method 29 at
40 CFR part 60, appendix A-8). Use ICPMS for the analytical
finish.
Carbon
monoxide
35 parts per million dry
volume
Biomass - 260 parts per
million dry volume. Coal - 95 parts per million dry volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 10 at
40 CFR part 60, appendix A-4).
Dioxins/furans
(total mass basis)
2.9 nanograms per dry standard
cubic meter
Biomass - 0.52 nanograms per
dry standard cubic meter. Coal - 5.1 nanograms per dry standard
cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meter)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Dioxins/furans
(toxic equivalency basis)
0.32 nanograms per dry
standard cubic meter
Biomass - 0.12 nanograms per
dry standard cubic meter. Coal - 0.075 nanograms per dry standard
cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meters)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Hydrogen
chloride
14 parts per million dry
volume
Biomass - 0.20 parts per
million dry volume. Coal - 58 parts per million dry volume
3-run average (for Method 26,
collect a minimum of 120 liters; for Method 26A, collect a minimum
volume of 1 dry standard cubic meter)
Performance test (Method 26 or
26A at 40 CFR part 60, appendix A-8).
Lead
0.096 milligrams per dry
standard cubic meter
Biomass - 0.014 milligrams per
dry standard cubic meter. Coal - 0.057 milligrams per dry standard
cubic meter
3-run average (collect a
minimum volume of 2 dry standard cubic meters)
Performance test (Method 29 at
40 CFR part 60, appendix A-8). Use ICPMS for the analytical
finish.
Mercury
0.0024 milligrams per dry
standard cubic meter
Biomass - 0.0022 milligrams
per dry standard cubic meter. Coal - 0.013 milligrams per dry
standard cubic meter
3-run average (For Method 29
and ASTM D6784-02 (Reapproved 2008) 4, collect a minimum
volume of 2 dry standard cubic meters per run. For Method 30B,
collect a minimum sample as specified in Method 30B at 40 CFR part
60, appendix A)
Performance test (Method 29 or
30B at 40 CFR part 60, appendix A-8) or ASTM D6784-02 (Reapproved
2008). 4
Nitrogen
oxides
76 parts per million dry
volume
Biomass - 290 parts per
million dry volume. Coal - 460 parts per million dry volume
3-run average (for Method 7E,
1 hour minimum sample time per run)
Performance test (Method 7 or
7E at 40 CFR part 60, appendix A-4).
Particulate matter
filterable
110 milligrams per dry
standard cubic meter
Biomass - 11 milligrams per
dry standard cubic meter. Coal - 130 milligrams per dry standard
cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meter)
Performance test (Method 5 or
29 at 40 CFR part 60, appendix A-3 or appendix A-8).
Sulfur
dioxide
720 parts per million dry
volume
Biomass - 7.3 parts per
million dry volume. Coal - 850 parts per million dry volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 6 or
6c at 40 CFR part 60, appendix A-4).
Fugitive ash
Visible emissions for no more
than 5 percent of the hourly observation period
Visible emissions for no more
than 5 percent of the hourly observation period
Three 1-hour observation
periods
Visible emission test (Method
22 at 40 CFR part 60, appendix A-7).
1 The date specified in the state
plan can be no later than 3 years after the effective date of
approval of a revised state plan or February 7, 2018.
2 All emission limitations
(except for opacity) are measured at 7 percent oxygen, dry basis at
standard conditions. For dioxins/furans, you must meet either the
total mass basis limit or the toxic equivalency basis limit.
3 In lieu of performance testing,
you may use a CEMS or, for mercury, an integrated sorbent trap
monitoring system, to demonstrate initial and continuing compliance
with an emissions limit, as long as you comply with the CEMS or
integrated sorbent trap monitoring system requirements applicable
to the specific pollutant in §§ 60.2710 and 60.2730. As prescribed
in § 60.2710(u), if you use a CEMS or integrated sorbent trap
monitoring system to demonstrate compliance with an emissions
limit, your averaging time is a 30-day rolling average of 1-hour
arithmetic average emission concentrations.
4 Incorporated by reference, see
§ 60.17.
[85 FR 63406, Oct. 7, 2020]
Table 8 to Subpart DDDD of Part 60 - Model Rule - Emission Limitations That Apply to Waste-Burning Kilns After May 20, 2011
40:8.0.1.1.1.31.224.80.32 :
Table 8 to Subpart DDDD of Part 60 - Model Rule - Emission
Limitations That Apply to Waste-Burning Kilns After May 20, 2011
[Date to be specified in state plan]
1
For the air pollutant
You must meet this emission
limitation 2
Using this averaging time
3
And determining compliance
using this method 3 4
Cadmium
0.0014 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 2 dry standard cubic meters)
Performance test (Method 29 at
40 CFR part 60, appendix A-8).
Carbon
monoxide
110 (long kilns)/790
(preheater/precalciner) parts per million dry volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 10 at
40 CFR part 60, appendix A-4).
Dioxins/furans
(total mass basis)
1.3 nanograms per dry standard
cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meters)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Dioxins/furans
(toxic equivalency basis)
0.075 nanograms per dry
standard cubic meter
3-run average (collect a
minimum volume of 4 dry standard cubic meters)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Hydrogen
chloride
3.0 parts per million dry
volume
3-run average (collect a
minimum volume of 1 dry standard cubic meter), or 30-day rolling
average if HCl CEMS is being used
If a wet scrubber or dry
scrubber is used, performance test (Method 321 at 40 CFR part 63,
appendix A of this part). If a wet scrubber or dry scrubber is not
used, HCl CEMS as specified in § 60.2710(j).
Lead
0.014 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 2 dry standard cubic meters)
Performance test (Method 29 at
40 CFR part 60, appendix A-8).
Mercury
0.011 milligrams per dry
standard cubic meter. Or 58 pounds/million tons of clinker
30-day rolling average
Mercury CEMS or integrated
sorbent trap monitoring system (performance specification 12A or
12B, respectively, of appendix B and procedure 5 of appendix F of
this part), as specified in § 60.2710(j).
Nitrogen
oxides
630 parts per million dry
volume
3-run average (for Method 7E,
1 hour minimum sample time per run)
Performance test (Method 7 or
7E at 40 CFR part 60, appendix A-4).
Particulate matter
filterable
13.5 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meter)
Performance test (Method 5 or
29 at 40 CFR part 60, appendix A-3 or appendix-8).
Sulfur
dioxide
600 parts per million dry
volume
3-run average (for Method 6,
collect a minimum of 20 liters; for Method 6C, 1 hour minimum
sample time per run)
Performance test (Method 6 or
6c at 40 CFR part 60, appendix A-4).
1 The date specified in the state
plan can be no later than 3 years after the effective date of
approval of a revised state plan or February 7, 2018.
2 All emission limitations are
measured at 7 percent oxygen (except for CEMS and integrated
sorbent trap monitoring system data during startup and shutdown),
dry basis at standard conditions. For dioxins/furans, you must meet
either the total mass basis limit or the toxic equivalency basis
limit.
3 In lieu of performance testing,
you may use a CEMS or, for mercury, an integrated sorbent trap
monitoring system, to demonstrate initial and continuing compliance
with an emissions limit, as long as you comply with the CEMS or
integrated sorbent trap monitoring system requirements applicable
to the specific pollutant in §§ 60.2710 and 60.2730. As prescribed
in § 60.2710(u), if you use a CEMS or integrated sorbent trap
monitoring system to demonstrate compliance with an emissions
limit, your averaging time is a 30-day rolling average of 1-hour
arithmetic average emission concentrations.
4 Alkali bypass and in-line coal
mill stacks are subject to performance testing only, as specified
in § 60.2710(y)(3). They are not subject to the CEMS, integrated
sorbent trap monitoring system, or CPMS requirements that otherwise
may apply to the main kiln exhaust.
[85 FR 63407, Oct. 7, 2020]
Table 9 to Subpart DDDD of Part 60 - Model Rule - Emission Limitations That Apply to Small, Remote Incinerators After May 20, 2011 [Date To Be Specified in State Plan] 1
40:8.0.1.1.1.31.224.80.33 :
Table 9 to Subpart DDDD of Part 60 - Model Rule - Emission
Limitations That Apply to Small, Remote Incinerators After May 20,
2011 [Date To Be Specified in State Plan] 1
For the air pollutant
You must meet this
emission limitation 2
Using this averaging time
3
And determining compliance
using this method 3
Cadmium
0.95 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 29 at
40 CFR part 60, appendix A-8).
Carbon
monoxide
64 parts per million dry
volume
3-run average (1 hour minimum
sample time per run)
Performance test (Method 10 at
40 CFR part 60, appendix A-4).
Dioxins/furans
(total mass basis)
4,400 nanograms per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Dioxins/furans
(toxic equivalency basis)
180 nanograms per dry standard
cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Fugitive ash
Visible emissions for no more
than 5 percent of the hourly observation period
Three 1-hour observation
periods
Visible emissions test (Method
22 at 40 CFR part 60, appendix A-7).
Hydrogen
chloride
300 parts per million dry
volume
3-run average (For Method 26,
collect a minimum volume of 120 liters per run. For Method 26A,
collect a minimum volume of 1 dry standard cubic meter per
run)
Performance test (Method 26 or
26A at 40 CFR part 60, appendix A-8).
Lead
2.1 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters)
Performance test (Method 29 at
40 CFR part 60, appendix A-8). Use ICPMS for the analytical
finish.
Mercury
0.0053 milligrams per dry
standard cubic meter
3-run average (For Method 29
and ASTM D6784-02 (Reapproved 2008), 3 collect a minimum
volume of 2 dry standard cubic meters per run. For Method 30B,
collect a minimum sample as specified in Method 30B at 40 CFR part
60, appendix A)
Performance test (Method 29 or
30B at 40 CFR part 60, appendix A-8) or ASTM D6784-02 (Reapproved
2008). 4
Nitrogen
oxides
190 parts per million dry
volume
3-run average (for Method 7E,
1 hour minimum sample time per run)
Performance test (Method 7 or
7E at 40 CFR part 60, appendix A-4).
Particulate matter
(filterable)
270 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters)
Performance test (Method 5 or
29 at 40 CFR part 60, appendix A-3 or appendix A-8).
Sulfur
dioxide
150 parts per million dry
volume
3-run average (for Method 6,
collect a minimum of 20 liters per run; for Method 6C, 1 hour
minimum sample time per run)
Performance test (Method 6 or
6c at 40 CFR part 60, appendix A-4).
1 The date specified in the state
plan can be no later than 3 years after the effective date of
approval of a revised state plan or February 7, 2018.
2 All emission limitations
(except for opacity) are measured at 7 percent oxygen, dry basis at
standard conditions. For dioxins/furans, you must meet either the
total mass basis limit or the toxic equivalency basis limit.
3 In lieu of performance testing,
you may use a CEMS or, for mercury, an integrated sorbent trap
monitoring system, to demonstrate initial and continuing compliance
with an emissions limit, as long as you comply with the CEMS or
integrated sorbent trap monitoring system requirements applicable
to the specific pollutant in §§ 60.2710 and 60.2730. As prescribed
in § 60.2710(u), if you use a CEMS or integrated sorbent trap
monitoring system to demonstrate compliance with an emissions
limit, your averaging time is a 30-day rolling average of 1-hour
arithmetic average emission concentrations.
4 Incorporated by reference, see
§ 60.17.
Table 1 to Subpart EEEE of Part 60 - Emission Limitations
40:8.0.1.1.1.32.240.65.34 :
Table 1 to Subpart EEEE of Part 60 - Emission Limitations
As stated in § 60.2915, you must comply with the following:
For the air pollutant
You must meet this
emission
limitation a
Using this averaging
time
And determining
compliance using this method
1. Cadmium
18 micrograms per dry standard
cubic meter
3-run average (1 hour minimum
sample time per run)
Method 29 of appendix A of
this part.
2. Carbon
monoxide
40 parts per million by dry
volume
3-run average (1 hour minimum
sample time per run during performance test), and 12-hour rolling
averages measured using CEMS. b
Method 10, 10A, or 10B of
appendix A of this part and CEMS.
3. Dioxins/furans
(total basis)
33 nanograms per dry standard
cubic meter
3-run average (1 hour minimum
sample meter time per run)
Method 23 of appendix A of
this part.
4. Hydrogen
chloride
15 parts per million by dry
volume
3-run average (1 hour minimum
sample time per run)
Method 26A of appendix A of
this part.
5. Lead
226 micrograms per dry
standard cubic meter
3-run average (1 hour minimum
sample time per run)
Method 29 of appendix A of
this part.
6. Mercury
74 micrograms per dry standard
cubic meter
3-run average (1 hour minimum
sample time per run)
Method 29 of appendix A of
this part.
7. Opacity
10 percent
6-minute average (observe over
three 1-hour test runs; i.e., thirty 6-minute averages)
Method 9 of appendix A of this
part.
8. Oxides of
nitrogen
103 parts per million by dry
volume
3-run average (1 hour minimum
sample time per run)
Method 7, 7A, 7C, 7D, or 7E of
appendix A of this part, or ANSI/ASME PTC 19.10-1981 (IBR, see §
60.17(h)) in lieu of Methods 7 and 7C only.
9. Particulate
matter
0.013 grains per dry standard
cubic foot
3-run average (1 hour minimum
sample time per run)
Method 5 or 29 of appendix A
of this part.
10. Sulfur
dioxide
3.1 parts per million by dry
volume
3-run average (1 hour minimum
sample time per run)
Method 6 or 6C of appendix A
of this part, or ANSI/ASME PTC 19.10-1981 (IBR, see § 60.17(h)) in
lieu of Method 6 only.
a All emission limitations
(except for opacity) are measured at 7 percent oxygen, dry basis at
standard conditions.
b Calculated each hour as the
average of the previous 12 operating hours.
Table 2 to Subpart EEEE of Part 60 - Operating Limits for Incinerators and Wet Scrubbers
40:8.0.1.1.1.32.240.65.35 :
Table 2 to Subpart EEEE of Part 60 - Operating Limits for
Incinerators and Wet Scrubbers
As stated in § 60.2916, you must comply with the following:
For these
operating
parameters
You must
establish these operating limits
And monitoring
using these minimum frequencies
Data measurement
Data recording
Averaging time
1. Charge
rate
Maximum charge rate
Continuous
Every hour
Daily for batch units. 3-hour
rolling for continuous and intermittent units a.
2. Pressure drop
across the wet scrubber or amperage to wet scrubber
Minimum pressure drop or
amperage
Continuous
Every 15 minutes
3-hour rolling
a.
3. Scrubber liquor
flow rate
Minimum flow rate
Continuous
Every 15 minutes
3-hour rolling
a.
4. Scrubber liquor
pH
Minimum pH
Continuous
Every 15 minutes
3-hour rolling
a.
a Calculated each hour as the
average of the previous 3 operating hours.
Table 3 to Subpart EEEE of Part 60 - Requirements for Continuous Emission Monitoring Systems (CEMS)
40:8.0.1.1.1.32.240.65.36 :
Table 3 to Subpart EEEE of Part 60 - Requirements for Continuous
Emission Monitoring Systems (CEMS)
As stated in § 60.2940, you must comply with the following:
For the following
pollutants
Use the following span values
for your CEMS
Use the following performance
specifications (P.S.) in appendix B of this part for your CEMS
If needed to meet minimum
data requirements, use the following alternate methods in appendix
A of this part to collect data
1. Carbon
Monoxide
125 percent of the maximum
hourly potential carbon monoxide emissions of the waste combustion
unit
P.S.4A
Method 10.
2. Oxygen
25 percent oxygen
P.S.3
Method 3A or 3B, or ANSI/ASME
PTC 19.10-1981 (IBR, see § 60.17(h)) in lieu of Method 3B
only.
Table 4 to Subpart EEEE of Part 60 - Summary of Reporting Requirements
40:8.0.1.1.1.32.240.65.37 :
Table 4 to Subpart EEEE of Part 60 - Summary of Reporting
Requirements
As stated in § 60.2951, you must comply with the following:
Report
Due date
Contents
Reference
1. Preconstruction
report
a. Prior to commencing
construction
i. Statement of intent to
construct;
ii. Anticipated date of commencement of onstruction;
§ 60.2952.
§ 60.2952.
iii. Documentation for siting
requirements;
§ 60.2952.
iv. Waste management plan;
and
§ 60.2952.
v. Anticipated date of initial
startup.
§ 60.2952.
2. Startup
notification
a. Prior to initial
startup
i. Types of waste to be
burned;
ii. Maximum design waste burning capacity;
§ 60.2953.
§ 60.2953.
iii. Anticipated maximum
charge rate;
§ 60.2953.
iv. If applicable, the
petition for site-specific operating limits; and
§ 60.2953.
v. Anticipated date of initial
startup.
§ 60.2953.
3. Initial test
report
a. No later than 60 days
following the initial performance test
i. Complete test report for
the initial performance test; and
ii. The values for the site-specific operating limits
§ 60.2954.
§ 60.2954.
4. Annual
report
a. No later than 12 months
following the submission of the initial test report. Subsequent
reports are to be submitted no more than 12 months following the
previous report
i. Company Name and
address;
ii. Statement and signature by the owner or operator;
iii. Date of report;
iv. Values for the operating limits;
v. If no deviations or malfunctions were reported, a statement that
no deviations occurred during the reporting period;
§§ 60.2955 and 60.2956.
§§ 60.2955 and 60.2956.
§§ 60.2955 and 60.2956.
§§ 60.2955 and 60.2956.
§§ 60.2955 and 60.2956.
vi. Highest and lowest
recorded 12-hour averages, as applicable, for carbon monoxide
emissions and highest and lowest recorded 3-hour averages, as
applicable, for each operating parameter recorded for the calendar
year being reported;
§§ 60.2955 and 60.2956.
vii. Information for
deviations or malfunctions recorded under § 60.2949(b)(6) and (c)
through (e);
§§ 60.2955 and 60.2956.
viii. If a performance test
was conducted during the reporting period, the results of the
test;
§§ 60.2955 and 60.2956.
ix. If a performance test was
not conducted during the reporting period, a statement that the
requirements of § 60.2934 (a) or (b) were met; and
§§ 60.2955 and 60.2956.
x. Documentation of periods
when all qualified OSWI unit operators were unavailable for more
than 12 hours but less than 2 weeks.
§§ 60.2955 and 60.2956.
5. Emission
limitation or operating limit deviation report
a. By August 1 of that year
for data collected during the first half of the calendar year. By
February 1 of the following year for data collected during the
second half of the calendar year
i. Dates and times of
deviation;
ii. Averaged and recorded data for those dates;
iii. Duration and causes of each deviation and the corrective
actions taken;
iv. Copy of operating limit monitoring data and any test
reports;
v. Dates, times, and causes for monitor downtimes incidents;
vi. Whether each deviation occurred during a period of startup,
shutdown, or malfunction; and
§§ 60.2957 and 60.2958.
§§ 60.2957 and 60.2958.
§§ 60.2957 and 60.2958.
§§ 60.2957 and 60.2958.
§§ 60.2957 and 60.2958.
§§ 60.2957 and 60.2958.
vii. Dates, times, and
durations of any bypass of the control device.
§§ 60.2957 and 60.2958.
6. Qualified
operator deviation notification
a. Within 10 days of
deviation
i. Statement of cause of
deviation;
ii. Description of efforts to have an accessible qualified
operator; and
§ 60.2959(a)(1).
§ 60.2959(a)(1)
iii. The date a qualified
operator will be accessible
§ 60.2959(a)(1).
7. Qualified
operation deviation status report
a. Every 4 weeks following
deviation
i. Description of efforts to
have an accessible qualified operator;
ii. The date a qualified operator will be accessible; and
§ 60.2959(a)(2).
§ 60.2959(a)(2).
iii. Request to continue
operation
§ 60.2959(a)(2).
8. Qualified
operator deviation notification of resumed operation
a. Prior to resuming
operation
i. Notification that you are
resuming operation
§ 60.2959(b).
Note: This table is only a summary, see the
referenced sections of the rule for the complete requirements.
[70 FR 74892, Dec. 16, 2005, as amended at 71 FR 67806, Nov. 24,
2006]
Table 1 to Subpart FFFF of Part 60 - Model Rule - Compliance Schedule
40:8.0.1.1.1.33.257.76.38 :
Table 1 to Subpart FFFF of Part 60 - Model Rule - Compliance
Schedule
As stated in § 60.3000, you must comply with the following:
Complete this action
By this date
a
Final compliance
b
(Dates to be specified in
State plan) c.
a Site-specific schedules can be
used at the discretion of the State.
b Final compliance means that you
complete all process changes and retrofit of control devices so
that, when the incineration unit is brought on line, all process
changes and air pollution control devices necessary to meet the
emission limitations operate as designed.
c The date can be no later than 3
years after the effective date of State plan approval or December
16, 2010, whichever is earlier.
Table 2 to Subpart FFFF of Part 60 - Model Rule - Emission Limitations
40:8.0.1.1.1.33.257.76.39 :
Table 2 to Subpart FFFF of Part 60 - Model Rule - Emission
Limitations
As stated in § 60.3022, you must comply with the following:
For the air pollutant
You must meet this emission
limitation a
Using this averaging
time
And determining compliance
using this
method
1. Cadmium
18 micrograms per dry standard
cubic meter
3-run average (1 hour minimum
sample time per run)
Method 29 of appendix A of
this part.
2. Carbon
monoxide
40 parts per million by dry
volume
3-run average (1 hour minimum
sample time per run during performance test), and 12-hour rolling
averages measured using CEMS b
Method 10, 10A, or 10B of
appendix A of this part and CEMS.
3. Dioxins/furans
(total basis)
33 nanograms per dry standard
cubic meter
3-run average (1 hour minimum
sample time per run)
Method 23 of appendix A of
this part.
4. Hydrogen
chloride
15 parts per million by dry
volume
3-run average (1 hour minimum
sample time per run)
Method 26A of appendix A of
this part.
5. Lead
226 micrograms per dry
standard cubic meter
3-run average (1 hour minimum
sample time per run)
Method 29 of appendix A of
this part.
6. Mercury
74 micrograms per dry standard
cubic meter
3-run average (1 hour minimum
sample time per run)
Method 29 of appendix A of
this part.
7. Opacity
10 percent
6-minute average (observe over
three 1-hour test runs; i.e., thirty 6-minute averages)
Method 9 of appendix A of this
part.
8. Oxides of
nitrogen
103 parts per million by dry
volume
3-run average (1 hour minimum
sample time per run)
Method 7, 7A, 7C, 7D, or 7E of
appendix A of this part, or ANSI/ASME PTC 19.10-1981 (IBR, see §
60.17(h)) in lieu of Methods 7 and 7C only.
9. Particulate
matter
0.013 grains per dry standard
cubic foot
3-run average (1 hour minimum
sample time per run)
Method 5 or 29 of appendix A
of this part.
10. Sulfur
dioxide
3.1 parts per million by dry
volume
3-run average (1 hour minimum
sample time per run)
Method 6 or 6C of appendix A
of this part, or ANSI/ASME PTC 19.10-1981 (IBR, see § 60.17(h)) in
lieu of Method 6 only.
a All emission limitations
(except for opacity) are measured at 7 percent oxygen, dry basis at
standard conditions.
b Calculated each hour as the
average of the previous 12 operating hours.
Table 3 to Subpart FFFF of Part 60 - Model Rule - Operating Limits for Incinerators and Wet Scrubbers
40:8.0.1.1.1.33.257.76.40 :
Table 3 to Subpart FFFF of Part 60 - Model Rule - Operating Limits
for Incinerators and Wet Scrubbers
As stated in § 60.3023, you must comply with the following:
For these
operating parameters
You must
establish operating limits
And monitoring
using these minimum frequencies
Data measurement
Data recording
Averaging time
1. Charge
rate
Maximum charge rate
Continuous
Every hour
Daily for batch units. 3-hour
rolling for continuous and intermittent units. a
2. Pressure drop
across the wet scrubber or amperage to wet scrubber
Minimum pressure drop or
amperage
Continuous
Every 15 minutes
3-hour rolling.
a
3. Scrubber liquor
flow rate
Minimum flow rate
Continuous
Every 15 minutes
3-hour rolling.
a
4. Scrubber liquor
pH
Minimum pH
Continuous
Every 15 minutes
3-hour rolling.
a
a Calculated each hour as the
average of the previous 3 operating hours.
Table 4 to Subpart FFFF of Part 60 - Model Rule - Requirements for Continuous Emission Monitoring Systems (CEMS)
40:8.0.1.1.1.33.257.76.41 :
Table 4 to Subpart FFFF of Part 60 - Model Rule - Requirements for
Continuous Emission Monitoring Systems (CEMS)
As stated in § 60.3039, you must comply with the following:
For the following
pollutants
Use the following span values
for your CEMS
Use the following performance
specifications (P.S.) in appendix B of this part for your CEMS
If needed to meet minimum
data requirements, use the following alternate methods in appendix
A of this part to collect data
1. Carbon
Monoxide
125 percent of the maximum
hourly potential carbon monoxide emissions of the waste combustion
unit
P.S.4A
Method 10.
2. Oxygen
25 percent oxygen
P.S.3
Method 3A or 3B, or ANSI/ASME
PTC 19.10-1981 (IBR, see § 60.17(h)) in lieu of Method 3B
only.
Table 5 to Subpart FFFF of Part 60 - Model Rule - Summary of Reporting Requirements
40:8.0.1.1.1.33.257.76.42 :
Table 5 to Subpart FFFF of Part 60 - Model Rule - Summary of
Reporting Requirements
As stated in § 60.3048, you must comply with the following:
Report
Due date
Contents
Reference
1. Initial test
report
a. No later than 60 days
following the initial performance test
i. Complete test report for
the initial performance test; and
§ 60.3049.
ii. The values for the
site-specific operating limits
§ 60.3049.
2. Waste
management plan
a. No later than 60 days
following the initial performance test
i. Reduction or separation of
recyclable materials; and
§§ 60.3010 through
60.3012.
ii. Identification of
additional waste management measures and how they will be
implemented
§§ 60.3010 through
60.3012.
3. Annual
Report
a. No later than 12 months
following the submission of the initial test report. Subsequent
reports are to be submitted no more than 12 months following the
previous report
i. Company Name and
address;
§§ 60.3050 and 60.3051.
ii. Statement and signature by
the owner or operator;
§§ 60.3050 and 60.3051.
iii. Date of report;
§§ 60.3050 and 60.3051.
iv. Values for the operation
limits;
§§ 60.3050 and 60.3051.
v. If no deviations or
malfunctions were reported, a statement that no deviations occurred
during the reporting period;
§§ 60.3050 and 60.3051.
vi. Highest and lowest
recorded 12-hour averages, as applicable, for carbon monoxide
emissions and highest and lowest recorded 3-hour averages, as
applicable, for each operating parameter recorded for the calendar
year being reported;
§§ 60.3050 and 60.3051.
vii. Information for
deviations or malfunctions recorded under § 60.2949(b)(6) and (c)
through (e);
§§ 60.3050 and 60.3051.
viii. If a performance test
was conducted during the reporting period, the results of the
test;
§§ 60.3050 and 60.3051.
ix. If a performance test was
not conducted during the reporting period, a statement that the
requirements of § 60.2934(a) or (b) were met; and
§§ 60.3050 and 60.3051.
x. Documentation of periods
when all qualified OSWI unit operators were unavailable for more
than 12 hours but less than 2 weeks
§§ 60.3050 and 60.3051.
4. Emission
limitation or operating limit deviation report
a. By August 1 of that year
for data collected during the first half of the calendar year. By
February 1 of the following year for data collected during the
second half of the calendar year
i. Dates and times of
deviation;
§§ 60.3052 and 60.3053.
ii. Averaged and recorded data
for those dates;
§§ 60.3052 and 60.3053.
iii. Duration and causes of
each deviation and the corrective actions taken.
§§ 60.3052 and 60.3053.
iv. Copy of operating limit
monitoring data and any test reports;
§§ 60.3052 and 60.3053.
v. Dates, times, and causes
for monitor downtime incidents;
§§ 60.3052 and 60.3053.
vi. Whether each deviation
occurred during a period of startup, shutdown, or malfunction;
and
§§ 60.3052 and 60.3053.
vii. Dates, times, and
duration of any bypass of the control device
§§ 60.3052 and 60.3053.
5. Qualified
operator deviation notification
a. Within 10 days of
deviation
i. Statement of cause of
deviation;
§ 60.3054(a)(1).
ii. Description of efforts to
have an accessible qualified operator; and
§ 60.3054(a)(1).
iii. The date a qualified
operator will be accessible
§ 60.3054(a)(1).
6. Qualified
operation deviation status report
a. Every 4 weeks following
deviation
i. Description of efforts to
have an accessible qualified operator;
§ 60.3054(a)(2).
ii. The date a qualified
operator will be accessible; and
§ 60.3054(a)(2).
iii. Request to continue
operation
§ 60.3054(a)(2).
7. Qualified
operator deviation notification of resumed operation
a. Prior to resuming
operation
i. Notification that you are
resuming operation
§ 60.3054(b).
Note: This table is only a summary, see the
referenced sections of the rule for the complete requirements.
[70 FR 74907, Dec. 16, 2005, as amended at 71 FR 67806, Nov. 24,
2006]
Table 1 to Subpart IIII of Part 60 - Emission Standards for Stationary Pre-2007 Model Year Engines With a Displacement of <10 Liters per Cylinder and 2007-2010 Model Year Engines >2,237 KW (3,000 HP) and With a Displacement of <10 Liters per Cylinder
40:8.0.1.1.1.35.268.21.43 :
Table 1 to Subpart IIII of Part 60 - Emission Standards for
Stationary Pre-2007 Model Year Engines With a Displacement of
<10 Liters per Cylinder and 2007-2010 Model Year Engines
>2,237 KW (3,000 HP) and With a Displacement of <10 Liters
per Cylinder
[As stated in §§ 60.4201(b),
60.4202(b), 60.4204(a), and 60.4205(a), you must comply with the
following emission standards]
Maximum engine
power
Emission
standards for stationary pre-2007 model year engines with a
displacement of <10 liters per cylinder and 2007-2010 model year
engines >2,237 KW (3,000 HP) and with a displacement of <10
liters per cylinder in g/KW-hr (g/HP-hr)
NMHC + NOX
HC
NOX
CO
PM
KW<8
(HP<11)
10.5 (7.8)
8.0 (6.0)
1.0 (0.75)
8≤KW<19
(11≤HP<25)
9.5 (7.1)
6.6 (4.9)
0.80 (0.60)
19≤KW<37
(25≤HP<50)
9.5 (7.1)
5.5 (4.1)
0.80 (0.60)
37≤KW<56
(50≤HP<75)
9.2 (6.9)
56≤KW<75
(75≤HP<100)
9.2 (6.9)
75≤KW<130
(100≤HP<175)
9.2 (6.9)
130≤KW<225
(175≤HP<300)
1.3 (1.0)
9.2 (6.9)
11.4 (8.5)
0.54 (0.40)
225≤KW<450
(300≤HP<600)
1.3 (1.0)
9.2 (6.9)
11.4 (8.5)
0.54 (0.40)
450≤KW≤560
(600≤HP≤750)
1.3 (1.0)
9.2 (6.9)
11.4 (8.5)
0.54 (0.40)
KW>560
(HP>750)
1.3 (1.0)
9.2 (6.9)
11.4 (8.5)
0.54 (0.40)
Table 2 to Subpart IIII of Part 60 - Emission Standards for 2008 Model Year and Later Emergency Stationary CI ICE <37 KW (50 HP) With a Displacement of <10 Liters per Cylinder
40:8.0.1.1.1.35.268.21.44 :
Table 2 to Subpart IIII of Part 60 - Emission Standards for 2008
Model Year and Later Emergency Stationary CI ICE <37 KW (50 HP)
With a Displacement of <10 Liters per Cylinder
[As stated in § 60.4202(a)(1), you
must comply with the following emission standards]
Engine power
Emission
standards for 2008 model year and later emergency stationary CI ICE
<37 KW (50 HP) with a displacement of <10 liters per cylinder
in g/KW-hr (g/HP-hr)
Model year(s)
NOX + NMHC
CO
PM
KW<8
(HP<11)
2008 +
7.5 (5.6)
8.0 (6.0)
0.40 (0.30)
8≤KW<19
(11≤HP<25)
2008 +
7.5 (5.6)
6.6 (4.9)
0.40 (0.30)
19≤KW<37
(25≤HP<50)
2008 +
7.5 (5.6)
5.5 (4.1)
0.30 (0.22)
Table 3 to Subpart IIII of Part 60 - Certification Requirements for Stationary Fire Pump Engines
40:8.0.1.1.1.35.268.21.45 :
Table 3 to Subpart IIII of Part 60 - Certification Requirements for
Stationary Fire Pump Engines
As stated in § 60.4202(d), you must
certify new stationary fire pump engines beginning with the
following model years:
Engine
power
Starting model year engine
manufacturers must certify
new
stationary
fire pump
engines
according to
§ 60.4202(d) 1
KW<75
(HP<100)
2011
75≤KW<130
(100≤HP<175)
2010
130≤KW≤560
(175≤HP≤750)
2009
KW>560
(HP>750)
2008
1Manufacturers of fire pump
stationary CI ICE with a maximum engine power greater than or equal
to 37 kW (50 HP) and less than 450 KW (600 HP) and a rated speed of
greater than 2,650 revolutions per minute (rpm) are not required to
certify such engines until three model years following the model
year indicated in this Table 3 for engines in the applicable engine
power category.
[71 FR 39172, July 11, 2006, as amended at 76 FR 37972, June 28,
2011]
Table 4 to Subpart IIII of Part 60 - Emission Standards for Stationary Fire Pump Engines
40:8.0.1.1.1.35.268.21.46 :
Table 4 to Subpart IIII of Part 60 - Emission Standards for
Stationary Fire Pump Engines
[As stated in §§ 60.4202(d) and
60.4205(c), you must comply with the following emission standards
for stationary fire pump engines]
Maximum engine power
Model year(s)
NMHC + NOX
CO
PM
KW<8
(HP<11)
2010 and earlier
10.5 (7.8)
8.0 (6.0)
1.0 (0.75)
2011 +
7.5 (5.6)
0.40 (0.30)
8≤KW<19
(11≤HP<25)
2010 and earlier
9.5 (7.1)
6.6 (4.9)
0.80 (0.60)
2011 +
7.5 (5.6)
0.40 (0.30)
19≤KW<37
(25≤HP<50)
2010 and earlier
9.5 (7.1)
5.5 (4.1)
0.80 (0.60)
2011 +
7.5 (5.6)
0.30 (0.22)
37≤KW<56
(50≤HP<75)
2010 and earlier
10.5 (7.8)
5.0 (3.7)
0.80 (0.60)
2011 + 1
4.7 (3.5)
0.40 (0.30)
56≤KW<75
(75≤HP<100)
2010 and earlier
10.5 (7.8)
5.0 (3.7)
0.80 (0.60)
2011 + 1
4.7 (3.5)
0.40 (0.30)
75≤KW<130
(100≤HP<175)
2009 and earlier
10.5 (7.8)
5.0 (3.7)
0.80 (0.60)
2010 + 2
4.0 (3.0)
0.30 (0.22)
130≤KW<225
(175≤HP<300)
2008 and earlier
10.5 (7.8)
3.5 (2.6)
0.54 (0.40)
2009 + 3
4.0 (3.0)
0.20 (0.15)
225≤KW<450
(300≤HP<600)
2008 and earlier
10.5 (7.8)
3.5 (2.6)
0.54 (0.40)
2009 + 3
4.0 (3.0)
0.20 (0.15)
450≤KW≤560
(600≤HP≤750)
2008 and earlier
10.5 (7.8)
3.5 (2.6)
0.54 (0.40)
2009 +
4.0 (3.0)
0.20 (0.15)
KW>560
(HP>750)
2007 and earlier
10.5 (7.8)
3.5 (2.6)
0.54 (0.40)
2008 +
6.4 (4.8)
0.20 (0.15)
1 For model years 2011-2013,
manufacturers, owners and operators of fire pump stationary CI ICE
in this engine power category with a rated speed of greater than
2,650 revolutions per minute (rpm) may comply with the emission
limitations for 2010 model year engines.
2 For model years 2010-2012,
manufacturers, owners and operators of fire pump stationary CI ICE
in this engine power category with a rated speed of greater than
2,650 rpm may comply with the emission limitations for 2009 model
year engines.
3 In model years 2009-2011,
manufacturers of fire pump stationary CI ICE in this engine power
category with a rated speed of greater than 2,650 rpm may comply
with the emission limitations for 2008 model year engines.
Table 5 to Subpart IIII of Part 60 - Labeling and Recordkeeping Requirements for New Stationary Emergency Engines
40:8.0.1.1.1.35.268.21.47 :
Table 5 to Subpart IIII of Part 60 - Labeling and Recordkeeping
Requirements for New Stationary Emergency Engines
[You must comply with the labeling
requirements in § 60.4210(f) and the recordkeeping requirements in
§ 60.4214(b) for new emergency stationary CI ICE beginning in the
following model years:]
Engine power
Starting model year
19≤KW<56
(25≤HP<75)
2013
56≤KW<130
(75≤HP<175)
2012
KW≥130
(HP≥175)
2011
Table 6 to Subpart IIII of Part 60 - Optional 3-Mode Test Cycle for Stationary Fire Pump Engines
40:8.0.1.1.1.35.268.21.48 :
Table 6 to Subpart IIII of Part 60 - Optional 3-Mode Test Cycle for
Stationary Fire Pump Engines
[As stated in § 60.4210(g),
manufacturers of fire pump engines may use the following test cycle
for testing fire pump engines:]
Mode No.
Engine speed
1
Torque
(percent) 2
Weighting
factors
1
Rated
100
0.30
2
Rated
75
0.50
3
Rated
50
0.20
1 Engine speed: ±2 percent of
point.
2 Torque: NFPA certified
nameplate HP for 100 percent point. All points should be ±2 percent
of engine percent load value.
Table 7 to Subpart IIII of Part 60 - Requirements for Performance Tests for Stationary CI ICE With a Displacement of ≥30 Liters per Cylinder
40:8.0.1.1.1.35.268.21.49 :
Table 7 to Subpart IIII of Part 60 - Requirements for Performance
Tests for Stationary CI ICE With a Displacement of ≥30 Liters per
Cylinder
As stated in § 60.4213, you must comply with the following
requirements for performance tests for stationary CI ICE with a
displacement of ≥30 liters per cylinder:
Each
Complying with the
requirement to
You must
Using
According to the following
requirements
1. Stationary CI
internal combustion engine with a displacement of ≥ 30 liters per
cylinder
a. Reduce NOX emissions by 90
percent or more;
i. Select the sampling port
location and number/location of traverse points at the inlet and
outlet of the control device;
(a) For NOX, O2, and moisture
measurement, ducts ≤6 inches in diameter may be sampled at a single
point located at the duct centroid and ducts >6 and ≤12 inches
in diameter may be sampled at 3 traverse points located at 16.7,
50.0, and 83.3% of the measurement line ('3-point long line'). If
the duct is >12 inches in diameter and the sampling port
location meets the two and half-diameter criterion of Section
11.1.1 of Method 1 of 40 CFR part 60, appendix A-1, the duct may be
sampled at '3-point long line'; otherwise, conduct the
stratification testing and select sampling points according to
Section 8.1.2 of Method 7E of 40 CFR part 60, appendix A-4.
ii. Measure O2 at the inlet
and outlet of the control device;
(1) Method 3, 3A, or 3B of 40
CFR part 60, appendix A-2
(b) Measurements to determine
O2 concentration must be made at the same time as the measurements
for NOX concentration.
iii. If necessary, measure
moisture content at the inlet and outlet of the control device;
and
(2) Method 4 of 40 CFR part
60, appendix A-3, Method 320 of 40 CFR part 63, appendix A, or ASTM
D 6348-03 (incorporated by reference, see § 60.17)
(c) Measurements to determine
moisture content must be made at the same time as the measurements
for NOX concentration.
iv. Measure NOX at the inlet
and outlet of the control device.
(3) Method 7E of 40 CFR part
60, appendix A-4, Method 320 of 40 CFR part 63, appendix A, or ASTM
D 6348-03 (incorporated by reference, see § 60.17)
(d) NOX concentration must be
at 15 percent O2, dry basis. Results of this test consist of the
average of the three 1-hour or longer runs.
b. Limit the concentration of
NOX in the stationary CI internal combustion engine exhaust.
i. Select the sampling port
location and number/location of traverse points at the exhaust of
the stationary internal combustion engine;
(a) For NOX, O2, and moisture
measurement, ducts ≤6 inches in diameter may be sampled at a single
point located at the duct centroid and ducts >6 and ≤12 inches
in diameter may be sampled at 3 traverse points located at 16.7,
50.0, and 83.3% of the measurement line ('3-point long line'). If
the duct is >12 inches in diameter and the sampling port
location meets the two and half-diameter criterion of Section
11.1.1 of Method 1 of 40 CFR part 60, appendix A-1, the duct may be
sampled at '3-point long line'; otherwise, conduct the
stratification testing and select sampling points according to
Section 8.1.2 of Method 7E of 40 CFR part 60, appendix A-4.
ii. Determine the O2
concentration of the stationary internal combustion engine exhaust
at the sampling port location;
(1) Method 3, 3A, or 3B of 40
CFR part 60, appendix A-2
(b) Measurements to determine
O2 concentration must be made at the same time as the measurement
for NOX concentration.
iii. If necessary, measure
moisture content of the stationary internal combustion engine
exhaust at the sampling port location; and
(2) Method 4 of 40 CFR part
60, appendix A-3, Method 320 of 40 CFR part 63, appendix A, or ASTM
D 6348-03 (incorporated by reference, see § 60.17)
(c) Measurements to determine
moisture content must be made at the same time as the measurement
for NOX concentration.
iv. Measure NOX at the exhaust
of the stationary internal combustion engine; if using a control
device, the sampling site must be located at the outlet of the
control device.
(3) Method 7E of 40 CFR part
60, appendix A-4, Method 320 of 40 CFR part 63, appendix A, or ASTM
D 6348-03 (incorporated by reference, see § 60.17)
(d) NOX concentration must be
at 15 percent O2, dry basis. Results of this test consist of the
average of the three 1-hour or longer runs.
c. Reduce PM emissions by 60
percent or more
i. Select the sampling port
location and the number of traverse points;
(1) Method 1 or 1A of 40 CFR
part 60, appendix A-1
(a) Sampling sites must be
located at the inlet and outlet of the control device.
ii. Measure O2 at the inlet
and outlet of the control device;
(2) Method 3, 3A, or 3B of 40
CFR part 60, appendix A-2
(b) Measurements to determine
O2 concentration must be made at the same time as the measurements
for PM concentration.
iii. If necessary, measure
moisture content at the inlet and outlet of the control device;
and
(3) Method 4 of 40 CFR part
60, appendix A-3
(c) Measurements to determine
and moisture content must be made at the same time as the
measurements for PM concentration.
iv. Measure PM at the inlet
and outlet of the control device.
(4) Method 5 of 40 CFR part
60, appendix A-3
(d) PM concentration must be
at 15 percent O2, dry basis. Results of this test consist of the
average of the three 1-hour or longer runs.
d. Limit the concentration of
PM in the stationary CI internal combustion engine exhaust
i. Select the sampling port
location and the number of traverse points;
(1) Method 1 or 1A of 40 CFR
part 60, appendix A-1
(a) If using a control device,
the sampling site must be located at the outlet of the control
device.
ii. Determine the O2
concentration of the stationary internal combustion engine exhaust
at the sampling port location;
(2) Method 3, 3A, or 3B of 40
CFR part 60, appendix A-2
(b) Measurements to determine
O2 concentration must be made at the same time as the measurements
for PM concentration.
iii. If necessary, measure
moisture content of the stationary internal combustion engine
exhaust at the sampling port location; and
(3) Method 4 of 40 CFR part
60, appendix A-3
(c) Measurements to determine
moisture content must be made at the same time as the measurements
for PM concentration.
iv. Measure PM at the exhaust
of the stationary internal combustion engine.
(4) Method 5 of 40 CFR part
60, appendix A-3
(d) PM concentration must be
at 15 percent O2, dry basis. Results of this test consist of the
average of the three 1-hour or longer runs.
[79 FR 11251, Feb. 27, 2014]
Table 8 to Subpart IIII of Part 60 - Applicability of General Provisions to Subpart IIII
40:8.0.1.1.1.35.268.21.50 :
Table 8 to Subpart IIII of Part 60 - Applicability of General
Provisions to Subpart IIII
[As stated in § 60.4218, you must
comply with the following applicable General Provisions:]
General Provisions
citation
Subject of citation
Applies
to
subpart
Explanation
§ 60.1
General applicability of the
General Provisions
Yes
§ 60.2
Definitions
Yes
Additional terms defined in §
60.4219.
§ 60.3
Units and abbreviations
Yes
§ 60.4
Address
Yes
§ 60.5
Determination of construction
or modification
Yes
§ 60.6
Review of plans
Yes
§ 60.7
Notification and
Recordkeeping
Yes
Except that § 60.7 only
applies as specified in § 60.4214(a).
§ 60.8
Performance tests
Yes
Except that § 60.8 only
applies to stationary CI ICE with a displacement of (≥30 liters per
cylinder and engines that are not certified.
§ 60.9
Availability of
information
Yes
§ 60.10
State Authority
Yes
§ 60.11
Compliance with standards and
maintenance requirements
No
Requirements are specified in
subpart IIII.
§ 60.12
Circumvention
Yes
§ 60.13
Monitoring requirements
Yes
Except that § 60.13 only
applies to stationary CI ICE with a displacement of (≥30 liters per
cylinder.
§ 60.14
Modification
Yes
§ 60.15
Reconstruction
Yes
§ 60.16
Priority list
Yes
§ 60.17
Incorporations by
reference
Yes
§ 60.18
General control device
requirements
No
§ 60.19
General notification and
reporting requirements
Yes
Table 1 to Subpart JJJJ of Part 60 - NOX, CO, and VOC Emission Standards for Stationary Non-Emergency SI Engines ≥100 HP (Except Gasoline and Rich Burn LPG), Stationary SI Landfill/Digester Gas Engines, and Stationary Emergency Engines >25 HP
40:8.0.1.1.1.36.279.20.51 :
Table 1 to Subpart JJJJ of Part 60 - NOX, CO, and VOC Emission
Standards for Stationary Non-Emergency SI Engines ≥100 HP (Except
Gasoline and Rich Burn LPG), Stationary SI Landfill/Digester Gas
Engines, and Stationary Emergency Engines >25 HP
Engine type
and fuel
Maximum
engine power
Manufacture
date
Emission
standards a
g/HP-hr
ppmvd at 15%
O2
NOX
CO
VOC d
NOX
CO
VOC d
Non-Emergency SI
Natural Gas b and Non-Emergency SI Lean Burn LPG b
100≤HP<500
7/1/2008
2.0
4.0
1.0
160
540
86
1/1/2011
1.0
2.0
0.7
82
270
60
Non-Emergency SI
Lean Burn Natural Gas and LPG
500≤HP<1,350
1/1/2008
2.0
4.0
1.0
160
540
86
7/1/2010
1.0
2.0
0.7
82
270
60
Non-Emergency SI
Natural Gas and Non-Emergency SI Lean Burn LPG (except lean burn
500≤HP<1,350)
HP≥500
7/1/2007
2.0
4.0
1.0
160
540
86
HP≥500
7/1/2010
1.0
2.0
0.7
82
270
60
Landfill/Digester
Gas (except lean burn 500≤HP<1,350)
HP<500
7/1/2008
3.0
5.0
1.0
220
610
80
1/1/2011
2.0
5.0
1.0
150
610
80
HP≥500
7/1/2007
3.0
5.0
1.0
220
610
80
7/1/2010
2.0
5.0
1.0
150
610
80
Landfill/Digester
Gas Lean Burn
500≤HP<1,350
1/1/2008
3.0
5.0
1.0
220
610
80
7/1/2010
2.0
5.0
1.0
150
610
80
Emergency
25<HP<130
1/1/2009
c 10
387
N/A
N/A
N/A
N/A
HP≥130
2.0
4.0
1.0
160
540
86
a Owners and operators of
stationary non-certified SI engines may choose to comply with the
emission standards in units of either g/HP-hr or ppmvd at 15
percent O2.
b Owners and operators of new or
reconstructed non-emergency lean burn SI stationary engines with a
site rating of greater than or equal to 250 brake HP located at a
major source that are meeting the requirements of 40 CFR part 63,
subpart ZZZZ, Table 2a do not have to comply with the CO emission
standards of Table 1 of this subpart.
c The emission standards
applicable to emergency engines between 25 HP and 130 HP are in
terms of NOX + HC.
d For purposes of this subpart,
when calculating emissions of volatile organic compounds, emissions
of formaldehyde should not be included.
[76 FR 37975, June 28, 2011]
Table 2 to Subpart JJJJ of Part 60 - Requirements for Performance Tests
40:8.0.1.1.1.36.279.20.52 :
Table 2 to Subpart JJJJ of Part 60 - Requirements for Performance
Tests
As stated in § 60.4244, you must comply with the following
requirements for performance tests within 10 percent of 100 percent
peak (or the highest achievable) load].
For each
Complying with the
requirement to
You must
Using
According to the
following
requirements
1. Stationary SI
internal combustion engine demonstrating compliance according to §
60.4244
a. Limit the concentration of
NOX in the stationary SI internal combustion engine exhaust
i. Select the sampling port
location and the number/location of traverse points at the exhaust
of the stationary internal combustion engine;
(1) Method 1 or 1A of 40 CFR
part 60, appendix A-1, if measuring flow rate
(a) Alternatively, for NOX,
O2, and moisture measurement, ducts ≤6 inches in diameter may be
sampled at a single point located at the duct centroid and ducts
>6 and ≤12 inches in diameter may be sampled at 3 traverse
points located at 16.7, 50.0, and 83.3% of the measurement line
(`3-point long line'). If the duct is >12 inches in diameter and
the sampling port location meets the two and half-diameter
criterion of Section 11.1.1 of Method 1 of 40 CFR part 60, Appendix
A, the duct may be sampled at `3-point long line'; otherwise,
conduct the stratification testing and select sampling points
according to Section 8.1.2 of Method 7E of 40 CFR part 60, Appendix
A.
ii. Determine the O2
concentration of the stationary internal combustion engine exhaust
at the sampling port location;
(2) Method 3, 3A, or 3B
b of 40 CFR part 60, appendix A-2 or ASTM Method
D6522-00 (Reapproved 2005) a d
(b) Measurements to determine
O2 concentration must be made at the same time as the measurements
for NOX concentration.
iii. If necessary, determine
the exhaust flowrate of the stationary internal combustion engine
exhaust;
(3) Method 2 or 2C of 40 CFR
part 60, appendix A-1 or Method 19 of 40 CFR part 60, appendix
A-7
(c) Measurements to determine
the exhaust flowrate must be made (1) at the same time as the
measurement for NOX concentration or, alternatively (2) according
to the option in Section 11.1.2 of Method 1A of 40 CFR part 60,
Appendix A-1, if applicable.
iv. If necessary, measure
moisture content of the stationary internal combustion engine
exhaust at the sampling port location; and
(4) Method 4 of 40 CFR part
60, appendix A-3, Method 320 of 40 CFR part 63, appendix A,
e or ASTM Method D6348-03 d e
(d) Measurements to determine
moisture must be made at the same time as the measurement for NOX
concentration.
v. Measure NOX at the exhaust
of the stationary internal combustion engine; if using a control
device, the sampling site must be located at the outlet of the
control device
(5) Method 7E of 40 CFR part
60, appendix A-4, ASTM Method D6522-00 (Reapproved 2005),a d Method
320 of 40 CFR part 63, appendix A, e or ASTM Method
D6348-03 d e
(e) Results of this test
consist of the average of the three 1-hour or longer runs.
b. Limit the concentration of
CO in the stationary SI internal combustion engine exhaust
i. Select the sampling port
location and the number/location of traverse points at the exhaust
of the stationary internal combustion engine;
(1) Method 1 or 1A of 40 CFR
part 60, appendix A-1, if measuring flow rate
(a) Alternatively, for CO, O2,
and moisture measurement, ducts ≤6 inches in diameter may be
sampled at a single point located at the duct centroid and ducts
>6 and ≤12 inches in diameter may be sampled at 3 traverse
points located at 16.7, 50.0, and 83.3% of the measurement line
(`3-point long line'). If the duct is >12 inches in diameter and
the sampling port location meets the two and half-diameter
criterion of Section 11.1.1 of Method 1 of 40 CFR part 60, Appendix
A, the duct may be sampled at `3-point long line'; otherwise,
conduct the stratification testing and select sampling points
according to Section 8.1.2 of Method 7E of 40 CFR part 60, Appendix
A.
ii. Determine the O2
concentration of the stationary internal combustion engine exhaust
at the sampling port location;
(2) Method 3, 3A, or 3B
b of 40 CFR part 60, appendix A-2 or ASTM Method
D6522-00 (Reapproved 2005) a d
(b) Measurements to determine
O2 concentration must be made at the same time as the measurements
for CO concentration.
iii. If necessary, determine
the exhaust flowrate of the stationary internal combustion engine
exhaust;
(3) Method 2 or 2C of 40 CFR
60, appendix A-1 or Method 19 of 40 CFR part 60, appendix A-7
(c) Measurements to determine
the exhaust flowrate must be made (1) at the same time as the
measurement for CO concentration or, alternatively (2) according to
the option in Section 11.1.2 of Method 1A of 40 CFR part 60,
Appendix A-1, if applicable.
iv. If necessary, measure
moisture content of the stationary internal combustion engine
exhaust at the sampling port location; and
(4) Method 4 of 40 CFR part
60, appendix A-3, Method 320 of 40 CFR part 63, appendix A,
e or ASTM Method D6348-03 d e
(d) Measurements to determine
moisture must be made at the same time as the measurement for CO
concentration.
v. Measure CO at the exhaust
of the stationary internal combustion engine; if using a control
device, the sampling site must be located at the outlet of the
control device
(5) Method 10 of 40 CFR part
60, appendix A4, ASTM Method D6522-00 (Reapproved 2005),a d e
Method 320 of 40 CFR part 63, appendix A, e or ASTM
Method D6348-03 d e
(e) Results of this test
consist of the average of the three 1-hour or longer runs.
c. Limit the concentration of
VOC in the stationary SI internal combustion engine exhaust
i. Select the sampling port
location and the number/location of traverse points at the exhaust
of the stationary internal combustion engine;
(1) Method 1 or 1A of 40 CFR
part 60, appendix A-1, if measuring flow rate
(a) Alternatively, for VOC,
O2, and moisture measurement, ducts ≤6 inches in diameter may be
sampled at a single point located at the duct centroid and ducts
>6 and ≤12 inches in diameter may be sampled at 3 traverse
points located at 16.7, 50.0, and 83.3% of the measurement line
(`3-point long line'). If the duct is >12 inches in diameter and
the sampling port location meets the two and half-diameter
criterion of Section 11.1.1 of Method 1 of 40 CFR part 60, Appendix
A, the duct may be sampled at `3-point long line'; otherwise,
conduct the stratification testing and select sampling points
according to Section 8.1.2 of Method 7E of 40 CFR part 60, Appendix
A.
ii. Determine the O2
concentration of the stationary internal combustion engine exhaust
at the sampling port location;
(2) Method 3, 3A, or 3B
b of 40 CFR part 60, appendix A-2 or ASTM Method
D6522-00 (Reapproved 2005) a d
(b) Measurements to determine
O2 concentration must be made at the same time as the measurements
for VOC concentration.
iii. If necessary, determine
the exhaust flowrate of the stationary internal combustion engine
exhaust;
(3) Method 2 or 2C of 40 CFR
60, appendix A-1 or Method 19 of 40 CFR part 60, appendix A-7
(c) Measurements to determine
the exhaust flowrate must be made (1) at the same time as the
measurement for VOC concentration or, alternatively (2) according
to the option in Section 11.1.2 of Method 1A of 40 CFR part 60,
Appendix A-1, if applicable.
iv. If necessary, measure
moisture content of the stationary internal combustion engine
exhaust at the sampling port location; and
(4) Method 4 of 40 CFR part
60, appendix A-3, Method 320 of 40 CFR part 63, appendix A,
e or ASTM Method D6348-03 d e
(d) Measurements to determine
moisture must be made at the same time as the measurement for VOC
concentration.
v. Measure VOC at the exhaust
of the stationary internal combustion engine; if using a control
device, the sampling site must be located at the outlet of the
control device
(5) Methods 25A and 18 of 40
CFR part 60, appendices A-6 and A-7, Method 25A with the use of a
hydrocarbon cutter as described in 40 CFR 1065.265, Method 18 of 40
CFR part 60, appendix A-6,c e Method 320 of 40 CFR part 63,
appendix A, e or ASTM Method D6348-03 d e
(e) Results of this test
consist of the average of the three 1-hour or longer runs.
a Also, you may petition the
Administrator for approval to use alternative methods for portable
analyzer.
b You may use ASME PTC
19.10-1981, Flue and Exhaust Gas Analyses, for measuring the O2
content of the exhaust gas as an alternative to EPA Method 3B. AMSE
PTC 19.10-1981 incorporated by reference, see 40 CFR 60.17
c You may use EPA Method 18 of 40
CFR part 60, appendix A-6, provided that you conduct an adequate
pre-survey test prior to the emissions test, such as the one
described in OTM 11 on EPA's website
(http://www.epa.gov/ttn/emc/prelim/otm11.pdf).
d Incorporated by reference; see
40 CFR 60.17.
e You must meet the requirements
in § 60.4245(d).
[85 FR 63408, Oct. 7, 2020]
Table 3 to Subpart JJJJ of Part 60 - Applicability of General Provisions to Subpart JJJJ
40:8.0.1.1.1.36.279.20.53 :
Table 3 to Subpart JJJJ of Part 60 - Applicability of General
Provisions to Subpart JJJJ
[As stated in § 60.4246, you must
comply with the following applicable General Provisions]
General provisions
citation
Subject of citation
Applies to subpart
Explanation
§ 60.1
General applicability of the
General Provisions
Yes
§ 60.2
Definitions
Yes
Additional terms defined in §
60.4248.
§ 60.3
Units and abbreviations
Yes
§ 60.4
Address
Yes
§ 60.5
Determination of construction
or modification
Yes
§ 60.6
Review of plans
Yes
§ 60.7
Notification and
Recordkeeping
Yes
Except that § 60.7 only
applies as specified in § 60.4245.
§ 60.8
Performance tests
Yes
Except that § 60.8 only
applies to owners and operators who are subject to performance
testing in subpart JJJJ.
§ 60.9
Availability of
information
Yes
§ 60.10
State Authority
Yes
§ 60.11
Compliance with standards and
maintenance requirements
Yes
Requirements are specified in
subpart JJJJ.
§ 60.12
Circumvention
Yes
§ 60.13
Monitoring requirements
No
§ 60.14
Modification
Yes
§ 60.15
Reconstruction
Yes
§ 60.16
Priority list
Yes
§ 60.17
Incorporations by
reference
Yes
§ 60.18
General control device
requirements
No
§ 60.19
General notification and
reporting requirements
Yes
Table 4 to Subpart JJJJ of Part 60 - Applicability of Mobile Source Provisions for Manufacturers Participating in the Voluntary Certification Program and Certifying Stationary SI ICE to Emission Standards in Table 1 of Subpart JJJJ
40:8.0.1.1.1.36.279.20.54 :
Table 4 to Subpart JJJJ of Part 60 - Applicability of Mobile Source
Provisions for Manufacturers Participating in the Voluntary
Certification Program and Certifying Stationary SI ICE to Emission
Standards in Table 1 of Subpart JJJJ
[As stated in § 60.4247, you must
comply with the following applicable mobile source provisions if
you are a manufacturer participating in the voluntary certification
program and certifying stationary SI ICE to emission standards in
Table 1 of subpart JJJJ]
Mobile source provisions
citation
Subject of citation
Applies to subpart
Explanation
1048 subpart
A
Overview and
Applicability
Yes
1048 subpart
B
Emission Standards and Related
Requirements
Yes
Except for the specific
sections below.
1048.101
Exhaust Emission
Standards
No
1048.105
Evaporative Emission
Standards
No
1048.110
Diagnosing Malfunctions
No
1048.140
Certifying Blue Sky Series
Engines
No
1048.145
Interim Provisions
No
1048 subpart
C
Certifying Engine
Families
Yes
Except for the specific
sections below.
1048.205(b)
AECD reporting
Yes
1048.205(c)
OBD Requirements
No
1048.205(n)
Deterioration Factors
Yes
Except as indicated in
60.4247(c).
1048.205(p)(1)
Deterioration Factor
Discussion
Yes
1048.205(p)(2)
Liquid Fuels as they
require
No
1048.240(b)(c)(d)
Deterioration Factors
Yes
1048 subpart
D
Testing Production-Line
Engines
Yes
1048 subpart
E
Testing In-Use Engines
No
1048 subpart
F
Test Procedures
Yes
1065.5(a)(4)
Raw sampling (refers reader
back to the specific emissions regulation for guidance)
Yes
1048 subpart
G
Compliance Provisions
Yes
1048 subpart
H
Reserved
1048 subpart
I
Definitions and Other
Reference Information
Yes
1048 appendix I
and II
Yes
1065 (all
subparts)
Engine Testing Procedures
Yes
Except for the specific
section below.
1065.715
Test Fuel Specifications for
Natural Gas
No
1068 (all
subparts)
General Compliance Provisions
for Nonroad Programs
Yes
Except for the specific
sections below.
1068.245
Hardship Provisions for
Unusual Circumstances
No
1068.250
Hardship Provisions for
Small-Volume Manufacturers
No
1068.255
Hardship Provisions for
Equipment Manufacturers and Secondary Engine Manufacturers
No
Table 1 to Subpart KKKK of Part 60 - Nitrogen Oxide Emission Limits for New Stationary Combustion Turbines
40:8.0.1.1.1.37.287.27.55 :
Table 1 to Subpart KKKK of Part 60 - Nitrogen Oxide Emission Limits
for New Stationary Combustion Turbines
Combustion turbine type
Combustion turbine heat input
at peak load
(HHV)
NOX emission standard
New turbine firing
natural gas, electric generating
≤ 50 MMBtu/h
42 ppm at 15 percent O2 or 290
ng/J of useful output (2.3 lb/MWh).
New turbine firing
natural gas, mechanical drive
≤ 50 MMBtu/h
100 ppm at 15 percent O2 or
690 ng/J of useful output (5.5 lb/MWh).
New turbine firing
natural gas
> 50 MMBtu/h and ≤ 850
MMBtu/h
25 ppm at 15 percent O2 or 150
ng/J of useful output (1.2 lb/MWh).
New, modified, or
reconstructed turbine firing natural gas
> 850 MMBtu/h
15 ppm at 15 percent O2 or 54
ng/J of useful output (0.43 lb/MWh)
New turbine firing
fuels other than natural gas, electric generating
≤ 50 MMBtu/h
96 ppm at 15 percent O2 or 700
ng/J of useful output (5.5 lb/MWh).
New turbine firing
fuels other than natural gas, mechanical drive
≤ 50 MMBtu/h
150 ppm at 15 percent O2 or
1,100 ng/J of useful output (8.7 lb/MWh).
New turbine firing
fuels other than natural gas
> 50 MMBtu/h and ≤ 850
MMBtu/h
74 ppm at 15 percent O2 or 460
ng/J of useful output (3.6 lb/MWh).
New, modified, or
reconstructed turbine firing fuels other than natural gas
> 850 MMBtu/h
42 ppm at 15 percent O2 or 160
ng/J of useful output (1.3 lb/MWh).
Modified or
reconstructed turbine
≤ 50 MMBtu/h
150 ppm at 15 percent O2 or
1,100 ng/J of useful output (8.7 lb/MWh).
Modified or
reconstructed turbine firing natural gas
> 50 MMBtu/h and ≤ 850
MMBtu/h
42 ppm at 15 percent O2 or 250
ng/J of useful output (2.0 lb/MWh).
Modified or
reconstructed turbine firing fuels other than natural gas
> 50 MMBtu/h and ≤ 850
MMBtu/h
96 ppm at 15 percent O2 or 590
ng/J of useful output (4.7 lb/MWh).
Turbines located
north of the Arctic Circle (latitude 66.5 degrees north), turbines
operating at less than 75 percent of peak load, modified and
reconstructed offshore turbines, and turbine operating at
temperatures less than 0 °F
≤ 30 MW output
150 ppm at 15 percent O2 or
1,100 ng/J of useful output (8.7 lb/MWh).
Turbines located
north of the Arctic Circle (latitude 66.5 degrees north), turbines
operating at less than 75 percent of peak load, modified and
reconstructed offshore turbines, and turbine operating at
temperatures less than 0 °F
> 30 MW output
96 ppm at 15 percent O2 or 590
ng/J of useful output (4.7 lb/MWh).
Heat recovery
units operating independent of the combustion turbine
All sizes
54 ppm at 15 percent O2 or 110
ng/J of useful output (0.86 lb/MWh).
Table 1 to Subpart LLLL of Part 60 - Emission Limits and Standards for New Fluidized Bed Sewage Sludge Incineration Units
40:8.0.1.1.1.38.298.37.56 :
Table 1 to Subpart LLLL of Part 60 - Emission Limits and Standards
for New Fluidized Bed Sewage Sludge Incineration Units
For the air pollutant
You must meet this emission
limit a
Using these
averaging methods and
minimum sampling
volumes or durations
And determining
compliance using this method
Particulate
matter
9.6 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 5 at
40 CFR part 60, appendix A-3; Method 26A or Method 29 at 40 CFR
part 60, appendix A-8).
Hydrogen
chloride
0.24 parts per million by dry
volume
3-run average (Collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 26A
at 40 CFR part 60, appendix A-8).
Carbon
monoxide
27 parts per million by dry
volume
24-hour block average (using
1-hour averages of data). For determining compliance with the
carbon monoxide concentration limit using carbon monoxide CEMS, the
correction to 7 percent oxygen does not apply during periods of
startup or shutdown. Use the measured carbon monoxide concentration
without correcting for oxygen concentration in averaging with other
carbon monoxide concentrations (corrected to 7 percent oxygen) to
determine the 24-hour average value
Continuous emissions
monitoring system. (Performance Specification 4B of this part,
using a low-range span of 100 ppm and a high-range span of 1000
ppm, and a RA of 0.5 ppm instead of 5 ppm specified in section
13.2. For the cylinder gas audit of Procedure 1, ±15% or 0.5
whichever is greater).
Dioxins/furans
(total mass basis); or
Dioxins/furans (toxic equivalency basis) b
0.013 nanograms per dry
standard cubic meter (total mass basis); or
0.0044 nanograms per dry standard cubic meter (toxic equivalency
basis)
3-run average (collect a
minimum volume of 3 dry standard cubic meters per run)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Mercury
0.0010 milligrams per dry
standard cubic meter
3-run average (For Method 29
and ASTM D6784-02 (Reapproved 2008), c collect a minimum
volume of 3 dry standard cubic meters per run. For Method 30B,
collect a minimum sample as specified in Method 30B at 40 CFR part
60, appendix A-8)
Performance test (Method 29 at
40 CFR part 60, appendix A-8; Method 30B at 40 CFR part 60,
appendix A-8; or ASTM D6784-02 (Reapproved 2008). c
Oxides of
nitrogen
30 parts per million by dry
volume
3-run average (Collect sample
for a minimum duration of one hour per run)
Performance test (Method 7 or
7E at 40 CFR part 60, appendix A-4).
Sulfur
dioxide
5.3 parts per million by dry
volume
3-run average (For Method 6,
collect a minimum volume of 100 liters per run. For Method 6C,
sample for a minimum duration of one hour per run)
Performance test (Method 6 or
6C at 40 CFR part 40, appendix A-4; or ANSI/ASME PTC 19.10-1981.
c
Cadmium
0.0011 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 29 at
40 CFR part 60, appendix A-8). Use GFAAS or ICP/MS for the
analytical finish.
Lead
0.00062 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 3 dry standard cubic meters per run)
Performance test (Method 29 at
40 CFR part 60, appendix A-8. Use GFAAS or ICP/MS for the
analytical finish.
Fugitive emissions
from ash handling
Visible emissions of
combustion ash from an ash conveying system (including conveyor
transfer points) for no more than 5 percent of the hourly
observation period
Three 1-hour observation
periods
Visible emission test (Method
22 of appendix A-7 of this part).
a All emission limits are
measured at 7 percent oxygen, dry basis at standard conditions.
b You have the option to comply
with either the dioxin/furan emission limit on a total mass basis
or the dioxin/furan emission limit on a toxic equivalency
basis.
c Incorporated by reference, see
§ 60.17.
Table 2 to Subpart LLLL of Part 60 - Emission Limits and Standards for New Multiple Hearth Sewage Sludge Incineration Units
40:8.0.1.1.1.38.298.37.57 :
Table 2 to Subpart LLLL of Part 60 - Emission Limits and Standards
for New Multiple Hearth Sewage Sludge Incineration Units
For the air pollutant
You must meet this emission
limit a
Using these averaging methods
and minimum sampling volumes or durations
And determining compliance
using this method
Particulate
matter
60 milligrams per dry standard
cubic meter
3-run average (collect a
minimum volume of 0.75 dry standard cubic meters per run)
Performance test (Method 5 at
40 CFR part 60, appendix A-3; Method 26A or Method 29 at 40 CFR
part 60, appendix A-8).
Hydrogen
chloride
1.2 parts per million by dry
volume
3-run average (For Method 26,
collect a minimum volume of 200 liters per run. For Method 26A,
collect a minimum volume of 1 dry standard cubic meters per
run)
Performance test (Method 26 or
26A at 40 CFR part 60, appendix A-8).
Carbon
monoxide
52 parts per million by dry
volume
24-hour block average (using
1-hour averages of data)
Continuous emissions
monitoring system. (Performance Specification 4B of this part,
using a low-range span of 100 ppm and a high-range span of 1000
ppm, and a relative accuracy of 0.5 ppm instead of 5 ppm specified
in section 13.2. For the cylinder gas audit of Procedure 1, ±15% or
0.5 whichever is greater).
Dioxins/furans
(total mass basis); or
Dioxins/furans (toxic equivalency basis) b
0.045 nanograms per dry
standard cubic meter (total mass basis); or
0.0022 nanograms per dry standard cubic meter (toxic equivalency
basis)
3-run average (collect a
minimum volume of 3 dry standard cubic meters per run)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Mercury
0.15 milligrams per dry
standard cubic meter
3-run average (For Method 29
and ASTM D6784-02 (Reapproved 2008), c collect a minimum
volume of 1 dry standard cubic meters per run. For Method 30B,
collect a minimum sample as specified in Method 30B at 40 CFR part
60, appendix A-8)
Performance test (Method 29 at
40 CFR part 60, appendix A-8; Method 30B at 40 CFR part 60,
appendix A-8; or ASTM D6784-02 (Reapproved 2008). c
Oxides of
nitrogen
210 parts per million by dry
volume
3-run average (Collect sample
for a minimum duration of one hour per run)
Performance test (Method 7 or
7E at 40 CFR part 60, appendix A-4).
Sulfur
dioxide
26 parts per million by dry
volume
3-run average (For Method 6,
collect a minimum volume of 200 liters per run. For Method 6C,
collect sample for a minimum duration of one hour per run)
Performance test (Method 6 or
6C at 40 CFR part 40, appendix A-4; or ANSI/ASME PTC 19.10-1981.
c
Cadmium
0.0024 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 29 at
40 CFR part 60, appendix A-8). Use GFAAS or ICP/MS for the
analytical finish.
Lead
0.0035 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 29 at
40 CFR part 60, appendix A-8. Use GFAAS or ICP/MS for the
analytical finish.
Fugitive emissions
from ash handling
Visible emissions of
combustion ash from an ash conveying system (including conveyor
transfer points) for no more than 5 percent of the hourly
observation period
Three 1-hour observation
periods
Visible emission test (Method
22 of appendix A-7 of this part).
a All emission limits are
measured at 7 percent oxygen, dry basis at standard conditions.
b You have the option to comply
with either the dioxin/furan emission limit on a total mass basis
or the dioxin/furan emission limit on a toxic equivalency
basis.
c Incorporated by reference, see
§ 60.17.
Table 3 to Subpart LLLL of Part 60 - Operating Parameters for New Sewage Sludge Incineration Units a
40:8.0.1.1.1.38.298.37.58 :
Table 3 to Subpart LLLL of Part 60 - Operating Parameters for New
Sewage Sludge Incineration Units a
For these
operating parameters
You must
establish these operating limits
And monitor using
these minimum frequencies
Data measurement
Data
recording b
Data
averaging period for compliance
All
sewage sludge incineration units
Combustion chamber
operating temperature or afterburner temperature
Minimum combustion chamber
operating temperature or afterburner temperature
Continuous
Every 15 minutes
12-hour block.
Fugitive emissions
from ash handling
Site-specific operating
requirements
Not applicable
Not applicable
Not applicable.
Scrubber
Pressure drop
across each wet scrubber
Minimum pressure drop
Continuous
Every 15 minutes
12-hour block.
Scrubber liquid
flow rate
Minimum flow rate
Continuous
Every 15 minutes
12-hour block.
Scrubber liquid
pH
Minimum pH
Continuous
Every 15 minutes
3-hour block.
Fabric Filter
Alarm time of the
bag leak detection system alarm
Maximum alarm time
of the bag leak detection system alarm (this operating limit is
provided in § 60.4850 and is not established on a site-specific
basis).
Electrostatic precipitator
Secondary voltage
of the electrostatic precipitator collection plates
Minimum power input to the
electrostatic precipitator collection plates
Continuous
Hourly
12-hour block.
Secondary amperage
of the electrostatic precipitator collection plates
Effluent water
flow rate at the outlet of the electrostatic precipitator
Minimum effluent water flow
rate at the outlet of the electrostatic precipitator
Hourly
Hourly
12-hour block.
Activated carbon injection
Mercury sorbent
injection rate
Minimum mercury sorbent
injection rate
Hourly
Hourly
12-hour block.
Dioxin/furan
sorbent injection rate
Minimum dioxin/furan sorbent
injection rate
Carrier gas flow
rate or carrier gas pressure drop
Minimum carrier gas flow rate
or minimum carrier gas pressure drop
Continuous
Every 15 minutes
12-hour block.
a As specified in § 60.4870, you
may use a continuous emissions monitoring system or continuous
automated sampling system in lieu of establishing certain operating
limits.
b This recording time refers to
the minimum frequency that the continuous monitor or other
measuring device initially records data. For all data recorded
every 15 minutes, you must calculate hourly arithmetic averages.
For all parameters, you use hourly averages to calculate the
12-hour or 3-hour block average specified in this table for
demonstrating compliance. You maintain records of 1-hour
averages.
Table 4 to Subpart LLLL of Part 60 - Toxic Equivalency Factors
40:8.0.1.1.1.38.298.37.59 :
Table 4 to Subpart LLLL of Part 60 - Toxic Equivalency Factors
Dioxin/furan isomer
Toxic
equivalency
factor
2,3,7,8-tetrachlorinated dibenzo-p-dioxin
1
1,2,3,7,8-pentachlorinated dibenzo-p-dioxin
1
1,2,3,4,7,8-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,7,8,9-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,6,7,8-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,4,6,7,8-heptachlorinated dibenzo-p-dioxin
0.01
octachlorinated
dibenzo-p-dioxin
0.0003
2,3,7,8-tetrachlorinated dibenzofuran
0.1
2,3,4,7,8-pentachlorinated dibenzofuran
0.3
1,2,3,7,8-pentachlorinated dibenzofuran
0.03
1,2,3,4,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,6,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,7,8,9-hexachlorinated dibenzofuran
0.1
2,3,4,6,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,4,6,7,8-heptachlorinated dibenzofuran
0.01
1,2,3,4,7,8,9-heptachlorinated dibenzofuran
0.01
octachlorinated
dibenzofuran
0.0003
Table 5 to Subpart LLLL of Part 60 - Summary of Reporting Requirements for New Sewage Sludge Incineration Units a
40:8.0.1.1.1.38.298.37.60 :
Table 5 to Subpart LLLL of Part 60 - Summary of Reporting
Requirements for New Sewage Sludge Incineration Units a
Report
Due date
Contents
Reference
Notification of
construction
Prior to commencing
construction
1. Statement of intent to
construct
2. Anticipated date of commencement of construction.
3. Documentation for siting requirements.
4. Anticipated date of initial startup.
§ 60.4915(a).
Notification of
initial startup
Prior to initial startup
1. Maximum design dry sewage
sludge burning capacity
2. Anticipated and permitted maximum feed rate.
3. If applicable, the petition for site-specific operating
limits.
4. Anticipated date of initial startup.
5. Site-specific monitoring plan.
6. The site-specific monitoring plan for your ash handling
system.
§ 60.4915(b).
Initial compliance
report
No later than 60 days
following the initial performance test
1. Company name and
address
2. Statement by a responsible official, with that official's name,
title, and signature, certifying the accuracy of the content of the
report.
3. Date of report.
4. Complete test report for the initial performance test.
5. Results of CMS b performance evaluation.
6. The values for the site-specific operating limits and the
calculations and methods, as applicable, used to establish each
operating limit.
7. Documentation of installation of bag leak detection system for
fabric filter.
8. Results of initial air pollution control device inspection,
including a description of repairs.
§ 60.4915(c).
Annual compliance
report
No later than 12 months
following the submission of the initial compliance report;
subsequent reports are to be submitted no more than 12 months
following the previous report
1. Company name and
address
2. Statement and signature by responsible official.
3. Date and beginning and ending dates of report.
4. If a performance test was conducted during the reporting period,
the results of the test, including any new operating limits and
associated calculations and the type of activated carbon used, if
applicable.
5. For each pollutant and operating parameter recorded using a CMS,
the highest recorded 3-hour average and the lowest recorded 3-hour
average, as applicable.
6. If no deviations from emission limits, emission standards, or
operating limits occurred, a statement that no deviations
occurred.
7. If a fabric filter is used, the date, time, and duration of
alarms.
8. If a performance evaluation of a CMS was conducted, the results,
including any new operating limits and their associated
calculations.
9. If you met the requirements of § 60.4885(a)(3) and did not
conduct a performance test, include the dates of the last three
performance tests, a comparison to the 50 percent emission limit
threshold of the emission level achieved in the last three
performance tests, and a statement as to whether there have been
any process changes.
10. Documentation of periods when all qualified SSI unit operators
were unavailable for more than 8 hours but less than 2 weeks.
11. Results of annual pollutions control device inspections,
including description of repairs.
12. If there were no periods during which your CMSs had
malfunctions, a statement that there were no periods during which
your CMSs had malfunctions.
13. If there were no periods during which your CMSs were out of
control, a statement that there were no periods during which your
CMSs were out of control.
14. If there were no operator training deviations, a statement that
there were no such deviations.
15. Information on monitoring plan revisions, including a copy of
any revised monitoring plan.
§§ 60.4915(d).
Deviation report
(deviations from emission limits, emission standards, or operating
limits, as specified in § 60.4915(e)(1))
By August 1 of a calendar year
for data collected during the first half of the calendar year; by
February 1 of a calendar year for data collected during the second
half of the calendar year
If using a CMS: 1. Company
name and address
2. Statement by a responsible official.
3. The calendar dates and times your unit deviated from the
emission limits or operating limits.
4. The averaged and recorded data for those dates.
5. Duration and cause of each deviation.
6. Dates, times, and causes for monitor downtime incidents.
7. A copy of the operating parameter monitoring data during each
deviation and any test report that documents the emission
levels.
8. For periods of CMS malfunction or when a CMS was out of control,
you must include the information specified in §
60.4915(e)(3)(viii).
If not using a CMS:
1. Company name and address
2. Statement by a responsible official.
3. The total operating time of each affected SSI.
4. The calendar dates and times your unit deviated from the
emission limits, emission standard, or operating limits.
5. The averaged and recorded data for those dates.
6. Duration and cause of each deviation.
7. A copy of any performance test report that showed a deviation
from the emission limits or standards.
8. A brief description of any malfunction, a description of actions
taken during the malfunction to minimize emissions, and corrective
action taken.
§ 60.4915(e).
Notification of
qualified operator deviation (if all qualified operators are not
accessible for 2 weeks or more)
Within 10 days of
deviation
1. Statement of cause of
deviation
2. Description of actions taken to ensure that a qualified operator
will be available
3. The date when a qualified operator will be accessible.
§ 60.4915(f).
Notification of
status of qualified operator deviation
Every 4 weeks following
notification of deviation
1. Description of actions
taken to ensure that a qualified operator is accessible
2. The date when you anticipate that a qualified operator will be
accessible.
3. Request for approval to continue operation.
§ 60.4915(f).
Notification of
resumed operation following shutdown (due to qualified operator
deviation and as specified in § 60.4835(b)(2)(i)
Within 5 days of obtaining a
qualified operator and resuming operation
1. Notification that you have
obtained a qualified operator and are resuming operation
§ 60.4915(f).
Notification of a
force majeure
As soon as practicable
following the date you first knew, or through due diligence should
have known that the event may cause or caused a delay in conducting
a performance test beyond the regulatory deadline; the notification
must occur before the performance test deadline unless the initial
force majeure or a subsequent force majeure event delays the
notice, and in such cases, the notification must occur as soon as
practicable
1. Description of the force
majeure event
2. Rationale for attributing the delay in conducting the
performance test beyond the regulatory deadline to the force
majeure.
3. Description of the measures taken or to be taken to minimize the
delay.
4. Identification of the date by which you propose to conduct the
performance test.
§ 60.4915(g).
Notification of
intent to start or stop use of a CMS
1 month before starting or
stopping use of a CMS
1. Intent to start or stop use
of a CMS
§ 60.4915(h).
Notification of
intent to conduct a performance test
At least 30 days prior to the
performance test
1. Intent to conduct a
performance test to comply with this subpart
Notification of
intent to conduct a rescheduled performance test
At least 7 days prior to the
date of a rescheduled performance test
1. Intent to conduct a
rescheduled performance test to comply with this subpart
a This table is only a summary,
see the referenced sections of the rule for the complete
requirements.
b CMS means continuous monitoring
system.
Table 1 to Subpart MMMM of Part 60 - Model Rule - Increments of Progress and Compliance Schedules for Existing Sewage Sludge Incineration Units
40:8.0.1.1.1.39.310.53.61 :
Table 1 to Subpart MMMM of Part 60 - Model Rule - Increments of
Progress and Compliance Schedules for Existing Sewage Sludge
Incineration Units
Comply with these increments
of progress
By these dates
a
Increment 1 -
Submit final control plan
(Dates to be specified in
state plan)
Increment 2 -
Final compliance
(Dates to be specified in
state plan) b
a Site-specific schedules can be
used at the discretion of the state.
b The date can be no later than 3
years after the effective date of state plan approval or March 21,
2016 for SSI units that commenced construction on or before October
14, 2010.
Table 2 to Subpart MMMM of Part 60 - Model Rule - Emission Limits and Standards for Existing Fluidized Bed Sewage Sludge Incineration Units
40:8.0.1.1.1.39.310.53.62 :
Table 2 to Subpart MMMM of Part 60 - Model Rule - Emission Limits
and Standards for Existing Fluidized Bed Sewage Sludge Incineration
Units
For the air pollutant
You must meet this emission
limit a
Using these averaging methods
and minimum sampling volumes or
durations
And determining compliance
using this method
Particulate
matter
18 milligrams per dry standard
cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters sample per run)
Performance test (Method 5 at
40 CFR part 60, appendix A-3; Method 26A or Method 29 at 40 CFR
part 60, appendix A-8).
Hydrogen
chloride
0.51 parts per million by dry
volume
3-run average (Collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 26A
at 40 CFR part 60, appendix A-8).
Carbon
monoxide
64 parts per million by dry
volume
3-run average (collect sample
for a minimum duration of one hour per run)
Performance test (Method 10,
10A, or 10B at 40 CFR part 60, appendix A-4).
Dioxins/furans
(total mass basis); or
Dioxins/furans (toxic equivalency basis) b
1.2 nanograms per dry standard
cubic meter (total mass basis); or
0.10 nanograms per dry standard cubic meter (toxic equivalency
basis)
3-run average (collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Mercury
0.037 milligrams per dry
standard cubic meter
3-run average (For Method 29
and ASTM D6784-02 (Reapproved 2008) c, collect a minimum
volume of 1 dry standard cubic meters per run. For Method 30B,
collect a minimum sample as specified in Method 30B at 40 CFR part
60, appendix A-8)
Performance test (Method 29 at
40 CFR part 60, appendix A-8; Method 30B at 40 CFR part 60,
appendix A-8; or ASTM D6784-02 (Reapproved 2008). c
Oxides of
nitrogen
150 parts per million by dry
volume
3-run average (Collect sample
for a minimum duration of one hour per run)
Performance test (Method 7 or
7E at 40 CFR part 60, appendix A-4).
Sulfur
dioxide
15 parts per million by dry
volume
3-run average (For Method 6,
collect a minimum volume of 60 liters per run. For Method 6C,
collect sample for a minimum duration of one hour per run)
Performance test (Method 6 or
6C at 40 CFR part 40, appendix A-4; or ANSI/ASME PTC-19.10-1981.
c
Cadmium
0.0016 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 29 at
40 CFR part 60, appendix A-8). Use GFAAS or ICP/MS for the
analytical finish.
Lead
0.0074 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters sample per run)
Performance test (Method 29 at
40 CFR part 60, appendix A-8. Use GFAAS or ICP/MS for the
analytical finish.
Fugitive emissions
from ash handling
Visible emissions of
combustion ash from an ash conveying system (including conveyor
transfer points) for no more than 5 percent of the hourly
observation period
Three 1-hour observation
periods
Visible emission test (Method
22 of appendix A-7 of this part).
a All emission limits are
measured at 7 percent oxygen, dry basis at standard conditions.
b You have the option to comply
with either the dioxin/furan emission limit on a total mass basis
or the dioxin/furan emission limit on a toxic equivalency
basis.
c Incorporated by reference, see
§ 60.17.
Table 3 to Subpart MMMM of Part 60 - Model Rule - Emission Limits and Standards for Existing Multiple Hearth Sewage Sludge Incineration Units
40:8.0.1.1.1.39.310.53.63 :
Table 3 to Subpart MMMM of Part 60 - Model Rule - Emission Limits
and Standards for Existing Multiple Hearth Sewage Sludge
Incineration Units
For the air pollutant
You must meet this emission
limit a
Using these averaging methods
and
minimum sampling volumes or durations
And determining compliance
using this
method
Particulate
matter
80 milligrams per dry standard
cubic meter
3-run average (collect a
minimum volume of 0.75 dry standard cubic meters per run)
Performance test (Method 5 at
40 CFR part 60, appendix A-3; Method 26A or Method 29 at 40 CFR
part 60, appendix A-8).
Hydrogen
chloride
1.2 parts per million by dry
volume
3-run average (For Method 26,
collect a minimum volume of 200 liters per run. For Method 26A,
collect a minimum volume of 1 dry standard cubic meters per
run)
Performance test (Method 26 or
26A at 40 CFR part 60, appendix A-8).
Carbon
monoxide
3,800 parts per million by dry
volume
3-run average (collect sample
for a minimum duration of one hour per run)
Performance test (Method 10,
10A, or 10B at 40 CFR part 60, appendix A-4).
Dioxins/furans
(total mass basis)
5.0 nanograms per dry standard
cubic meter; or
3-run average (collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 23 at
40 CFR part 60, appendix A-7).
Dioxins/furans
(toxic equivalency basis) b
0.32 nanograms per dry
standard cubic meter
Mercury
0.28 milligrams per dry
standard cubic meter
3-run average (For Method 29
and ASTM D6784-02 (Reapproved 2008), c collect a minimum
volume of 1 dry standard cubic meters per run. For Method 30B,
collect a minimum sample as specified in Method 30B at 40 CFR part
60, appendix A-8)
Performance test (Method 29 at
40 CFR part 60, appendix A-8; Method 30B at 40 CFR part 60,
appendix A-8; or ASTM D6784-02 (Reapproved 2008)).
c
Oxides of
nitrogen
220 parts per million by dry
volume
3-run average (Collect sample
for a minimum duration of one hour per run)
Performance test (Method 7 or
7E at 40 CFR part 60, appendix A-4).
Sulfur
dioxide
26 parts per million by dry
volume
3-run average (For Method 6,
collect a minimum volume of 200 liters per run. For Method 6C,
collect sample for a minimum duration of one hour per run)
Performance test (Method 6 or
6C at 40 CFR part 40, appendix A-4; or ANSI/ASME PTC 19.10-1981).
c
Cadmium
0.095 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 29 at
40 CFR part 60, appendix A-8).
Lead
0.30 milligrams per dry
standard cubic meter
3-run average (collect a
minimum volume of 1 dry standard cubic meters per run)
Performance test (Method 29 at
40 CFR part 60, appendix A-8).
Fugitive emissions
from ash handling
Visible emissions of
combustion ash from an ash conveying system (including conveyor
transfer points) for no more than 5 percent of the hourly
observation period
Three 1-hour observation
periods
Visible emission test (Method
22 of appendix A-7 of this part).
a All emission limits are
measured at 7 percent oxygen, dry basis at standard conditions.
b You have the option to comply
with either the dioxin/furan emission limit on a total mass basis
or the dioxin/furan emission limit on a toxic equivalency
basis.
c Incorporated by reference, see
§ 60.17.
Table 4 to Subpart MMMM of Part 60 - Model Rule - Operating Parameters for Existing Sewage Sludge Incineration Units a
40:8.0.1.1.1.39.310.53.64 :
Table 4 to Subpart MMMM of Part 60 - Model Rule - Operating
Parameters for Existing Sewage Sludge Incineration Units a
For these
operating parameters
You must
establish these operating limits
And monitor using
these minimum frequencies
Data measurement
Data recording
b
Data averaging
period for
compliance
All
sewage sludge incineration units
Combustion chamber
operating temperature (not required if afterburner temperature is
monitored)
Minimum combustion chamber
operating temperature or afterburner temperature
Continuous
Every 15 minutes
12-hour block.
Fugitive emissions
from ash handling
Site-specific operating
requirements
Not applicable
No applicable
Not applicable.
Scrubber
Pressure drop
across each wet scrubber
Minimum pressure drop
Continuous
Every 15 minutes
12-hour block.
Scrubber liquid
flow rate
Minimum flow rate
Continuous
Every 15 minutes
12-hour block.
Scrubber liquid
pH
Minimum pH
Continuous
Every 15 minutes
3-hour block.
Fabric Filter
Alarm time of the
bag leak detection system alarm
Maximum alarm time
of the bag leak detection system alarm (this operating limit is
provided in § 60.4850 and is not established on a site-specific
basis)
Electrostatic precipitator
Secondary voltage
of the electrostatic precipitator collection plates
Minimum power input to the
electrostatic precipitator collection plates
Continuous
Hourly
12-hour block.
Secondary amperage
of the electrostatic precipitator collection plates
Effluent water
flow rate at the outlet of the electrostatic precipitator
Minimum effluent water flow
rate at the outlet of the electrostatic precipitator
Hourly
Hourly
12-hour block.
Activated carbon injection
Mercury sorbent
injection rate
Minimum mercury sorbent
injection rate
Hourly
Hourly
12-hour block.
Dioxin/furan
sorbent injection rate
Minimum dioxin/furan sorbent
injection rate
Carrier gas flow
rate or carrier gas pressure drop
Minimum carrier gas flow rate
or minimum carrier gas pressure drop
Continuous
Every 15 minutes
12-hour block.
Afterburner
Temperature of the
afterburner combustion chamber
Minimum temperature of the
afterburner combustion chamber
Continuous
Every 15 minutes
12-hour block.
a As specified in § 60.5190, you
may use a continuous emissions monitoring system or continuous
automated sampling system in lieu of establishing certain operating
limits.
b This recording time refers to
the minimum frequency that the continuous monitor or other
measuring device initially records data. For all data recorded
every 15 minutes, you must calculate hourly arithmetic averages.
For all parameters, you use hourly averages to calculate the
12-hour or 3-hour block average specified in this table for
demonstrating compliance. You maintain records of 1-hour
averages.
Table 5 to Subpart MMMM of Part 60 - Model Rule - Toxic Equivalency Factors
40:8.0.1.1.1.39.310.53.65 :
Table 5 to Subpart MMMM of Part 60 - Model Rule - Toxic Equivalency
Factors
Dioxin/furan isomer
Toxic
equivalency
factor
2,3,7,8-tetrachlorinated dibenzo-p-dioxin
1
1,2,3,7,8-pentachlorinated dibenzo-p-dioxin
1
1,2,3,4,7,8-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,7,8,9-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,6,7,8-hexachlorinated dibenzo-p-dioxin
0.1
1,2,3,4,6,7,8-heptachlorinated dibenzo-p-dioxin
0.01
octachlorinated
dibenzo-p-dioxin
0.0003
2,3,7,8-tetrachlorinated dibenzofuran
0.1
2,3,4,7,8-pentachlorinated dibenzofuran
0.3
1,2,3,7,8-pentachlorinated dibenzofuran
0.03
1,2,3,4,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,6,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,7,8,9-hexachlorinated dibenzofuran
0.1
2,3,4,6,7,8-hexachlorinated dibenzofuran
0.1
1,2,3,4,6,7,8-heptachlorinated dibenzofuran
0.01
1,2,3,4,7,8,9-heptachlorinated dibenzofuran
0.01
octachlorinated
dibenzofuran
0.0003
Table 6 to Subpart MMMM of Part 60 - Model Rule - Summary of Reporting Requirements for Existing Sewage Sludge Incineration Units a
40:8.0.1.1.1.39.310.53.66 :
Table 6 to Subpart MMMM of Part 60 - Model Rule - Summary of
Reporting Requirements for Existing Sewage Sludge Incineration
Units a
Report
Due date
Contents
Reference
Increments of
progress report
No later than 10 business days
after the compliance date for the increment
1. Final control plan
including air pollution control device descriptions, process
changes, type of waste to be burned, and the maximum design sewage
sludge burning capacity
2. Notification of any failure to meet an increment of
progress.
3. Notification of any closure.
§ 60.5235(a).
Initial compliance
report
No later than 60 days
following the initial performance test
1. Company name and
address
2. Statement by a responsible official, with that official's name,
title, and signature, certifying the accuracy of the content of the
report
§ 60.5235(b).
3. Date of report
4. Complete test report for
the initial performance test
5. Results of CMS b
performance evaluation
6. The values for the
site-specific operating limits and the calculations and methods
used to establish each operating limit
7. Documentation of
installation of bag leak detection system for fabric filter
8. Results of initial air
pollution control device inspection, including a description of
repairs
9. The site-specific
monitoring plan required under § 60.5200
10. The site-specific
monitoring plan for your ash handling system required under §
60.5200
Annual compliance
report
No later than 12 months
following the submission of the initial compliance report;
subsequent reports are to be submitted no more than 12 months
following the previous report
1. Company name and
address
2. Statement and signature by responsible official.
3. Date and beginning and ending dates of report.
4. If a performance test was conducted during the reporting period,
the results of the test, including any new operating limits and
associated calculations and the type of activated carbon used, if
applicable.
§ 60.5235(c).
5. For each pollutant and
operating parameter recorded using a CMS, the highest recorded
3-hour average and the lowest recorded 3-hour average, as
applicable
6. If no deviations from
emission limits, emission standards, or operating limits occurred,
a statement that no deviations occurred
7. If a fabric filter is used,
the date, time, and duration of alarms
8. If a performance evaluation
of a CMS was conducted, the results, including any new operating
limits and their associated calculations
9. If you met the requirements
of § 60.5205(a)(3) and did not conduct a performance test, include
the dates of the last three performance tests, a comparison to the
50 percent emission limit threshold of the emission level achieved
in the last three performance tests, and a statement as to whether
there have been any process changes
10. Documentation of periods
when all qualified SSI unit operators were unavailable for more
than 8 hours but less than 2 weeks
11. Results of annual
pollutions control device inspections, including description of
repairs
12. If there were no periods
during which your CMSs had malfunctions, a statement that there
were no periods during which your CMSs had malfunctions
13. If there were no periods
during which your CMSs were out of control, a statement that there
were no periods during which your CMSs were out of control
14. If there were no operator
training deviations, a statement that there were no such
deviations
15. Information on monitoring
plan revisions, including a copy of any revised monitoring
plan
Deviation report
(deviations from emission limits, emission standards, or operating
limits, as specified in § 60.5235(e)(1))
By August 1 of a calendar year
for data collected during the first half of the calendar year; by
February 1 of a calendar year for data collected during the second
half of the calendar year
If using a CMS:
1. Company name and address.
2. Statement by a responsible official.
3. The calendar dates and times your unit deviated from the
emission limits or operating limits.
4. The averaged and recorded data for those dates.
5. Duration and cause of each deviation.
§ 60.5235(d).
6. Dates, times, and causes
for monitor downtime incidents
7. A copy of the operating
parameter monitoring data during each deviation and any test report
that documents the emission levels
8. For periods of CMS
malfunction or when a CMS was out of control, you must include the
information specified in § 60.5235(d)(3)(viii)
If not using a CMS:
1. Company name and
address
2. Statement by a responsible
official
3. The total operating time of
each affected SSI
4. The calendar dates and
times your unit deviated from the emission limits, emission
standard, or operating limits
5. The averaged and recorded
data for those dates
6. Duration and cause of each
deviation
7. A copy of any performance
test report that showed a deviation from the emission limits or
standards
8. A brief description of any
malfunction, a description of actions taken during the malfunction
to minimize emissions, and corrective action taken
Notification of
qualified operator deviation (if all qualified operators are not
accessible for 2 weeks or more)
Within 10 days of
deviation
1. Statement of cause of
deviation
2. Description of actions taken to ensure that a qualified operator
will be available.
3. The date when a qualified operator will be accessible.
§ 60.5235(e).
Notification of
status of qualified operator deviation
Every 4 weeks following
notification of deviation
1. Description of actions
taken to ensure that a qualified operator is accessible
2. The date when you anticipate that a qualified operator will be
accessible.
3. Request for approval to continue operation.
§ 60.5235(e).
Notification of
resumed operation following shutdown (due to qualified operator
deviation and as specified in § 60.5155(b)(2)(i)
Within five days of obtaining
a qualified operator and resuming operation
1. Notification that you have
obtained a qualified operator and are resuming operation
§ 60.5235(e).
Notification of a
force majeure
As soon as practicable
following the date you first knew, or through due diligence should
have known that the event may cause or caused a delay in conducting
a performance test beyond the regulatory deadline; the notification
must occur before the performance test deadline unless the initial
force majeure or a subsequent force majeure event delays the
notice, and in such cases, the notification must occur as soon as
practicable
1. Description of the force
majeure event
2. Rationale for attributing the delay in conducting the
performance test beyond the regulatory deadline to the force
majeure
3. Description of the measures taken or to be taken to minimize the
delay.
4. Identification of the date by which you propose to conduct the
performance test.
§ 60.5235(f).
Notification of
intent to start or stop use of a CMS
1 month before starting or
stopping use of a CMS
1. Intent to start or stop use
of a CMS
§ 60.5235(g).
Notification of
intent to conduct a performance test
At least 30 days prior to the
performance test
1. Intent to conduct a
performance test to comply with this subpart
Notification of
intent to conduct a rescheduled performance test
At least 7 days prior to the
date of a rescheduled performance test
1. Intent to conduct a
rescheduled performance test to comply with this subpart
a This table is only a summary,
see the referenced sections of the rule for the complete
requirements.
b CMS means continuous monitoring
system.
Table 1 to Subpart OOOO of Part 60 - Required Minimum Initial SO2 Emission Reduction Efficiency (Zi)
40:8.0.1.1.1.41.310.29.67 :
Table 1 to Subpart OOOO of Part 60 - Required Minimum Initial SO2
Emission Reduction Efficiency (Zi)
H2S content of
acid gas (Y), %
Sulfur feed rate
(X), LT/D
2.0 ≤ X ≤ 5.0
5.0 < X ≤ 15.0
15.0 < X ≤ 300.0
X > 300.0
Y ≥ 50
79.0
88.51X
0.0101Y 0.0125 or 99.9, whichever is
smaller.
20 ≤ Y <
50
79.0
88.51X
0.0101Y 0.0125 or 97.9, whichever is
smaller
97.9
10 ≤ Y <
20
79.0
88.51X 0.0101Y
0.0125 or 93.5, whichever is smaller
93.5
93.5
Y < 10
79.0
79.0
79.0
79.0
[78 FR 58447, Sept. 23, 2013]
Table 2 to Subpart OOOO of Part 60 - Required Minimum SO2 Emission Reduction Efficiency (Zc)
40:8.0.1.1.1.41.310.29.68 :
Table 2 to Subpart OOOO of Part 60 - Required Minimum SO2 Emission
Reduction Efficiency (Zc)
H2S content of
acid gas (Y), %
Sulfur feed rate
(X), LT/D
2.0 ≤ X ≤ 5.0
5.0 < X ≤ 15.0
15.0 < X ≤ 300.0
X > 300.0
Y ≥ 50
74.0
85.35X
0.0144Y 0.0128 or 99.9, whichever is
smaller.
20 ≤ Y <
50
74.0
85.35X
0.0144Y 0.0128 or 97.5, whichever is
smaller
97.5
10 ≤ Y <
20
74.0
85.35X 0.0144Y
0.0128 or 90.8, whichever is smaller
90.8
90.8
Y < 10
74.0
74.0
74.0
74.0
X = The sulfur feed rate from the sweetening
unit (i.e., the H2S in the acid gas), expressed as sulfur,
Mg/D(LT/D), rounded to one decimal place.
Y = The sulfur content of the acid gas from
the sweetening unit, expressed as mole percent H2S (dry basis)
rounded to one decimal place.
Z = The minimum required sulfur dioxide
(SO2) emission reduction efficiency, expressed as percent carried
to one decimal place. Zi refers to the reduction efficiency
required at the initial performance test. Zc refers to the
reduction efficiency required on a continuous basis after
compliance with Zi has been demonstrated.
[78 FR 58447, Sept. 23, 2013]
Table 3 to Subpart OOOO of Part 60 - Applicability of General Provisions to Subpart OOOO
40:8.0.1.1.1.41.310.29.69 :
Table 3 to Subpart OOOO of Part 60 - Applicability of General
Provisions to Subpart OOOO
As stated in § 60.5425, you must comply with the following
applicable General Provisions:
General
provisions
citation
Subject of citation
Applies to
subpart?
Explanation
§ 60.1
General applicability of the
General Provisions
Yes.
§ 60.2
Definitions
Yes
Additional terms defined in §
60.5430.
§ 60.3
Units and abbreviations
Yes.
§ 60.4
Address
Yes.
§ 60.5
Determination of construction
or modification
Yes.
§ 60.6
Review of plans
Yes.
§ 60.7
Notification and record
keeping
Yes
Except that § 60.7 only
applies as specified in § 60.5420(a).
§ 60.8
Performance tests
Yes
Performance testing is
required for control devices used on storage vessels and
centrifugal compressors.
§ 60.9
Availability of
information
Yes.
§ 60.10
State authority
Yes.
§ 60.11
Compliance with standards and
maintenance requirements
No
Requirements are specified in
subpart OOOO.
§ 60.12
Circumvention
Yes.
§ 60.13
Monitoring requirements
Yes
Continuous monitors are
required for storage vessels.
§ 60.14
Modification
Yes.
§ 60.15
Reconstruction
Yes.
Except that § 60.15(d) does
not apply to gas wells, pneumatic controllers, centrifugal
compressors, reciprocating compressors or storage vessels.
§ 60.16
Priority list
Yes.
§ 60.17
Incorporations by
reference
Yes.
§ 60.18
General control device
requirements
Yes
Except that the period of
visible emissions shall not exceed a total of 1 minute during any
15-minute period instead of 5 minutes during any 2 consecutive
hours as required in § 60.18(c).
§ 60.19
General notification and
reporting requirement
Yes.
[77 FR 49542, Aug. 16, 2012, as amended at 81 FR 35898, June 3,
2016]
Table 1 to Subpart OOOOa of Part 60 - Required Minimum Initial SO2 Emission Reduction Efficiency (Zi)
40:8.0.1.1.1.42.310.35.70 :
Table 1 to Subpart OOOOa of Part 60 - Required Minimum Initial SO2
Emission Reduction Efficiency (Zi)
H2S content of
acid gas (Y), %
Sulfur feed rate
(X), LT/D
2.0 < X < 5.0
5.0 < X < 15.0
15.0 < X < 300.0
X > 300.0
Y > 50
79.0
88.51X
0.0101Y 0.0125 or 99.9, whichever is
smaller.
20 < Y <
50
79.0
88.51X
0.0101Y 0.0125 or 97.9, whichever is
smaller
97.9
10 < Y <
20
79.0
88.51X 0.0101Y
0.0125 or 93.5, whichever is smaller
93.5
93.5
Y < 10
79.0
79.0
79.0
79.0
Table 2 to Subpart OOOOa of Part 60 - Required Minimum SO2 Emission Reduction Efficiency (Zc)
40:8.0.1.1.1.42.310.35.71 :
Table 2 to Subpart OOOOa of Part 60 - Required Minimum SO2 Emission
Reduction Efficiency (Zc)
H2S content of
acid gas (Y), %
Sulfur feed rate
(X), LT/D
2.0 < X < 5.0
5.0 < X < 15.0
15.0 < X < 300.0
X > 300.0
Y > 50
74.0
85.35X
0.0144Y 0.0128 or 99.9, whichever is
smaller.
20 < Y <
50
74.0
85.35X
0.0144Y 0.0128 or 97.5, whichever is
smaller
97.5
10 < Y <
20
74.0
85.35X 0.0144Y
0.0128 or 90.8, whichever is smaller
90.8
90.8
Y < 10
74.0
74.0
74.0
74.0
X = The sulfur feed rate from the sweetening unit (i.e.,
the H2S in the acid gas), expressed as sulfur, Mg/D(LT/D), rounded
to one decimal place.
Y = The sulfur content of the acid gas from the sweetening unit,
expressed as mole percent H2S (dry basis) rounded to one decimal
place.
Z = The minimum required sulfur dioxide (SO2) emission reduction
efficiency, expressed as percent carried to one decimal place. Zi
refers to the reduction efficiency required at the initial
performance test. Zc refers to the reduction efficiency required on
a continuous basis after compliance with Zi has been
demonstrated.
As stated in § 60.5425a, you must comply with the following
applicable General Provisions:
Table 3 to Subpart OOOOa of Part 60 - Applicability of General Provisions to Subpart OOOOa
40:8.0.1.1.1.42.310.35.72 :
Table 3 to Subpart OOOOa of Part 60 - Applicability of General
Provisions to Subpart OOOOa
General provisions
citation
Subject of citation
Applies to subpart?
Explanation
§ 60.1
General applicability of the
General Provisions
Yes
§ 60.2
Definitions
Yes
Additional terms defined in §
60.5430a.
§ 60.3
Units and abbreviations
Yes
§ 60.4
Address
Yes
§ 60.5
Determination of construction
or modification
Yes
§ 60.6
Review of plans
Yes
§ 60.7
Notification and record
keeping
Yes
Except that § 60.7 only
applies as specified in § 60.5420a(a).
§ 60.8
Performance tests
Yes
Except that the format of
performance test reports is described in § 60.5420a(b). Performance
testing is required for control devices used on storage vessels,
centrifugal compressors, and pneumatic pumps, except that
performance testing is not required for a control device used
solely on pneumatic pump(s).
§ 60.9
Availability of
information
Yes
§ 60.10
State authority
Yes
§ 60.11
Compliance with standards and
maintenance requirements
No
Requirements are specified in
subpart OOOOa.
§ 60.12
Circumvention
Yes
§ 60.13
Monitoring requirements
Yes
Continuous monitors are
required for storage vessels.
§ 60.14
Modification
Yes
To the extent any provision in
§ 60.14 conflicts with specific provisions in subpart OOOOa, it is
superseded by subpart OOOOa provisions.
§ 60.15
Reconstruction
Yes
Except that § 60.15(d) does
not apply to wells, pneumatic controllers, pneumatic pumps,
centrifugal compressors, reciprocating compressors, storage
vessels, or the collection of fugitive emissions components at a
well site or the collection of fugitive emissions components at a
compressor station.
§ 60.16
Priority list
Yes
§ 60.17
Incorporations by
reference
Yes
§ 60.18
General control device and
work practice requirements
Yes
§ 60.19
General notification and
reporting requirement
Yes
[81 FR 35898, June 3, 2016, as amended at 85 FR 57460, Sept. 15,
2020]
Table 1 of Subpart TTTT of Part 60 - CO2 Emission Standards for Affected Steam Generating Units and Integrated Gasification Combined Cycle Facilities That Commenced Construction After January 8, 2014 and Reconstruction or Modification After June 18, 2014
40:8.0.1.1.1.45.316.15.73 :
Table 1 of Subpart TTTT of Part 60 - CO2 Emission Standards for
Affected Steam Generating Units and Integrated Gasification
Combined Cycle Facilities That Commenced Construction After January
8, 2014 and Reconstruction or Modification After June 18, 2014
[Note: Numerical values of 1,000 or
greater have a minimum of 3 significant figures and numerical
values of less than 1,000 have a minimum of 2 significant
figures]
Affected EGU
CO2 Emission standard
Newly constructed
steam generating unit or integrated gasification combined cycle
(IGCC)
640 kg CO2/MWh of gross energy
output (1,400 lb CO2/MWh).
Reconstructed
steam generating unit or IGCC that has base load rating of 2,100
GJ/h (2,000 MMBtu/h) or less
910 kg of CO2 per MWh of gross
energy output (2,000 lb CO2/MWh).
Reconstructed
steam generating unit or IGCC that has a base load rating greater
than 2,100 GJ/h (2,000 MMBtu/h)
820 kg of CO2 per MWh of gross
energy output (1,800 lb CO2/MWh).
Modified steam
generating unit or IGCC
A unit-specific emission limit
determined by the unit's best historical annual CO2 emission rate
(from 2002 to the date of the modification); the emission limit
will be no lower than:
1. 1,800 lb CO2/MWh-gross for
units with a base load rating greater than 2,000 MMBtu/h; or
2. 2,000 lb CO2/MWh-gross for
units with a base load rating of 2,000 MMBtu/h or less.
Table 2 of Subpart TTTT of Part 60 - CO2 Emission Standards for Affected Stationary Combustion Turbines That Commenced Construction After January 8, 2014 and Reconstruction After June 18, 2014 (Net Energy Output-Based Standards Applicable as Approved by the Administrator)
40:8.0.1.1.1.45.316.15.74 :
Table 2 of Subpart TTTT of Part 60 - CO2 Emission Standards for
Affected Stationary Combustion Turbines That Commenced Construction
After January 8, 2014 and Reconstruction After June 18, 2014 (Net
Energy Output-Based Standards Applicable as Approved by the
Administrator)
[Note: Numerical values of 1,000 or
greater have a minimum of 3 significant figures and numerical
values of less than 1,000 have a minimum of 2 significant
figures]
Affected EGU
CO2 Emission standard
Newly constructed
or reconstructed stationary combustion turbine that supplies more
than its design efficiency or 50 percent, whichever is less, times
its potential electric output as net-electric sales on both a
12-operating month and a 3-year rolling average basis and combusts
more than 90% natural gas on a heat input basis on a
12-operating-month rolling average basis
450 kg of CO2 per MWh of gross
energy output (1,000 lb CO2/MWh); or
470 kilograms (kg) of CO2 per megawatt-hour (MWh) of net energy
output (1,030 lb/MWh).
Newly constructed
or reconstructed stationary combustion turbine that supplies its
design efficiency or 50 percent, whichever is less, times its
potential electric output or less as net-electric sales on either a
12-operating month or a 3-year rolling average basis and combusts
more than 90% natural gas on a heat input basis on a
12-operating-month rolling average basis
50 kg CO2 per gigajoule (GJ)
of heat input (120 lb CO2/MMBtu).
Newly constructed
and reconstructed stationary combustion turbine that combusts 90%
or less natural gas on a heat input basis on a 12-operating-month
rolling average basis
50 kg CO2/GJ of heat input
(120 lb/MMBtu) to 69 kg CO2/GJ of heat input (160 lb/MMBtu) as
determined by the procedures in § 60.5525.
Table 3 to Subpart TTTT of Part 60 - Applicability of Subpart A of Part 60 (General Provisions) to Subpart TTTT
40:8.0.1.1.1.45.316.15.75 :
Table 3 to Subpart TTTT of Part 60 - Applicability of Subpart A of
Part 60 (General Provisions) to Subpart TTTT
General
provisions
citation
Subject of citation
Applies to subpart TTTT
Explanation
§ 60.1
Applicability
Yes
§ 60.2
Definitions
Yes
Additional terms defined in §
60.5580.
§ 60.3
Units and Abbreviations
Yes
§ 60.4
Address
Yes
Does not apply to information
reported electronically through ECMPS. Duplicate submittals are not
required.
§ 60.5
Determination of construction
or modification
Yes
§ 60.6
Review of plans
Yes
§ 60.7
Notification and
Recordkeeping
Yes
Only the requirements to
submit the notifications in § 60.7(a)(1) and (3) and to keep
records of malfunctions in § 60.7(b), if applicable.
§ 60.8
Performance tests
No
§ 60.9
Availability of
Information
Yes
§ 60.10
State authority
Yes
§ 60.11
Compliance with standards and
maintenance requirements
No
§ 60.12
Circumvention
Yes
§ 60.13
Monitoring requirements
No
All monitoring is done
according to part 75.
§ 60.14
Modification
Yes (steam generating units
and IGCC facilities)
No (stationary combustion turbines)
§ 60.15
Reconstruction
Yes
§ 60.16
Priority list
No
§ 60.17
Incorporations by
reference
Yes
§ 60.18
General control device
requirements
No
§ 60.19
General notification and
reporting requirements
Yes
Does not apply to
notifications under § 75.61 or to information reported through
ECMPS.
Appendix A-1 to Part 60 - Test Methods 1 through 2F
40:9.0.1.1.1.0.1.1.1 : Appendix A
Appendix A-1 to Part 60 - Test Methods 1 through 2F Method 1 -
Sample and velocity traverses for stationary sources Method 1A -
Sample and velocity traverses for stationary sources with small
stacks or ducts Method 2 - Determination of stack gas velocity and
volumetric flow rate (Type S pitot tube) Method 2A - Direct
measurement of gas volume through pipes and small ducts Method 2B -
Determination of exhaust gas volume flow rate from gasoline vapor
incinerators Method 2C - Determination of gas velocity and
volumetric flow rate in small stacks or ducts (standard pitot tube)
Method 2D - Measurement of gas volume flow rates in small pipes and
ducts Method 2E - Determination of landfill gas production flow
rate Method 2F - Determination of Stack Gas Velocity and Volumetric
Flow Rate With Three-Dimensional Probes
The test methods in this appendix are referred to in § 60.8
(Performance Tests) and § 60.11 (Compliance With Standards and
Maintenance Requirements) of 40 CFR part 60, subpart A (General
Provisions). Specific uses of these test methods are described in
the standards of performance contained in the subparts, beginning
with Subpart D.
Within each standard of performance, a section title “Test
Methods and Procedures” is provided to: (1) Identify the test
methods to be used as reference methods to the facility subject to
the respective standard and (2) identify any special instructions
or conditions to be followed when applying a method to the
respective facility. Such instructions (for example, establish
sampling rates, volumes, or temperatures) are to be used either in
addition to, or as a substitute for procedures in a test method.
Similarly, for sources subject to emission monitoring requirements,
specific instructions pertaining to any use of a test method as a
reference method are provided in the subpart or in appendix B.
Inclusion of methods in this appendix is not intended as an
endorsement or denial of their applicability to sources that are
not subject to standards of performance. The methods are
potentially applicable to other sources; however, applicability
should be confirmed by careful and appropriate evaluation of the
conditions prevalent at such sources.
The approach followed in the formulation of the test methods
involves specifications for equipment, procedures, and performance.
In concept, a performance specification approach would be
preferable in all methods because this allows the greatest
flexibility to the user. In practice, however, this approach is
impractical in most cases because performance specifications cannot
be established. Most of the methods described herein, therefore,
involve specific equipment specifications and procedures, and only
a few methods in this appendix rely on performance criteria.
Minor changes in the test methods should not necessarily affect
the validity of the results and it is recognized that alternative
and equivalent methods exist. section 60.8 provides authority for
the Administrator to specify or approve (1) equivalent methods, (2)
alternative methods, and (3) minor changes in the methodology of
the test methods. It should be clearly understood that unless
otherwise identified all such methods and changes must have prior
approval of the Administrator. An owner employing such methods or
deviations from the test methods without obtaining prior approval
does so at the risk of subsequent disapproval and retesting with
approved methods.
Within the test methods, certain specific equipment or
procedures are recognized as being acceptable or potentially
acceptable and are specifically identified in the methods. The
items identified as acceptable options may be used without approval
but must be identified in the test report. The potentially
approvable options are cited as “subject to the approval of the
Administrator” or as “or equivalent.” Such potentially approvable
techniques or alternatives may be used at the discretion of the
owner without prior approval. However, detailed descriptions for
applying these potentially approvable techniques or alternatives
are not provided in the test methods. Also, the potentially
approvable options are not necessarily acceptable in all
applications. Therefore, an owner electing to use such potentially
approvable techniques or alternatives is responsible for: (1)
assuring that the techniques or alternatives are in fact applicable
and are properly executed; (2) including a written description of
the alternative method in the test report (the written method must
be clear and must be capable of being performed without additional
instruction, and the degree of detail should be similar to the
detail contained in the test methods); and (3) providing any
rationale or supporting data necessary to show the validity of the
alternative in the particular application. Failure to meet these
requirements can result in the Administrator's disapproval of the
alternative.
Method 1 - Sample and Velocity Traverses for Stationary Sources
Note:
This method does not include all of the specifications (e.g.,
equipment and supplies) and procedures (e.g., sampling) essential
to its performance. Some material is incorporated by reference from
other methods in this part. Therefore, to obtain reliable results,
persons using this method should have a thorough knowledge of at
least the following additional test method: Method 2.
1.0 Scope and Application
1.1 Measured Parameters. The purpose of the method is to provide
guidance for the selection of sampling ports and traverse points at
which sampling for air pollutants will be performed pursuant to
regulations set forth in this part. Two procedures are presented: a
simplified procedure, and an alternative procedure (see section
11.5). The magnitude of cyclonic flow of effluent gas in a stack or
duct is the only parameter quantitatively measured in the
simplified procedure.
1.2 Applicability. This method is applicable to gas streams
flowing in ducts, stacks, and flues. This method cannot be used
when: (1) the flow is cyclonic or swirling; or (2) a stack is
smaller than 0.30 meter (12 in.) in diameter, or 0.071 m 2 (113 in.
2) in cross-sectional area. The simplified procedure cannot be used
when the measurement site is less than two stack or duct diameters
downstream or less than a half diameter upstream from a flow
disturbance.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
Note:
The requirements of this method must be considered before
construction of a new facility from which emissions are to be
measured; failure to do so may require subsequent alterations to
the stack or deviation from the standard procedure. Cases involving
variants are subject to approval by the Administrator.
2.0 Summary of Method
2.1 This method is designed to aid in the representative
measurement of pollutant emissions and/or total volumetric flow
rate from a stationary source. A measurement site where the
effluent stream is flowing in a known direction is selected, and
the cross-section of the stack is divided into a number of equal
areas. Traverse points are then located within each of these equal
areas.
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies.
6.1 Apparatus. The apparatus described below is required only
when utilizing the alternative site selection procedure described
in section 11.5 of this method.
6.1.1 Directional Probe. Any directional probe, such as United
Sensor Type DA Three-Dimensional Directional Probe, capable of
measuring both the pitch and yaw angles of gas flows is acceptable.
Before using the probe, assign an identification number to the
directional probe, and permanently mark or engrave the number on
the body of the probe. The pressure holes of directional probes are
susceptible to plugging when used in particulate-laden gas streams.
Therefore, a procedure for cleaning the pressure holes by
“back-purging” with pressurized air is required.
6.1.2 Differential Pressure Gauges. Inclined manometers, U-tube
manometers, or other differential pressure gauges (e.g.,
magnehelic gauges) that meet the specifications described in Method
2, section 6.2.
Note:
If the differential pressure gauge produces both negative and
positive readings, then both negative and positive pressure
readings shall be calibrated at a minimum of three points as
specified in Method 2, section 6.2.
7.0 Reagents and Standards [Reserved] 8.0 Sample Collection,
Preservation, Storage, and Transport [Reserved] 9.0 Quality Control
[Reserved] 10.0 Calibration and Standardization [Reserved] 11.0
Procedure
11.1 Selection of Measurement Site.
11.1.1 Sampling and/or velocity measurements are performed at a
site located at least eight stack or duct diameters downstream and
two diameters upstream from any flow disturbance such as a bend,
expansion, or contraction in the stack, or from a visible flame. If
necessary, an alternative location may be selected, at a position
at least two stack or duct diameters downstream and a half diameter
upstream from any flow disturbance.
11.1.2 An alternative procedure is available for determining the
acceptability of a measurement location not meeting the criteria
above. This procedure described in section 11.5 allows for the
determination of gas flow angles at the sampling points and
comparison of the measured results with acceptability criteria.
11.2 Determining the Number of Traverse Points.
11.2.1 Particulate Traverses.
11.2.1.1 When the eight- and two-diameter criterion can be met,
the minimum number of traverse points shall be: (1) twelve, for
circular or rectangular stacks with diameters (or equivalent
diameters) greater than 0.61 meter (24 in.); (2) eight, for
circular stacks with diameters between 0.30 and 0.61 meter (12 and
24 in.); and (3) nine, for rectangular stacks with equivalent
diameters between 0.30 and 0.61 meter (12 and 24 in.).
11.2.1.2 When the eight- and two-diameter criterion cannot be
met, the minimum number of traverse points is determined from
Figure 1-1. Before referring to the figure, however, determine the
distances from the measurement site to the nearest upstream and
downstream disturbances, and divide each distance by the stack
diameter or equivalent diameter, to determine the distance in terms
of the number of duct diameters. Then, determine from Figure 1-1
the minimum number of traverse points that corresponds:
(1) To the number of duct diameters upstream; and
(2) To the number of diameters downstream. Select the higher of
the two minimum numbers of traverse points, or a greater value, so
that for circular stacks, the number is a multiple of 4, and for
rectangular stacks, the number is one of those shown in Table
1-1.
11.2.2 Velocity (Non-Particulate) Traverses. When velocity or
volumetric flow rate is to be determined (but not particulate
matter), the same procedure as that used for particulate traverses
(Section 11.2.1) is followed, except that Figure 1-2 may be used
instead of Figure 1-1.
11.3 Cross-Sectional Layout and Location of Traverse Points.
11.3.1 Circular Stacks.
11.3.1.1 Locate the traverse points on two perpendicular
diameters according to Table 1-2 and the example shown in Figure
1-3. Any equation (see examples in References 2 and 3 in section
16.0) that gives the same values as those in Table 1-2 may be used
in lieu of Table 1-2.
11.3.1.2 For particulate traverses, one of the diameters must
coincide with the plane containing the greatest expected
concentration variation (e.g., after bends); one diameter
shall be congruent to the direction of the bend. This requirement
becomes less critical as the distance from the disturbance
increases; therefore, other diameter locations may be used, subject
to the approval of the Administrator.
11.3.1.3 In addition, for elliptical stacks having unequal
perpendicular diameters, separate traverse points shall be
calculated and located along each diameter. To determine the
cross-sectional area of the elliptical stack, use the following
equation:
11.3.1.4 In addition, for stacks having diameters greater than
0.61 m (24 in.), no traverse points shall be within 2.5 centimeters
(1.00 in.) of the stack walls; and for stack diameters equal to or
less than 0.61 m (24 in.), no traverse points shall be located
within 1.3 cm (0.50 in.) of the stack walls. To meet these
criteria, observe the procedures given below.
11.3.2 Stacks With Diameters Greater Than 0.61 m (24 in.).
11.3.2.1 When any of the traverse points as located in section
11.3.1 fall within 2.5 cm (1.0 in.) of the stack walls, relocate
them away from the stack walls to: (1) a distance of 2.5 cm (1.0
in.); or (2) a distance equal to the nozzle inside diameter,
whichever is larger. These relocated traverse points (on each end
of a diameter) shall be the “adjusted” traverse points.
11.3.2.2 Whenever two successive traverse points are combined to
form a single adjusted traverse point, treat the adjusted point as
two separate traverse points, both in the sampling and/or velocity
measurement procedure, and in recording of the data.
11.3.3 Stacks With Diameters Equal To or Less Than 0.61 m (24
in.). Follow the procedure in section 11.3.1.1, noting only that
any “adjusted” points should be relocated away from the stack walls
to: (1) a distance of 1.3 cm (0.50 in.); or (2) a distance equal to
the nozzle inside diameter, whichever is larger.
11.3.4 Rectangular Stacks.
11.3.4.1 Determine the number of traverse points as explained in
sections 11.1 and 11.2 of this method. From Table 1-1, determine
the grid configuration. Divide the stack cross-section into as many
equal rectangular elemental areas as traverse points, and then
locate a traverse point at the centroid of each equal area
according to the example in Figure 1-4.
11.3.4.2 To use more than the minimum number of traverse points,
expand the “minimum number of traverse points” matrix (see Table
1-1) by adding the extra traverse points along one or the other or
both legs of the matrix; the final matrix need not be balanced. For
example, if a 4 × 3 “minimum number of points” matrix were expanded
to 36 points, the final matrix could be 9 × 4 or 12 × 3, and would
not necessarily have to be 6 × 6. After constructing the final
matrix, divide the stack cross-section into as many equal
rectangular, elemental areas as traverse points, and locate a
traverse point at the centroid of each equal area.
11.3.4.3 The situation of traverse points being too close to the
stack walls is not expected to arise with rectangular stacks. If
this problem should ever arise, the Administrator must be contacted
for resolution of the matter.
11.4 Verification of Absence of Cyclonic Flow.
11.4.1 In most stationary sources, the direction of stack gas
flow is essentially parallel to the stack walls. However, cyclonic
flow may exist (1) after such devices as cyclones and inertial
demisters following venturi scrubbers, or (2) in stacks having
tangential inlets or other duct configurations which tend to induce
swirling; in these instances, the presence or absence of cyclonic
flow at the sampling location must be determined. The following
techniques are acceptable for this determination.
11.4.2 Level and zero the manometer. Connect a Type S pitot tube
to the manometer and leak-check system. Position the Type S pitot
tube at each traverse point, in succession, so that the planes of
the face openings of the pitot tube are perpendicular to the stack
cross-sectional plane; when the Type S pitot tube is in this
position, it is at “0° reference.” Note the differential pressure
(Δp) reading at each traverse point. If a null (zero) pitot reading
is obtained at 0° reference at a given traverse point, an
acceptable flow condition exists at that point. If the pitot
reading is not zero at 0° reference, rotate the pitot tube (up to
±90° yaw angle), until a null reading is obtained. Carefully
determine and record the value of the rotation angle (α) to the
nearest degree. After the null technique has been applied at each
traverse point, calculate the average of the absolute values of α;
assign α values of 0° to those points for which no rotation was
required, and include these in the overall average. If the average
value of α is greater than 20°, the overall flow condition in the
stack is unacceptable, and alternative methodology, subject to the
approval of the Administrator, must be used to perform accurate
sample and velocity traverses.
11.5 The alternative site selection procedure may be used to
determine the rotation angles in lieu of the procedure outlined in
section 11.4.
11.5.1 Alternative Measurement Site Selection Procedure. This
alternative applies to sources where measurement locations are less
than 2 equivalent or duct diameters downstream or less than
one-half duct diameter upstream from a flow disturbance. The
alternative should be limited to ducts larger than 24 in. in
diameter where blockage and wall effects are minimal. A directional
flow-sensing probe is used to measure pitch and yaw angles of the
gas flow at 40 or more traverse points; the resultant angle is
calculated and compared with acceptable criteria for mean and
standard deviation.
Note:
Both the pitch and yaw angles are measured from a line passing
through the traverse point and parallel to the stack axis. The
pitch angle is the angle of the gas flow component in the plane
that INCLUDES the traverse line and is parallel to the stack axis.
The yaw angle is the angle of the gas flow component in the plane
PERPENDICULAR to the traverse line at the traverse point and is
measured from the line passing through the traverse point and
parallel to the stack axis.
11.5.2 Traverse Points. Use a minimum of 40 traverse points for
circular ducts and 42 points for rectangular ducts for the gas flow
angle determinations. Follow the procedure outlined in section 11.3
and Table 1-1 or 1-2 for the location and layout of the traverse
points. If the measurement location is determined to be acceptable
according to the criteria in this alternative procedure, use the
same traverse point number and locations for sampling and velocity
measurements.
11.5.3 Measurement Procedure.
11.5.3.1 Prepare the directional probe and differential pressure
gauges as recommended by the manufacturer. Capillary tubing or
surge tanks may be used to dampen pressure fluctuations. It is
recommended, but not required, that a pretest leak check be
conducted. To perform a leak check, pressurize or use suction on
the impact opening until a reading of at least 7.6 cm (3 in.) H2O
registers on the differential pressure gauge, then plug the impact
opening. The pressure of a leak-free system will remain stable for
at least 15 seconds.
11.5.3.2 Level and zero the manometers. Since the manometer
level and zero may drift because of vibrations and temperature
changes, periodically check the level and zero during the
traverse.
11.5.3.3 Position the probe at the appropriate locations in the
gas stream, and rotate until zero deflection is indicated for the
yaw angle pressure gauge. Determine and record the yaw angle.
Record the pressure gauge readings for the pitch angle, and
determine the pitch angle from the calibration curve. Repeat this
procedure for each traverse point. Complete a “back-purge” of the
pressure lines and the impact openings prior to measurements of
each traverse point.
11.5.3.4 A post-test check as described in section 11.5.3.1 is
required. If the criteria for a leak-free system are not met,
repair the equipment, and repeat the flow angle measurements.
11.5.4 Calibration. Use a flow system as described in sections
10.1.2.1 and 10.1.2.2 of Method 2. In addition, the flow system
shall have the capacity to generate two test-section velocities:
one between 365 and 730 m/min (1,200 and 2,400 ft/min) and one
between 730 and 1,100 m/min (2,400 and 3,600 ft/min).
11.5.4.1 Cut two entry ports in the test section. The axes
through the entry ports shall be perpendicular to each other and
intersect in the centroid of the test section. The ports should be
elongated slots parallel to the axis of the test section and of
sufficient length to allow measurement of pitch angles while
maintaining the pitot head position at the test-section centroid.
To facilitate alignment of the directional probe during
calibration, the test section should be constructed of plexiglass
or some other transparent material. All calibration measurements
should be made at the same point in the test section, preferably at
the centroid of the test section.
11.5.4.2 To ensure that the gas flow is parallel to the central
axis of the test section, follow the procedure outlined in section
11.4 for cyclonic flow determination to measure the gas flow angles
at the centroid of the test section from two test ports located 90°
apart. The gas flow angle measured in each port must be ±2° of 0°.
Straightening vanes should be installed, if necessary, to meet this
criterion.
11.5.4.3 Pitch Angle Calibration. Perform a calibration traverse
according to the manufacturer's recommended protocol in 5°
increments for angles from −60° to + 60° at one velocity in each of
the two ranges specified above. Average the pressure ratio values
obtained for each angle in the two flow ranges, and plot a
calibration curve with the average values of the pressure ratio (or
other suitable measurement factor as recommended by the
manufacturer) versus the pitch angle. Draw a smooth line through
the data points. Plot also the data values for each traverse point.
Determine the differences between the measured data values and the
angle from the calibration curve at the same pressure ratio. The
difference at each comparison must be within 2° for angles between
0° and 40° and within 3° for angles between 40° and 60°.
11.5.4.4 Yaw Angle Calibration. Mark the three-dimensional probe
to allow the determination of the yaw position of the probe. This
is usually a line extending the length of the probe and aligned
with the impact opening. To determine the accuracy of measurements
of the yaw angle, only the zero or null position need be calibrated
as follows: Place the directional probe in the test section, and
rotate the probe until the zero position is found. With a
protractor or other angle measuring device, measure the angle
indicated by the yaw angle indicator on the three-dimensional
probe. This should be within 2° of 0°. Repeat this measurement for
any other points along the length of the pitot where yaw angle
measurements could be read in order to account for variations in
the pitot markings used to indicate pitot head positions.
12.0 Data Analysis and Calculations
12.1 Nomenclature.
L = length. n = total number of traverse points. Pi = pitch angle
at traverse point i, degree. Ravg = average resultant angle,
degree. Ri = resultant angle at traverse point i, degree. Sd =
standard deviation, degree. W = width. Yi = yaw angle at traverse
point i, degree.
12.2 For a rectangular cross section, an equivalent diameter
(De) shall be calculated using the following equation, to determine
the upstream and downstream distances:
12.3 If use of the alternative site selection procedure (Section
11.5 of this method) is required, perform the following
calculations using the equations below: the resultant angle at each
traverse point, the average resultant angle, and the standard
deviation. Complete the calculations retaining at least one extra
significant figure beyond that of the acquired data. Round the
values after the final calculations.
12.3.1 Calculate the resultant angle at each traverse point:
12.3.2 Calculate the average resultant for the measurements:
12.3.3 Calculate the standard deviations:
12.3.4 Acceptability Criteria. The measurement location is
acceptable if Ravg ≤20° and Sd ≤10°.
1. Determining Dust Concentration in a Gas Stream, ASME
Performance Test Code No. 27. New York. 1957.
2. DeVorkin, Howard, et al. Air Pollution Source Testing Manual.
Air Pollution Control District. Los Angeles, CA. November 1963.
3. Methods for Determining of Velocity, Volume, Dust and Mist
Content of Gases. Western Precipitation Division of Joy
Manufacturing Co. Los Angeles, CA. Bulletin WP-50. 1968.
4. Standard Method for Sampling Stacks for Particulate Matter.
In: 1971 Book of ASTM Standards, Part 23. ASTM Designation D
2928-71. Philadelphia, PA. 1971.
5. Hanson, H.A., et al. Particulate Sampling Strategies for
Large Power Plants Including Nonuniform Flow. USEPA, ORD, ESRL,
Research Triangle Park, NC. EPA-600/2-76-170. June 1976.
6. Entropy Environmentalists, Inc. Determination of the Optimum
Number of Sampling Points: An Analysis of Method 1 Criteria.
Environmental Protection Agency. Research Triangle Park, NC. EPA
Contract No. 68-01-3172, Task 7.
7. Hanson, H.A., R.J. Davini, J.K. Morgan, and A.A. Iversen.
Particulate Sampling Strategies for Large Power Plants Including
Nonuniform Flow. USEPA, Research Triangle Park, NC. Publication No.
EPA-600/2-76-170. June 1976. 350 pp.
8. Brooks, E.F., and R.L. Williams. Flow and Gas Sampling
Manual. U.S. Environmental Protection Agency. Research Triangle
Park, NC. Publication No. EPA-600/2-76-203. July 1976. 93 pp.
9. Entropy Environmentalists, Inc. Traverse Point Study. EPA
Contract No. 68-02-3172. June 1977. 19 pp.
10. Brown, J. and K. Yu. Test Report: Particulate Sampling
Strategy in Circular Ducts. Emission Measurement Branch. U.S.
Environmental Protection Agency, Research Triangle Park, NC 27711.
July 31, 1980. 12 pp.
11. Hawksley, P.G.W., S. Badzioch, and J.H. Blackett.
Measurement of Solids in Flue Gases. Leatherhead, England, The
British Coal Utilisation Research Association. 1961. pp.
129-133.
12. Knapp, K.T. The Number of Sampling Points Needed for
Representative Source Sampling. In: Proceedings of the Fourth
National Conference on Energy and Environment. Theodore, L. et al.
(ed). Dayton, Dayton section of the American Institute of Chemical
Engineers. October 3-7, 1976. pp. 563-568.
13. Smith, W.S. and D.J. Grove. A Proposed Extension of EPA
Method 1 Criteria. Pollution Engineering. XV (8):36-37. August
1983.
14. Gerhart, P.M. and M.J. Dorsey. Investigation of Field Test
Procedures for Large Fans. University of Akron. Akron, OH. (EPRI
Contract CS-1651). Final Report (RP-1649-5). December 1980.
15. Smith, W.S. and D.J. Grove. A New Look at Isokinetic
Sampling - Theory and Applications. Source Evaluation Society
Newsletter. VIII (3):19-24. August 1983.
17.0 Tables, Diagrams, Flowcharts, and Validation Data
Table 1-1 Cross-Section Layout for
Rectangular Stacks
Number of tranverse points
layout
Matrix
9
3 × 3
12
4 × 3
16
4 × 4
20
5 × 4
25
5 × 5
30
6 × 5
36
6 × 6
42
7 × 6
49
7 × 7
Table 1-2 - Location of Traverse Points in
Circular Stacks
[Percent of stack diameter from
inside wall to tranverse point]
Traverse
point
number on
a diameter
Number of
traverse points on a diameter
2
4
6
8
10
12
14
16
18
20
22
24
1
14.6
6.7
4.4
3.2
2.6
2.1
1.8
1.6
1.4
1.3
1.1
1.1
2
85.4
25.0
14.6
10.5
8.2
6.7
5.7
4.9
4.4
3.9
3.5
3.2
3
75.0
29.6
19.4
14.6
11.8
9.9
8.5
7.5
6.7
6.0
5.5
4
93.3
70.4
32.3
22.6
17.7
14.6
12.5
10.9
9.7
8.7
7.9
5
85.4
67.7
34.2
25.0
20.1
16.9
14.6
12.9
11.6
10.5
6
95.6
80.6
65.8
35.6
26.9
22.0
18.8
16.5
14.6
13.2
7
89.5
77.4
64.4
36.6
28.3
23.6
20.4
18.0
16.1
8
96.8
85.4
75.0
63.4
37.5
29.6
25.0
21.8
19.4
9
91.8
82.3
73.1
62.5
38.2
30.6
26.2
23.0
10
97.4
88.2
79.9
71.7
61.8
38.8
31.5
27.2
11
93.3
85.4
78.0
70.4
61.2
39.3
32.3
12
97.9
90.1
83.1
76.4
69.4
60.7
39.8
13
94.3
87.5
81.2
75.0
68.5
60.2
14
98.2
91.5
85.4
79.6
73.8
67.7
15
95.1
89.1
83.5
78.2
72.8
16
98.4
92.5
87.1
82.0
77.0
17
95.6
90.3
85.4
80.6
18
98.6
93.3
88.4
83.9
19
96.1
91.3
86.8
20
98.7
94.0
89.5
21
96.5
92.1
22
98.9
94.5
23
96.8
24
99.9
Method 1A
- Sample and Velocity Traverses for Stationary Sources With Small
Stacks or Ducts Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling) essential to its performance. Some material is
incorporated by reference from other methods in this part.
Therefore, to obtain reliable results, persons using this method
should have a thorough knowledge of at least the following
additional test method: Method 1.
1.0 Scope and Application
1.1 Measured Parameters. The purpose of the method is to provide
guidance for the selection of sampling ports and traverse points at
which sampling for air pollutants will be performed pursuant to
regulations set forth in this part.
1.2 Applicability. The applicability and principle of this
method are identical to Method 1, except its applicability is
limited to stacks or ducts. This method is applicable to flowing
gas streams in ducts, stacks, and flues of less than about 0.30
meter (12 in.) in diameter, or 0.071 m 2 (113 in. 2) in
cross-sectional area, but equal to or greater than about 0.10 meter
(4 in.) in diameter, or 0.0081 m 2 (12.57 in. 2) in cross-sectional
area. This method cannot be used when the flow is cyclonic or
swirling.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 The method is designed to aid in the representative
measurement of pollutant emissions and/or total volumetric flow
rate from a stationary source. A measurement site or a pair of
measurement sites where the effluent stream is flowing in a known
direction is (are) selected. The cross-section of the stack is
divided into a number of equal areas. Traverse points are then
located within each of these equal areas.
2.2 In these small diameter stacks or ducts, the conventional
Method 5 stack assembly (consisting of a Type S pitot tube attached
to a sampling probe, equipped with a nozzle and thermocouple)
blocks a significant portion of the cross-section of the duct and
causes inaccurate measurements. Therefore, for particulate matter
(PM) sampling in small stacks or ducts, the gas velocity is
measured using a standard pitot tube downstream of the actual
emission sampling site. The straight run of duct between the PM
sampling and velocity measurement sites allows the flow profile,
temporarily disturbed by the presence of the sampling probe, to
redevelop and stabilize.
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies [Reserved] 7.0 Reagents and Standards
[Reserved] 8.0 Sample Collection, Preservation, Storage, and
Transport [Reserved] 9.0 Quality Control [Reserved] 10.0
Calibration and Standardization [Reserved] 11.0 Procedure
11.1 Selection of Measurement Site.
11.1.1 Particulate Measurements - Steady or Unsteady Flow.
Select a particulate measurement site located preferably at least
eight equivalent stack or duct diameters downstream and 10
equivalent diameters upstream from any flow disturbances such as
bends, expansions, or contractions in the stack, or from a visible
flame. Next, locate the velocity measurement site eight equivalent
diameters downstream of the particulate measurement site (see
Figure 1A-1). If such locations are not available, select an
alternative particulate measurement location at least two
equivalent stack or duct diameters downstream and two and one-half
diameters upstream from any flow disturbance. Then, locate the
velocity measurement site two equivalent diameters downstream from
the particulate measurement site. (See section 12.2 of Method 1 for
calculating equivalent diameters for a rectangular
cross-section.)
11.1.2 PM Sampling (Steady Flow) or Velocity (Steady or Unsteady
Flow) Measurements. For PM sampling when the volumetric flow rate
in a duct is constant with respect to time, section 11.1.1 of
Method 1 may be followed, with the PM sampling and velocity
measurement performed at one location. To demonstrate that the flow
rate is constant (within 10 percent) when PM measurements are made,
perform complete velocity traverses before and after the PM
sampling run, and calculate the deviation of the flow rate derived
after the PM sampling run from the one derived before the PM
sampling run. The PM sampling run is acceptable if the deviation
does not exceed 10 percent.
11.2 Determining the Number of Traverse Points.
11.2.1 Particulate Measurements (Steady or Unsteady Flow). Use
Figure 1-1 of Method 1 to determine the number of traverse points
to use at both the velocity measurement and PM sampling locations.
Before referring to the figure, however, determine the distances
between both the velocity measurement and PM sampling sites to the
nearest upstream and downstream disturbances. Then divide each
distance by the stack diameter or equivalent diameter to express
the distances in terms of the number of duct diameters. Then,
determine the number of traverse points from Figure 1-1 of Method 1
corresponding to each of these four distances. Choose the highest
of the four numbers of traverse points (or a greater number) so
that, for circular ducts the number is a multiple of four; and for
rectangular ducts, the number is one of those shown in Table 1-1 of
Method 1. When the optimum duct diameter location criteria can be
satisfied, the minimum number of traverse points required is eight
for circular ducts and nine for rectangular ducts.
11.2.2 PM Sampling (Steady Flow) or only Velocity
(Non-Particulate) Measurements. Use Figure 1-2 of Method 1 to
determine number of traverse points, following the same procedure
used for PM sampling as described in section 11.2.1 of Method 1.
When the optimum duct diameter location criteria can be satisfied,
the minimum number of traverse points required is eight for
circular ducts and nine for rectangular ducts.
11.3 Cross-sectional Layout, Location of Traverse Points, and
Verification of the Absence of Cyclonic Flow. Same as Method 1,
sections 11.3 and 11.4, respectively.
12.0 Data Analysis and Calculations [Reserved] 13.0 Method
Performance [Reserved] 14.0 Pollution Prevention [Reserved] 15.0
Waste Management [Reserved] 16.0 References
Same as Method 1, section 16.0, References 1 through 6, with the
addition of the following:
1. Vollaro, Robert F. Recommended Procedure for Sample Traverses
in Ducts Smaller Than 12 Inches in Diameter. U.S. Environmental
Protection Agency, Emission Measurement Branch, Research Triangle
Park, North Carolina. January 1977.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 2 -
Determination of Stack Gas Velocity and Volumetric Flow Rate (Type
S Pitot Tube) Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling) essential to its performance. Some material is
incorporated by reference from other methods in this part.
Therefore, to obtain reliable results, persons using this method
should have a thorough knowledge of at least the following
additional test method: Method 1.
1.0 Scope and Application.
1.1 This method is applicable for the determination of the
average velocity and the volumetric flow rate of a gas stream.
1.2 This method is not applicable at measurement sites that fail
to meet the criteria of Method 1, section 11.1. Also, the method
cannot be used for direct measurement in cyclonic or swirling gas
streams; section 11.4 of Method 1 shows how to determine cyclonic
or swirling flow conditions. When unacceptable conditions exist,
alternative procedures, subject to the approval of the
Administrator, must be employed to produce accurate flow rate
determinations. Examples of such alternative procedures are: (1) to
install straightening vanes; (2) to calculate the total volumetric
flow rate stoichiometrically, or (3) to move to another measurement
site at which the flow is acceptable.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method.
2.1 The average gas velocity in a stack is determined from the
gas density and from measurement of the average velocity head with
a Type S (Stausscheibe or reverse type) pitot tube.
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies
Specifications for the apparatus are given below. Any other
apparatus that has been demonstrated (subject to approval of the
Administrator) to be capable of meeting the specifications will be
considered acceptable.
6.1 Type S Pitot Tube.
6.1.1 Pitot tube made of metal tubing (e.g., stainless
steel) as shown in Figure 2-1. It is recommended that the external
tubing diameter (dimension Dt, Figure 2-2b) be between 0.48 and
0.95 cm ( 3/16 and 3/8 inch). There shall be an equal distance from
the base of each leg of the pitot tube to its face-opening plane
(dimensions PA and PB, Figure 2-2b); it is recommended that this
distance be between 1.05 and 1.50 times the external tubing
diameter. The face openings of the pitot tube shall, preferably, be
aligned as shown in Figure 2-2; however, slight misalignments of
the openings are permissible (see Figure 2-3).
6.1.2 The Type S pitot tube shall have a known coefficient,
determined as outlined in section 10.0. An identification number
shall be assigned to the pitot tube; this number shall be
permanently marked or engraved on the body of the tube. A standard
pitot tube may be used instead of a Type S, provided that it meets
the specifications of sections 6.7 and 10.2. Note, however, that
the static and impact pressure holes of standard pitot tubes are
susceptible to plugging in particulate-laden gas streams.
Therefore, whenever a standard pitot tube is used to perform a
traverse, adequate proof must be furnished that the openings of the
pitot tube have not plugged up during the traverse period. This can
be accomplished by comparing the velocity head (Δp) measurement
recorded at a selected traverse point (readable Δp value) with a
second Δp measurement recorded after “back purging” with
pressurized air to clean the impact and static holes of the
standard pitot tube. If the before and after Δp measurements are
within 5 percent, then the traverse data are acceptable. Otherwise,
the data should be rejected and the traverse measurements redone.
Note that the selected traverse point should be one that
demonstrates a readable Δp value. If “back purging” at regular
intervals is part of a routine procedure, then comparative Δp
measurements shall be conducted as above for the last two traverse
points that exhibit suitable Δp measurements.
6.2 Differential Pressure Gauge. An inclined manometer or
equivalent device. Most sampling trains are equipped with a 10 in.
(water column) inclined-vertical manometer, having 0.01 in. H20
divisions on the 0 to 1 in. inclined scale, and 0.1 in. H20
divisions on the 1 to 10 in. vertical scale. This type of manometer
(or other gauge of equivalent sensitivity) is satisfactory for the
measurement of Δp values as low as 1.27 mm (0.05 in.) H20. However,
a differential pressure gauge of greater sensitivity shall be used
(subject to the approval of the Administrator), if any of the
following is found to be true: (1) the arithmetic average of all Δp
readings at the traverse points in the stack is less than 1.27 mm
(0.05 in.) H20; (2) for traverses of 12 or more points, more than
10 percent of the individual Δp readings are below 1.27 mm (0.05
in.) H20; or (3) for traverses of fewer than 12 points, more than
one Δp reading is below 1.27 mm (0.05 in.) H20. Reference 18 (see
section 17.0) describes commercially available instrumentation for
the measurement of low-range gas velocities.
6.2.1 As an alternative to criteria (1) through (3) above,
Equation 2-1 (Section 12.2) may be used to determine the necessity
of using a more sensitive differential pressure gauge. If T is
greater than 1.05, the velocity head data are unacceptable and a
more sensitive differential pressure gauge must be used.
Note:
If differential pressure gauges other than inclined manometers
are used (e.g., magnehelic gauges), their calibration must
be checked after each test series. To check the calibration of a
differential pressure gauge, compare Δp readings of the gauge with
those of a gauge-oil manometer at a minimum of three points,
approximately representing the range of Δp values in the stack. If,
at each point, the values of Δp as read by the differential
pressure gauge and gauge-oil manometer agree to within 5 percent,
the differential pressure gauge shall be considered to be in proper
calibration. Otherwise, the test series shall either be voided, or
procedures to adjust the measured Δp values and final results shall
be used, subject to the approval of the Administrator.
6.3 Temperature Sensor. A thermocouple, liquid-filled bulb
thermometer, bimetallic thermometer, mercury-in-glass thermometer,
or other gauge capable of measuring temperatures to within 1.5
percent of the minimum absolute stack temperature. The temperature
sensor shall be attached to the pitot tube such that the sensor tip
does not touch any metal; the gauge shall be in an
interference-free arrangement with respect to the pitot tube face
openings (see Figure 2-1 and Figure 2-4). Alternative positions may
be used if the pitot tube-temperature gauge system is calibrated
according to the procedure of section 10.0. Provided that a
difference of not more than 1 percent in the average velocity
measurement is introduced, the temperature gauge need not be
attached to the pitot tube. This alternative is subject to the
approval of the Administrator.
6.4 Pressure Probe and Gauge. A piezometer tube and mercury- or
water-filled U-tube manometer capable of measuring stack pressure
to within 2.5 mm (0.1 in.) Hg. The static tap of a standard type
pitot tube or one leg of a Type S pitot tube with the face opening
planes positioned parallel to the gas flow may also be used as the
pressure probe.
6.5 Barometer. A mercury, aneroid, or other barometer capable of
measuring atmospheric pressure to within 2.54 mm (0.1 in.) Hg.
Note:
The barometric pressure reading may be obtained from a nearby
National Weather Service station. In this case, the station value
(which is the absolute barometric pressure) shall be requested and
an adjustment for elevation differences between the weather station
and sampling point shall be made at a rate of minus 2.5 mm (0.1
in.) Hg per 30 m (100 ft) elevation increase or plus 2.5 mm (0.1
in.) Hg per 30 m (100 ft.) for elevation decrease.
6.6 Gas Density Determination Equipment. Method 3 equipment, if
needed (see section 8.6), to determine the stack gas dry molecular
weight, and Method 4 (reference method) or Method 5 equipment for
moisture content determination. Other methods may be used subject
to approval of the Administrator.
6.7 Calibration Pitot Tube. Calibration of the Type S pitot tube
requires a standard pitot tube for a reference. When calibration of
the Type S pitot tube is necessary (see Section 10.1), a standard
pitot tube shall be used for a reference. The standard pitot tube
shall, preferably, have a known coefficient, obtained directly from
the National Institute of Standards and Technology (NIST),
Gaithersburg, MD 20899, (301) 975-2002; or by calibration against
another standard pitot tube with a NIST-traceable coefficient.
Alternatively, a standard pitot tube designed according to the
criteria given in sections 6.7.1 through 6.7.5 below and
illustrated in Figure 2-5 (see also References 7, 8, and 17 in
section 17.0) may be used. Pitot tubes designed according to these
specifications will have baseline coefficients of 0.99 ±0.01.
6.7.1 Standard Pitot Design.
6.7.1.1 Hemispherical (shown in Figure 2-5), ellipsoidal, or
conical tip.
6.7.1.2 A minimum of six diameters straight run (based upon D,
the external diameter of the tube) between the tip and the static
pressure holes.
6.7.1.3 A minimum of eight diameters straight run between the
static pressure holes and the centerline of the external tube,
following the 90° bend.
6.7.1.4 Static pressure holes of equal size (approximately 0.1
D), equally spaced in a piezometer ring configuration.
6.7.1.5 90° bend, with curved or mitered junction.
6.8 Differential Pressure Gauge for Type S Pitot Tube
Calibration. An inclined manometer or equivalent. If the
single-velocity calibration technique is employed (see section
10.1.2.3), the calibration differential pressure gauge shall be
readable to the nearest 0.127 mm (0.005 in.) H20. For multivelocity
calibrations, the gauge shall be readable to the nearest 0.127 mm
(0.005 in.) H20 for Δp values between 1.27 and 25.4 mm (0.05 and
1.00 in.) H20, and to the nearest 1.27 mm (0.05 in.) H20 for Δp
values above 25.4 mm (1.00 in.) H20. A special, more sensitive
gauge will be required to read Δp values below 1.27 mm (0.05 in.)
H20 (see Reference 18 in section 16.0).
7.0 Reagents and Standards [Reserved] 8.0 Sample Collection and
Analysis
8.1 Set up the apparatus as shown in Figure 2-1. Capillary
tubing or surge tanks installed between the manometer and pitot
tube may be used to dampen ΔP fluctuations. It is recommended, but
not required, that a pretest leak-check be conducted as follows:
(1) blow through the pitot impact opening until at least 7.6 cm
(3.0 in.) H2O velocity head registers on the manometer; then, close
off the impact opening. The pressure shall remain stable (±2.5 mm
H2O, ±0.10 in. H2O) for at least 15 seconds; (2) do the same for
the static pressure side, except using suction to obtain the
minimum of 7.6 cm (3.0 in.) H2O. Other leak-check procedures,
subject to the approval of the Administrator, may be used.
8.2 Level and zero the manometer. Because the manometer level
and zero may drift due to vibrations and temperature changes, make
periodic checks during the traverse (at least once per hour).
Record all necessary data on a form similar to that shown in Figure
2-6.
8.3 Measure the velocity head and temperature at the traverse
points specified by Method 1. Ensure that the proper differential
pressure gauge is being used for the range of Δp values encountered
(see section 6.2). If it is necessary to change to a more sensitive
gauge, do so, and remeasure the Δp and temperature readings at each
traverse point. Conduct a post-test leak-check (mandatory), as
described in section 8.1 above, to validate the traverse run.
8.4 Measure the static pressure in the stack. One reading is
usually adequate.
8.5 Determine the atmospheric pressure.
8.6 Determine the stack gas dry molecular weight. For combustion
processes or processes that emit essentially CO2, O2, CO, and N2,
use Method 3. For processes emitting essentially air, an analysis
need not be conducted; use a dry molecular weight of 29.0. For
other processes, other methods, subject to the approval of the
Administrator, must be used.
8.7 Obtain the moisture content from Method 4 (reference method,
or equivalent) or from Method 5.
8.8 Determine the cross-sectional area of the stack or duct at
the sampling location. Whenever possible, physically measure the
stack dimensions rather than using blueprints. Do not assume that
stack diameters are equal. Measure each diameter distance to verify
its dimensions.
9.0 Quality Control
Section
Quality control measure
Effect
10.1-10.4
Sampling equipment
calibration
Ensure accurate measurement of
stack gas flow rate, sample volume.
10.0 Calibration and Standardization
10.1 Type S Pitot Tube. Before its initial use, carefully
examine the Type S pitot tube top, side, and end views to verify
that the face openings of the tube are aligned within the
specifications illustrated in Figures 2-2 and 2-3. The pitot tube
shall not be used if it fails to meet these alignment
specifications. After verifying the face opening alignment, measure
and record the following dimensions of the pitot tube: (a) the
external tubing diameter (dimension Dt, Figure 2-2b); and (b) the
base-to-opening plane distances (dimensions PA and PB, Figure
2-2b). If Dt is between 0.48 and 0.95 cm 3/16 and 3/8 in.), and if
PA and PB are equal and between 1.05 and 1.50 Dt, there are two
possible options: (1) the pitot tube may be calibrated according to
the procedure outlined in sections 10.1.2 through 10.1.5, or (2) a
baseline (isolated tube) coefficient value of 0.84 may be assigned
to the pitot tube. Note, however, that if the pitot tube is part of
an assembly, calibration may still be required, despite knowledge
of the baseline coefficient value (see section 10.1.1). If Dt, PA,
and PB are outside the specified limits, the pitot tube must be
calibrated as outlined in sections 10.1.2 through 10.1.5.
10.1.1 Type S Pitot Tube Assemblies. During sample and velocity
traverses, the isolated Type S pitot tube is not always used; in
many instances, the pitot tube is used in combination with other
source-sampling components (e.g., thermocouple, sampling probe,
nozzle) as part of an “assembly.” The presence of other sampling
components can sometimes affect the baseline value of the Type S
pitot tube coefficient (Reference 9 in section 17.0); therefore, an
assigned (or otherwise known) baseline coefficient value may or may
not be valid for a given assembly. The baseline and assembly
coefficient values will be identical only when the relative
placement of the components in the assembly is such that
aerodynamic interference effects are eliminated. Figures 2-4, 2-7,
and 2-8 illustrate interference-free component arrangements for
Type S pitot tubes having external tubing diameters between 0.48
and 0.95 cm ( 3/16 and 3/8 in.). Type S pitot tube assemblies that
fail to meet any or all of the specifications of Figures 2-4, 2-7,
and 2-8 shall be calibrated according to the procedure outlined in
sections 10.1.2 through 10.1.5, and prior to calibration, the
values of the intercomponent spacings (pitot-nozzle,
pitot-thermocouple, pitot-probe sheath) shall be measured and
recorded.
Note:
Do not use a Type S pitot tube assembly that is constructed such
that the impact pressure opening plane of the pitot tube is below
the entry plane of the nozzle (see Figure 2-7B).
10.1.2 Calibration Setup. If the Type S pitot tube is to be
calibrated, one leg of the tube shall be permanently marked A, and
the other, B. Calibration shall be performed in a flow system
having the following essential design features:
10.1.2.1 The flowing gas stream must be confined to a duct of
definite cross-sectional area, either circular or rectangular. For
circular cross sections, the minimum duct diameter shall be 30.48
cm (12 in.); for rectangular cross sections, the width (shorter
side) shall be at least 25.4 cm (10 in.).
10.1.2.2 The cross-sectional area of the calibration duct must
be constant over a distance of 10 or more duct diameters. For a
rectangular cross section, use an equivalent diameter, calculated
according to Equation 2-2 (see section 12.3), to determine the
number of duct diameters. To ensure the presence of stable, fully
developed flow patterns at the calibration site, or “test section,”
the site must be located at least eight diameters downstream and
two diameters upstream from the nearest disturbances.
Note:
The eight- and two-diameter criteria are not absolute; other
test section locations may be used (subject to approval of the
Administrator), provided that the flow at the test site has been
demonstrated to be or found stable and parallel to the duct
axis.
10.1.2.3 The flow system shall have the capacity to generate a
test-section velocity around 910 m/min (3,000 ft/min). This
velocity must be constant with time to guarantee constant and
steady flow during the entire period of calibration. A centrifugal
fan is recommended for this purpose, as no flow rate adjustment for
back pressure of the fan is allowed during the calibration process.
Note that Type S pitot tube coefficients obtained by
single-velocity calibration at 910 m/min (3,000 ft/min) will
generally be valid to ±3 percent for the measurement of velocities
above 300 m/min (1,000 ft/min) and to ±6 percent for the
measurement of velocities between 180 and 300 m/min (600 and 1,000
ft/min). If a more precise correlation between the pitot tube
coefficient (Cp) and velocity is desired, the flow system should
have the capacity to generate at least four distinct,
time-invariant test-section velocities covering the velocity range
from 180 to 1,500 m/min (600 to 5,000 ft/min), and calibration data
shall be taken at regular velocity intervals over this range (see
References 9 and 14 in section 17.0 for details).
10.1.2.4 Two entry ports, one for each of the standard and Type
S pitot tubes, shall be cut in the test section. The standard pitot
entry port shall be located slightly downstream of the Type S port,
so that the standard and Type S impact openings will lie in the
same cross-sectional plane during calibration. To facilitate
alignment of the pitot tubes during calibration, it is advisable
that the test section be constructed of Plexiglas TM or some other
transparent material.
10.1.3 Calibration Procedure. Note that this procedure is a
general one and must not be used without first referring to the
special considerations presented in section 10.1.5. Note also that
this procedure applies only to single-velocity calibration. To
obtain calibration data for the A and B sides of the Type S pitot
tube, proceed as follows:
10.1.3.1 Make sure that the manometer is properly filled and
that the oil is free from contamination and is of the proper
density. Inspect and leak-check all pitot lines; repair or replace
if necessary.
10.1.3.2 Level and zero the manometer. Switch on the fan, and
allow the flow to stabilize. Seal the Type S pitot tube entry
port.
10.1.3.3 Ensure that the manometer is level and zeroed. Position
the standard pitot tube at the calibration point (determined as
outlined in section 10.1.5.1), and align the tube so that its tip
is pointed directly into the flow. Particular care should be taken
in aligning the tube to avoid yaw and pitch angles. Make sure that
the entry port surrounding the tube is properly sealed.
10.1.3.4 Read Δpstd, and record its value in a data table
similar to the one shown in Figure 2-9. Remove the standard pitot
tube from the duct, and disconnect it from the manometer. Seal the
standard entry port. Make no adjustment to the fan speed or other
wind tunnel volumetric flow control device between this reading and
the corresponding Type S pitot reading.
10.1.3.5 Connect the Type S pitot tube to the manometer and
leak-check. Open the Type S tube entry port. Check the manometer
level and zero. Insert and align the Type S pitot tube so that its
A side impact opening is at the same point as was the standard
pitot tube and is pointed directly into the flow. Make sure that
the entry port surrounding the tube is properly sealed.
10.1.3.6 Read Δps, and enter its value in the data table. Remove
the Type S pitot tube from the duct, and disconnect it from the
manometer.
10.1.3.7 Repeat Steps 10.1.3.3 through 10.1.3.6 until three
pairs of Δp readings have been obtained for the A side of the Type
S pitot tube, with all the paired observations conducted at a
constant fan speed (no changes to fan velocity between observed
readings).
10.1.3.8 Repeat Steps 10.1.3.3 through 10.1.3.7 for the B side
of the Type S pitot tube.
10.1.3.9 Perform calculations as described in section 12.4. Use
the Type S pitot tube only if the values of σA and σB are less than
or equal to 0.01 and if the absolute value of the difference
between C p(A) and C p(B) is 0.01 or less.
10.1.4 Special Considerations.
10.1.4.1 Selection of Calibration Point.
10.1.4.1.1 When an isolated Type S pitot tube is calibrated,
select a calibration point at or near the center of the duct, and
follow the procedures outlined in section 10.1.3. The Type S pitot
coefficients measured or calculated, (i.e., C p(A) and C
p(B)) will be valid, so long as either: (1) the isolated pitot tube
is used; or (2) the pitot tube is used with other components
(nozzle, thermocouple, sample probe) in an arrangement that is free
from aerodynamic interference effects (see Figures 2-4, 2-7, and
2-8).
10.1.4.1.2 For Type S pitot tube-thermocouple combinations
(without probe assembly), select a calibration point at or near the
center of the duct, and follow the procedures outlined in section
10.1.3. The coefficients so obtained will be valid so long as the
pitot tube-thermocouple combination is used by itself or with other
components in an interference-free arrangement (Figures 2-4, 2-7,
and 2-8).
10.1.4.1.3 For Type S pitot tube combinations with complete
probe assemblies, the calibration point should be located at or
near the center of the duct; however, insertion of a probe sheath
into a small duct may cause significant cross-sectional area
interference and blockage and yield incorrect coefficient values
(Reference 9 in section 17.0). Therefore, to minimize the blockage
effect, the calibration point may be a few inches off-center if
necessary, but no closer to the outer wall of the wind tunnel than
4 inches. The maximum allowable blockage, as determined by a
projected-area model of the probe sheath, is 2 percent or less of
the duct cross-sectional area (Figure 2-10a). If the pitot and/or
probe assembly blocks more than 2 percent of the cross-sectional
area at an insertion point only 4 inches inside the wind tunnel,
the diameter of the wind tunnel must be increased.
10.1.4.2 For those probe assemblies in which pitot tube-nozzle
interference is a factor (i.e., those in which the pitot-nozzle
separation distance fails to meet the specifications illustrated in
Figure 2-7A), the value of Cp(s) depends upon the amount of free
space between the tube and nozzle and, therefore, is a function of
nozzle size. In these instances, separate calibrations shall be
performed with each of the commonly used nozzle sizes in place.
Note that the single-velocity calibration technique is acceptable
for this purpose, even though the larger nozzle sizes (>0.635 cm
or 1/4 in.) are not ordinarily used for isokinetic sampling at
velocities around 910 m/min (3,000 ft/min), which is the
calibration velocity. Note also that it is not necessary to draw an
isokinetic sample during calibration (see Reference 19 in section
17.0).
10.1.4.3 For a probe assembly constructed such that its pitot
tube is always used in the same orientation, only one side of the
pitot tube needs to be calibrated (the side which will face the
flow). The pitot tube must still meet the alignment specifications
of Figure 2-2 or 2-3, however, and must have an average deviation
(σ) value of 0.01 or less (see section 12.4.4).
10.1.5 Field Use and Recalibration.
10.1.5.1 Field Use.
10.1.5.1.1 When a Type S pitot tube (isolated or in an assembly)
is used in the field, the appropriate coefficient value (whether
assigned or obtained by calibration) shall be used to perform
velocity calculations. For calibrated Type S pitot tubes, the A
side coefficient shall be used when the A side of the tube faces
the flow, and the B side coefficient shall be used when the B side
faces the flow. Alternatively, the arithmetic average of the A and
B side coefficient values may be used, irrespective of which side
faces the flow.
10.1.5.1.2 When a probe assembly is used to sample a small duct,
30.5 to 91.4 cm (12 to 36 in.) in diameter, the probe sheath
sometimes blocks a significant part of the duct cross-section,
causing a reduction in the effective value of Cp(s). Consult
Reference 9 (see section 17.0) for details. Conventional
pitot-sampling probe assemblies are not recommended for use in
ducts having inside diameters smaller than 30.5 cm (12 in.) (see
Reference 16 in section 17.0).
10.1.5.2 Recalibration.
10.1.5.2.1 Isolated Pitot Tubes. After each field use, the pitot
tube shall be carefully reexamined in top, side, and end views. If
the pitot face openings are still aligned within the specifications
illustrated in Figure 2-2 and Figure 2-3, it can be assumed that
the baseline coefficient of the pitot tube has not changed. If,
however, the tube has been damaged to the extent that it no longer
meets the specifications of Figure 2-2 and Figure 2-3, the damage
shall either be repaired to restore proper alignment of the face
openings, or the tube shall be discarded.
10.1.5.2.2 Pitot Tube Assemblies. After each field use, check
the face opening alignment of the pitot tube, as in section
10.1.5.2.1. Also, remeasure the intercomponent spacings of the
assembly. If the intercomponent spacings have not changed and the
face opening alignment is acceptable, it can be assumed that the
coefficient of the assembly has not changed. If the face opening
alignment is no longer within the specifications of Figure 2-2 and
Figure 2-3, either repair the damage or replace the pitot tube
(calibrating the new assembly, if necessary). If the intercomponent
spacings have changed, restore the original spacings, or
recalibrate the assembly.
10.2 Standard Pitot Tube (if applicable). If a standard pitot
tube is used for the velocity traverse, the tube shall be
constructed according to the criteria of section 6.7 and shall be
assigned a baseline coefficient value of 0.99. If the standard
pitot tube is used as part of an assembly, the tube shall be in an
interference-free arrangement (subject to the approval of the
Administrator).
10.3 Temperature Sensors.
10.3.1 After each field use, calibrate dial thermometers,
liquid-filled bulb thermometers, thermocouple-potentiometer
systems, and other sensors at a temperature within 10 percent of
the average absolute stack temperature. For temperatures up to 405
°C (761 °F), use an ASTM mercury-in-glass reference thermometer, or
equivalent, as a reference. Alternatively, either a reference
thermocouple and potentiometer (calibrated against NIST standards)
or thermometric fixed points (e.g., ice bath and boiling
water, corrected for barometric pressure) may be used. For
temperatures above 405 °C (761 °F), use a reference
thermocouple-potentiometer system calibrated against NIST standards
or an alternative reference, subject to the approval of the
Administrator.
10.3.2 The temperature data recorded in the field shall be
considered valid. If, during calibration, the absolute temperature
measured with the sensor being calibrated and the reference sensor
agree within 1.5 percent, the temperature data taken in the field
shall be considered valid. Otherwise, the pollutant emission test
shall either be considered invalid or adjustments (if appropriate)
of the test results shall be made, subject to the approval of the
Administrator.
10.4 Barometer. Calibrate the barometer used against a mercury
barometer or NIST-traceable barometer prior to each field test.
11.0 Analytical Procedure
Sample collection and analysis are concurrent for this method
(see section 8.0).
12.0 Data Analysis and Calculations
Carry out calculations, retaining at least one extra significant
figure beyond that of the acquired data. Round off figures after
final calculation.
12.1 Nomenclature.
A = Cross-sectional area of stack, m 2 (ft 2). Bws = Water vapor in
the gas stream (from Method 4 (reference method) or Method 5),
proportion by volume. Cp = Pitot tube coefficient, dimensionless.
Cp(s) = Type S pitot tube coefficient, dimensionless. Cp(std) =
Standard pitot tube coefficient; use 0.99 if the coefficient is
unknown and the tube is designed according to the criteria of
sections 6.7.1 to 6.7.5 of this method. De = Equivalent diameter. K
= 0.127 mm H2O (metric units). 0.005 in. H2O (English units). Kp =
Velocity equation constant. L = Length. Md = Molecular weight of
stack gas, dry basis (see section 8.6), g/g-mole (lb/lb-mole). Ms =
Molecular weight of stack gas, wet basis, g/g-mole (lb/lb-mole). n
= Total number of traverse points. Pbar = Barometric pressure at
measurement site, mm Hg (in. Hg). Pg = Stack static pressure, mm Hg
(in. Hg). Ps = Absolute stack pressure (Pbar + Pg), mm Hg (in. Hg),
Pstd = Standard absolute pressure, 760 mm Hg (29.92 in. Hg). Qsd =
Dry volumetric stack gas flow rate corrected to standard
conditions, dscm/hr (dscf/hr). T = Sensitivity factor for
differential pressure gauges. Ts(abavg) = Average absolute stack
temperature, °K (°R). = 273 + Ts for metric units, = 460 + Ts for
English units. Ts = Stack temperature, °C (°F). = 273 + Ts for
metric units, = 460 + Ts for English units. Tstd = Standard
absolute temperature, 293 °K (528 °R). Vs = Average stack gas
velocity, m/sec (ft/sec). W = Width. Δp = Velocity head of stack
gas, mm H2O (in. H20). Δpi = Individual velocity head reading at
traverse point “i”, mm (in.) H2O. Δpstd = Velocity head measured by
the standard pitot tube, cm (in.) H2O. Δps = Velocity head measured
by the Type S pitot tube, cm (in.) H2O. 3600 = Conversion Factor,
sec/hr. 18.0 = Molecular weight of water, g/g-mole (lb/lb-mole).
12.2 Calculate T as follows:
12.3 Calculate De as follows:
12.4 Calibration of Type S Pitot Tube.
12.4.1 For each of the six pairs of Δp readings (i.e., three
from side A and three from side B) obtained in section 10.1.3,
calculate the value of the Type S pitot tube coefficient according
to Equation 2-3:
12.4.2 Calculate C p(A), the mean A-side coefficient, and C
p(B), the mean B-side coefficient. Calculate the difference between
these two average values.
12.4.3 Calculate the deviation of each of the three A-side
values of Cp(s) from C p(A), and the deviation of each of the three
B-side values of Cp(s) from C p(B), using Equation 2-4:
12.4.4 Calculate σ the average deviation from the mean, for both
the A and B sides of the pitot tube. Use Equation 2-5:
1. Mark, L.S. Mechanical Engineers' Handbook. New York.
McGraw-Hill Book Co., Inc. 1951.
2. Perry, J.H., ed. Chemical Engineers' Handbook. New York.
McGraw-Hill Book Co., Inc. 1960.
3. Shigehara, R.T., W.F. Todd, and W.S. Smith. Significance of
Errors in Stack Sampling Measurements. U.S. Environmental
Protection Agency, Research Triangle Park, N.C. (Presented at the
Annual Meeting of the Air Pollution Control Association, St. Louis,
MO., June 14-19, 1970).
4. Standard Method for Sampling Stacks for Particulate Matter.
In: 1971 Book of ASTM Standards, Part 23. Philadelphia, PA. 1971.
ASTM Designation D 2928-71.
5. Vennard, J.K. Elementary Fluid Mechanics. New York. John
Wiley and Sons, Inc. 1947.
6. Fluid Meters - Their Theory and Application. American Society
of Mechanical Engineers, New York, N.Y. 1959.
7. ASHRAE Handbook of Fundamentals. 1972. p. 208.
8. Annual Book of ASTM Standards, Part 26. 1974. p. 648.
9. Vollaro, R.F. Guidelines for Type S Pitot Tube Calibration.
U.S. Environmental Protection Agency, Research Triangle Park, N.C.
(Presented at 1st Annual Meeting, Source Evaluation Society,
Dayton, OH, September 18, 1975.)
10. Vollaro, R.F. A Type S Pitot Tube Calibration Study. U.S.
Environmental Protection Agency, Emission Measurement Branch,
Research Triangle Park, N.C. July 1974.
11. Vollaro, R.F. The Effects of Impact Opening Misalignment on
the Value of the Type S Pitot Tube Coefficient. U.S. Environmental
Protection Agency, Emission Measurement Branch, Research Triangle
Park, NC. October 1976.
12. Vollaro, R.F. Establishment of a Baseline Coefficient Value
for Properly Constructed Type S Pitot Tubes. U.S. Environmental
Protection Agency, Emission Measurement Branch, Research Triangle
Park, NC. November 1976.
13. Vollaro, R.F. An Evaluation of Single-Velocity Calibration
Technique as a Means of Determining Type S Pitot Tube Coefficients.
U.S. Environmental Protection Agency, Emission Measurement Branch,
Research Triangle Park, NC. August 1975.
14. Vollaro, R.F. The Use of Type S Pitot Tubes for the
Measurement of Low Velocities. U.S. Environmental Protection
Agency, Emission Measurement Branch, Research Triangle Park, NC.
November 1976.
15. Smith, Marvin L. Velocity Calibration of EPA Type Source
Sampling Probe. United Technologies Corporation, Pratt and Whitney
Aircraft Division, East Hartford, CT. 1975.
16. Vollaro, R.F. Recommended Procedure for Sample Traverses in
Ducts Smaller than 12 Inches in Diameter. U.S. Environmental
Protection Agency, Emission Measurement Branch, Research Triangle
Park, NC. November 1976.
17. Ower, E. and R.C. Pankhurst. The Measurement of Air Flow,
4th Ed. London, Pergamon Press. 1966.
18. Vollaro, R.F. A Survey of Commercially Available
Instrumentation for the Measurement of Low-Range Gas Velocities.
U.S. Environmental Protection Agency, Emission Measurement Branch,
Research Triangle Park, NC. November 1976. (Unpublished Paper).
19. Gnyp, A.W., et al. An Experimental Investigation of the
Effect of Pitot Tube-Sampling Probe Configurations on the Magnitude
of the S Type Pitot Tube Coefficient for Commercially Available
Source Sampling Probes. Prepared by the University of Windsor for
the Ministry of the Environment, Toronto, Canada. February
1975.
17.0 Tables, Diagrams, Flowcharts, and Validation Data PLANT DATE RUN NO.
STACK DIA. OR DIMENSIONS, m (in.) BAROMETRIC PRESS., mm Hg (in. Hg)
CROSS SECTIONAL AREA, m 2 (ft 2) OPERATORS PITOT TUBE I.D. NO. AVG.
COEFFICIENT, Cp = LAST DATE CALIBRATED
Figure 2-9. Pitot Tube Calibration Data Method 2A - Direct
Measurement of Gas Volume Through Pipes and Small Ducts Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling) essential to its performance. Some material is
incorporated by reference from other methods in this part.
Therefore, to obtain reliable results, persons using this method
should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2.
1.0 Scope and Application
1.1 This method is applicable for the determination of gas flow
rates in pipes and small ducts, either in-line or at exhaust
positions, within the temperature range of 0 to 50 °C (32 to 122
°F).
1.2 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A gas volume meter is used to measure gas volume directly.
Temperature and pressure measurements are made to allow correction
of the volume to standard conditions.
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies
Specifications for the apparatus are given below. Any other
apparatus that has been demonstrated (subject to approval of the
Administrator) to be capable of meeting the specifications will be
considered acceptable.
6.1 Gas Volume Meter. A positive displacement meter, turbine
meter, or other direct measuring device capable of measuring volume
to within 2 percent. The meter shall be equipped with a temperature
sensor (accurate to within ±2 percent of the minimum absolute
temperature) and a pressure gauge (accurate to within ±2.5 mm Hg).
The manufacturer's recommended capacity of the meter shall be
sufficient for the expected maximum and minimum flow rates for the
sampling conditions. Temperature, pressure, corrosive
characteristics, and pipe size are factors necessary to consider in
selecting a suitable gas meter.
6.2 Barometer. A mercury, aneroid, or other barometer capable of
measuring atmospheric pressure to within ±2.5 mm Hg.
Note:
In many cases, the barometric reading may be obtained from a
nearby National Weather Service station, in which case the station
value (which is the absolute barometric pressure) shall be
requested and an adjustment for elevation differences between the
weather station and sampling point shall be applied at a rate of
minus 2.5 mm (0.1 in.) Hg per 30 m (100 ft) elevation increase or
vice versa for elevation decrease.
6.3 Stopwatch. Capable of measurement to within 1 second.
7.0 Reagents and Standards [Reserved] 8.0 Sample Collection and
Analysis
8.1 Installation. As there are numerous types of pipes and small
ducts that may be subject to volume measurement, it would be
difficult to describe all possible installation schemes. In
general, flange fittings should be used for all connections
wherever possible. Gaskets or other seal materials should be used
to assure leak-tight connections. The volume meter should be
located so as to avoid severe vibrations and other factors that may
affect the meter calibration.
8.2 Leak Test.
8.2.1 A volume meter installed at a location under positive
pressure may be leak-checked at the meter connections by using a
liquid leak detector solution containing a surfactant. Apply a
small amount of the solution to the connections. If a leak exists,
bubbles will form, and the leak must be corrected.
8.2.2 A volume meter installed at a location under negative
pressure is very difficult to test for leaks without blocking flow
at the inlet of the line and watching for meter movement. If this
procedure is not possible, visually check all connections to assure
leak-tight seals.
8.3 Volume Measurement.
8.3.1 For sources with continuous, steady emission flow rates,
record the initial meter volume reading, meter temperature(s),
meter pressure, and start the stopwatch. Throughout the test
period, record the meter temperatures and pressures so that average
values can be determined. At the end of the test, stop the timer,
and record the elapsed time, the final volume reading, meter
temperature, and pressure. Record the barometric pressure at the
beginning and end of the test run. Record the data on a table
similar to that shown in Figure 2A-1.
8.3.2 For sources with noncontinuous, non-steady emission flow
rates, use the procedure in section 8.3.1 with the addition of the
following: Record all the meter parameters and the start and stop
times corresponding to each process cyclical or noncontinuous
event.
9.0 Quality Control
Section
Quality control measure
Effect
10.1-10.4
Sampling equipment
calibration
Ensure accurate measurement of
stack gas flow rate, sample volume.
10.0 Calibration and Standardization
10.1 Volume Meter.
10.1.1 The volume meter is calibrated against a standard
reference meter prior to its initial use in the field. The
reference meter is a spirometer or liquid displacement meter with a
capacity consistent with that of the test meter.
10.1.2 Alternatively, a calibrated, standard pitot may be used
as the reference meter in conjunction with a wind tunnel assembly.
Attach the test meter to the wind tunnel so that the total flow
passes through the test meter. For each calibration run, conduct a
4-point traverse along one stack diameter at a position at least
eight diameters of straight tunnel downstream and two diameters
upstream of any bend, inlet, or air mover. Determine the traverse
point locations as specified in Method 1. Calculate the reference
volume using the velocity values following the procedure in Method
2, the wind tunnel cross-sectional area, and the run time.
10.1.3 Set up the test meter in a configuration similar to that
used in the field installation (i.e., in relation to the
flow moving device). Connect the temperature sensor and pressure
gauge as they are to be used in the field. Connect the reference
meter at the inlet of the flow line, if appropriate for the meter,
and begin gas flow through the system to condition the meters.
During this conditioning operation, check the system for leaks.
10.1.4 The calibration shall be performed during at least three
different flow rates. The calibration flow rates shall be about
0.3, 0.6, and 0.9 times the rated maximum flow rate of the test
meter.
10.1.5 For each calibration run, the data to be collected
include: reference meter initial and final volume readings, the
test meter initial and final volume reading, meter average
temperature and pressure, barometric pressure, and run time. Repeat
the runs at each flow rate at least three times.
10.1.6 Calculate the test meter calibration coefficient as
indicated in section 12.2.
10.1.7 Compare the three Ym values at each of the flow rates
tested and determine the maximum and minimum values. The difference
between the maximum and minimum values at each flow rate should be
no greater than 0.030. Extra runs may be required to complete this
requirement. If this specification cannot be met in six successive
runs, the test meter is not suitable for use. In addition, the
meter coefficients should be between 0.95 and 1.05. If these
specifications are met at all the flow rates, average all the Ym
values from runs meeting the specifications to obtain an average
meter calibration coefficient, Ym.
10.1.8 The procedure above shall be performed at least once for
each volume meter. Thereafter, an abbreviated calibration check
shall be completed following each field test. The calibration of
the volume meter shall be checked with the meter pressure set at
the average value encountered during the field test. Three
calibration checks (runs) shall be performed using this average
flow rate value. Calculate the average value of the calibration
factor. If the calibration has changed by more than 5 percent,
recalibrate the meter over the full range of flow as described
above.
Note:
If the volume meter calibration coefficient values obtained
before and after a test series differ by more than 5 percent, the
test series shall either be voided, or calculations for the test
series shall be performed using whichever meter coefficient value
(i.e., before or after) gives the greater value of pollutant
emission rate.
10.2 Temperature Sensor. After each test series, check the
temperature sensor at ambient temperature. Use an American Society
for Testing and Materials (ASTM) mercury-in-glass reference
thermometer, or equivalent, as a reference. If the sensor being
checked agrees within 2 percent (absolute temperature) of the
reference, the temperature data collected in the field shall be
considered valid. Otherwise, the test data shall be considered
invalid or adjustments of the results shall be made, subject to the
approval of the Administrator.
10.3 Barometer. Calibrate the barometer used against a mercury
barometer or NIST-traceable barometer prior to the field test.
11.0 Analytical Procedure
Sample collection and analysis are concurrent for this method
(see section 8.0).
12.0 Data Analysis and Calculations
Carry out calculations, retaining at least one extra decimal
figure beyond that of the acquired data. Round off figures after
final calculation.
12.1 Nomenclature.
f = Final reading. i = Initial reading. Pbar = Barometric pressure,
mm Hg. Pg = Average static pressure in volume meter, mm Hg. Qs =
Gas flow rate, m 3/min, standard conditions. s = Standard
conditions, 20 °C and 760 mm Hg. Tr = Reference meter average
temperature, °K (°R). Tm = Test meter average temperature, °K (°R).
Vr = Reference meter volume reading, m 3. Vm = Test meter volume
reading, m 3. Ym = Test meter calibration coefficient,
dimensionless. θ = Elapsed test period time, min.
1. Rom, Jerome J. Maintenance, Calibration, and Operation of
Isokinetic Source Sampling Equipment. U.S. Environmental Protection
Agency, Research Triangle Park, NC. Publication No. APTD-0576.
March 1972.
2. Wortman, Martin, R. Vollaro, and P.R. Westlin. Dry Gas Volume
Meter Calibrations. Source Evaluation Society Newsletter. Vol. 2,
No. 2. May 1977.
3. Westlin, P.R., and R.T. Shigehara. Procedure for Calibrating
and Using Dry Gas Volume Meters as Calibration Standards. Source
Evaluation Society Newsletter. Vol. 3, No. 1. February 1978.
17.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
Method 2B - Determination of Exhaust Gas Volume Flow Rate From
Gasoline Vapor Incinerators Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should also have a thorough knowledge of at least the
following additional test methods: Method 1, Method 2, Method 2A,
Method 10, Method 25A, Method 25B.
1.0 Scope and Application
1.1 This method is applicable for the determination of exhaust
volume flow rate from incinerators that process gasoline vapors
consisting primarily of alkanes, alkenes, and/or arenes (aromatic
hydrocarbons). It is assumed that the amount of auxiliary fuel is
negligible.
1.2 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 Organic carbon concentration and volume flow rate are
measured at the incinerator inlet using either Method 25A or Method
25B and Method 2A, respectively. Organic carbon, carbon dioxide
(CO2), and carbon monoxide (CO) concentrations are measured at the
outlet using either Method 25A or Method 25B and Method 10,
respectively. The ratio of total carbon at the incinerator inlet
and outlet is multiplied by the inlet volume to determine the
exhaust volume flow rate.
3.0 Definitions
Same as section 3.0 of Method 10 and Method 25A.
4.0 Interferences
Same as section 4.0 of Method 10.
5.0 Safety
5.1 This method may involve hazardous materials, operations, and
equipment. This test method may not address all of the safety
problems associated with its use. It is the responsibility of the
user of this test method to establish appropriate safety and health
practices and determine the applicability of regulatory limitations
prior to performing this test method.
6.0 Equipment and Supplies
Same as section 6.0 of Method 2A, Method 10, and Method 25A
and/or Method 25B as applicable, with the addition of the
following:
6.1 This analyzer must meet the specifications set forth in
section 6.1.2 of Method 10, except that the span shall be 15
percent CO2 by volume.
7.0 Reagents and Standards
Same as section 7.0 of Method 10 and Method 25A, with the
following addition and exceptions:
7.1 Carbon Dioxide Analyzer Calibration. CO2 gases meeting the
specifications set forth in section 7 of Method 6C are
required.
7.2 Hydrocarbon Analyzer Calibration. Methane shall not be used
as a calibration gas when performing this method.
7.3 Fuel Gas. If Method 25B is used to measure the organic
carbon concentrations at both the inlet and exhaust, no fuel gas is
required.
8.0 Sample Collection and Analysis
8.1 Pre-test Procedures. Perform all pre-test procedures
(e.g., system performance checks, leak checks) necessary to
determine gas volume flow rate and organic carbon concentration in
the vapor line to the incinerator inlet and to determine organic
carbon, carbon monoxide, and carbon dioxide concentrations at the
incinerator exhaust, as outlined in Method 2A, Method 10, and
Method 25A and/or Method 25B as applicable.
8.2 Sampling. At the beginning of the test period, record the
initial parameters for the inlet volume meter according to the
procedures in Method 2A and mark all of the recorder strip charts
to indicate the start of the test. Conduct sampling and analysis as
outlined in Method 2A, Method 10, and Method 25A and/or Method 25B
as applicable. Continue recording inlet organic and exhaust CO2,
CO, and organic concentrations throughout the test. During periods
of process interruption and halting of gas flow, stop the timer and
mark the recorder strip charts so that data from this interruption
are not included in the calculations. At the end of the test
period, record the final parameters for the inlet volume meter and
mark the end on all of the recorder strip charts.
8.3 Post-test Procedures. Perform all post-test procedures
(e.g., drift tests, leak checks), as outlined in Method 2A,
Method 10, and Method 25A and/or Method 25B as applicable.
9.0 Quality Control
Same as section 9.0 of Method 2A, Method 10, and Method 25A.
10.0 Calibration and Standardization
Same as section 10.0 of Method 2A, Method 10, and Method
25A.
Note:
If a manifold system is used for the exhaust analyzers, all the
analyzers and sample pumps must be operating when the analyzer
calibrations are performed.
10.1 If an analyzer output does not meet the specifications of
the method, invalidate the test data for the period. Alternatively,
calculate the exhaust volume results using initial calibration data
and using final calibration data and report both resulting volumes.
Then, for emissions calculations, use the volume measurement
resulting in the greatest emission rate or concentration.
11.0 Analytical Procedure
Sample collection and analysis are concurrent for this method
(see section 8.0).
12.0 Data Analysis and Calculations
Carry out the calculations, retaining at least one extra decimal
figure beyond that of the acquired data. Round off figures after
the final calculation.
12.1 Nomenclature.
COe = Mean carbon monoxide concentration in system exhaust, ppm.
(CO2)a = Ambient carbon dioxide concentration, ppm (if not measured
during the test period, may be assumed to equal the global monthly
mean CO2 concentration posted at
http://www.esrl.noaa.gov/gmd/ccgg/trends/global.html#global_data).
(CO2)e = Mean carbon dioxide concentration in system exhaust, ppm.
HCe = Mean organic concentration in system exhaust as defined by
the calibration gas, ppm. Hci = Mean organic concentration in
system inlet as defined by the calibration gas, ppm. Ke =
Hydrocarbon calibration gas factor for the exhaust hydrocarbon
analyzer, unitless [equal to the number of carbon atoms per
molecule of the gas used to calibrate the analyzer (2 for ethane, 3
for propane, etc.)]. Ki = Hydrocarbon calibration gas factor for
the inlet hydrocarbon analyzer, unitless. Ves = Exhaust gas volume,
m 3. Vis = Inlet gas volume, m 3. Qes = Exhaust gas volume flow
rate, m 3/min. Qis = Inlet gas volume flow rate, m 3/min.
θ = Sample run time, min.
S = Standard conditions: 20 °C, 760 mm Hg.
12.2 Concentrations. Determine mean concentrations of inlet
organics, outlet CO2, outlet CO, and outlet organics according to
the procedures in the respective methods and the analyzers'
calibration curves, and for the time intervals specified in the
applicable regulations.
12.3 Exhaust Gas Volume. Calculate the exhaust gas volume as
follows:
12.4 Exhaust Gas Volume Flow Rate. Calculate the exhaust gas
volume flow rate as follows:
Same as section 16.0 of Method 2A, Method 10, and Method
25A.
17.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
Method 2C - Determination of Gas Velocity and Volumetric Flow Rate
in Small Stacks or Ducts (Standard Pitot Tube) Note:
This method does not include all of the specifications (e.g.,
equipment and supplies) and procedures (e.g., sampling) essential
to its performance. Some material is incorporated by reference from
other methods in this part. Therefore, to obtain reliable results,
persons using this method should also have a thorough knowledge of
at least the following additional test methods: Method 1, Method
2.
1.0 Scope and Application
1.1 This method is applicable for the determination of average
velocity and volumetric flow rate of gas streams in small stacks or
ducts. Limits on the applicability of this method are identical to
those set forth in Method 2, section 1.0, except that this method
is limited to stationary source stacks or ducts less than about
0.30 meter (12 in.) in diameter, or 0.071 m 2 (113 in. 2) in
cross-sectional area, but equal to or greater than about 0.10 meter
(4 in.) in diameter, or 0.0081 m 2 (12.57 in. 2) in cross-sectional
area.
1.2 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 The average gas velocity in a stack or duct is determined
from the gas density and from measurement of velocity heads with a
standard pitot tube.
5.1 This method may involve hazardous materials, operations, and
equipment. This test method may not address all of the safety
problems associated with its use. It is the responsibility of the
user of this test method to establish appropriate safety and health
practices and determine the applicability of regulatory limitations
prior to performing this test method.
6.0 Equipment and Supplies
Same as Method 2, section 6.0, with the exception of the
following:
6.1 Standard Pitot Tube (instead of Type S). A standard pitot
tube which meets the specifications of section 6.7 of Method 2. Use
a coefficient of 0.99 unless it is calibrated against another
standard pitot tube with a NIST-traceable coefficient (see section
10.2 of Method 2).
6.2 Alternative Pitot Tube. A modified hemispherical-nosed pitot
tube (see Figure 2C-1), which features a shortened stem and
enlarged impact and static pressure holes. Use a coefficient of
0.99 unless it is calibrated as mentioned in section 6.1 above.
This pitot tube is useful in particulate liquid droplet-laden gas
streams when a “back purge” is ineffective.
7.0 Reagents and Standards [Reserved] 8.0 Sample Collection and
Analysis
8.1 Follow the general procedures in section 8.0 of Method 2,
except conduct the measurements at the traverse points specified in
Method 1A. The static and impact pressure holes of standard pitot
tubes are susceptible to plugging in particulate-laden gas streams.
Therefore, adequate proof that the openings of the pitot tube have
not plugged during the traverse period must be furnished; this can
be done by taking the velocity head (Δp) heading at the final
traverse point, cleaning out the impact and static holes of the
standard pitot tube by “back-purging” with pressurized air, and
then taking another Δp reading. If the Δp readings made before and
after the air purge are the same (within ±5 percent) the traverse
is acceptable. Otherwise, reject the run. Note that if the Δp at
the final traverse point is unsuitably low, another point may be
selected. If “back purging” at regular intervals is part of the
procedure, then take comparative Δp readings, as above, for the
last two back purges at which suitably high Δp readings are
observed.
9.0 Quality Control
Section
Quality control measure
Effect
10.0
Sampling equipment
calibration
Ensure accurate measurement of
stack gas velocity head.
10.0 Calibration and Standardization
Same as Method 2, sections 10.2 through 10.4.
11.0 Analytical Procedure
Sample collection and analysis are concurrent for this method
(see section 8.0).
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 2D -
Measurement of Gas Volume Flow Rates in Small Pipes and Ducts Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling) essential to its performance. Some material is
incorporated by reference from other methods in this part.
Therefore, to obtain reliable results, persons using this method
should also have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, and Method 2A.
1.0 Scope and Application
1.1 This method is applicable for the determination of the
volumetric flow rates of gas streams in small pipes and ducts. It
can be applied to intermittent or variable gas flows only with
particular caution.
1.2 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 All the gas flow in the pipe or duct is directed through a
rotameter, orifice plate or similar device to measure flow rate or
pressure drop. The device has been previously calibrated in a
manner that insures its proper calibration for the gas being
measured. Absolute temperature and pressure measurements are made
to allow correction of volumetric flow rates to standard
conditions.
5.1 This method may involve hazardous materials, operations, and
equipment. This test method may not address all of the safety
problems associated with its use. It is the responsibility of the
user of this test method to establish appropriate safety and health
practices and determine the applicability of regulatory limitations
prior to performing this test method.
6.0 Equipment and Supplies
Specifications for the apparatus are given below. Any other
apparatus that has been demonstrated (subject to approval of the
Administrator) to be capable of meeting the specifications will be
considered acceptable.
6.1 Gas Metering Rate or Flow Element Device. A rotameter,
orifice plate, or other volume rate or pressure drop measuring
device capable of measuring the stack flow rate to within ±5
percent. The metering device shall be equipped with a temperature
gauge accurate to within ±2 percent of the minimum absolute stack
temperature and a pressure gauge (accurate to within ±5 mm Hg). The
capacity of the metering device shall be sufficient for the
expected maximum and minimum flow rates at the stack gas
conditions. The magnitude and variability of stack gas flow rate,
molecular weight, temperature, pressure, dewpoint, and corrosive
characteristics, and pipe or duct size are factors to consider in
choosing a suitable metering device.
6.2 Barometer. Same as Method 2, section 6.5.
6.3 Stopwatch. Capable of measurement to within 1 second.
7.0 Reagents and Standards [Reserved] 8.0 Sample Collection and
Analysis
8.1 Installation and Leak Check. Same as Method 2A, sections 8.1
and 8.2, respectively.
8.2 Volume Rate Measurement.
8.2.1 Continuous, Steady Flow. At least once an hour, record the
metering device flow rate or pressure drop reading, and the
metering device temperature and pressure. Make a minimum of 12
equally spaced readings of each parameter during the test period.
Record the barometric pressure at the beginning and end of the test
period. Record the data on a table similar to that shown in Figure
2D-1.
8.2.2 Noncontinuous and Nonsteady Flow. Use volume rate devices
with particular caution. Calibration will be affected by variation
in stack gas temperature, pressure and molecular weight. Use the
procedure in section 8.2.1 with the addition of the following:
Record all the metering device parameters on a time interval
frequency sufficient to adequately profile each process cyclical or
noncontinuous event. A multichannel continuous recorder may be
used.
9.0 Quality Control
Section
Quality control measure
Effect
10.0
Sampling equipment
calibration
Ensure accurate measurement of
stack gas flow rate or sample volume.
10.0 Calibration and Standardization
Same as Method 2A, section 10.0, with the following
exception:
10.1 Gas Metering Device. Same as Method 2A, section 10.1,
except calibrate the metering device with the principle stack gas
to be measured (examples: air, nitrogen) against a standard
reference meter. A calibrated dry gas meter is an acceptable
reference meter. Ideally, calibrate the metering device in the
field with the actual gas to be metered. For metering devices that
have a volume rate readout, calculate the test metering device
calibration coefficient, Ym, for each run shown in Equation 2D-2
section 12.3.
10.2 For metering devices that do not have a volume rate
readout, refer to the manufacturer's instructions to calculate the
Vm2 corresponding to each Vr.
10.3 Temperature Gauge. Use the procedure and specifications in
Method 2A, section 10.2. Perform the calibration at a temperature
that approximates field test conditions.
10.4 Barometer. Calibrate the barometer used against a mercury
barometer or NIST-traceable barometer prior to the field test.
11.0 Analytical Procedure.
Sample collection and analysis are concurrent for this method
(see section 8.0).
12.0 Data Analysis and Calculations
12.1 Nomenclature.
Pbar = Barometric pressure, mm Hg (in. Hg). Pm = Test meter average
static pressure, mm Hg (in. Hg). Qr = Reference meter volume flow
rate reading, m 3/min (ft 3/min). Qm = Test meter volume flow rate
reading, m 3/min (ft 3/min). Tr = Absolute reference meter average
temperature, °K (°R). Tm = Absolute test meter average temperature,
°K (°R). Kl = 0.3855 °K/mm Hg for metric units, = 17.65 °R/in. Hg
for English units.
12.2 Gas Flow Rate.
12.3 Test Meter Device Calibration Coefficient. Calculation for
testing metering device calibration coefficient, Ym.
1. Spink, L.K. Principles and Practice of Flowmeter Engineering.
The Foxboro Company. Foxboro, MA. 1967.
2. Benedict, R.P. Fundamentals of Temperature, Pressure, and
Flow Measurements. John Wiley & Sons, Inc. New York, NY. 1969.
3. Orifice Metering of Natural Gas. American Gas Association.
Arlington, VA. Report No. 3. March 1978. 88 pp.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Plant Date
Run No. Sample location Barometric pressure (mm Hg): Start Finish
Operators Metering device No. Calibration coefficient Calibration
gas Date to recalibrate
Time
Flow rate
reading
Static
Pressure
[mm Hg (in. Hg)]
Temperature
°C (°F)
°K (°R)
Average
Figure 2D-1. Volume Flow Rate Measurement Data Method 2E -
Determination of Landfill Gas Production Flow Rate Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should also have a thorough knowledge of at least the
following additional test methods: Methods 2 and 3C.
1.0 Scope and Application
1.1 Applicability. This method applies to the measurement of
landfill gas (LFG) production flow rate from municipal solid waste
landfills and is used to calculate the flow rate of nonmethane
organic compounds (NMOC) from landfills.
1.2 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 Extraction wells are installed either in a cluster of three
or at five dispersed locations in the landfill. A blower is used to
extract LFG from the landfill. LFG composition, landfill pressures,
and orifice pressure differentials from the wells are measured and
the landfill gas production flow rate is calculated.
5.1 Since this method is complex, only experienced personnel
should perform the test. Landfill gas contains methane, therefore
explosive mixtures may exist at or near the landfill. It is
advisable to take appropriate safety precautions when testing
landfills, such as refraining from smoking and installing
explosion-proof equipment.
6.0 Equipment and Supplies
6.1 Well Drilling Rig. Capable of boring a 0.61 m (24 in.)
diameter hole into the landfill to a minimum of 75 percent of the
landfill depth. The depth of the well shall not extend to the
bottom of the landfill or the liquid level.
6.2 Gravel. No fines. Gravel diameter should be appreciably
larger than perforations stated in sections 6.10 and 8.2.
6.3 Bentonite.
6.4 Backfill Material. Clay, soil, and sandy loam have been
found to be acceptable.
6.5 Extraction Well Pipe. Minimum diameter of 3 in., constructed
of polyvinyl chloride (PVC), high density polyethylene (HDPE),
fiberglass, stainless steel, or other suitable nonporous material
capable of transporting landfill gas.
6.6 Above Ground Well Assembly. Valve capable of adjusting gas
flow, such as a gate, ball, or butterfly valve; sampling ports at
the well head and outlet; and a flow measuring device, such as an
in-line orifice meter or pitot tube. A schematic of the aboveground
well head assembly is shown in Figure 2E-1.
6.7 Cap. Constructed of PVC or HDPE.
6.8 Header Piping. Constructed of PVC or HDPE.
6.9 Auger. Capable of boring a 0.15-to 0.23-m (6-to 9-in.)
diameter hole to a depth equal to the top of the perforated section
of the extraction well, for pressure probe installation.
6.10 Pressure Probe. Constructed of PVC or stainless steel
(316), 0.025-m (1-in.). Schedule 40 pipe. Perforate the bottom
two-thirds. A minimum requirement for perforations is slots or
holes with an open area equivalent to four 0.006-m ( 1/4-in.)
diameter holes spaced 90° apart every 0.15 m (6 in.).
6.11 Blower and Flare Assembly. Explosion-proof blower, capable
of extracting LFG at a flow rate of 8.5 m 3/min (300 ft 3/min), a
water knockout, and flare or incinerator.
6.12 Standard Pitot Tube and Differential Pressure Gauge for
Flow Rate Calibration with Standard Pitot. Same as Method 2,
sections 6.7 and 6.8.
6.13 Orifice Meter. Orifice plate, pressure tabs, and pressure
measuring device to measure the LFG flow rate.
6.14 Barometer. Same as Method 4, section 6.1.5.
6.15 Differential Pressure Gauge. Water-filled U-tube manometer
or equivalent, capable of measuring within 0.02 mm Hg (0.01 in.
H2O), for measuring the pressure of the pressure probes.
7.0 Reagents and Standards. Not Applicable 8.0 Sample Collection,
Preservation, Storage, and Transport
8.1 Placement of Extraction Wells. The landfill owner or
operator may install a single cluster of three extraction wells in
a test area or space five equal-volume wells over the landfill. The
cluster wells are recommended but may be used only if the
composition, age of the refuse, and the landfill depth of the test
area can be determined.
8.1.1 Cluster Wells. Consult landfill site records for the age
of the refuse, depth, and composition of various sections of the
landfill. Select an area near the perimeter of the landfill with a
depth equal to or greater than the average depth of the landfill
and with the average age of the refuse between 2 and 10 years old.
Avoid areas known to contain nondecomposable materials, such as
concrete and asbestos. Locate the cluster wells as shown in Figure
2E-2.
8.1.1.1 The age of the refuse in a test area will not be
uniform, so calculate a weighted average age of the refuse as shown
in section 12.2.
8.1.2 Equal Volume Wells. Divide the sections of the landfill
that are at least 2 years old into five areas representing equal
volumes. Locate an extraction well near the center of each
area.
8.2 Installation of Extraction Wells. Use a well drilling rig to
dig a 0.6 m (24 in.) diameter hole in the landfill to a minimum of
75 percent of the landfill depth, not to extend to the bottom of
the landfill or the liquid level. Perforate the bottom two thirds
of the extraction well pipe. A minimum requirement for perforations
is holes or slots with an open area equivalent to 0.01-m (0.5-in.)
diameter holes spaced 90° apart every 0.1 to 0.2 m (4 to 8 in.).
Place the extraction well in the center of the hole and backfill
with gravel to a level 0.30 m (1 ft) above the perforated section.
Add a layer of backfill material 1.2 m (4 ft) thick. Add a layer of
bentonite 0.9 m (3 ft) thick, and backfill the remainder of the
hole with cover material or material equal in permeability to the
existing cover material. The specifications for extraction well
installation are shown in Figure 2E-3.
8.3 Pressure Probes. Shallow pressure probes are used in the
check for infiltration of air into the landfill, and deep pressure
probes are use to determine the radius of influence. Locate
pressure probes along three radial arms approximately 120° apart at
distances of 3, 15, 30, and 45 m (10, 50, 100, and 150 ft) from the
extraction well. The tester has the option of locating additional
pressure probes at distances every 15 m (50 feet) beyond 45 m (150
ft). Example placements of probes are shown in Figure 2E-4. The
15-, 30-, and 45-m, (50-, 100-, and 150-ft) probes from each well,
and any additional probes located along the three radial arms (deep
probes), shall extend to a depth equal to the top of the perforated
section of the extraction wells. All other probes (shallow probes)
shall extend to a depth equal to half the depth of the deep
probes.
8.3.1 Use an auger to dig a hole, 0.15- to 0.23-m (6-to 9-in.)
in diameter, for each pressure probe. Perforate the bottom two
thirds of the pressure probe. A minimum requirement for
perforations is holes or slots with an open area equivalent to four
0.006-m (0.25-in.) diameter holes spaced 90° apart every 0.15 m (6
in.). Place the pressure probe in the center of the hole and
backfill with gravel to a level 0.30 m (1 ft) above the perforated
section. Add a layer of backfill material at least 1.2 m (4 ft)
thick. Add a layer of bentonite at least 0.3 m (1 ft) thick, and
backfill the remainder of the hole with cover material or material
equal in permeability to the existing cover material. The
specifications for pressure probe installation are shown in Figure
2E-5.
8.4 LFG Flow Rate Measurement. Place the flow measurement
device, such as an orifice meter, as shown in Figure 2E-1. Attach
the wells to the blower and flare assembly. The individual wells
may be ducted to a common header so that a single blower, flare
assembly, and flow meter may be used. Use the procedures in section
10.1 to calibrate the flow meter.
8.5 Leak-Check. A leak-check of the above ground system is
required for accurate flow rate measurements and for safety. Sample
LFG at the well head sample port and at the outlet sample port. Use
Method 3C to determine nitrogen (N2) concentrations. Determine the
difference between the well head and outlet N2 concentrations using
the formula in section 12.3. The system passes the leak-check if
the difference is less than 10,000 ppmv.
8.6 Static Testing. Close the control valves on the well heads
during static testing. Measure the gauge pressure (Pg) at each deep
pressure probe and the barometric pressure (Pbar) every 8 hours
(hr) for 3 days. Convert the gauge pressure of each deep pressure
probe to absolute pressure using the equation in section 12.4.
Record as Pi (initial absolute pressure).
8.6.1 For each probe, average all of the 8-hr deep pressure
probe readings (Pi) and record as Pia (average absolute pressure).
Pia is used in section 8.7.5 to determine the maximum radius of
influence.
8.6.2 Measure the static flow rate of each well once during
static testing.
8.7 Short-Term Testing. The purpose of short-term testing is to
determine the maximum vacuum that can be applied to the wells
without infiltration of ambient air into the landfill. The
short-term testing is performed on one well at a time. Burn all LFG
with a flare or incinerator.
8.7.1 Use the blower to extract LFG from a single well at a rate
at least twice the static flow rate of the respective well measured
in section 8.6.2. If using a single blower and flare assembly and a
common header system, close the control valve on the wells not
being measured. Allow 24 hr for the system to stabilize at this
flow rate.
8.7.2 Test for infiltration of air into the landfill by
measuring the gauge pressures of the shallow pressure probes and
using Method 3C to determine the LFG N2 concentration. If the LFG
N2 concentration is less than 5 percent and all of the shallow
probes have a positive gauge pressure, increase the blower vacuum
by 3.7 mm Hg (2 in. H2O), wait 24 hr, and repeat the tests for
infiltration. Continue the above steps of increasing blower vacuum
by 3.7 mm Hg (2 in. H2O), waiting 24 hr, and testing for
infiltration until the concentration of N2 exceeds 5 percent or any
of the shallow probes have a negative gauge pressure. When this
occurs,reduce the blower vacuum to the maximum setting at which the
N2 concentration was less than 5 percent and the gauge pressures of
the shallow probes are positive.
8.7.3 At this blower vacuum, measure atmospheric pressure (Pbar)
every 8 hr for 24 hr, and record the LFG flow rate (Qs) and the
probe gauge pressures (Pf) for all of the probes. Convert the gauge
pressures of the deep probes to absolute pressures for each 8-hr
reading at Qs as shown in section 12.4.
8.7.4 For each probe, average the 8-hr deep pressure probe
absolute pressure readings and record as Pfa (the final average
absolute pressure).
8.7.5 For each probe, compare the initial average pressure (Pia)
from section 8.6.1 to the final average pressure (Pfa). Determine
the furthermost point from the well head along each radial arm
where Pfa ≤Pia. This distance is the maximum radius of influence
(Rm), which is the distance from the well affected by the vacuum.
Average these values to determine the average maximum radius of
influence (Rma).
8.7.6 Calculate the depth (Dst) affected by the extraction well
during the short term test as shown in section 12.6. If the
computed value of Dst exceeds the depth of the landfill, set Dst
equal to the landfill depth.
8.7.7 Calculate the void volume (V) for the extraction well as
shown in section 12.7.
8.7.8 Repeat the procedures in section 8.7 for each well.
8.8 Calculate the total void volume of the test wells (Vv) by
summing the void volumes (V) of each well.
8.9 Long-Term Testing. The purpose of long-term testing is to
extract two void volumes of LFG from the extraction wells. Use the
blower to extract LFG from the wells. If a single Blower and flare
assembly and common header system are used, open all control valves
and set the blower vacuum equal to the highest stabilized blower
vacuum demonstrated by any individual well in section 8.7. Every 8
hr, sample the LFG from the well head sample port, measure the
gauge pressures of the shallow pressure probes, the blower vacuum,
the LFG flow rate, and use the criteria for infiltration in section
8.7.2 and Method 3C to test for infiltration. If infiltration is
detected, do not reduce the blower vacuum, instead reduce the LFG
flow rate from the well by adjusting the control valve on the well
head. Adjust each affected well individually. Continue until the
equivalent of two total void volumes (Vv) have been extracted, or
until Vt = 2Vv.
8.9.1 Calculate Vt, the total volume of LFG extracted from the
wells, as shown in section 12.8.
8.9.2 Record the final stabilized flow rate as Qf and the gauge
pressure for each deep probe. If, during the long term testing, the
flow rate does not stabilize, calculate Qf by averaging the last 10
recorded flow rates.
8.9.3 For each deep probe, convert each gauge pressure to
absolute pressure as in section 12.4. Average these values and
record as Psa. For each probe, compare Pia to Psa. Determine the
furthermost point from the well head along each radial arm where
Psa ≤Pia. This distance is the stabilized radius of influence.
Average these values to determine the average stabilized radius of
influence (Rsa).
8.10 Determine the NMOC mass emission rate using the procedures
in section 12.9 through 12.15.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
10.1
LFG flow rate meter
calibration
Ensures accurate measurement
of LFG flow rate and sample volume
10.0 Calibration and Standardization
10.1 LFG Flow Rate Meter (Orifice) Calibration Procedure. Locate
a standard pitot tube in line with an orifice meter. Use the
procedures in section 8, 12.5, 12.6, and 12.7 of Method 2 to
determine the average dry gas volumetric flow rate for at least
five flow rates that bracket the expected LFG flow rates, except in
section 8.1, use a standard pitot tube rather than a Type S pitot
tube. Method 3C may be used to determine the dry molecular weight.
It may be necessary to calibrate more than one orifice meter in
order to bracket the LFG flow rates. Construct a calibration curve
by plotting the pressure drops across the orifice meter for each
flow rate versus the average dry gas volumetric flow rate in m
3/min of the gas.
11.0 Procedures [Reserved] 12.0 Data Analysis and Calculations
12.1 Nomenclature.
A = Age of landfill, yr. Aavg = Average age of the refuse tested,
yr. Ai = Age of refuse in the ith fraction, yr. Ar = Acceptance
rate, Mg/yr. CNMOC = NMOC concentration, ppmv as hexane (CNMOC =
Ct/6). Co = Concentration of N2 at the outlet, ppmv. Ct = NMOC
concentration, ppmv (carbon equivalent) from Method 25C. Cw =
Concentration of N2 at the wellhead, ppmv. D = Depth affected by
the test wells, m. Dst = Depth affected by the test wells in the
short-term test, m. e = Base number for natural logarithms (2.718).
f = Fraction of decomposable refuse in the landfill. fi = Fraction
of the refuse in the ith section. k = Landfill gas generation
constant, yr−1. Lo = Methane generation potential, m 3/Mg. Lo′ =
Revised methane generation potential to account for the amount of
nondecomposable material in the landfill, m 3/Mg. Mi = Mass of
refuse in the ith section, Mg. Mr = Mass of decomposable refuse
affected by the test well, Mg. Pbar = Atmospheric pressure, mm Hg.
Pf = Final absolute pressure of the deep pressure probes during
short-term testing, mm Hg. Pfa = Average final absolute pressure of
the deep pressure probes during short-term testing, mm Hg. Pgf =
final gauge pressure of the deep pressure probes, mm Hg. Pgi =
Initial gauge pressure of the deep pressure probes, mm Hg. Pi =
Initial absolute pressure of the deep pressure probes during static
testing, mm Hg. Pia = Average initial absolute pressure of the deep
pressure probes during static testing, mm Hg. Ps = Final absolute
pressure of the deep pressure probes during long-term testing, mm
Hg. Psa = Average final absolute pressure of the deep pressure
probes during long-term testing, mm Hg. Qf = Final stabilized flow
rate, m 3/min. Qi = LFG flow rate measured at orifice meter during
the ith interval, m 3/min. Qs = Maximum LFG flow rate at each well
determined by short-term test, m 3/min. Qt = NMOC mass emission
rate, m 3/min. Rm = Maximum radius of influence, m. Rma = Average
maximum radius of influence, m. Rs = Stabilized radius of influence
for an individual well, m. Rsa = Average stabilized radius of
influence, m. ti = Age of section i, yr. tt = Total time of
long-term testing, yr. tvi = Time of the ith interval (usually 8),
hr. V = Void volume of test well, m 3. Vr = Volume of refuse
affected by the test well, m 3. Vt = Total volume of refuse
affected by the long-term testing, m 3. Vv = Total void volume
affected by test wells, m 3. WD = Well depth, m. ρ = Refuse
density, Mg/m 3 (Assume 0.64 Mg/m 3 if data are unavailable).
12.2 Use the following equation to calculate a weighted average
age of landfill refuse.
12.3 Use the following equation to determine the difference in
N2 concentrations (ppmv) at the well head and outlet location.
12.4 Use the following equation to convert the gauge pressure
(Pg) of each initial deep pressure probe to absolute pressure
(Pi).
12.5 Use the following equation to convert the gauge pressures
of the deep probes to absolute pressures for each 8-hr reading at
Qs.
12.6 Use the following equation to calculate the depth (Dst)
affected by the extraction well during the short-term test.
12.7 Use the following equation to calculate the void volume for
the extraction well (V).
12.8 Use the following equation to calculate Vt, the total
volume of LFG extracted from the wells.
12.9 Use the following equation to calculate the depth affected
by the test well. If using cluster wells, use the average depth of
the wells for WD. If the value of D is greater than the depth of
the landfill, set D equal to the landfill depth.
12.10 Use the following equation to calculate the volume of
refuse affected by the test well.
12.11 Use the following equation to calculate the mass affected
by the test well.
12.12 Modify Lo to account for the nondecomposable refuse in the
landfill.
12.13 In the following equation, solve for k (landfill gas
generation constant) by iteration. A suggested procedure is to
select a value for k, calculate the left side of the equation, and
if not equal to zero, select another value for k. Continue this
process until the left hand side of the equation equals zero,
±0.001.
12.14 Use the following equation to determine landfill NMOC mass
emission rate if the yearly acceptance rate of refuse has been
consistent (10 percent) over the life of the landfill.
12.15 Use the following equation to determine landfill NMOC mass
emission rate if the acceptance rate has not been consistent over
the life of the landfill.
2. Emcon Associates, Methane Generation and Recovery from
Landfills. Ann Arbor Science, 1982.
3. The Johns Hopkins University, Brown Station Road Landfill Gas
Resource Assessment, Volume 1: Field Testing and Gas Recovery
Projections. Laurel, Maryland: October 1982.
4. Mandeville and Associates, Procedure Manual for Landfill
Gases Emission Testing.
5. Letter and attachments from Briggum, S., Waste Management of
North America, to Thorneloe, S., EPA. Response to July 28, 1988
request for additional information. August 18, 1988.
6. Letter and attachments from Briggum, S., Waste Management of
North America, to Wyatt, S., EPA. Response to December 7, 1988
request for additional information. January 16, 1989.
17.0 Tables, Diagrams, Flowcharts, and Validation Data
Method 2F - Determination
of Stack Gas Velocity And Volumetric Flow Rate With
Three-Dimensional Probes Note:
This method does not include all of the specifications (e.g.,
equipment and supplies) and procedures (e.g., sampling) essential
to its performance. Some material has been incorporated from other
methods in this part. Therefore, to obtain reliable results, those
using this method should have a thorough knowledge of at least the
following additional test methods: Methods 1, 2, 3 or 3A, and
4.
1.0 Scope and Application 1.1 This method is applicable for the
determination of yaw angle, pitch angle, axial velocity and the
volumetric flow rate of a gas stream in a stack or duct using a
three-dimensional (3-D) probe. This method may be used only when
the average stack or duct gas velocity is greater than or equal to
20 ft/sec. When the above condition cannot be met, alternative
procedures, approved by the Administrator, U.S. Environmental
Protection Agency, shall be used to make accurate flow rate
determinations. 2.0 Summary of Method
2.1 A 3-D probe is used to determine the velocity pressure and
the yaw and pitch angles of the flow velocity vector in a stack or
duct. The method determines the yaw angle directly by rotating the
probe to null the pressure across a pair of symmetrically placed
ports on the probe head. The pitch angle is calculated using
probe-specific calibration curves. From these values and a
determination of the stack gas density, the average axial velocity
of the stack gas is calculated. The average gas volumetric flow
rate in the stack or duct is then determined from the average axial
velocity.
3.0 Definitions
3.1. Angle-measuring Device Rotational Offset (RADO). The
rotational position of an angle-measuring device relative to the
reference scribe line, as determined during the pre-test rotational
position check described in section 8.3.
3.2 Axial Velocity. The velocity vector parallel to the
axis of the stack or duct that accounts for the yaw and pitch angle
components of gas flow. The term “axial” is used herein to indicate
that the velocity and volumetric flow rate results account for the
measured yaw and pitch components of flow at each measurement
point.
3.3 Calibration Pitot Tube. The standard (Prandtl type)
pitot tube used as a reference when calibrating a 3-D probe under
this method.
3.4 Field Test. A set of measurements conducted at a
specific unit or exhaust stack/duct to satisfy the applicable
regulation (e.g., a three-run boiler performance test, a single-or
multiple-load nine-run relative accuracy test).
3.5 Full Scale of Pressure-measuring Device. Full scale
refers to the upper limit of the measurement range displayed by the
device. For bi-directional pressure gauges, full scale includes the
entire pressure range from the lowest negative value to the highest
positive value on the pressure scale.
3.6 Main probe. Refers to the probe head and that section
of probe sheath directly attached to the probe head. The main probe
sheath is distinguished from probe extensions, which are sections
of sheath added onto the main probe to extend its reach.
3.7 “May,” “Must,” “Shall,” “Should,” and the imperative
form of verbs.
3.7.1 “May” is used to indicate that a provision of this
method is optional.
3.7.2 “Must,” “Shall,” and the imperative form of verbs
(such as “record” or “enter”) are used to indicate that a provision
of this method is mandatory.
3.7.3 “Should” is used to indicate that a provision of
this method is not mandatory, but is highly recommended as good
practice.
3.8 Method 1. Refers to 40 CFR part 60, appendix A,
“Method 1 - Sample and velocity traverses for stationary
sources.”
3.9 Method 2. Refers to 40 CFR part 60, appendix A,
“Method 2 - Determination of stack gas velocity and volumetric flow
rate (Type S pitot tube).”
3.10 Method 2G. Refers to 40 CFR part 60, appendix A,
“Method 2G - Determination of stack gas velocity and volumetric
flow rate with two-dimensional probes.”
3.11 Nominal Velocity. Refers to a wind tunnel velocity
setting that approximates the actual wind tunnel velocity to within
±1.5 m/sec (±5 ft/sec).
3.12 Pitch Angle. The angle between the axis of the stack
or duct and the pitch component of flow, i.e., the component of the
total velocity vector in a plane defined by the traverse line and
the axis of the stack or duct. (Figure 2F-1 illustrates the “pitch
plane.”) From the standpoint of a tester facing a test port in a
vertical stack, the pitch component of flow is the vector of flow
moving from the center of the stack toward or away from that test
port. The pitch angle is the angle described by this pitch
component of flow and the vertical axis of the stack.
3.13 Readability. For the purposes of this method,
readability for an analog measurement device is one half of the
smallest scale division. For a digital measurement device, it is
the number of decimals displayed by the device.
3.14 Reference Scribe Line. A line permanently inscribed
on the main probe sheath (in accordance with section 6.1.6.1) to
serve as a reference mark for determining yaw angles.
3.15 Reference Scribe Line Rotational Offset (RSLO). The
rotational position of a probe's reference scribe line relative to
the probe's yaw-null position, as determined during the yaw angle
calibration described in section 10.5.
3.16 Response Time. The time required for the measurement
system to fully respond to a change from zero differential pressure
and ambient temperature to the stable stack or duct pressure and
temperature readings at a traverse point.
3.17 Tested Probe. A 3-D probe that is being
calibrated.
3.18 Three-dimensional (3-D) Probe. A directional probe
used to determine the velocity pressure and yaw and pitch angles in
a flowing gas stream.
3.19 Traverse Line. A diameter or axis extending across a
stack or duct on which measurements of differential pressure and
flow angles are made.
3.20 Wind Tunnel Calibration Location. A point, line,
area, or volume within the wind tunnel test section at, along, or
within which probes are calibrated. At a particular wind tunnel
velocity setting, the average velocity pressures at specified
points at, along, or within the calibration location shall vary by
no more than 2 percent or 0.3 mm H2O (0.01 in. H2O), whichever is
less restrictive, from the average velocity pressure at the
calibration pitot tube location. Air flow at this location shall be
axial, i.e., yaw and pitch angles within ±3°. Compliance with these
flow criteria shall be demonstrated by performing the procedures
prescribed in sections 10.1.1 and 10.1.2. For circular tunnels, no
part of the calibration location may be closer to the tunnel wall
than 10.2 cm (4 in.) or 25 percent of the tunnel diameter,
whichever is farther from the wall. For elliptical or rectangular
tunnels, no part of the calibration location may be closer to the
tunnel wall than 10.2 cm (4 in.) or 25 percent of the applicable
cross-sectional axis, whichever is farther from the wall.
3.21 Wind Tunnel with Documented Axial Flow. A wind
tunnel facility documented as meeting the provisions of sections
10.1.1 (velocity pressure cross-check) and 10.1.2 (axial flow
verification) using the procedures described in these sections or
alternative procedures determined to be technically equivalent.
3.22 Yaw Angle. The angle between the axis of the stack
or duct and the yaw component of flow, i.e., the component of the
total velocity vector in a plane perpendicular to the traverse line
at a particular traverse point. (Figure 2F-1 illustrates the “yaw
plane.”) From the standpoint of a tester facing a test port in a
vertical stack, the yaw component of flow is the vector of flow
moving to the left or right from the center of the stack as viewed
by the tester. (This is sometimes referred to as “vortex flow,”
i.e., flow around the centerline of a stack or duct.) The yaw angle
is the angle described by this yaw component of flow and the
vertical axis of the stack. The algebraic sign convention is
illustrated in Figure 2F-2.
3.23 Yaw Nulling. A procedure in which a probe is rotated
about its axis in a stack or duct until a zero differential
pressure reading (“yaw null”) is obtained. When a 3-D probe is
yaw-nulled, its impact pressure port (P1) faces directly into the
direction of flow in the stack or duct and the differential
pressure between pressure ports P2 and P3 is zero.
4.0 Interferences [Reserved] 5.0 Safety
5.1 This test method may involve hazardous operations and the
use of hazardous materials or equipment. This method does not
purport to address all of the safety problems associated with its
use. It is the responsibility of the user to establish and
implement appropriate safety and health practices and to determine
the applicability of regulatory limitations before using this test
method.
6.0 Equipment and Supplies
6.1 Three-dimensional Probes. The 3-D probes as specified
in subsections 6.1.1 through 6.1.3 below qualify for use based on
comprehensive wind tunnel and field studies involving both
inter-and intra-probe comparisons by multiple test teams. Other
types of probes shall not be used unless approved by the
Administrator. Each 3-D probe shall have a unique identification
number or code permanently marked on the main probe sheath. The
minimum recommended diameter of the sensing head of any probe used
under this method is 2.5 cm (1 in.). Each probe shall be calibrated
prior to use according to the procedures in section 10.
Manufacturer-supplied calibration data shall be used as example
information only, except when the manufacturer calibrates the 3-D
probe as specified in section 10 and provides complete
documentation.
6.1.1 Five-hole prism-shaped probe. This type of probe
consists of five pressure taps in the flat facets of a prism-shaped
sensing head. The pressure taps are numbered 1 through 5, with the
pressures measured at each hole referred to as P1, P2, P3, P4, and
P5, respectively. Figure 2F-3 is an illustration of the placement
of pressure taps on a commonly available five-hole prism-shaped
probe, the 2.5-cm (1-in.) DAT probe. (Note: Mention of trade names
or specific products does not constitute endorsement by the U.S.
Environmental Protection Agency.) The numbering arrangement for the
prism-shaped sensing head presented in Figure 2F-3 shall be
followed for correct operation of the probe. A brief description of
the probe measurements involved is as follows: the differential
pressure P2-P3 is used to yaw null the probe and determine the yaw
angle; the differential pressure P4-P5 is a function of pitch
angle; and the differential pressure P1-P2 is a function of total
velocity.
6.1.2 Five-hole spherical probe. This type of probe
consists of five pressure taps in a spherical sensing head. As with
the prism-shaped probe, the pressure taps are numbered 1 through 5,
with the pressures measured at each hole referred to as P1, P2, P3,
P4, and P5, respectively. However, the P4 and P5 pressure taps are
in the reverse location from their respective positions on the
prism-shaped probe head. The differential pressure P2-P3 is used to
yaw null the probe and determine the yaw angle; the differential
pressure P4-P5 is a function of pitch angle; and the differential
pressure P1-P2 is a function of total velocity. A diagram of a
typical spherical probe sensing head is presented in Figure 2F-4.
Typical probe dimensions are indicated in the illustration.
6.1.3 A manual 3-D probe refers to a five-hole
prism-shaped or spherical probe that is positioned at individual
traverse points and yaw nulled manually by an operator. An
automated 3-D probe refers to a system that uses a
computer-controlled motorized mechanism to position the five-hole
prism-shaped or spherical head at individual traverse points and
perform yaw angle determinations.
6.1.4 Other three-dimensional probes. [Reserved]
6.1.5 Probe sheath. The probe shaft shall include an
outer sheath to: (1) provide a surface for inscribing a permanent
reference scribe line, (2) accommodate attachment of an
angle-measuring device to the probe shaft, and (3) facilitate
precise rotational movement of the probe for determining yaw
angles. The sheath shall be rigidly attached to the probe assembly
and shall enclose all pressure lines from the probe head to the
farthest position away from the probe head where an angle-measuring
device may be attached during use in the field. The sheath of the
fully assembled probe shall be sufficiently rigid and straight at
all rotational positions such that, when one end of the probe shaft
is held in a horizontal position, the fully extended probe meets
the horizontal straightness specifications indicated in section 8.2
below.
6.1.6 Scribe lines.
6.1.6.1 Reference scribe line. A permanent line, no
greater than 1.6 mm (1/16 in.) in width, shall be inscribed on each
manual probe that will be used to determine yaw angles of flow.
This line shall be placed on the main probe sheath in accordance
with the procedures described in section 10.4 and is used as a
reference position for installation of the yaw angle-measuring
device on the probe. At the discretion of the tester, the scribe
line may be a single line segment placed at a particular position
on the probe sheath (e.g., near the probe head), multiple line
segments placed at various locations along the length of the probe
sheath (e.g., at every position where a yaw angle-measuring device
may be mounted), or a single continuous line extending along the
full length of the probe sheath.
6.1.6.2 Scribe line on probe extensions. A permanent line
may also be inscribed on any probe extension that will be attached
to the main probe in performing field testing. This allows a yaw
angle-measuring device mounted on the extension to be readily
aligned with the reference scribe line on the main probe
sheath.
6.1.6.3 Alignment specifications. This specification
shall be met separately, using the procedures in section 10.4.1, on
the main probe and on each probe extension. The rotational position
of the scribe line or scribe line segments on the main probe or any
probe extension must not vary by more than 2°. That is, the
difference between the minimum and maximum of all of the rotational
angles that are measured along the full length of the main probe or
the probe extension must not exceed 2°.
6.1.7 Probe and system characteristics to ensure horizontal
stability.
6.1.7.1 For manual probes, it is recommended that the effective
length of the probe (coupled with a probe extension, if necessary)
be at least 0.9 m (3 ft.) longer than the farthest traverse point
mark on the probe shaft away from the probe head. The operator
should maintain the probe's horizontal stability when it is fully
inserted into the stack or duct. If a shorter probe is used, the
probe should be inserted through a bushing sleeve, similar to the
one shown in Figure 2F-5, that is installed on the test port; such
a bushing shall fit snugly around the probe and be secured to the
stack or duct entry port in such a manner as to maintain the
probe's horizontal stability when fully inserted into the stack or
duct.
6.1.7.2 An automated system that includes an external probe
casing with a transport system shall have a mechanism for
maintaining horizontal stability comparable to that obtained by
manual probes following the provisions of this method. The
automated probe assembly shall also be constructed to maintain the
alignment and position of the pressure ports during sampling at
each traverse point. The design of the probe casing and transport
system shall allow the probe to be removed from the stack or duct
and checked through direct physical measurement for angular
position and insertion depth.
6.1.8 The tubing that is used to connect the probe and the
pressure-measuring device should have an inside diameter of at
least 3.2 mm (1/8 in.), to reduce the time required for pressure
equilibration, and should be as short as practicable.
6.2 Yaw Angle-measuring Device. One of the following devices
shall be used for measurement of the yaw angle of flow.
6.2.1 Digital inclinometer. This refers to a digital device
capable of measuring and displaying the rotational position of the
probe to within ±1°. The device shall be able to be locked into
position on the probe sheath or probe extension, so that it
indicates the probe's rotational position throughout the test. A
rotational position collar block that can be attached to the probe
sheath (similar to the collar shown in Figure 2F-6) may be required
to lock the digital inclinometer into position on the probe
sheath.
6.2.2 Protractor wheel and pointer assembly. This apparatus,
similar to that shown in Figure 2F-7, consists of the following
components.
6.2.2.1 A protractor wheel that can be attached to a port
opening and set in a fixed rotational position to indicate the yaw
angle position of the probe's scribe line relative to the
longitudinal axis of the stack or duct. The protractor wheel must
have a measurement ring on its face that is no less than 17.8 cm (7
in.) in diameter, shall be able to be rotated to any angle and then
locked into position on the stack or duct port, and shall indicate
angles to a resolution of 1°.
6.2.2.2 A pointer assembly that includes an indicator needle
mounted on a collar that can slide over the probe sheath and be
locked into a fixed rotational position on the probe sheath. The
pointer needle shall be of sufficient length, rigidity, and
sharpness to allow the tester to determine the probe's angular
position to within 1° from the markings on the protractor wheel.
Corresponding to the position of the pointer, the collar must have
a scribe line to be used in aligning the pointer with the scribe
line on the probe sheath.
6.2.3 Other yaw angle-measuring devices. Other angle-measuring
devices with a manufacturer's specified precision of 1° or better
may be used, if approved by the Administrator.
6.3 Probe Supports and Stabilization Devices. When probes are
used for determining flow angles, the probe head should be kept in
a stable horizontal position. For probes longer than 3.0 m (10
ft.), the section of the probe that extends outside the test port
shall be secured. Three alternative devices are suggested for
maintaining the horizontal position and stability of the probe
shaft during flow angle determinations and velocity pressure
measurements: (1) Monorails installed above each port, (2) probe
stands on which the probe shaft may be rested, or (3) bushing
sleeves of sufficient length secured to the test ports to maintain
probes in a horizontal position. Comparable provisions shall be
made to ensure that automated systems maintain the horizontal
position of the probe in the stack or duct. The physical
characteristics of each test platform may dictate the most suitable
type of stabilization device. Thus, the choice of a specific
stabilization device is left to the judgment of the testers.
6.4 Differential Pressure Gauges. The pressure (ΔP) measuring
devices used during wind tunnel calibrations and field testing
shall be either electronic manometers (e.g., pressure transducers),
fluid manometers, or mechanical pressure gauges (e.g., MagnehelicΔ
gauges). Use of electronic manometers is recommended. Under low
velocity conditions, use of electronic manometers may be necessary
to obtain acceptable measurements.
6.4.1 Differential pressure-measuring device. This refers to a
device capable of measuring pressure differentials and having a
readability of ±1 percent of full scale. The device shall be
capable of accurately measuring the maximum expected pressure
differential. Such devices are used to determine the following
pressure measurements: velocity pressure, static pressure, yaw-null
pressure, and pitch-angle pressure. For an inclined-vertical
manometer, the readability specification of ±1 percent shall be met
separately using the respective full-scale upper limits of the
inclined and vertical portions of the scales. To the extent
practicable, the device shall be selected such that most of the
pressure readings are between 10 and 90 percent of the device's
full-scale measurement range (as defined in section 3.5). Typical
velocity pressure (P1-P2) ranges for both the prism-shaped probe
and the spherical probe are 0 to 1.3 cm H2O (0 to 0.5 in. H2O), 0
to 5.1 cm H2O (0 to 2 in. H2O), and 0 to 12.7 cm H2O (0 to 5 in.
H2O). The pitch angle (P4-P5) pressure range is typically −6.4 to +
6.4 mm H2O (−0.25 to + 0.25 in. H2O) or −12.7 to + 12.7 mm H2O
(−0.5 to + 0.5 in. H2O) for the prism-shaped probe, and −12.7 to +
12.7 mm H2O (−0.5 to + 0.5 in. H2O) or −5.1 to + 5.1 cm H2O (−2 to
+ 2 in. H2O) for the spherical probe. The pressure range for the
yaw null (P2-P3) readings is typically −12.7 to + 12.7 mm H2O (−0.5
to + 0.5 in. H2O) for both probe types. In addition,
pressure-measuring devices should be selected such that the zero
does not drift by more than 5 percent of the average expected
pressure readings to be encountered during the field test. This is
particularly important under low pressure conditions.
6.4.2 Gauge used for yaw nulling. The differential
pressure-measuring device chosen for yaw nulling the probe during
the wind tunnel calibrations and field testing shall be
bi-directional, i.e., capable of reading both positive and negative
differential pressures. If a mechanical, bi-directional pressure
gauge is chosen, it shall have a full-scale range no greater than
2.6 cm H2O (1 in. H2O) [i.e., −1.3 to + 1.3 cm H2O (−0.5 in. to +
0.5 in.)].
6.4.3 Devices for calibrating differential pressure-measuring
devices. A precision manometer (e.g., a U-tube, inclined, or
inclined-vertical manometer, or micromanometer) or NIST (National
Institute of Standards and Technology) traceable pressure source
shall be used for calibrating differential pressure-measuring
devices. The device shall be maintained under laboratory conditions
or in a similar protected environment (e.g., a climate-controlled
trailer). It shall not be used in field tests. The precision
manometer shall have a scale gradation of 0.3 mm H2O (0.01 in.
H2O), or less, in the range of 0 to 5.1 cm H2O (0 to 2 in. H2O) and
2.5 mm H2O (0.1 in. H2O), or less, in the range of 5.1 to 25.4 cm
H2O (2 to 10 in. H2O). The manometer shall have manufacturer's
documentation that it meets an accuracy specification of at least
0.5 percent of full scale. The NIST-traceable pressure source shall
be recertified annually.
6.4.4 Devices used for post-test calibration check. A precision
manometer meeting the specifications in section 6.4.3, a
pressure-measuring device or pressure source with a documented
calibration traceable to NIST, or an equivalent device approved by
the Administrator shall be used for the post-test calibration
check. The pressure-measuring device shall have a readability
equivalent to or greater than the tested device. The pressure
source shall be capable of generating pressures between 50 and 90
percent of the range of the tested device and known to within ±1
percent of the full scale of the tested device. The pressure source
shall be recertified annually.
6.5 Data Display and Capture Devices. Electronic manometers (if
used) shall be coupled with a data display device (such as a
digital panel meter, personal computer display, or strip chart)
that allows the tester to observe and validate the pressure
measurements taken during testing. They shall also be connected to
a data recorder (such as a data logger or a personal computer with
data capture software) that has the ability to compute and retain
the appropriate average value at each traverse point, identified by
collection time and traverse point.
6.6 Temperature Gauges. For field tests, a thermocouple or
resistance temperature detector (RTD) capable of measuring
temperature to within ±3 °C (±5 °F) of the stack or duct
temperature shall be used. The thermocouple shall be attached to
the probe such that the sensor tip does not touch any metal and is
located on the opposite side of the probe head from the pressure
ports so as not to interfere with the gas flow around the probe
head. The position of the thermocouple relative to the pressure
port face openings shall be in the same configuration as used for
the probe calibrations in the wind tunnel. Temperature gauges used
for wind tunnel calibrations shall be capable of measuring
temperature to within ±0.6 °C (±1 °F) of the temperature of the
flowing gas stream in the wind tunnel.
6.7 Stack or Duct Static Pressure Measurement. The
pressure-measuring device used with the probe shall be as specified
in section 6.4 of this method. The static tap of a standard
(Prandtl type) pitot tube or one leg of a Type S pitot tube with
the face opening planes positioned parallel to the gas flow may be
used for this measurement. Also acceptable is the pressure
differential reading of P1-Pbar from a five-hole prism-shaped probe
(e.g., Type DA or DAT probe) with the P1 pressure port face opening
positioned parallel to the gas flow in the same manner as the Type
S probe. However, the spherical probe, as specified in section
6.1.2, is unable to provide this measurement and shall not be used
to take static pressure measurements. Static pressure measurement
is further described in section 8.11.
6.8 Barometer. Same as Method 2, section 2.5.
6.9 Gas Density Determination Equipment. Method 3 or 3A shall be
used to determine the dry molecular weight of the stack gas. Method
4 shall be used for moisture content determination and computation
of stack gas wet molecular weight. Other methods may be used, if
approved by the Administrator.
6.10 Calibration Pitot Tube. Same as Method 2, section 2.7.
6.11 Wind Tunnel for Probe Calibration. Wind tunnels used to
calibrate velocity probes must meet the following design
specifications.
6.11.1 Test section cross-sectional area. The flowing gas stream
shall be confined within a circular, rectangular, or elliptical
duct. The cross-sectional area of the tunnel must be large enough
to ensure fully developed flow in the presence of both the
calibration pitot tube and the tested probe. The calibration site,
or “test section,” of the wind tunnel shall have a minimum diameter
of 30.5 cm (12 in.) for circular or elliptical duct cross-sections
or a minimum width of 30.5 cm (12 in.) on the shorter side for
rectangular cross-sections. Wind tunnels shall meet the probe
blockage provisions of this section and the qualification
requirements prescribed in section 10.1. The projected area of the
portion of the probe head, shaft, and attached devices inside the
wind tunnel during calibration shall represent no more than 4
percent of the cross-sectional area of the tunnel. The projected
area shall include the combined area of the calibration pitot tube
and the tested probe if both probes are placed simultaneously in
the same cross-sectional plane in the wind tunnel, or the larger
projected area of the two probes if they are placed alternately in
the wind tunnel.
6.11.2 Velocity range and stability. The wind tunnel should be
capable of maintaining velocities between 6.1 m/sec and 30.5 m/sec
(20 ft/sec and 100 ft/sec). The wind tunnel shall produce fully
developed flow patterns that are stable and parallel to the axis of
the duct in the test section.
6.11.3 Flow profile at the calibration location. The wind tunnel
shall provide axial flow within the test section calibration
location (as defined in section 3.20). Yaw and pitch angles in the
calibration location shall be within ±3° of 0°. The procedure for
determining that this requirement has been met is described in
section 10.1.2.
6.11.4 Entry ports in the wind tunnel test section.
6.11.4.1 Port for tested probe. A port shall be constructed for
the tested probe. The port should have an elongated slot parallel
to the axis of the duct at the test section. The elongated slot
should be of sufficient length to allow attaining all the pitch
angles at which the probe will be calibrated for use in the field.
To facilitate alignment of the probe during calibration, the test
section should include a window constructed of a transparent
material to allow the tested probe to be viewed. This port shall be
located to allow the head of the tested probe to be positioned
within the calibration location (as defined in section 3.20) at all
pitch angle settings.
6.11.4.2 Port for verification of axial flow. Depending on the
equipment selected to conduct the axial flow verification
prescribed in section 10.1.2, a second port, located 90° from the
entry port for the tested probe, may be needed to allow
verification that the gas flow is parallel to the central axis of
the test section. This port should be located and constructed so as
to allow one of the probes described in section 10.1.2.2 to access
the same test point(s) that are accessible from the port described
in section 6.11.4.1.
6.11.4.3 Port for calibration pitot tube. The calibration pitot
tube shall be used in the port for the tested probe or a separate
entry port. In either case, all measurements with the calibration
pitot tube shall be made at the same point within the wind tunnel
over the course of a probe calibration. The measurement point for
the calibration pitot tube shall meet the same specifications for
distance from the wall and for axial flow as described in section
3.20 for the wind tunnel calibration location.
6.11.5 Pitch angle protractor plate. A protractor plate shall be
attached directly under the port used with the tested probe and set
in a fixed position to indicate the pitch angle position of the
probe relative to the longitudinal axis of the wind tunnel duct
(similar to Figure 2F-8). The protractor plate shall indicate
angles in 5° increments with a minimum resolution of ±2°. The
tested probe shall be able to be locked into position at the
desired pitch angle delineated on the protractor. The probe head
position shall be maintained within the calibration location (as
defined in section 3.20) in the test section of the wind tunnel
during all tests across the range of pitch angles.
7.0 Reagents and Standards [Reserved] 8.0 Sample Collection and
Analysis
8.1 Equipment Inspection and Set-Up
8.1.1 All probes, differential pressure-measuring devices, yaw
angle-measuring devices, thermocouples, and barometers shall have a
current, valid calibration before being used in a field test. (See
sections 10.3.3, 10.3.4, and 10.5 through10.10 for the applicable
calibration requirements.)
8.1.2 Before each field use of a 3-D probe, perform a visual
inspection to verify the physical condition of the probe head
according to the procedures in section 10.2. Record the inspection
results on a form similar to Table 2F-1. If there is visible damage
to the 3-D probe, the probe shall not be used until it is
recalibrated.
8.1.3 After verifying that the physical condition of the probe
head is acceptable, set up the apparatus using lengths of flexible
tubing that are as short as practicable. Surge tanks installed
between the probe and pressure-measuring device may be used to
dampen pressure fluctuations provided that an adequate measurement
response time (see section 8.8) is maintained.
8.2 Horizontal Straightness Check. A horizontal straightness
check shall be performed before the start of each field test,
except as otherwise specified in this section. Secure the fully
assembled probe (including the probe head and all probe shaft
extensions) in a horizontal position using a stationary support at
a point along the probe shaft approximating the location of the
stack or duct entry port when the probe is sampling at the farthest
traverse point from the stack or duct wall. The probe shall be
rotated to detect bends. Use an angle-measuring device or
trigonometry to determine the bend or sag between the probe head
and the secured end. (See Figure 2F-9.) Probes that are bent or sag
by more than 5° shall not be used. Although this check does not
apply when the probe is used for a vertical traverse, care should
be taken to avoid the use of bent probes when conducting vertical
traverses. If the probe is constructed of a rigid steel material
and consists of a main probe without probe extensions, this check
need only be performed before the initial field use of the probe,
when the probe is recalibrated, when a change is made to the design
or material of the probe assembly, and when the probe becomes bent.
With such probes, a visual inspection shall be made of the fully
assembled probe before each field test to determine if a bend is
visible. The probe shall be rotated to detect bends. The inspection
results shall be documented in the field test report. If a bend in
the probe is visible, the horizontal straightness check shall be
performed before the probe is used.
8.3 Rotational Position Check. Before each field test, and each
time an extension is added to the probe during a field test, a
rotational position check shall be performed on all manually
operated probes (except as noted in section 8.3.5, below) to ensure
that, throughout testing, the angle-measuring device is either:
aligned to within ±1° of the rotational position of the reference
scribe line; or is affixed to the probe such that the rotational
offset of the device from the reference scribe line is known to
within ±1°. This check shall consist of direct measurements of the
rotational positions of the reference scribe line and
angle-measuring device sufficient to verify that these
specifications are met. Annex A in section 18 of this method gives
recommended procedures for performing the rotational position
check, and Table 2F-2 gives an example data form. Procedures other
than those recommended in Annex A in section 18 may be used,
provided they demonstrate whether the alignment specification is
met and are explained in detail in the field test report.
8.3.1 Angle-measuring device rotational offset. The tester shall
maintain a record of the angle-measuring device rotational offset,
RADO, as defined in section 3.1. Note that RADO is assigned a value
of 0° when the angle-measuring device is aligned to within ±1° of
the rotational position of the reference scribe line. The RADO
shall be used to determine the yaw angle of flow in accordance with
section 8.9.4.
8.3.2 Sign of angle-measuring device rotational offset. The sign
of RADO is positive when the angle-measuring device (as viewed from
the “tail” end of the probe) is positioned in a clockwise direction
from the reference scribe line and negative when the device is
positioned in a counterclockwise direction from the reference
scribe line.
8.3.3 Angle-measuring devices that can be independently adjusted
(e.g., by means of a set screw), after being locked into position
on the probe sheath, may be used. However, the RADO must also take
into account this adjustment.
8.3.4 Post-test check. If probe extensions remain attached to
the main probe throughout the field test, the rotational position
check shall be repeated, at a minimum, at the completion of the
field test to ensure that the angle-measuring device has remained
within ±2° of its rotational position established prior to testing.
At the discretion of the tester, additional checks may be conducted
after completion of testing at any sample port or after any test
run. If the ±2° specification is not met, all measurements made
since the last successful rotational position check must be
repeated. section 18.1.1.3 of Annex A provides an example procedure
for performing the post-test check.
8.3.5 Exceptions.
8.3.5.1 A rotational position check need not be performed if,
for measurements taken at all velocity traverse points, the yaw
angle-measuring device is mounted and aligned directly on the
reference scribe line specified in sections 6.1.6.1 and 6.1.6.3 and
no independent adjustments, as described in section 8.3.3, are made
to the device's rotational position.
8.3.5.2 If extensions are detached and re-attached to the probe
during a field test, a rotational position check need only be
performed the first time an extension is added to the probe, rather
than each time the extension is re-attached, if the probe extension
is designed to be locked into a mechanically fixed rotational
position (e.g., through use of interlocking grooves) that can
re-establish the initial rotational position to within ±1°.
8.4 Leak Checks. A pre-test leak check shall be conducted before
each field test. A post-test check shall be performed at the end of
the field test, but additional leak checks may be conducted after
any test run or group of test runs. The post-test check may also
serve as the pre-test check for the next group of test runs. If any
leak check is failed, all runs since the last passed leak check are
invalid. While performing the leak check procedures, also check
each pressure device's responsiveness to the changes in
pressure.
8.4.1 To perform the leak check, pressurize the probe's P1
pressure port until at least 7.6 cm H2O (3 in. H2O) pressure, or a
pressure corresponding to approximately 75 percent of the
pressure-measuring device's measurement scale, whichever is less,
registers on the device; then, close off the pressure port. The
pressure shall remain stable [±2.5 mm H2O (±0.10 in. H2O)] for at
least 15 seconds. Check the P2, P3, P4, and P5 pressure ports in
the same fashion. Other leak-check procedures may be used, if
approved by the Administrator.
8.5 Zeroing the Differential Pressure-measuring Device. Zero
each differential pressure-measuring device, including the device
used for yaw nulling, before each field test. At a minimum, check
the zero after each field test. A zero check may also be performed
after any test run or group of test runs. For fluid manometers and
mechanical pressure gauges (e.g., MagnehelicΔ gauges), the zero
reading shall not deviate from zero by more than ±0.8 mm H2O (±0.03
in. H2O) or one minor scale division, whichever is greater, between
checks. For electronic manometers, the zero reading shall not
deviate from zero between checks by more than: ±0.3 mm H2O (±0.01
in. H2O), for full scales less than or equal to 5.1 cm H2O (2.0 in.
H2O); or ±0.8 mm H2O (±0.03 in. H2O), for full scales greater than
5.1 cm H2O (2.0 in. H2O). (Note: If negative zero drift is not
directly readable, estimate the reading based on the position of
the gauge oil in the manometer or of the needle on the pressure
gauge.) In addition, for all pressure-measuring devices except
those used exclusively for yaw nulling, the zero reading shall not
deviate from zero by more than 5 percent of the average measured
differential pressure at any distinct process condition or load
level. If any zero check is failed at a specific process condition
or load level, all runs conducted at that process condition or load
level since the last passed zero check are invalid.
8.6 Traverse Point Verification. The number and location of the
traverse points shall be selected based on Method 1 guidelines. The
stack or duct diameter and port nipple lengths, including any
extension of the port nipples into stack or duct, shall be verified
the first time the test is performed; retain and use this
information for subsequent field tests, updating it as required.
Physically measure the stack or duct dimensions or use a calibrated
laser device; do not use engineering drawings of the stack or duct.
The probe length necessary to reach each traverse point shall be
recorded to within ±6.4 mm (±1/4 in.) and, for manual probes,
marked on the probe sheath. In determining these lengths, the
tester shall take into account both the distance that the port
flange projects outside of the stack and the depth that any port
nipple extends into the gas stream. The resulting point positions
shall reflect the true distances from the inside wall of the stack
or duct, so that when the tester aligns any of the markings with
the outside face of the stack port, the probe's impact port shall
be located at the appropriate distance from the inside wall for the
respective Method 1 traverse point. Before beginning testing at a
particular location, an out-of-stack or duct verification shall be
performed on each probe that will be used to ensure that these
position markings are correct. The distances measured during the
verification must agree with the previously calculated distances to
within ±1/4 in. For manual probes, the traverse point positions
shall be verified by measuring the distance of each mark from the
probe's P1 pressure port. A comparable out-of-stack test shall be
performed on automated probe systems. The probe shall be extended
to each of the prescribed traverse point positions. Then, the
accuracy of the positioning for each traverse point shall be
verified by measuring the distance between the port flange and the
probe's P1 pressure port.
8.7 Probe Installation. Insert the probe into the test port. A
solid material shall be used to seal the port.
8.8 System Response Time. Determine the response time of the
probe measurement system. Insert and position the “cold” probe (at
ambient temperature and pressure) at any Method 1 traverse point.
Read and record the probe's P1-P2 differential pressure,
temperature, and elapsed time at 15-second intervals until stable
readings for both pressure and temperature are achieved. The
response time is the longer of these two elapsed times. Record the
response time.
8.9 Sampling.
8.9.1 Yaw angle measurement protocol. With manual probes, yaw
angle measurements may be obtained in two alternative ways during
the field test, either by using a yaw angle-measuring device (e.g.,
digital inclinometer) affixed to the probe, or using a protractor
wheel and pointer assembly. For horizontal traversing, either
approach may be used. For vertical traversing, i.e., when measuring
from on top or into the bottom of a horizontal duct, only the
protractor wheel and pointer assembly may be used. With automated
probes, curve-fitting protocols may be used to obtain yaw-angle
measurements.
8.9.1.1 If a yaw angle-measuring device affixed to the probe is
to be used, lock the device on the probe sheath, aligning it either
on the reference scribe line or in the rotational offset position
established under section 8.3.1.
8.9.1.2 If a protractor wheel and pointer assembly is to be
used, follow the procedures in Annex B of this method.
8.9.1.3 Other yaw angle-determination procedures. If approved by
the Administrator, other procedures for determining yaw angle may
be used, provided that they are verified in a wind tunnel to be
able to perform the yaw angle calibration procedure as described in
section 10.5.
8.9.2 Sampling strategy. At each traverse point, first yaw-null
the probe, as described in section 8.9.3, below. Then, with the
probe oriented into the direction of flow, measure and record the
yaw angle, the differential pressures and the temperature at the
traverse point, after stable readings are achieved, in accordance
with sections 8.9.4 and 8.9.5. At the start of testing in each port
(i.e., after a probe has been inserted into the flue gas stream),
allow at least the response time to elapse before beginning to take
measurements at the first traverse point accessed from that port.
Provided that the probe is not removed from the flue gas stream,
measurements may be taken at subsequent traverse points accessed
from the same test port without waiting again for the response time
to elapse.
8.9.3 Yaw-nulling procedure. In preparation for yaw angle
determination, the probe must first be yaw nulled. After
positioning the probe at the appropriate traverse point, perform
the following procedures.
8.9.3.1 Rotate the probe until a null differential pressure
reading (the difference in pressures across the P2 and P3 pressure
ports is zero, i.e., P2 = P3) is indicated by the yaw angle
pressure gauge. Read and record the angle displayed by the
angle-measuring device.
8.9.3.2 Sign of the measured angle. The angle displayed on the
angle-measuring device is considered positive when the probe's
impact pressure port (as viewed from the “tail” end of the probe)
is oriented in a clockwise rotational position relative to the
stack or duct axis and is considered negative when the probe's
impact pressure port is oriented in a counterclockwise rotational
position (see Figure 2F-10).
8.9.4 Yaw angle determination. After performing the yaw-nulling
procedure in section 8.9.3, determine the yaw angle of flow
according to one of the following procedures. Special care must be
observed to take into account the signs of the recorded angle and
all offsets.
8.9.4.1 Direct-reading. If all rotational offsets are zero or if
the angle-measuring device rotational offset (RADO) determined in
section 8.3 exactly compensates for the scribe line rotational
offset (RSLO) determined in section 10.5, then the magnitude of the
yaw angle is equal to the displayed angle-measuring device reading
from section 8.9.3.1. The algebraic sign of the yaw angle is
determined in accordance with section 8.9.3.2.
Note:
Under certain circumstances (e.g., testing of horizontal ducts),
a 90° adjustment to the angle-measuring device readings may be
necessary to obtain the correct yaw angles.
8.9.4.2 Compensation for rotational offsets during data
reduction. When the angle-measuring device rotational offset does
not compensate for reference scribe line rotational offset, the
following procedure shall be used to determine the yaw angle:
(a) Enter the reading indicated by the angle-measuring device
from section 8.9.3.1.
(b) Associate the proper algebraic sign from section 8.9.3.2
with the reading in step (a).
(c) Subtract the reference scribe line rotational offset, RSLO,
from the reading in step (b).
(d) Subtract the angle-measuring device rotational offset, RADO,
if any, from the result obtained in step (c).
(e) The final result obtained in step (d) is the yaw angle of
flow.
Note:
It may be necessary to first apply a 90° adjustment to the
reading in step (a), in order to obtain the correct yaw angle.
8.9.4.3 Record the yaw angle measurements on a form similar to
Table 2F-3.
8.9.5 Velocity determination. Maintain the probe rotational
position established during the yaw angle determination. Then,
begin recording the pressure-measuring device readings for the
impact pressure (P1-P2) and pitch angle pressure (P4-P5). These
pressure measurements shall be taken over a sampling period of
sufficiently long duration to ensure representative readings at
each traverse point. If the pressure measurements are determined
from visual readings of the pressure device or display, allow
sufficient time to observe the pulsation in the readings to obtain
a sight-weighted average, which is then recorded manually. If an
automated data acquisition system (e.g., data logger,
computer-based data recorder, strip chart recorder) is used to
record the pressure measurements, obtain an integrated average of
all pressure readings at the traverse point. Stack or duct gas
temperature measurements shall be recorded, at a minimum, once at
each traverse point. Record all necessary data as shown in the
example field data form (Table 2F-3).
8.9.6 Alignment check. For manually operated probes, after the
required yaw angle and differential pressure and temperature
measurements have been made at each traverse point, verify (e.g.,
by visual inspection) that the yaw angle-measuring device has
remained in proper alignment with the reference scribe line or with
the rotational offset position established in section 8.3. If, for
a particular traverse point, the angle-measuring device is found to
be in proper alignment, proceed to the next traverse point;
otherwise, re-align the device and repeat the angle and
differential pressure measurements at the traverse point. In the
course of a traverse, if a mark used to properly align the
angle-measuring device (e.g., as described in section 18.1.1.1)
cannot be located, re-establish the alignment mark before
proceeding with the traverse.
8.10 Probe Plugging. Periodically check for plugging of the
pressure ports by observing the responses on pressure differential
readouts. Plugging causes erratic results or sluggish responses.
Rotate the probe to determine whether the readouts respond in the
expected direction. If plugging is detected, correct the problem
and repeat the affected measurements.
8.11 Static Pressure. Measure the static pressure in the stack
or duct using the equipment described in section 6.7.
8.11.1 If a Type DA or DAT probe is used for this measurement,
position the probe at or between any traverse point(s) and rotate
the probe until a null differential pressure reading is obtained at
P2-P3. Rotate the probe 90°. Disconnect the P2 pressure side of the
probe and read the pressure P1-Pbar and record as the static
pressure. (Note: The spherical probe, specified in section 6.1.2,
is unable to provide this measurement and shall not be used to take
static pressure measurements.)
8.11.2 If a Type S probe is used for this measurement, position
the probe at or between any traverse point(s) and rotate the probe
until a null differential pressure reading is obtained. Disconnect
the tubing from one of the pressure ports; read and record the ΔP.
For pressure devices with one-directional scales, if a deflection
in the positive direction is noted with the negative side
disconnected, then the static pressure is positive. Likewise, if a
deflection in the positive direction is noted with the positive
side disconnected, then the static pressure is negative.
8.12 Atmospheric Pressure. Determine the atmospheric pressure at
the sampling elevation during each test run following the procedure
described in section 2.5 of Method 2.
8.13 Molecular Weight. Determine the stack gas dry molecular
weight. For combustion processes or processes that emit essentially
CO2, O2, CO, and N2, use Method 3 or 3A. For processes emitting
essentially air, an analysis need not be conducted; use a dry
molecular weight of 29.0. Other methods may be used, if approved by
the Administrator.
8.14 Moisture. Determine the moisture content of the stack gas
using Method 4 or equivalent.
8.15 Data Recording and Calculations. Record all required data
on a form similar to Table 2F-3.
8.15.1 Selection of appropriate calibration curves. Choose the
appropriate pair of F1 and F2 versus pitch angle calibration
curves, created as described in section 10.6.
8.15.2 Pitch angle derivation. Use the appropriate calculation
procedures in section 12.2 to find the pitch angle ratios that are
applicable at each traverse point. Then, find the pitch angles
corresponding to these pitch angle ratios on the “F1 versus pitch
angle” curve for the probe.
8.15.3 Velocity calibration coefficient derivation. Use the
pitch angle obtained following the procedures described in section
8.15.2 to find the corresponding velocity calibration coefficients
from the “F2 versus pitch angle” calibration curve for the
probe.
8.15.4 Calculations. Calculate the axial velocity at each
traverse point using the equations presented in section 12.2 to
account for the yaw and pitch angles of flow. Calculate the test
run average stack gas velocity by finding the arithmetic average of
the point velocity results in accordance with sections 12.3 and
12.4, and calculate the stack gas volumetric flow rate in
accordance with section 12.5 or 12.6, as applicable.
9.0 Quality Control
9.1 Quality Control Activities. In conjunction with the yaw
angle determination and the pressure and temperature measurements
specified in section 8.9, the following quality control checks
should be performed.
9.1.1 Range of the differential pressure gauge. In accordance
with the specifications in section 6.4, ensure that the proper
differential pressure gauge is being used for the range of ΔP
values encountered. If it is necessary to change to a more
sensitive gauge, replace the gauge with a gauge calibrated
according to section 10.3.3, perform the leak check described in
section 8.4 and the zero check described in section 8.5, and repeat
the differential pressure and temperature readings at each traverse
point.
9.1.2 Horizontal stability check. For horizontal traverses of a
stack or duct, visually check that the probe shaft is maintained in
a horizontal position prior to taking a pressure reading.
Periodically, during a test run, the probe's horizontal stability
should be verified by placing a carpenter's level, a digital
inclinometer, or other angle-measuring device on the portion of the
probe sheath that extends outside of the test port. A comparable
check should be performed by automated systems.
10.0 Calibration
10.1 Wind Tunnel Qualification Checks. To qualify for use in
calibrating probes, a wind tunnel shall have the design features
specified in section 6.11 and satisfy the following qualification
criteria. The velocity pressure cross-check in section 10.1.1 and
axial flow verification in section 10.1.2 shall be performed before
the initial use of the wind tunnel and repeated immediately after
any alteration occurs in the wind tunnel's configuration, fans,
interior surfaces, straightening vanes, controls, or other
properties that could reasonably be expected to alter the flow
pattern or velocity stability in the tunnel. The owner or operator
of a wind tunnel used to calibrate probes according to this method
shall maintain records documenting that the wind tunnel meets the
requirements of sections 10.1.1 and 10.1.2 and shall provide these
records to the Administrator upon request.
10.1.1 Velocity pressure cross-check. To verify that the wind
tunnel produces the same velocity at the tested probe head as at
the calibration pitot tube impact port, perform the following
cross-check. Take three differential pressure measurements at the
fixed calibration pitot tube location, using the calibration pitot
tube specified in section 6.10, and take three measurements with
the calibration pitot tube at the wind tunnel calibration location,
as defined in section 3.20. Alternate the measurements between the
two positions. Perform this procedure at the lowest and highest
velocity settings at which the probes will be calibrated. Record
the values on a form similar to Table 2F-4. At each velocity
setting, the average velocity pressure obtained at the wind tunnel
calibration location shall be within ±2 percent or 2.5 mm H2O (0.01
in. H2O), whichever is less restrictive, of the average velocity
pressure obtained at the fixed calibration pitot tube location.
This comparative check shall be performed at 2.5-cm (1-in.), or
smaller, intervals across the full length, width, and depth (if
applicable) of the wind tunnel calibration location. If the
criteria are not met at every tested point, the wind tunnel
calibration location must be redefined, so that acceptable results
are obtained at every point. Include the results of the velocity
pressure cross-check in the calibration data section of the field
test report. (See section 16.1.4.)
10.1.2 Axial flow verification. The following procedures shall
be performed to demonstrate that there is fully developed axial
flow within the calibration location and at the calibration pitot
tube location. Two testing options are available to conduct this
check.
10.1.2.1 Using a calibrated 3-D probe. A 3-D probe that has been
previously calibrated in a wind tunnel with documented axial flow
(as defined in section 3.21) may be used to conduct this check.
Insert the calibrated 3-D probe into the wind tunnel test section
using the tested probe port. Following the procedures in sections
8.9 and 12.2 of this method, determine the yaw and pitch angles at
all the point(s) in the test section where the velocity pressure
cross-check, as specified in section 10.1.1, is performed. This
includes all the points in the calibration location and the point
where the calibration pitot tube will be located. Determine the yaw
and pitch angles at each point. Repeat these measurements at the
highest and lowest velocities at which the probes will be
calibrated. Record the values on a form similar to Table 2F-5. Each
measured yaw and pitch angle shall be within ±3° of 0°. Exceeding
the limits indicates unacceptable flow in the test section. Until
the problem is corrected and acceptable flow is verified by
repetition of this procedure, the wind tunnel shall not be used for
calibration of probes. Include the results of the axial flow
verification in the calibration data section of the field test
report. (See section 16.1.4.)
10.1.2.2 Using alternative probes. Axial flow verification may
be performed using an uncalibrated prism-shaped 3-D probe (e.g., DA
or DAT probe) or an uncalibrated wedge probe. (Figure 2F-11
illustrates a typical wedge probe.) This approach requires use of
two ports: the tested probe port and a second port located 90° from
the tested probe port. Each port shall provide access to all the
points within the wind tunnel test section where the velocity
pressure cross-check, as specified in section 10.1.1, is conducted.
The probe setup shall include establishing a reference yaw-null
position on the probe sheath to serve as the location for
installing the angle-measuring device. Physical design features of
the DA, DAT, and wedge probes are relied on to determine the
reference position. For the DA or DAT probe, this reference
position can be determined by setting a digital inclinometer on the
flat facet where the P1 pressure port is located and then
identifying the rotational position on the probe sheath where a
second angle-measuring device would give the same angle reading.
The reference position on a wedge probe shaft can be determined
either geometrically or by placing a digital inclinometer on each
side of the wedge and rotating the probe until equivalent readings
are obtained. With the latter approach, the reference position is
the rotational position on the probe sheath where an
angle-measuring device would give a reading of 0°. After installing
the angle-measuring device in the reference yaw-null position on
the probe sheath, determine the yaw angle from the tested port.
Repeat this measurement using the 90° offset port, which provides
the pitch angle of flow. Determine the yaw and pitch angles at all
the point(s) in the test section where the velocity pressure
cross-check, as specified in section 10.1.1, is performed. This
includes all the points in the wind tunnel calibration location and
the point where the calibration pitot tube will be located. Perform
this check at the highest and lowest velocities at which the probes
will be calibrated. Record the values on a form similar to Table
2F-5. Each measured yaw and pitch angle shall be within ±3° of 0°.
Exceeding the limits indicates unacceptable flow in the test
section. Until the problem is corrected and acceptable flow is
verified by repetition of this procedure, the wind tunnel shall not
be used for calibration of probes. Include the results in the probe
calibration report.
10.1.3 Wind tunnel audits.
10.1.3.1 Procedure. Upon the request of the Administrator, the
owner or operator of a wind tunnel shall calibrate a 3-D audit
probe in accordance with the procedures described in sections 10.3
through 10.6. The calibration shall be performed at two velocities
and over a pitch angle range that encompasses the velocities and
pitch angles typically used for this method at the facility. The
resulting calibration data and curves shall be submitted to the
Agency in an audit test report. These results shall be compared by
the Agency to reference calibrations of the audit probe at the same
velocity and pitch angle settings obtained at two different wind
tunnels.
10.1.3.2 Acceptance criteria. The audited tunnel's calibration
is acceptable if all of the following conditions are satisfied at
each velocity and pitch setting for the reference calibration
obtained from at least one of the wind tunnels. For pitch angle
settings between −15° and + 15°, no velocity calibration
coefficient (i.e., F2) may differ from the corresponding reference
value by more than 3 percent. For pitch angle settings outside of
this range (i.e., less than −15° and greater than + 15°), no
velocity calibration coefficient may differ by more than 5 percent
from the corresponding reference value. If the acceptance criteria
are not met, the audited wind tunnel shall not be used to calibrate
probes for use under this method until the problems are resolved
and acceptable results are obtained upon completion of a subsequent
audit.
10.2 Probe Inspection. Before each calibration of a 3-D probe,
carefully examine the physical condition of the probe head.
Particular attention shall be paid to the edges of the pressure
ports and the surfaces surrounding these ports. Any dents,
scratches, or asymmetries on the edges of the pressure ports and
any scratches or indentations on the surfaces surrounding the
pressure ports shall be noted because of the potential effect on
the probe's pressure readings. If the probe has been previously
calibrated, compare the current condition of the probe's pressure
ports and surfaces to the results of the inspection performed
during the probe's most recent wind tunnel calibration. Record the
results of this inspection on a form and in diagrams similar to
Table 2F-1. The information in Table 2F-1 will be used as the basis
for comparison during the probe head inspections performed before
each subsequent field use.
10.3 Pre-Calibration Procedures. Prior to calibration, a scribe
line shall have been placed on the probe in accordance with section
10.4. The yaw angle and velocity calibration procedures shall not
begin until the pre-test requirements in sections 10.3.1 through
10.3.4 have been met.
10.3.1 Perform the horizontal straightness check described in
section 8.2 on the probe assembly that will be calibrated in the
wind tunnel.
10.3.2 Perform a leak check in accordance with section 8.4.
10.3.3 Except as noted in section 10.3.3.3, calibrate all
differential pressure-measuring devices to be used in the probe
calibrations, using the following procedures. At a minimum,
calibrate these devices on each day that probe calibrations are
performed.
10.3.3.1 Procedure. Before each wind tunnel use, all
differential pressure-measuring devices shall be calibrated against
the reference device specified in section 6.4.3 using a common
pressure source. Perform the calibration at three reference
pressures representing 30, 60, and 90 percent of the full-scale
range of the pressure-measuring device being calibrated. For an
inclined-vertical manometer, perform separate calibrations on the
inclined and vertical portions of the measurement scale,
considering each portion of the scale to be a separate full-scale
range. [For example, for a manometer with a 0- to 2.5-cm H2O (0- to
1-in. H2O) inclined scale and a 2.5- to 12.7-cm H2O (1- to 5-in.
H2O) vertical scale, calibrate the inclined portion at 7.6, 15.2,
and 22.9 mm H2O (0.3, 0.6, and 0.9 in. H2O), and calibrate the
vertical portion at 3.8, 7.6, and 11.4 cm H2O (1.5, 3.0, and 4.5
in. H2O).] Alternatively, for the vertical portion of the scale,
use three evenly spaced reference pressures, one of which is equal
to or higher than the highest differential pressure expected in
field applications.
10.3.3.2 Acceptance criteria. At each pressure setting, the two
pressure readings made using the reference device and the
pressure-measuring device being calibrated shall agree to within ±2
percent of full scale of the device being calibrated or 0.5 mm H2O
(0.02 in. H2O), whichever is less restrictive. For an
inclined-vertical manometer, these requirements shall be met
separately using the respective full-scale upper limits of the
inclined and vertical portions of the scale. Differential
pressure-measuring devices not meeting the #2 percent of full scale
or 0.5 mm H2O (0.02 in. H2O) calibration requirement shall not be
used.
10.3.3.3 Exceptions. Any precision manometer that meets the
specifications for a reference device in section 6.4.3 and that is
not used for field testing does not require calibration, but must
be leveled and zeroed before each wind tunnel use. Any pressure
device used exclusively for yaw nulling does not require
calibration, but shall be checked for responsiveness to rotation of
the probe prior to each wind tunnel use.
10.3.4 Calibrate digital inclinometers on each day of wind
tunnel or field testing (prior to beginning testing) using the
following procedures. Calibrate the inclinometer according to the
manufacturer's calibration procedures. In addition, use a
triangular block (illustrated in Figure 2F-12) with a known angle,
θ independently determined using a protractor or equivalent device,
between two adjacent sides to verify the inclinometer readings.
Note:
If other angle-measuring devices meeting the provisions of
section 6.2.3 are used in place of a digital inclinometer,
comparable calibration procedures shall be performed on such
devices.)
Secure the triangular block in a fixed position. Place the
inclinometer on one side of the block (side A) to measure the angle
of inclination (R1). Repeat this measurement on the adjacent side
of the block (side B) using the inclinometer to obtain a second
angle reading (R2). The difference of the sum of the two readings
from 180° (i.e., 180° −R1 −R2) shall be within ±2° of the known
angle, Θ
10.4 Placement of Reference Scribe Line. Prior to the first
calibration of a probe, a line shall be permanently inscribed on
the main probe sheath to serve as a reference mark for determining
yaw angles. Annex C in section 18 of this method gives a guideline
for placement of the reference scribe line.
10.4.1 This reference scribe line shall meet the specifications
in sections 6.1.6.1 and 6.1.6.3 of this method. To verify that the
alignment specification in section 6.1.6.3 is met, secure the probe
in a horizontal position and measure the rotational angle of each
scribe line and scribe line segment using an angle-measuring device
that meets the specifications in section 6.2.1 or 6.2.3. For any
scribe line that is longer than 30.5 cm (12 in.), check the line's
rotational position at 30.5-cm (12-in.) intervals. For each line
segment that is 30.5 cm (12 in.) or less in length, check the
rotational position at the two endpoints of the segment. To meet
the alignment specification in section 6.1.6.3, the minimum and
maximum of all of the rotational angles that are measured along the
full length of the main probe must not differ by more than 2°.
Note:
A short reference scribe line segment [e.g., 15.2 cm (6 in.) or
less in length] meeting the alignment specifications in section
6.1.6.3 is fully acceptable under this method. See section 18.1.1.1
of Annex A for an example of a probe marking procedure, suitable
for use with a short reference scribe line.
10.4.2 The scribe line should be placed on the probe first and
then its offset from the yaw-null position established (as
specified in section 10.5). The rotational position of the
reference scribe line relative to the yaw-null position of the
probe, as determined by the yaw angle calibration procedure in
section 10.5, is defined as the reference scribe line rotational
offset, RSLO. The reference scribe line rotational offset shall be
recorded and retained as part of the probe's calibration
record.
10.4.3 Scribe line for automated probes. A scribe line may not
be necessary for an automated probe system if a reference
rotational position of the probe is built into the probe system
design. For such systems, a “flat” (or comparable, clearly
identifiable physical characteristic) should be provided on the
probe casing or flange plate to ensure that the reference position
of the probe assembly remains in a vertical or horizontal position.
The rotational offset of the flat (or comparable, clearly
identifiable physical characteristic) needed to orient the
reference position of the probe assembly shall be recorded and
maintained as part of the automated probe system's
specifications.
10.5 Yaw Angle Calibration Procedure. For each probe used to
measure yaw angles with this method, a calibration procedure shall
be performed in a wind tunnel meeting the specifications in section
10.1 to determine the rotational position of the reference scribe
line relative to the probe's yaw-null position. This procedure
shall be performed on the main probe with all devices that will be
attached to the main probe in the field [such as thermocouples or
resistance temperature detectors (RTDs)] that may affect the flow
around the probe head. Probe shaft extensions that do not affect
flow around the probe head need not be attached during calibration.
At a minimum, this procedure shall include the following steps.
10.5.1 Align and lock the angle-measuring device on the
reference scribe line. If a marking procedure (such as that
described in section 18.1.1.1) is used, align the angle-measuring
device on a mark within ±1° of the rotational position of the
reference scribe line. Lock the angle-measuring device onto the
probe sheath at this position.
10.5.2 Zero the pressure-measuring device used for yaw
nulling.
10.5.3 Insert the probe assembly into the wind tunnel through
the entry port, positioning the probe's impact port at the
calibration location. Check the responsiveness of the
pressure-measurement device to probe rotation, taking corrective
action if the response is unacceptable.
10.5.4 Ensure that the probe is in a horizontal position, using
a carpenter's level.
10.5.5 Rotate the probe either clockwise or counterclockwise
until a yaw null (P2 = P3) is obtained.
10.5.6 Use the reading displayed by the angle-measuring device
at the yaw-null position to determine the magnitude of the
reference scribe line rotational offset, RSLO, as defined in
section 3.15. Annex D in section 18 of this method provides a
recommended procedure for determining the magnitude of RSLO with a
digital inclinometer and a second procedure for determining the
magnitude of RSLO with a protractor wheel and pointer device. Table
2F-6 presents an example data form and Table 2F-7 is a look-up
table with the recommended procedure. Procedures other than those
recommended in Annex D in section 18 may be used, if they can
determine RSLO to within ±1° and are explained in detail in the
field test report. The algebraic sign of RSLO will either be
positive, if the rotational position of the reference scribe line
(as viewed from the “tail” end of the probe) is clockwise, or
negative, if counterclockwise with respect to the probe's yaw-null
position. (This is illustrated in Figure 2F-13.)
10.5.7 The steps in sections 10.5.3 through 10.5.6 shall be
performed twice at each of the velocities at which the probe will
be calibrated (in accordance with section 10.6). Record the values
of RSLO.
10.5.8 The average of all of the RSLO values shall be documented
as the reference scribe line rotational offset for the probe.
10.5.9 Use of reference scribe line offset. The reference scribe
line rotational offset shall be used to determine the yaw angle of
flow in accordance with section 8.9.4.
10.6 Pitch Angle and Velocity Pressure Calibrations. Use the
procedures in sections 10.6.1 through 10.6.16 to generate an
appropriate set (or sets) of pitch angle and velocity pressure
calibration curves for each probe. The calibration procedure shall
be performed on the main probe and all devices that will be
attached to the main probe in the field (e.g., thermocouple or
RTDs) that may affect the flow around the probe head. Probe shaft
extensions that do not affect flow around the probe head need not
be attached during calibration. (Note: If a sampling nozzle is part
of the assembly, a wind tunnel demonstration shall be performed
that shows the probe's ability to measure velocity and yaw null is
not impaired when the nozzle is drawing a sample.) The calibration
procedure involves generating two calibration curves, F1 versus
pitch angle and F2 versus pitch angle. To generate these two
curves, F1 and F2 shall be derived using Equations 2F-1 and 2F-2,
below. Table 2F-8 provides an example wind tunnel calibration data
sheet, used to log the measurements needed to derive these two
calibration curves.
10.6.1 Calibration velocities. The tester may calibrate the
probe at two nominal wind tunnel velocity settings of 18.3 m/sec
and 27.4 m/sec (60 ft/sec and 90 ft/sec) and average the results of
these calibrations, as described in section 10.6.16.1, in order to
generate a set of calibration curves. If this option is selected,
this single set of calibration curves may be used for all field
applications over the entire velocity range allowed by the method.
Alternatively, the tester may customize the probe calibration for a
particular field test application (or for a series of
applications), based on the expected average velocity(ies) at the
test site(s). If this option is selected, generate each set of
calibration curves by calibrating the probe at two nominal wind
tunnel velocity settings, at least one of which is greater than or
equal to the expected average velocity(ies) for the field
application(s), and average the results as described in section
10.6.16.1. Whichever calibration option is selected, the probe
calibration coefficients (F2 values) obtained at the two nominal
calibration velocities shall, for the same pitch angle setting,
meet the conditions specified in section 10.6.16.
10.6.2 Pitch angle calibration curve (F1 versus pitch angle).
The pitch angle calibration involves generating a calibration curve
of calculated F1 values versus tested pitch angles, where F1 is the
ratio of the pitch pressure to the velocity pressure, i.e.,
See
Figure 2F-14 for an example F1 versus pitch angle calibration
curve.
10.6.3 Velocity calibration curve (F2 versus pitch angle). The
velocity calibration involves generating a calibration curve of the
3-D probe's F2 coefficient against the tested pitch angles,
where
and Cp =
calibration pitot tube coefficient, and ΔPstd = velocity pressure
from the calibration pitot tube. See Figure 2F-15 for an example F2
versus pitch angle calibration curve.
10.6.4 Connect the tested probe and calibration pitot probe to
their respective pressure-measuring devices. Zero the
pressure-measuring devices. Inspect and leak-check all pitot lines;
repair or replace, if necessary. Turn on the fan, and allow the
wind tunnel air flow to stabilize at the first of the two selected
nominal velocity settings.
10.6.5 Position the calibration pitot tube at its measurement
location (determined as outlined in section 6.11.4.3), and align
the tube so that its tip is pointed directly into the flow. Ensure
that the entry port surrounding the tube is properly sealed. The
calibration pitot tube may either remain in the wind tunnel
throughout the calibration, or be removed from the wind tunnel
while measurements are taken with the probe being calibrated.
10.6.6 Set up the pitch protractor plate on the tested probe's
entry port to establish the pitch angle positions of the probe to
within ±2°.
10.6.7 Check the zero setting of each pressure-measuring
device.
10.6.8 Insert the tested probe into the wind tunnel and align it
so that its P1 pressure port is pointed directly into the flow and
is positioned within the calibration location (as defined in
section 3.20). Secure the probe at the 0° pitch angle position.
Ensure that the entry port surrounding the probe is properly
sealed.
10.6.9 Read the differential pressure from the calibration pitot
tube (ΔPstd), and record its value. Read the barometric pressure to
within ±2.5 mm Hg (±0.1 in. Hg) and the temperature in the wind
tunnel to within 0.6 °C (1 °F). Record these values on a data form
similar to Table 2F-8.
10.6.10 After the tested probe's differential pressure gauges
have had sufficient time to stabilize, yaw null the probe, then
obtain differential pressure readings for (P1-P2) and (P4-P5).
Record the yaw angle and differential pressure readings. After
taking these readings, ensure that the tested probe has remained at
the yaw-null position.
10.6.11 Either take paired differential pressure measurements
with both the calibration pitot tube and tested probe (according to
sections 10.6.9 and 10.6.10) or take readings only with the tested
probe (according to section 10.6.10) in 5° increments over the
pitch-angle range for which the probe is to be calibrated. The
calibration pitch-angle range shall be symmetric around 0° and
shall exceed the largest pitch angle expected in the field by 5°.
At a minimum, probes shall be calibrated over the range of −15° to
+ 15°. If paired calibration pitot tube and tested probe
measurements are not taken at each pitch angle setting, the
differential pressure from the calibration pitot tube shall be
read, at a minimum, before taking the tested probe's differential
pressure reading at the first pitch angle setting and after taking
the tested probe's differential pressure readings at the last pitch
angle setting in each replicate.
10.6.12 Perform a second replicate of the procedures in sections
10.6.5 through 10.6.11 at the same nominal velocity setting.
10.6.13 For each replicate, calculate the F1 and F2 values at
each pitch angle. At each pitch angle, calculate the percent
difference between the two F2 values using Equation 2F-3.
If the percent difference is less than or equal to 2 percent,
calculate an average F1 value and an average F2 value at that pitch
angle. If the percent difference is greater than 2 percent and less
than or equal to 5 percent, perform a third repetition at that
angle and calculate an average F1 value and an average F2 value
using all three repetitions. If the percent difference is greater
than 5 percent, perform four additional repetitions at that angle
and calculate an average F1 value and an average F2 value using all
six repetitions. When additional repetitions are required at any
pitch angle, move the probe by at least 5° and then return to the
specified pitch angle before taking the next measurement. Record
the average values on a form similar to Table 2F-9.
10.6.14 Repeat the calibration procedures in sections 10.6.5
through 10.6.13 at the second selected nominal wind tunnel velocity
setting.
10.6.15 Velocity drift check. The following check shall be
performed, except when paired calibration pitot tube and tested
probe pressure measurements are taken at each pitch angle setting.
At each velocity setting, calculate the percent difference between
consecutive differential pressure measurements made with the
calibration pitot tube. If a measurement differs from the previous
measurement by more than 2 percent or 0.25 mm H2O (0.01 in. H2O),
whichever is less restrictive, the calibration data collected
between these calibration pitot tube measurements may not be used,
and the measurements shall be repeated.
10.6.16 Compare the averaged F2 coefficients obtained from the
calibrations at the two selected nominal velocities, as follows. At
each pitch angle setting, use Equation 2F-3 to calculate the
difference between the corresponding average F2 values at the two
calibration velocities. At each pitch angle in the −15° to + 15°
range, the percent difference between the average F2 values shall
not exceed 3.0 percent. For pitch angles outside this range (i.e.,
less than −15°0 and greater than + 15°), the percent difference
shall not exceed 5.0 percent.
10.6.16.1 If the applicable specification in section 10.6.16 is
met at each pitch angle setting, average the results obtained at
the two nominal calibration velocities to produce a calibration
record of F1 and F2 at each pitch angle tested. Record these values
on a form similar to Table 2F-9. From these values, generate one
calibration curve representing F1 versus pitch angle and a second
curve representing F2 versus pitch angle. Computer spreadsheet
programs may be used to graph the calibration data and to develop
polynomial equations that can be used to calculate pitch angles and
axial velocities.
10.6.16.2 If the applicable specification in section 10.6.16 is
exceeded at any pitch angle setting, the probe shall not be used
unless: (1) the calibration is repeated at that pitch angle and
acceptable results are obtained or (2) values of F1 and F2 are
obtained at two nominal velocities for which the specifications in
section 10.6.16 are met across the entire pitch angle range.
10.7 Recalibration. Recalibrate the probe using the procedures
in section 10 either within 12 months of its first field use after
its most recent calibration or after 10 field tests (as defined in
section 3.4), whichever occurs later. In addition, whenever there
is visible damage to the 3-D head, the probe shall be recalibrated
before it is used again.
10.8 Calibration of pressure-measuring devices used in field
tests. Before its initial use in a field test, calibrate each
pressure-measuring device (except those used exclusively for yaw
nulling) using the three-point calibration procedure described in
section 10.3.3. The device shall be recalibrated according to the
procedure in section 10.3.3 no later than 90 days after its first
field use following its most recent calibration. At the discretion
of the tester, more frequent calibrations (e.g., after a field
test) may be performed. No adjustments, other than adjustments to
the zero setting, shall be made to the device between
calibrations.
10.8.1 Post-test calibration check. A single-point calibration
check shall be performed on each pressure-measuring device after
completion of each field test. At the discretion of the tester,
more frequent single-point calibration checks (e.g., after one or
more field test runs) may be performed. It is recommended that the
post-test check be performed before leaving the field test site.
The check shall be performed at a pressure between 50 and 90
percent of full scale by taking a common pressure reading with the
tested device and a reference pressure-measuring device (as
described in section 6.4.4) or by challenging the tested device
with a reference pressure source (as described in section 6.4.4) or
by performing an equivalent check using a reference device approved
by the Administrator.
10.8.2 Acceptance criterion. At the selected pressure setting,
the pressure readings made using the reference device and the
tested device shall agree to within 3 percent of full scale of the
tested device or 0.8 mm H2O (0.03 in. H2O), whichever is less
restrictive. If this specification is met, the test data collected
during the field test are valid. If the specification is not met,
all test data collected since the last successful calibration or
calibration check are invalid and shall be repeated using a
pressure-measuring device with a current, valid calibration. Any
device that fails the calibration check shall not be used in a
field test until a successful recalibration is performed according
to the procedures in section 10.3.3.
10.9 Temperature Gauges. Same as Method 2, section 4.3. The
alternative thermocouple calibration procedures outlined in
Emission Measurement Center (EMC) Approved Alternative Method
(ALT-011) “Alternative Method 2 Thermocouple Calibration Procedure”
may be performed. Temperature gauges shall be calibrated no more
than 30 days prior to the start of a field test or series of field
tests and recalibrated no more than 30 days after completion of a
field test or series of field tests.
10.10 Barometer. Same as Method 2, section 4.4. The barometer
shall be calibrated no more than 30 days prior to the start of a
field test or series of field tests.
11.0 Analytical Procedure
Sample collection and analysis are concurrent for this method
(see section 8.0).
12.0 Data Analysis and Calculations
These calculations use the measured yaw angle, derived pitch
angle, and the differential pressure and temperature measurements
at individual traverse points to derive the axial flue gas velocity
(va(i)) at each of those points. The axial velocity values at all
traverse points that comprise a full stack or duct traverse are
then averaged to obtain the average axial flue gas velocity (va
(avg)). Round off figures only in the final calculation of reported
values.
12.1 Nomenclature
A = Cross-sectional area of stack or duct, m 2 (ft 2). Bws = Water
vapor in the gas stream (from Method 4 or alternative), proportion
by volume. Kp Conversion factor (a constant), for the metric
system, and for the English
system. Md = Molecular weight of stack or duct gas, dry basis (see
section 8.13), g/g-mole (lb/lb-mole). Ms = Molecular weight of
stack or duct gas, wet basis, g/g-mole (lb/lb-mole). Pbar = Barometric
pressure at measurement site, mm Hg (in. Hg). Pg = Stack or duct
static pressure, mm H2O (in. H2O). Ps = Absolute stack or duct
pressure, mm Hg (in. Hg), Pstd = Standard
absolute pressure, 760 mm Hg (29.92 in. Hg). 13.6 = Conversion from
mm H2O (in. H2O) to mm Hg (in. Hg). Qsd = Average dry-basis
volumetric stack or duct gas flow rate corrected to standard
conditions, dscm/hr (dscf/hr). Qsw = Average wet-basis volumetric
stack or duct gas flow rate corrected to standard conditions,
wscm/hr (wscf/hr). Ts(avg) = Average absolute stack or duct gas
temperature across all traverse points. ts(i) = Stack or duct gas
temperature, C (F), at traverse point i. Ts(i) = Absolute stack or
duct gas temperature, K (R), at traverse point i, for the metric
system, and for the English
system. Tstd = Standard absolute temperature, 293 °K (528 °R).
F1(i) = Pitch angle ratio, applicable at traverse point i,
dimensionless. F2(i) = 3-D probe velocity calibration coefficient,
applicable at traverse point i, dimensionless. (P4-P5)i = Pitch
differential pressure of stack or duct gas flow, mm H2O (in. H2O),
at traverse point i. (P1-P2)i = Velocity head (differential
pressure) of stack or duct gas flow, mm H2O (in. H2O), at traverse
point i. va(i) = Reported stack or duct gas axial velocity, m/sec
(ft/sec), at traverse point i. va(avg) = Average stack or duct gas
axial velocity, m/sec (ft/sec), across all traverse points. 3,600 =
Conversion factor, sec/hr. 18.0 = Molecular weight of water,
g/g-mole (lb/lb-mole). θy(i) = Yaw angle, degrees, at traverse
point i. θp(i) = Pitch angle, degrees, at traverse point i. n =
Number of traverse points.
12.2 Traverse Point Velocity Calculations. Perform the following
calculations from the measurements obtained at each traverse
point.
12.2.1 Selection of calibration curves. Select calibration
curves as described in section 10.6.1.
12.2.2 Traverse point pitch angle ratio. Use Equation 2F-1, as
described in section 10.6.2, to calculate the pitch angle ratio,
F1(i), at each traverse point.
12.2.3 Pitch angle. Use the pitch angle ratio, F1(i), to derive
the pitch angle, θp(i), at traverse point i from the F1 versus
pitch angle calibration curve generated under section
10.6.16.1.
12.2.4 Velocity calibration coefficient. Use the pitch angle,
θp(i), to obtain the probe velocity calibration coefficient, F2(i),
at traverse point i from the “velocity pressure calibration curve,”
i.e., the F2 versus pitch angle calibration curve generated under
section 10.6.16.1.
12.2.5 Axial velocity. Use the following equation to calculate
the axial velocity, va(i), from the differential pressure (P1-P2)i
and yaw angle, θy(i), measured at traverse point i and the
previously calculated values for the velocity calibration
coefficient, F2(i), absolute stack or duct standard temperature,
Ts(i), absolute stack or duct pressure, Ps, molecular weight, Ms,
and pitch angle, “θp(i).
12.2.6 Handling multiple measurements at a traverse point. For
pressure or temperature devices that take multiple measurements at
a traverse point, the multiple measurements (or where applicable,
their square roots) may first be averaged and the resulting average
values used in the equations above. Alternatively, the individual
measurements may be used in the equations above and the resulting
multiple calculated values may then be averaged to obtain a single
traverse point value. With either approach, all of the individual
measurements recorded at a traverse point must be used in
calculating the applicable traverse point value.
12.3 Average Axial Velocity in Stack or Duct. Use the reported
traverse point axial velocity in the following equation.
12.4 Acceptability of Results. The test results are acceptable
and the calculated value of va(avg) may be reported as the average
axial velocity for the test run if the conditions in either section
12.4.1 or 12.4.2 are met.
12.4.1 The calibration curves were generated at nominal
velocities of 18.3 m/sec and 27.4 m/sec (60 ft/sec and 90
ft/sec).
12.4.2 The calibration curves were generated at nominal
velocities other than 18.3 m/sec and 27.4 m/sec (60 ft/sec and 90
ft/sec), and the value of va(avg) obtained using Equation 2F-9 is
less than or equal to at least one of the nominal velocities used
to derive the F1 and F2 calibration curves.
12.4.3 If the conditions in neither section 12.4.1 nor section
12.4.2 are met, the test results obtained in Equation 2F-9 are not
acceptable, and the steps in sections 12.2 and 12.3 must be
repeated using a set of F1 and F2 calibration curves that satisfies
the conditions specified in section 12.4.1 or 12.4.2.
12.5 Average Gas Wet Volumetric Flow Rate in Stack or Duct. Use
the following equation to compute the average volumetric flow rate
on a wet basis.
12.6 Average Gas Dry Volumetric Flow Rate in Stack or Duct. Use
the following equation to compute the average volumetric flow rate
on a dry basis.
16.1 Field Test Reports. Field test reports shall be submitted
to the Agency according to applicable regulatory requirements.
Field test reports should, at a minimum, include the following
elements.
16.1.1 Description of the source. This should include the name
and location of the test site, descriptions of the process tested,
a description of the combustion source, an accurate diagram of
stack or duct cross-sectional area at the test site showing the
dimensions of the stack or duct, the location of the test ports,
and traverse point locations and identification numbers or codes.
It should also include a description and diagram of the stack or
duct layout, showing the distance of the test location from the
nearest upstream and downstream disturbances and all structural
elements (including breachings, baffles, fans, straighteners, etc.)
affecting the flow pattern. If the source and test location
descriptions have been previously submitted to the Agency in a
document (e.g., a monitoring plan or test plan), referencing the
document in lieu of including this information in the field test
report is acceptable.
16.1.2 Field test procedures. These should include a description
of test equipment and test procedures. Testing conventions, such as
traverse point numbering and measurement sequence (e.g., sampling
from center to wall, or wall to center), should be clearly stated.
Test port identification and directional reference for each test
port should be included on the appropriate field test data
sheets.
16.1.3 Field test data.
16.1.3.1 Summary of results. This summary should include the
dates and times of testing and the average axial gas velocity and
the average flue gas volumetric flow results for each run and
tested condition.
16.1.3.2 Test data. The following values for each traverse point
should be recorded and reported:
(a) P1-P2 and P4-P5 differential pressures
(b) Stack or duct gas temperature at traverse point i
(ts(i))
(c) Absolute stack or duct gas temperature at traverse point i
(Ts(i))
(d) Yaw angle at each traverse point i (θy(i))
(e) Pitch angle at each traverse point i (θp(i))
(f) Stack or duct gas axial velocity at traverse point i
(va(i))
16.1.3.3 The following values should be reported once per
run:
(a) Water vapor in the gas stream (from Method 4 or
alternative), proportion by volume (Bws), measured at the frequency
specified in the applicable regulation
(b) Molecular weight of stack or duct gas, dry basis (Md)
(c) Molecular weight of stack or duct gas, wet basis (Ms)
(d) Stack or duct static pressure (Pg)
(e) Absolute stack or duct pressure (Ps)
(f) Carbon dioxide concentration in the flue gas, dry basis (
0/0d CO2)
(g) Oxygen concentration in the flue gas, dry basis ( 0/0d
O2)
(h) Average axial stack or duct gas velocity (va(avg)) across
all traverse points
(i) Gas volumetric flow rate corrected to standard conditions,
dry or wet basis as required by the applicable regulation (Qsd or
Qsw)
16.1.3.4 The following should be reported once per complete set of
test runs:
(a) Cross-sectional area of stack or duct at the test location
(A)
(b) Measurement system response time (sec)
(c) Barometric pressure at measurement site (Pbar)
16.1.4 Calibration data. The field test report should include
calibration data for all probes and test equipment used in the
field test. At a minimum, the probe calibration data reported to
the Agency should include the following:
(a) Date of calibration
(b) Probe type
(c) Probe identification number(s) or code(s)
(d) Probe inspection sheets
(e) Pressure measurements and intermediate calculations of F1
and F2 at each pitch angle used to obtain calibration curves in
accordance with section 10.6 of this method
(f) Calibration curves (in graphic or equation format) obtained
in accordance with sections 10.6.11 of this method
(g) Description and diagram of wind tunnel used for the
calibration, including dimensions of cross-sectional area and
position and size of the test section
(h) Documentation of wind tunnel qualification tests performed
in accordance with section 10.1 of this method
16.1.5 Quality Assurance. Specific quality assurance and quality
control procedures used during the test should be described.
17.0 Bibliography
(1) 40 CFR Part 60, Appendix A, Method 1 - Sample and velocity
traverses for stationary sources.
(2) 40 CFR Part 60, Appendix A, Method 2H - Determination of
stack gas velocity taking into account velocity decay near the
stack wall.
(3) 40 CFR Part 60, Appendix A, Method 2 - Determination of
stack gas velocity and volumetric flow rate (Type S pitot
tube).
(4) 40 CFR Part 60, Appendix A, Method 3 - Gas analysis for
carbon dioxide, oxygen, excess air, and dry molecular weight.
(5) 40 CFR Part 60, Appendix A, Method 3A - Determination of
oxygen and carbon dioxide concentrations in emissions from
stationary sources (instrumental analyzer procedure).
(6) 40 CFR Part 60, Appendix A, Method 4 - Determination of
moisture content in stack gases.
(7) Emission Measurement Center (EMC) Approved Alternative
Method (ALT-011) “Alternative Method 2 Thermocouple Calibration
Procedure.”
(8) Electric Power Research Institute, Interim Report EPRI
TR-106698, “Flue Gas Flow Rate Measurement Errors,” June 1996.
(9) Electric Power Research Institute, Final Report EPRI
TR-108110, “Evaluation of Heat Rate Discrepancy from Continuous
Emission Monitoring Systems,” August 1997.
(10) Fossil Energy Research Corporation, Final Report, “Velocity
Probe Tests in Non-axial Flow Fields,” November 1998, Prepared for
the U.S. Environmental Protection Agency.
(11) Fossil Energy Research Corporation, “Additional Swirl
Tunnel Tests: E-DAT and T-DAT Probes,” February 24, 1999, Technical
Memorandum Prepared for U.S. Environmental Protection Agency, P.O.
No. 7W-1193-NALX.
(12) Massachusetts Institute of Technology, Report WBWT-TR-1317,
“Calibration of Eight Wind Speed Probes Over a Reynolds Number
Range of 46,000 to 725,000 Per Foot, Text and Summary Plots,” Plus
appendices, October 15, 1998, Prepared for The Cadmus Group,
Inc.
(13) National Institute of Standards and Technology, Special
Publication 250, “NIST Calibration Services Users Guide 1991,”
Revised October 1991, U.S. Department of Commerce, p. 2.
(14) National Institute of Standards and Technology, 1998,
“Report of Special Test of Air Speed Instrumentation, Four Prandtl
Probes, Four S-Type Probes, Four French Probes, Four Modified Kiel
Probes,” Prepared for the U.S. Environmental Protection Agency
under IAG #DW13938432-01-0.
(15) National Institute of Standards and Technology, 1998,
“Report of Special Test of Air Speed Instrumentation, Five
Autoprobes,” Prepared for the U.S. Environmental Protection Agency
under IAG #DW13938432-01-0.
(16) National Institute of Standards and Technology, 1998,
“Report of Special Test of Air Speed Instrumentation, Eight
Spherical Probes,” Prepared for the U.S. Environmental Protection
Agency under IAG #DW13938432-01-0.
(17) National Institute of Standards and Technology, 1998,
“Report of Special Test of Air Speed Instrumentation, Four DAT
Probes,” Prepared for the U.S. Environmental Protection Agency
under IAG #DW13938432-01-0.
(18) Norfleet, S.K., “An Evaluation of Wall Effects on Stack
Flow Velocities and Related Overestimation Bias in EPA's Stack Flow
Reference Methods,” EPRI CEMS User's Group Meeting, New Orleans,
Louisiana, May 13-15, 1998.
(19) Page, J.J., E.A. Potts, and R.T. Shigehara, “3-D Pitot Tube
Calibration Study,” EPA Contract No. 68-D1-0009, Work Assignment
No. I-121, March 11, 1993.
(20) Shigehara, R.T., W.F. Todd, and W.S. Smith, “Significance
of Errors in Stack Sampling Measurements,” Presented at the Annual
Meeting of the Air Pollution Control Association, St. Louis,
Missouri, June 14-19, 1970.
(21) The Cadmus Group, Inc., May 1999, “EPA Flow Reference
Method Testing and Analysis: Findings Report,”
EPA/430-R-99-009.
(22) The Cadmus Group, Inc., 1998, “EPA Flow Reference Method
Testing and Analysis: Data Report, Texas Utilities, DeCordova Steam
Electric Station, Volume I: Test Description and Appendix A (Data
Distribution Package),” EPA/430-R-98-015a.
(23) The Cadmus Group, Inc., 1998, “EPA Flow Reference Method
Testing and Analysis: Data Report, Texas Utilities, Lake Hubbard
Steam Electric Station, Volume I: Test Description and Appendix A
(Data Distribution Package),” EPA/430-R-98-017a.
(24) The Cadmus Group, Inc., 1998, “EPA Flow Reference Method
Testing and Analysis: Data Report, Pennsylvania Electric Co.,
G.P.U. Genco Homer City Station: Unit 1, Volume I: Test Description
and Appendix A (Data Distribution Package),” EPA/430-R-98-018a.
(25) The Cadmus Group, Inc., 1997, “EPA Flow Reference Method
Testing and Analysis: Wind Tunnel Experimental Results,”
EPA/430-R-97-013.
18.0 Annexes
Annex A, C, and D describe recommended procedures for meeting
certain provisions in sections 8.3, 10.4, and 10.5 of this method.
Annex B describes procedures to be followed when using the
protractor wheel and pointer assembly to measure yaw angles, as
provided under section 8.9.1.
18.1 Annex A - Rotational Position Check. The following are
recommended procedures that may be used to satisfy the rotational
position check requirements of section 8.3 of this method and to
determine the angle-measuring device rotational offset RADO.
18.1.1 Rotational position check with probe outside stack. Where
physical constraints at the sampling location allow full assembly
of the probe outside the stack and insertion into the test port,
the following procedures should be performed before the start of
testing. Two angle-measuring devices that meet the specifications
in section 6.2.1 or 6.2.3 are required for the rotational position
check. An angle measuring device whose position can be
independently adjusted (e.g., by means of a set screw) after being
locked into position on the probe sheath shall not be used for this
check unless the independent adjustment is set so that the device
performs exactly like a device without the capability for
independent adjustment. That is, when aligned on the probe such a
device must give the same reading as a device that does not have
the capability of being independently adjusted. With the fully
assembled probe (including probe shaft extensions, if any) secured
in a horizontal position, affix one yaw angle-measuring device to
the probe sheath and lock it into position on the reference scribe
line specified in section 6.1.6.1. Position the second
angle-measuring device using the procedure in section 18.1.1.1 or
18.1.1.2.
18.1.1.1 Marking procedure. The procedures in this section
should be performed at each location on the fully assembled probe
where the yaw angle-measuring device will be mounted during the
velocity traverse. Place the second yaw angle-measuring device on
the main probe sheath (or extension) at the position where a yaw
angle will be measured during the velocity traverse. Adjust the
position of the second angle-measuring device until it indicates
the same angle (±1°) as the reference device, and affix the second
device to the probe sheath (or extension). Record the angles
indicated by the two angle-measuring devices on a form similar to
Table 2F-2. In this position, the second angle-measuring device is
considered to be properly positioned for yaw angle measurement.
Make a mark, no wider than 1.6 mm (1/16 in.), on the probe sheath
(or extension), such that the yaw angle-measuring device can be
re-affixed at this same properly aligned position during the
velocity traverse.
18.1.1.2 Procedure for probe extensions with scribe lines. If,
during a velocity traverse the angle-measuring device will be
affixed to a probe extension having a scribe line as specified in
section 6.1.6.2, the following procedure may be used to align the
extension's scribe line with the reference scribe line instead of
marking the extension as described in section 18.1.1.1. Attach the
probe extension to the main probe. Align and lock the second
angle-measuring device on the probe extension's scribe line. Then,
rotate the extension until both measuring devices indicate the same
angle (±1°). Lock the extension at this rotational position. Record
the angles indicated by the two angle-measuring devices on a form
similar to Table 2F-2. An angle-measuring device may be aligned at
any position on this scribe line during the velocity traverse, if
the scribe line meets the alignment specification in section
6.1.6.3.
18.1.1.3 Post-test rotational position check. If the fully
assembled probe includes one or more extensions, the following
check should be performed immediately after the completion of a
velocity traverse. At the discretion of the tester, additional
checks may be conducted after completion of testing at any sample
port. Without altering the alignment of any of the components of
the probe assembly used in the velocity traverse, secure the fully
assembled probe in a horizontal position. Affix an angle-measuring
device at the reference scribe line specified in section 6.1.6.1.
Use the other angle-measuring device to check the angle at each
location where the device was checked prior to testing. Record the
readings from the two angle-measuring devices.
18.1.2 Rotational position check with probe in stack. This
section applies only to probes that, due to physical constraints,
cannot be inserted into the test port as fully assembled with all
necessary extensions needed to reach the inner-most traverse
point(s).
18.1.2.1 Perform the out-of-stack procedure in section 18.1.1 on
the main probe and any attached extensions that will be initially
inserted into the test port.
18.1.2.2 Use the following procedures to perform additional
rotational position check(s) with the probe in the stack, each time
a probe extension is added. Two angle-measuring devices are
required. The first of these is the device that was used to measure
yaw angles at the preceding traverse point, left in its properly
aligned measurement position. The second angle-measuring device is
positioned on the added probe extension. Use the applicable
procedures in section 18.1.1.1 or 18.1.1.2 to align, adjust, lock,
and mark (if necessary) the position of the second angle-measuring
device to within ±1° of the first device. Record the readings of
the two devices on a form similar to Table 2F-2.
18.1.2.3 The procedure in section 18.1.2.2 should be performed
at the first port where measurements are taken. The procedure
should be repeated each time a probe extension is re-attached at a
subsequent port, unless the probe extensions are designed to be
locked into a mechanically fixed rotational position (e.g., through
use of interlocking grooves), which can be reproduced from port to
port as specified in section 8.3.5.2.
18.2 Annex B - Angle Measurement Protocol for Protractor Wheel
and Pointer Device. The following procedure shall be used when a
protractor wheel and pointer assembly, such as the one described in
section 6.2.2 and illustrated in Figure 2F-7 is used to measure the
yaw angle of flow. With each move to a new traverse point, unlock,
re-align, and re-lock the probe, angle-pointer collar, and
protractor wheel to each other. At each such move, particular
attention is required to ensure that the scribe line on the angle
pointer collar is either aligned with the reference scribe line on
the main probe sheath or is at the rotational offset position
established under section 8.3.1. The procedure consists of the
following steps:
18.2.1 Affix a protractor wheel to the entry port for the test
probe in the stack or duct.
18.2.2 Orient the protractor wheel so that the 0° mark
corresponds to the longitudinal axis of the stack or duct. For
stacks, vertical ducts, or ports on the side of horizontal ducts,
use a digital inclinometer meeting the specifications in section
6.2.1 to locate the 0° orientation. For ports on the top or bottom
of horizontal ducts, identify the longitudinal axis at each test
port and permanently mark the duct to indicate the 0° orientation.
Once the protractor wheel is properly aligned, lock it into
position on the test port.
18.2.3 Move the pointer assembly along the probe sheath to the
position needed to take measurements at the first traverse point.
Align the scribe line on the pointer collar with the reference
scribe line or at the rotational offset position established under
section 8.3.1. Maintaining this rotational alignment, lock the
pointer device onto the probe sheath. Insert the probe into the
entry port to the depth needed to take measurements at the first
traverse point.
18.2.4 Perform the yaw angle determination as specified in
sections 8.9.3 and 8.9.4 and record the angle as shown by the
pointer on the protractor wheel. Then, take velocity pressure and
temperature measurements in accordance with the procedure in
section 8.9.5. Perform the alignment check described in section
8.9.6.
18.2.5 After taking velocity pressure measurements at that
traverse point, unlock the probe from the collar and slide the
probe through the collar to the depth needed to reach the next
traverse point.
18.2.6 Align the scribe line on the pointer collar with the
reference scribe line on the main probe or at the rotational offset
position established under section 8.3.1. Lock the collar onto the
probe.
18.2.7 Repeat the steps in sections 18.2.4 through 18.2.6 at the
remaining traverse points accessed from the current stack or duct
entry port.
18.2.8 After completing the measurement at the last traverse
point accessed from a port, verify that the orientation of the
protractor wheel on the test port has not changed over the course
of the traverse at that port. For stacks, vertical ducts, or ports
on the side of horizontal ducts, use a digital inclinometer meeting
the specifications in section 6.2.1 to check the rotational
position of the 0° mark on the protractor wheel. For ports on the
top or bottom of horizontal ducts, observe the alignment of the
angle wheel 0° mark relative to the permanent 0° mark on the duct
at that test port. If these observed comparisons exceed ±2° of 0°,
all angle and pressure measurements taken at that port since the
protractor wheel was last locked into position on the port shall be
repeated.
18.2.9 Move to the next stack or duct entry port and repeat the
steps in sections 18.2.1 through 18.2.8.
18.3 Annex C - Guideline for Reference Scribe Line Placement.
Use of the following guideline is recommended to satisfy the
requirements of section 10.4 of this method. The rotational
position of the reference scribe line should be either 90° or 180°
from the probe's impact pressure port.
18.4 Annex D - Determination of Reference Scribe Line Rotational
Offset. The following procedures are recommended for determining
the magnitude and sign of a probe's reference scribe line
rotational offset, RSLO. Separate procedures are provided for two
types of angle-measuring devices: digital inclinometers and
protractor wheel and pointer assemblies.
18.4.1 Perform the following procedures on the main probe with
all devices that will be attached to the main probe in the field
[such as thermocouples or resistance temperature detectors (RTDs)]
that may affect the flow around the probe head. Probe shaft
extensions that do not affect flow around the probe head need not
be attached during calibration.
18.4.2 The procedures below assume that the wind tunnel duct
used for probe calibration is horizontal and that the flow in the
calibration wind tunnel is axial as determined by the axial flow
verification check described in section 10.1.2. Angle-measuring
devices are assumed to display angles in alternating 0° to 90° and
90° to 0° intervals. If angle-measuring devices with other readout
conventions are used or if other calibration wind tunnel duct
configurations are used, make the appropriate calculational
corrections.
18.4.2.1 Position the angle-measuring device in accordance with
one of the following procedures.
18.4.2.1.1 If using a digital inclinometer, affix the calibrated
digital inclinometer to the probe. If the digital inclinometer can
be independently adjusted after being locked into position on the
probe sheath (e.g., by means of a set screw), the independent
adjustment must be set so that the device performs exactly like a
device without the capability for independent adjustment. That is,
when aligned on the probe the device must give the same readings as
a device that does not have the capability of being independently
adjusted. Either align it directly on the reference scribe line or
on a mark aligned with the scribe line determined according to the
procedures in section 18.1.1.1. Maintaining this rotational
alignment, lock the digital inclinometer onto the probe sheath.
18.4.2.1.2 If using a protractor wheel and pointer device,
orient the protractor wheel on the test port so that the 0° mark is
aligned with the longitudinal axis of the wind tunnel duct.
Maintaining this alignment, lock the wheel into place on the wind
tunnel test port. Align the scribe line on the pointer collar with
the reference scribe line or with a mark aligned with the reference
scribe line, as determined under section 18.1.1.1. Maintaining this
rotational alignment, lock the pointer device onto the probe
sheath.
18.4.2.2 Zero the pressure-measuring device used for yaw
nulling.
18.4.2.3 Insert the probe assembly into the wind tunnel through
the entry port, positioning the probe's impact port at the
calibration location. Check the responsiveness of the
pressure-measuring device to probe rotation, taking corrective
action if the response is unacceptable.
18.4.2.4 Ensure that the probe is in a horizontal position using
a carpenter's level.
18.4.2.5 Rotate the probe either clockwise or counterclockwise
until a yaw null (P2 = P3) is obtained.
18.4.2.6 Read and record the value of θnull, the angle indicated
by the angle-measuring device at the yaw-null position. Record the
angle reading on a form similar to Table 2F-6. Do not associate an
algebraic sign with this reading.
18.4.2.7 Determine the magnitude and algebraic sign of the
reference scribe line rotational offset, RSLO. The magnitude of
RSLO will be equal to either θnull or (90°−θnull), depending on the
angle-measuring device used. (See Table 2F-7 for a summary.) The
algebraic sign of RSLO will either be positive, if the rotational
position of the reference scribe line is clockwise, or negative, if
counterclockwise with respect to the probe's yaw-null position.
Figure 2F-13 illustrates how the magnitude and sign of RSLO are
determined.
18.4.2.8 Perform the steps in sections 18.4.2.3 through 18.4.2.7
twice at each of the two calibration velocities selected for the
probe under section 10.6. Record the values of RSLO in a form
similar to Table 2F-6.
18.4.2.9 The average of all RSLO values is the reference scribe
line rotational offset for the probe.
[36 FR 24877, Dec.
23, 1971] Editorial Note:For Federal Register citations affecting
appendix A-1 to part 60, see the List of CFR sections Affected,
which appears in the Finding Aids section of the printed volume and
at www.govinfo.gov. Editorial Note:At 79 FR 11257, Feb. 27,
2014, Figure 1-2 was added to part 60, appendix A-1, method 1,
section 17. However, this amendment could not be performed because
Figure 1-2 already existed.
Appendix A-2 to Part 60 - Test Methods 2G through 3C
40:9.0.1.1.1.0.1.1.2 : Appendix A
Appendix A-2 to Part 60 - Test Methods 2G through 3C Method 2G -
Determination of Stack Gas Velocity and Volumetric Flow Rate With
Two-Dimensional Probes Method 2H - Determination of Stack Gas
Velocity Taking Into Account Velocity Decay Near the Stack Wall
Method 3 - Gas analysis for the determination of dry molecular
weight Method 3A - Determination of Oxygen and Carbon Dioxide
Concentrations in Emissions From Stationary Sources (Instrumental
Analyzer Procedure) Method 3B - Gas analysis for the determination
of emission rate correction factor or excess air Method 3C -
Determination of carbon dioxide, methane, nitrogen, and oxygen from
stationary sources
The test methods in this appendix are referred to in § 60.8
(Performance Tests) and § 60.11 (Compliance With Standards and
Maintenance Requirements) of 40 CFR part 60, subpart A (General
Provisions). Specific uses of these test methods are described in
the standards of performance contained in the subparts, beginning
with Subpart D.
Within each standard of performance, a section title “Test
Methods and Procedures” is provided to: (1) Identify the test
methods to be used as reference methods to the facility subject to
the respective standard and (2) identify any special instructions
or conditions to be followed when applying a method to the
respective facility. Such instructions (for example, establish
sampling rates, volumes, or temperatures) are to be used either in
addition to, or as a substitute for procedures in a test method.
Similarly, for sources subject to emission monitoring requirements,
specific instructions pertaining to any use of a test method as a
reference method are provided in the subpart or in Appendix B.
Inclusion of methods in this appendix is not intended as an
endorsement or denial of their applicability to sources that are
not subject to standards of performance. The methods are
potentially applicable to other sources; however, applicability
should be confirmed by careful and appropriate evaluation of the
conditions prevalent at such sources.
The approach followed in the formulation of the test methods
involves specifications for equipment, procedures, and performance.
In concept, a performance specification approach would be
preferable in all methods because this allows the greatest
flexibility to the user. In practice, however, this approach is
impractical in most cases because performance specifications cannot
be established. Most of the methods described herein, therefore,
involve specific equipment specifications and procedures, and only
a few methods in this appendix rely on performance criteria.
Minor changes in the test methods should not necessarily affect
the validity of the results and it is recognized that alternative
and equivalent methods exist. section 60.8 provides authority for
the Administrator to specify or approve (1) equivalent methods, (2)
alternative methods, and (3) minor changes in the methodology of
the test methods. It should be clearly understood that unless
otherwise identified all such methods and changes must have prior
approval of the Administrator. An owner employing such methods or
deviations from the test methods without obtaining prior approval
does so at the risk of subsequent disapproval and retesting with
approved methods.
Within the test methods, certain specific equipment or
procedures are recognized as being acceptable or potentially
acceptable and are specifically identified in the methods. The
items identified as acceptable options may be used without approval
but must be identified in the test report. The potentially
approvable options are cited as “subject to the approval of the
Administrator” or as “or equivalent.” Such potentially approvable
techniques or alternatives may be used at the discretion of the
owner without prior approval. However, detailed descriptions for
applying these potentially approvable techniques or alternatives
are not provided in the test methods. Also, the potentially
approvable options are not necessarily acceptable in all
applications. Therefore, an owner electing to use such potentially
approvable techniques or alternatives is responsible for: (1)
assuring that the techniques or alternatives are in fact applicable
and are properly executed; (2) including a written description of
the alternative method in the test report (the written method must
be clear and must be capable of being performed without additional
instruction, and the degree of detail should be similar to the
detail contained in the test methods); and (3) providing any
rationale or supporting data necessary to show the validity of the
alternative in the particular application. Failure to meet these
requirements can result in the Administrator's disapproval of the
alternative.
Method 2G - Determination of Stack Gas Velocity and Volumetric Flow
Rate With Two-Dimensional Probes Note:
This method does not include all of the specifications (e.g.,
equipment and supplies) and procedures (e.g., sampling) essential
to its performance. Some material has been incorporated from other
methods in this part. Therefore, to obtain reliable results, those
using this method should have a thorough knowledge of at least the
following additional test methods: Methods 1, 2, 3 or 3A, and
4.
1.0 Scope and Application
1.1 This method is applicable for the determination of yaw
angle, near-axial velocity, and the volumetric flow rate of a gas
stream in a stack or duct using a two-dimensional (2-D) probe.
2.0 Summary of Method 2.1 A 2-D probe is used to measure the
velocity pressure and the yaw angle of the flow velocity vector in
a stack or duct. Alternatively, these measurements may be made by
operating one of the three-dimensional (3-D) probes described in
Method 2F, in yaw determination mode only. From these measurements
and a determination of the stack gas density, the average
near-axial velocity of the stack gas is calculated. The near-axial
velocity accounts for the yaw, but not the pitch, component of
flow. The average gas volumetric flow rate in the stack or duct is
then determined from the average near-axial velocity. 3.0
Definitions
3.1. Angle-measuring Device Rotational Offset
(RADO). The rotational position of an angle-measuring
device relative to the reference scribe line, as determined during
the pre-test rotational position check described in section
8.3.
3.2 Calibration Pitot Tube. The standard (Prandtl type)
pitot tube used as a reference when calibrating a probe under this
method.
3.3 Field Test. A set of measurements conducted at a
specific unit or exhaust stack/duct to satisfy the applicable
regulation (e.g., a three-run boiler performance test, a single-or
multiple-load nine-run relative accuracy test).
3.4 Full Scale of Pressure-measuring Device. Full scale
refers to the upper limit of the measurement range displayed by the
device. For bi-directional pressure gauges, full scale includes the
entire pressure range from the lowest negative value to the highest
positive value on the pressure scale.
3.5 Main probe. Refers to the probe head and that section
of probe sheath directly attached to the probe head. The main probe
sheath is distinguished from probe extensions, which are sections
of sheath added onto the main probe to extend its reach.
3.6 “May,” “Must,” “Shall,” “Should,” and the imperative
form of verbs.
3.6.1 “May” is used to indicate that a provision of this
method is optional.
3.6.2 “Must,” “Shall,” and the imperative form of verbs
(such as “record” or “enter”) are used to indicate that a provision
of this method is mandatory.
3.6.3 “Should” is used to indicate that a provision of
this method is not mandatory, but is highly recommended as good
practice.
3.7 Method 1. Refers to 40 CFR part 60, appendix A,
“Method 1 - Sample and velocity traverses for stationary
sources.”
3.8 Method 2. Refers to 40 CFR part 60, appendix A,
“Method 2 - Determination of stack gas velocity and volumetric flow
rate (Type S pitot tube).”
3.9 Method 2F. Refers to 40 CFR part 60, appendix A,
“Method 2F - Determination of stack gas velocity and volumetric
flow rate with three-dimensional probes.”
3.10 Near-axial Velocity. The velocity vector parallel to
the axis of the stack or duct that accounts for the yaw angle
component of gas flow. The term “near-axial” is used herein to
indicate that the velocity and volumetric flow rate results account
for the measured yaw angle component of flow at each measurement
point.
3.11 Nominal Velocity. Refers to a wind tunnel velocity
setting that approximates the actual wind tunnel velocity to within
±1.5 m/sec (±5 ft/sec).
3.12 Pitch Angle. The angle between the axis of the stack
or duct and the pitch component of flow, i.e., the component of the
total velocity vector in a plane defined by the traverse line and
the axis of the stack or duct. (Figure 2G-1 illustrates the “pitch
plane.”) From the standpoint of a tester facing a test port in a
vertical stack, the pitch component of flow is the vector of flow
moving from the center of the stack toward or away from that test
port. The pitch angle is the angle described by this pitch
component of flow and the vertical axis of the stack.
3.13 Readability. For the purposes of this method,
readability for an analog measurement device is one half of the
smallest scale division. For a digital measurement device, it is
the number of decimals displayed by the device.
3.14 Reference Scribe Line. A line permanently inscribed
on the main probe sheath (in accordance with section 6.1.5.1) to
serve as a reference mark for determining yaw angles.
3.15 Reference Scribe Line Rotational Offset
(RSLO). The rotational position of a probe's reference
scribe line relative to the probe's yaw-null position, as
determined during the yaw angle calibration described in section
10.5.
3.16 Response Time. The time required for the measurement
system to fully respond to a change from zero differential pressure
and ambient temperature to the stable stack or duct pressure and
temperature readings at a traverse point.
3.17 Tested Probe. A probe that is being calibrated.
3.18 Three-dimensional (3-D) Probe. A directional probe
used to determine the velocity pressure and the yaw and pitch
angles in a flowing gas stream.
3.19 Two-dimensional (2-D) Probe. A directional probe
used to measure velocity pressure and yaw angle in a flowing gas
stream.
3.20 Traverse Line. A diameter or axis extending across a
stack or duct on which measurements of velocity pressure and flow
angles are made.
3.21 Wind Tunnel Calibration Location. A point, line,
area, or volume within the wind tunnel test section at, along, or
within which probes are calibrated. At a particular wind tunnel
velocity setting, the average velocity pressures at specified
points at, along, or within the calibration location shall vary by
no more than 2 percent or 0.3 mm H20 (0.01 in. H2O), whichever is
less restrictive, from the average velocity pressure at the
calibration pitot tube location. Air flow at this location shall be
axial, i.e., yaw and pitch angles within ±3° of 0°. Compliance with
these flow criteria shall be demonstrated by performing the
procedures prescribed in sections 10.1.1 and 10.1.2. For circular
tunnels, no part of the calibration location may be closer to the
tunnel wall than 10.2 cm (4 in.) or 25 percent of the tunnel
diameter, whichever is farther from the wall. For elliptical or
rectangular tunnels, no part of the calibration location may be
closer to the tunnel wall than 10.2 cm (4 in.) or 25 percent of the
applicable cross-sectional axis, whichever is farther from the
wall.
3.22 Wind Tunnel with Documented Axial Flow. A wind
tunnel facility documented as meeting the provisions of sections
10.1.1 (velocity pressure cross-check) and 10.1.2 (axial flow
verification) using the procedures described in these sections or
alternative procedures determined to be technically equivalent.
3.23 Yaw Angle. The angle between the axis of the stack
or duct and the yaw component of flow, i.e., the component of the
total velocity vector in a plane perpendicular to the traverse line
at a particular traverse point. (Figure 2G-1 illustrates the “yaw
plane.”) From the standpoint of a tester facing a test port in a
vertical stack, the yaw component of flow is the vector of flow
moving to the left or right from the center of the stack as viewed
by the tester. (This is sometimes referred to as “vortex flow,”
i.e., flow around the centerline of a stack or duct.) The yaw angle
is the angle described by this yaw component of flow and the
vertical axis of the stack. The algebraic sign convention is
illustrated in Figure 2G-2.
3.24 Yaw Nulling. A procedure in which a Type-S pitot
tube or a 3-D probe is rotated about its axis in a stack or duct
until a zero differential pressure reading (“yaw null”) is
obtained. When a Type S probe is yaw-nulled, the rotational
position of its impact port is 90° from the direction of flow in
the stack or duct and the ΔP reading is zero. When a 3-D probe is
yaw-nulled, its impact pressure port (P1) faces directly into the
direction of flow in the stack or duct and the differential
pressure between pressure ports P2 and P3 is zero.
4.0 Interferences [Reserved] 5.0 Safety
5.1 This test method may involve hazardous operations and the
use of hazardous materials or equipment. This method does not
purport to address all of the safety problems associated with its
use. It is the responsibility of the user to establish and
implement appropriate safety and health practices and to determine
the applicability of regulatory limitations before using this test
method.
6.0 Equipment and Supplies
6.1 Two-dimensional Probes. Probes that provide both the
velocity pressure and the yaw angle of the flow vector in a stack
or duct, as listed in sections 6.1.1 and 6.1.2, qualify for use
based on comprehensive wind tunnel and field studies involving both
inter-and intra-probe comparisons by multiple test teams. Each 2-D
probe shall have a unique identification number or code permanently
marked on the main probe sheath. Each probe shall be calibrated
prior to use according to the procedures in section 10.
Manufacturer-supplied calibration data shall be used as example
information only, except when the manufacturer calibrates the probe
as specified in section 10 and provides complete documentation.
6.1.1 Type S (Stausscheibe or reverse type) pitot tube. This is
the same as specified in Method 2, section 2.1, except for the
following additional specifications that enable the pitot tube to
accurately determine the yaw component of flow. For the purposes of
this method, the external diameter of the tubing used to construct
the Type S pitot tube (dimension Dt in Figure 2-2 of Method 2)
shall be no less than 9.5 mm (3/8 in.). The pitot tube shall also
meet the following alignment specifications. The angles α1, α2, β1,
and β2, as shown in Method 2, Figure 2-3, shall not exceed ±2°. The
dimensions w and z, shown in Method 2, Figure 2-3
shall not exceed 0.5 mm (0.02 in.).
6.1.1.1 Manual Type S probe. This refers to a Type S probe that
is positioned at individual traverse points and yaw nulled manually
by an operator.
6.1.1.2 Automated Type S probe. This refers to a system that
uses a computer-controlled motorized mechanism to position the Type
S pitot head at individual traverse points and perform yaw angle
determinations.
6.1.2 Three-dimensional probes used in 2-D mode. A 3-D probe, as
specified in sections 6.1.1 through 6.1.3 of Method 2F, may, for
the purposes of this method, be used in a two-dimensional mode
(i.e., measuring yaw angle, but not pitch angle). When the 3-D
probe is used as a 2-D probe, only the velocity pressure and
yaw-null pressure are obtained using the pressure taps referred to
as P1, P2, and P3. The differential pressure P1-P2 is a function of
total velocity and corresponds to the ΔP obtained using the Type S
probe. The differential pressure P2-P3 is used to yaw null the
probe and determine the yaw angle. The differential pressure P4-P5,
which is a function of pitch angle, is not measured when the 3-D
probe is used in 2-D mode.
6.1.3 Other probes. [Reserved]
6.1.4 Probe sheath. The probe shaft shall include an outer
sheath to: (1) provide a surface for inscribing a permanent
reference scribe line, (2) accommodate attachment of an
angle-measuring device to the probe shaft, and (3) facilitate
precise rotational movement of the probe for determining yaw
angles. The sheath shall be rigidly attached to the probe assembly
and shall enclose all pressure lines from the probe head to the
farthest position away from the probe head where an angle-measuring
device may be attached during use in the field. The sheath of the
fully assembled probe shall be sufficiently rigid and straight at
all rotational positions such that, when one end of the probe shaft
is held in a horizontal position, the fully extended probe meets
the horizontal straightness specifications indicated in section 8.2
below.
6.1.5 Scribe lines.
6.1.5.1 Reference scribe line. A permanent line, no greater than
1.6 mm (1/16 in.) in width, shall be inscribed on each manual probe
that will be used to determine yaw angles of flow. This line shall
be placed on the main probe sheath in accordance with the
procedures described in section 10.4 and is used as a reference
position for installation of the yaw angle-measuring device on the
probe. At the discretion of the tester, the scribe line may be a
single line segment placed at a particular position on the probe
sheath (e.g., near the probe head), multiple line segments placed
at various locations along the length of the probe sheath (e.g., at
every position where a yaw angle-measuring device may be mounted),
or a single continuous line extending along the full length of the
probe sheath.
6.1.5.2 Scribe line on probe extensions. A permanent line may
also be inscribed on any probe extension that will be attached to
the main probe in performing field testing. This allows a yaw
angle-measuring device mounted on the extension to be readily
aligned with the reference scribe line on the main probe
sheath.
6.1.5.3 Alignment specifications. This specification shall be
met separately, using the procedures in section 10.4.1, on the main
probe and on each probe extension. The rotational position of the
scribe line or scribe line segments on the main probe or any probe
extension must not vary by more than 2°. That is, the difference
between the minimum and maximum of all of the rotational angles
that are measured along the full length of the main probe or the
probe extension must not exceed 2°.
6.1.6 Probe and system characteristics to ensure horizontal
stability.
6.1.6.1 For manual probes, it is recommended that the effective
length of the probe (coupled with a probe extension, if necessary)
be at least 0.9 m (3 ft.) longer than the farthest traverse point
mark on the probe shaft away from the probe head. The operator
should maintain the probe's horizontal stability when it is fully
inserted into the stack or duct. If a shorter probe is used, the
probe should be inserted through a bushing sleeve, similar to the
one shown in Figure 2G-3, that is installed on the test port; such
a bushing shall fit snugly around the probe and be secured to the
stack or duct entry port in such a manner as to maintain the
probe's horizontal stability when fully inserted into the stack or
duct.
6.1.6.2 An automated system that includes an external probe
casing with a transport system shall have a mechanism for
maintaining horizontal stability comparable to that obtained by
manual probes following the provisions of this method. The
automated probe assembly shall also be constructed to maintain the
alignment and position of the pressure ports during sampling at
each traverse point. The design of the probe casing and transport
system shall allow the probe to be removed from the stack or duct
and checked through direct physical measurement for angular
position and insertion depth.
6.1.7 The tubing that is used to connect the probe and the
pressure-measuring device should have an inside diameter of at
least 3.2 mm ( 1/8 in.), to reduce the time required for pressure
equilibration, and should be as short as practicable.
6.1.8 If a detachable probe head without a sheath [e.g., a pitot
tube, typically 15.2 to 30.5 cm (6 to 12 in.) in length] is coupled
with a probe sheath and calibrated in a wind tunnel in accordance
with the yaw angle calibration procedure in section 10.5, the probe
head shall remain attached to the probe sheath during field testing
in the same configuration and orientation as calibrated. Once the
detachable probe head is uncoupled or re-oriented, the yaw angle
calibration of the probe is no longer valid and must be repeated
before using the probe in subsequent field tests.
6.2 Yaw Angle-measuring Device. One of the following devices
shall be used for measurement of the yaw angle of flow.
6.2.1 Digital inclinometer. This refers to a digital device
capable of measuring and displaying the rotational position of the
probe to within ±1°. The device shall be able to be locked into
position on the probe sheath or probe extension, so that it
indicates the probe's rotational position throughout the test. A
rotational position collar block that can be attached to the probe
sheath (similar to the collar shown in Figure 2G-4) may be required
to lock the digital inclinometer into position on the probe
sheath.
6.2.2 Protractor wheel and pointer assembly. This apparatus,
similar to that shown in Figure 2G-5, consists of the following
components.
6.2.2.1 A protractor wheel that can be attached to a port
opening and set in a fixed rotational position to indicate the yaw
angle position of the probe's scribe line relative to the
longitudinal axis of the stack or duct. The protractor wheel must
have a measurement ring on its face that is no less than 17.8 cm (7
in.) in diameter, shall be able to be rotated to any angle and then
locked into position on the stack or duct test port, and shall
indicate angles to a resolution of 1°.
6.2.2.2 A pointer assembly that includes an indicator needle
mounted on a collar that can slide over the probe sheath and be
locked into a fixed rotational position on the probe sheath. The
pointer needle shall be of sufficient length, rigidity, and
sharpness to allow the tester to determine the probe's angular
position to within 1° from the markings on the protractor wheel.
Corresponding to the position of the pointer, the collar must have
a scribe line to be used in aligning the pointer with the scribe
line on the probe sheath.
6.2.3 Other yaw angle-measuring devices. Other angle-measuring
devices with a manufacturer's specified precision of 1° or better
may be used, if approved by the Administrator.
6.3 Probe Supports and Stabilization Devices. When probes are
used for determining flow angles, the probe head should be kept in
a stable horizontal position. For probes longer than 3.0 m (10
ft.), the section of the probe that extends outside the test port
shall be secured. Three alternative devices are suggested for
maintaining the horizontal position and stability of the probe
shaft during flow angle determinations and velocity pressure
measurements: (1) monorails installed above each port, (2) probe
stands on which the probe shaft may be rested, or (3) bushing
sleeves of sufficient length secured to the test ports to maintain
probes in a horizontal position. Comparable provisions shall be
made to ensure that automated systems maintain the horizontal
position of the probe in the stack or duct. The physical
characteristics of each test platform may dictate the most suitable
type of stabilization device. Thus, the choice of a specific
stabilization device is left to the judgement of the testers.
6.4 Differential Pressure Gauges. The velocity pressure (ΔP)
measuring devices used during wind tunnel calibrations and field
testing shall be either electronic manometers (e.g., pressure
transducers), fluid manometers, or mechanical pressure gauges
(e.g., MagnehelicΔ gauges). Use of electronic manometers is
recommended. Under low velocity conditions, use of electronic
manometers may be necessary to obtain acceptable measurements.
6.4.1 Differential pressure-measuring device. This refers to a
device capable of measuring pressure differentials and having a
readability of ±1 percent of full scale. The device shall be
capable of accurately measuring the maximum expected pressure
differential. Such devices are used to determine the following
pressure measurements: velocity pressure, static pressure, and
yaw-null pressure. For an inclined-vertical manometer, the
readability specification of ±1 percent shall be met separately
using the respective full-scale upper limits of the inclined
anvertical portions of the scales. To the extent practicable, the
device shall be selected such that most of the pressure readings
are between 10 and 90 percent of the device's full-scale
measurement range (as defined in section 3.4). In addition,
pressure-measuring devices should be selected such that the zero
does not drift by more than 5 percent of the average expected
pressure readings to be encountered during the field test. This is
particularly important under low pressure conditions.
6.4.2 Gauge used for yaw nulling. The differential
pressure-measuring device chosen for yaw nulling the probe during
the wind tunnel calibrations and field testing shall be
bi-directional, i.e., capable of reading both positive and negative
differential pressures. If a mechanical, bi-directional pressure
gauge is chosen, it shall have a full-scale range no greater than
2.6 cm (i.e., −1.3 to + 1.3 cm) [1 in. H2O (i.e., −0.5 in. to + 0.5
in.)].
6.4.3 Devices for calibrating differential pressure-measuring
devices. A precision manometer (e.g., a U-tube, inclined, or
inclined-vertical manometer, or micromanometer) or NIST (National
Institute of Standards and Technology) traceable pressure source
shall be used for calibrating differential pressure-measuring
devices. The device shall be maintained under laboratory conditions
or in a similar protected environment (e.g., a climate-controlled
trailer). It shall not be used in field tests. The precision
manometer shall have a scale gradation of 0.3 mm H2O (0.01 in.
H2O), or less, in the range of 0 to 5.1 cm H2O (0 to 2 in. H2O) and
2.5 mm H2O (0.1 in. H2O), or less, in the range of 5.1 to 25.4 cm
H2O (2 to 10 in. H2O). The manometer shall have manufacturer's
documentation that it meets an accuracy specification of at least
0.5 percent of full scale. The NIST-traceable pressure source shall
be recertified annually.
6.4.4 Devices used for post-test calibration check. A precision
manometer meeting the specifications in section 6.4.3, a
pressure-measuring device or pressure source with a documented
calibration traceable to NIST, or an equivalent device approved by
the Administrator shall be used for the post-test calibration
check. The pressure-measuring device shall have a readability
equivalent to or greater than the tested device. The pressure
source shall be capable of generating pressures between 50 and 90
percent of the range of the tested device and known to within ±1
percent of the full scale of the tested device. The pressure source
shall be recertified annually.
6.5 Data Display and Capture Devices. Electronic manometers (if
used) shall be coupled with a data display device (such as a
digital panel meter, personal computer display, or strip chart)
that allows the tester to observe and validate the pressure
measurements taken during testing. They shall also be connected to
a data recorder (such as a data logger or a personal computer with
data capture software) that has the ability to compute and retain
the appropriate average value at each traverse point, identified by
collection time and traverse point.
6.6 Temperature Gauges. For field tests, a thermocouple or
resistance temperature detector (RTD) capable of measuring
temperature to within ±3 °C (±5 °F) of the stack or duct
temperature shall be used. The thermocouple shall be attached to
the probe such that the sensor tip does not touch any metal. The
position of the thermocouple relative to the pressure port face
openings shall be in the same configuration as used for the probe
calibrations in the wind tunnel. Temperature gauges used for wind
tunnel calibrations shall be capable of measuring temperature to
within ±0.6 °C (±1 °F) of the temperature of the flowing gas stream
in the wind tunnel.
6.7 Stack or Duct Static Pressure Measurement. The
pressure-measuring device used with the probe shall be as specified
in section 6.4 of this method. The static tap of a standard
(Prandtl type) pitot tube or one leg of a Type S pitot tube with
the face opening planes positioned parallel to the gas flow may be
used for this measurement. Also acceptable is the pressure
differential reading of P1-Pbar from a five-hole prism-shaped 3-D
probe, as specified in section 6.1.1 of Method 2F (such as the Type
DA or DAT probe), with the P1 pressure port face opening positioned
parallel to the gas flow in the same manner as the Type S probe.
However, the 3-D spherical probe, as specified in section 6.1.2 of
Method 2F, is unable to provide this measurement and shall not be
used to take static pressure measurements. Static pressure
measurement is further described in section 8.11.
6.8 Barometer. Same as Method 2, section 2.5.
6.9 Gas Density Determination Equipment. Method 3 or 3A shall be
used to determine the dry molecular weight of the stack or duct
gas. Method 4 shall be used for moisture content determination and
computation of stack or duct gas wet molecular weight. Other
methods may be used, if approved by the Administrator.
6.10 Calibration Pitot Tube. Same as Method 2, section 2.7.
6.11 Wind Tunnel for Probe Calibration. Wind tunnels used to
calibrate velocity probes must meet the following design
specifications.
6.11.1 Test section cross-sectional area. The flowing gas stream
shall be confined within a circular, rectangular, or elliptical
duct. The cross-sectional area of the tunnel must be large enough
to ensure fully developed flow in the presence of both the
calibration pitot tube and the tested probe. The calibration site,
or “test section,” of the wind tunnel shall have a minimum diameter
of 30.5 cm (12 in.) for circular or elliptical duct cross-sections
or a minimum width of 30.5 cm (12 in.) on the shorter side for
rectangular cross-sections. Wind tunnels shall meet the probe
blockage provisions of this section and the qualification
requirements prescribed in section 10.1. The projected area of the
portion of the probe head, shaft, and attached devices inside the
wind tunnel during calibration shall represent no more than 2
percent of the cross-sectional area of the tunnel. If the pitot
and/or probe assembly blocks more than 2 percent of the
cross-sectional area at an insertion point only 4 inches inside the
wind tunnel, the diameter of the wind tunnel must be increased.
6.11.2 Velocity range and stability. The wind tunnel should be
capable of achieving and maintaining a constant and steady velocity
between 6.1 m/sec and 30.5 m/sec (20 ft/sec and 100 ft/sec) for the
entire calibration period for each selected calibration velocity.
The wind tunnel shall produce fully developed flow patterns that
are stable and parallel to the axis of the duct in the test
section.
6.11.3 Flow profile at the calibration location. The wind tunnel
shall provide axial flow within the test section calibration
location (as defined in section 3.21). Yaw and pitch angles in the
calibration location shall be within ±3° of 0°. The procedure for
determining that this requirement has been met is described in
section 10.1.2.
6.11.4 Entry ports in the wind tunnel test section.
6.11.4.1 Port for tested probe. A port shall be constructed for
the tested probe. This port shall be located to allow the head of
the tested probe to be positioned within the wind tunnel
calibration location (as defined in section 3.21). The tested probe
shall be able to be locked into the 0° pitch angle position. To
facilitate alignment of the probe during calibration, the test
section should include a window constructed of a transparent
material to allow the tested probe to be viewed.
6.11.4.2 Port for verification of axial flow. Depending on the
equipment selected to conduct the axial flow verification
prescribed in section 10.1.2, a second port, located 90° from the
entry port for the tested probe, may be needed to allow
verification that the gas flow is parallel to the central axis of
the test section. This port should be located and constructed so as
to allow one of the probes described in section 10.1.2.2 to access
the same test point(s) that are accessible from the port described
in section 6.11.4.1.
6.11.4.3 Port for calibration pitot tube. The calibration pitot
tube shall be used in the port for the tested probe or in a
separate entry port. In either case, all measurements with the
calibration pitot tube shall be made at the same point within the
wind tunnel over the course of a probe calibration. The measurement
point for the calibration pitot tube shall meet the same
specifications for distance from the wall and for axial flow as
described in section 3.21 for the wind tunnel calibration
location.
7.0 Reagents and Standards [Reserved] 8.0 Sample Collection and
Analysis
8.1 Equipment Inspection and Set Up
8.1.1 All 2-D and 3-D probes, differential pressure-measuring
devices, yaw angle-measuring devices, thermocouples, and barometers
shall have a current, valid calibration before being used in a
field test. (See sections 10.3.3, 10.3.4, and 10.5 through 10.10
for the applicable calibration requirements.)
8.1.2 Before each field use of a Type S probe, perform a visual
inspection to verify the physical condition of the pitot tube.
Record the results of the inspection. If the face openings are
noticeably misaligned or there is visible damage to the face
openings, the probe shall not be used until repaired, the
dimensional specifications verified (according to the procedures in
section 10.2.1), and the probe recalibrated.
8.1.3 Before each field use of a 3-D probe, perform a visual
inspection to verify the physical condition of the probe head
according to the procedures in section 10.2 of Method 2F. Record
the inspection results on a form similar to Table 2F-1 presented in
Method 2F. If there is visible damage to the 3-D probe, the probe
shall not be used until it is recalibrated.
8.1.4 After verifying that the physical condition of the probe
head is acceptable, set up the apparatus using lengths of flexible
tubing that are as short as practicable. Surge tanks installed
between the probe and pressure-measuring device may be used to
dampen pressure fluctuations provided that an adequate measurement
system response time (see section 8.8) is maintained.
8.2 Horizontal Straightness Check. A horizontal straightness
check shall be performed before the start of each field test,
except as otherwise specified in this section. Secure the fully
assembled probe (including the probe head and all probe shaft
extensions) in a horizontal position using a stationary support at
a point along the probe shaft approximating the location of the
stack or duct entry port when the probe is sampling at the farthest
traverse point from the stack or duct wall. The probe shall be
rotated to detect bends. Use an angle-measuring device or
trigonometry to determine the bend or sag between the probe head
and the secured end. (See Figure 2G-6.) Probes that are bent or sag
by more than 5° shall not be used. Although this check does not
apply when the probe is used for a vertical traverse, care should
be taken to avoid the use of bent probes when conducting vertical
traverses. If the probe is constructed of a rigid steel material
and consists of a main probe without probe extensions, this check
need only be performed before the initial field use of the probe,
when the probe is recalibrated, when a change is made to the design
or material of the probe assembly, and when the probe becomes bent.
With such probes, a visual inspection shall be made of the fully
assembled probe before each field test to determine if a bend is
visible. The probe shall be rotated to detect bends. The inspection
results shall be documented in the field test report. If a bend in
the probe is visible, the horizontal straightness check shall be
performed before the probe is used.
8.3 Rotational Position Check. Before each field test, and each
time an extension is added to the probe during a field test, a
rotational position check shall be performed on all manually
operated probes (except as noted in section 8.3.5 below) to ensure
that, throughout testing, the angle-measuring device is either:
aligned to within ±1° of the rotational position of the reference
scribe line; or is affixed to the probe such that the rotational
offset of the device from the reference scribe line is known to
within ±1°. This check shall consist of direct measurements of the
rotational positions of the reference scribe line and
angle-measuring device sufficient to verify that these
specifications are met. Annex A in section 18 of this method gives
recommended procedures for performing the rotational position
check, and Table 2G-2 gives an example data form. Procedures other
than those recommended in Annex A in section 18 may be used,
provided they demonstrate whether the alignment specification is
met and are explained in detail in the field test report.
8.3.1 Angle-measuring device rotational offset. The tester shall
maintain a record of the angle-measuring device rotational offset,
RADO, as defined in section 3.1. Note that RADO is assigned a value
of 0° when the angle-measuring device is aligned to within ±1° of
the rotational position of the reference scribe line. The RADO
shall be used to determine the yaw angle of flow in accordance with
section 8.9.4.
8.3.2 Sign of angle-measuring device rotational offset. The sign
of RADO is positive when the angle-measuring device (as viewed from
the “tail” end of the probe) is positioned in a clockwise direction
from the reference scribe line and negative when the device is
positioned in a counterclockwise direction from the reference
scribe line.
8.3.3 Angle-measuring devices that can be independently adjusted
(e.g., by means of a set screw), after being locked into position
on the probe sheath, may be used. However, the RADO must also take
into account this adjustment.
8.3.4 Post-test check. If probe extensions remain attached to
the main probe throughout the field test, the rotational position
check shall be repeated, at a minimum, at the completion of the
field test to ensure that the angle-measuring device has remained
within ±2° of its rotational position established prior to testing.
At the discretion of the tester, additional checks may be conducted
after completion of testing at any sample port or after any test
run. If the ±2° specification is not met, all measurements made
since the last successful rotational position check must be
repeated. section 18.1.1.3 of Annex A provides an example procedure
for performing the post-test check.
8.3.5 Exceptions.
8.3.5.1 A rotational position check need not be performed if,
for measurements taken at all velocity traverse points, the yaw
angle-measuring device is mounted and aligned directly on the
reference scribe line specified in sections 6.1.5.1 and 6.1.5.3 and
no independent adjustments, as described in section 8.3.3, are made
to device's rotational position.
8.3.5.2 If extensions are detached and re-attached to the probe
during a field test, a rotational position check need only be
performed the first time an extension is added to the probe, rather
than each time the extension is re-attached, if the probe extension
is designed to be locked into a mechanically fixed rotational
position (e.g., through the use of interlocking grooves), that can
re-establish the initial rotational position to within ±1°.
8.4 Leak Checks. A pre-test leak check shall be conducted before
each field test. A post-test check shall be performed at the end of
the field test, but additional leak checks may be conducted after
any test run or group of test runs. The post-test check may also
serve as the pre-test check for the next group of test runs. If any
leak check is failed, all runs since the last passed leak check are
invalid. While performing the leak check procedures, also check
each pressure device's responsiveness to changes in pressure.
8.4.1 To perform the leak check on a Type S pitot tube,
pressurize the pitot impact opening until at least 7.6 cm H2O (3
in. H2O) velocity pressure, or a pressure corresponding to
approximately 75 percent of the pressure device's measurement
scale, whichever is less, registers on the pressure device; then,
close off the impact opening. The pressure shall remain stable
(±2.5 mm H2O, ±0.10 in. H2O) for at least 15 seconds. Repeat this
procedure for the static pressure side, except use suction to
obtain the required pressure. Other leak-check procedures may be
used, if approved by the Administrator.
8.4.2 To perform the leak check on a 3-D probe, pressurize the
probe's impact (P1) opening until at least 7.6 cm H2O (3 in. H2O)
velocity pressure, or a pressure corresponding to approximately 75
percent of the pressure device's measurement scale, whichever is
less, registers on the pressure device; then, close off the impact
opening. The pressure shall remain stable (±2.5 mm H2O, ±0.10 in.
H2O) for at least 15 seconds. Check the P2 and P3 pressure ports in
the same fashion. Other leak-check procedures may be used, if
approved by the Administrator.
8.5 Zeroing the Differential Pressure-measuring Device. Zero
each differential pressure-measuring device, including the device
used for yaw nulling, before each field test. At a minimum, check
the zero after each field test. A zero check may also be performed
after any test run or group of test runs. For fluid manometers and
mechanical pressure gauges (e.g., MagnehelicΔ gauges), the zero
reading shall not deviate from zero by more than ±0.8 mm H2O (±0.03
in. H2O) or one minor scale division, whichever is greater, between
checks. For electronic manometers, the zero reading shall not
deviate from zero between checks by more than: ±0.3 mm H2O (±0.01
in. H2O), for full scales less than or equal to 5.1 cm H2O (2.0 in.
H2O); or ±0.8 mm H2O (±0.03 in. H2O), for full scales greater than
5.1 cm H2O (2.0 in. H2O). (Note: If negative zero drift is not
directly readable, estimate the reading based on the position of
the gauge oil in the manometer or of the needle on the pressure
gauge.) In addition, for all pressure-measuring devices except
those used exclusively for yaw nulling, the zero reading shall not
deviate from zero by more than 5 percent of the average measured
differential pressure at any distinct process condition or load
level. If any zero check is failed at a specific process condition
or load level, all runs conducted at that process condition or load
level since the last passed zero check are invalid.
8.6 Traverse Point Verification. The number and location of the
traverse points shall be selected based on Method 1 guidelines. The
stack or duct diameter and port nipple lengths, including any
extension of the port nipples into the stack or duct, shall be
verified the first time the test is performed; retain and use this
information for subsequent field tests, updating it as required.
Physically measure the stack or duct dimensions or use a calibrated
laser device; do not use engineering drawings of the stack or duct.
The probe length necessary to reach each traverse point shall be
recorded to within ±6.4 mm (± 1/4 in.) and, for manual probes,
marked on the probe sheath. In determining these lengths, the
tester shall take into account both the distance that the port
flange projects outside of the stack and the depth that any port
nipple extends into the gas stream. The resulting point positions
shall reflect the true distances from the inside wall of the stack
or duct, so that when the tester aligns any of the markings with
the outside face of the stack port, the probe's impact port shall
be located at the appropriate distance from the inside wall for the
respective Method 1 traverse point. Before beginning testing at a
particular location, an out-of-stack or duct verification shall be
performed on each probe that will be used to ensure that these
position markings are correct. The distances measured during the
verification must agree with the previously calculated distances to
within ± 1/4 in. For manual probes, the traverse point positions
shall be verified by measuring the distance of each mark from the
probe's impact pressure port (the P1 port for a 3-D probe). A
comparable out-of-stack test shall be performed on automated probe
systems. The probe shall be extended to each of the prescribed
traverse point positions. Then, the accuracy of the positioning for
each traverse point shall be verified by measuring the distance
between the port flange and the probe's impact pressure port.
8.7 Probe Installation. Insert the probe into the test port. A
solid material shall be used to seal the port.
8.8 System Response Time. Determine the response time of the
probe measurement system. Insert and position the “cold” probe (at
ambient temperature and pressure) at any Method 1 traverse point.
Read and record the probe differential pressure, temperature, and
elapsed time at 15-second intervals until stable readings for both
pressure and temperature are achieved. The response time is the
longer of these two elapsed times. Record the response time.
8.9 Sampling.
8.9.1 Yaw angle measurement protocol. With manual probes, yaw
angle measurements may be obtained in two alternative ways during
the field test, either by using a yaw angle-measuring device (e.g.,
digital inclinometer) affixed to the probe, or using a protractor
wheel and pointer assembly. For horizontal traversing, either
approach may be used. For vertical traversing, i.e., when measuring
from on top or into the bottom of a horizontal duct, only the
protractor wheel and pointer assembly may be used. With automated
probes, curve-fitting protocols may be used to obtain yaw-angle
measurements.
8.9.1.1 If a yaw angle-measuring device affixed to the probe is
to be used, lock the device on the probe sheath, aligning it either
on the reference scribe line or in the rotational offset position
established under section 8.3.1.
8.9.1.2 If a protractor wheel and pointer assembly is to be
used, follow the procedures in Annex B of this method.
8.9.1.3 Curve-fitting procedures. Curve-fitting routines sweep
through a range of yaw angles to create curves correlating pressure
to yaw position. To find the zero yaw position and the yaw angle of
flow, the curve found in the stack is computationally compared to a
similar curve that was previously generated under controlled
conditions in a wind tunnel. A probe system that uses a
curve-fitting routine for determining the yaw-null position of the
probe head may be used, provided that it is verified in a wind
tunnel to be able to determine the yaw angle of flow to within
±1°.
8.9.1.4 Other yaw angle determination procedures. If approved by
the Administrator, other procedures for determining yaw angle may
be used, provided that they are verified in a wind tunnel to be
able to perform the yaw angle calibration procedure as described in
section 10.5.
8.9.2 Sampling strategy. At each traverse point, first yaw-null
the probe, as described in section 8.9.3, below. Then, with the
probe oriented into the direction of flow, measure and record the
yaw angle, the differential pressure and the temperature at the
traverse point, after stable readings are achieved, in accordance
with sections 8.9.4 and 8.9.5. At the start of testing in each port
(i.e., after a probe has been inserted into the flue gas stream),
allow at least the response time to elapse before beginning to take
measurements at the first traverse point accessed from that port.
Provided that the probe is not removed from the flue gas stream,
measurements may be taken at subsequent traverse points accessed
from the same test port without waiting again for the response time
to elapse.
8.9.3 Yaw-nulling procedure. In preparation for yaw angle
determination, the probe must first be yaw nulled. After
positioning the probe at the appropriate traverse point, perform
the following procedures.
8.9.3.1 For Type S probes, rotate the probe until a null
differential pressure reading is obtained. The direction of the
probe rotation shall be such that the thermocouple is located
downstream of the probe pressure ports at the yaw-null position.
Rotate the probe 90° back from the yaw-null position to orient the
impact pressure port into the direction of flow. Read and record
the angle displayed by the angle-measuring device.
8.9.3.2 For 3-D probes, rotate the probe until a null
differential pressure reading (the difference in pressures across
the P2 and P3 pressure ports is zero, i.e., P2 = P3) is indicated
by the yaw angle pressure gauge. Read and record the angle
displayed by the angle-measuring device.
8.9.3.3 Sign of the measured angle. The angle displayed on the
angle-measuring device is considered positive when the probe's
impact pressure port (as viewed from the “tail” end of the probe)
is oriented in a clockwise rotational position relative to the
stack or duct axis and is considered negative when the probe's
impact pressure port is oriented in a counterclockwise rotational
position (see Figure 2G-7).
8.9.4 Yaw angle determination. After performing the applicable
yaw-nulling procedure in section 8.9.3, determine the yaw angle of
flow according to one of the following procedures. Special care
must be observed to take into account the signs of the recorded
angle reading and all offsets.
8.9.4.1 Direct-reading. If all rotational offsets are zero or if
the angle-measuring device rotational offset (RADO) determined in
section 8.3 exactly compensates for the scribe line rotational
offset (RSLO) determined in section 10.5, then the magnitude of the
yaw angle is equal to the displayed angle-measuring device reading
from section 8.9.3.1 or 8.9.3.2. The algebraic sign of the yaw
angle is determined in accordance with section 8.9.3.3. [Note:
Under certain circumstances (e.g., testing of horizontal ducts) a
90° adjustment to the angle-measuring device readings may be
necessary to obtain the correct yaw angles.]
8.9.4.2 Compensation for rotational offsets during data
reduction. When the angle-measuring device rotational offset does
not compensate for reference scribe line rotational offset, the
following procedure shall be used to determine the yaw angle:
(a) Enter the reading indicated by the angle-measuring device
from section 8.9.3.1 or 8.9.3.2.
(b) Associate the proper algebraic sign from section 8.9.3.3
with the reading in step (a).
(c) Subtract the reference scribe line rotational offset, RSLO,
from the reading in step (b).
(d) Subtract the angle-measuring device rotational offset, RADO,
if any, from the result obtained in step (c).
(e) The final result obtained in step (d) is the yaw angle of
flow.
Note:
It may be necessary to first apply a 90° adjustment to the
reading in step (a), in order to obtain the correct yaw angle.
8.9.4.3 Record the yaw angle measurements on a form similar to
Table 2G-3.
8.9.5 Impact velocity determination. Maintain the probe
rotational position established during the yaw angle determination.
Then, begin recording the pressure-measuring device readings. These
pressure measurements shall be taken over a sampling period of
sufficiently long duration to ensure representative readings at
each traverse point. If the pressure measurements are determined
from visual readings of the pressure device or display, allow
sufficient time to observe the pulsation in the readings to obtain
a sight-weighted average, which is then recorded manually. If an
automated data acquisition system (e.g., data logger,
computer-based data recorder, strip chart recorder) is used to
record the pressure measurements, obtain an integrated average of
all pressure readings at the traverse point. Stack or duct gas
temperature measurements shall be recorded, at a minimum, once at
each traverse point. Record all necessary data as shown in the
example field data form (Table 2G-3).
8.9.6 Alignment check. For manually operated probes, after the
required yaw angle and differential pressure and temperature
measurements have been made at each traverse point, verify (e.g.,
by visual inspection) that the yaw angle-measuring device has
remained in proper alignment with the reference scribe line or with
the rotational offset position established in section 8.3. If, for
a particular traverse point, the angle-measuring device is found to
be in proper alignment, proceed to the next traverse point;
otherwise, re-align the device and repeat the angle and
differential pressure measurements at the traverse point. In the
course of a traverse, if a mark used to properly align the
angle-measuring device (e.g., as described in section 18.1.1.1)
cannot be located, re-establish the alignment mark before
proceeding with the traverse.
8.10 Probe Plugging. Periodically check for plugging of the
pressure ports by observing the responses on the pressure
differential readouts. Plugging causes erratic results or sluggish
responses. Rotate the probe to determine whether the readouts
respond in the expected direction. If plugging is detected, correct
the problem and repeat the affected measurements.
8.11 Static Pressure. Measure the static pressure in the stack
or duct using the equipment described in section 6.7.
8.11.1 If a Type S probe is used for this measurement, position
the probe at or between any traverse point(s) and rotate the probe
until a null differential pressure reading is obtained. Disconnect
the tubing from one of the pressure ports; read and record the ΔP.
For pressure devices with one-directional scales, if a deflection
in the positive direction is noted with the negative side
disconnected, then the static pressure is positive. Likewise, if a
deflection in the positive direction is noted with the positive
side disconnected, then the static pressure is negative.
8.11.2 If a 3-D probe is used for this measurement, position the
probe at or between any traverse point(s) and rotate the probe
until a null differential pressure reading is obtained at P2-P3.
Rotate the probe 90°. Disconnect the P2 pressure side of the probe
and read the pressure P1-Pbar and record as the static pressure.
(Note: The spherical probe, specified in section 6.1.2 of Method
2F, is unable to provide this measurement and shall not be used to
take static pressure measurements.)
8.12 Atmospheric Pressure. Determine the atmospheric pressure at
the sampling elevation during each test run following the procedure
described in section 2.5 of Method 2.
8.13 Molecular Weight. Determine the stack or duct gas dry
molecular weight. For combustion processes or processes that emit
essentially CO2, O2, CO, and N2, use Method 3 or 3A. For processes
emitting essentially air, an analysis need not be conducted; use a
dry molecular weight of 29.0. Other methods may be used, if
approved by the Administrator.
8.14 Moisture. Determine the moisture content of the stack gas
using Method 4 or equivalent.
8.15 Data Recording and Calculations. Record all required data
on a form similar to Table 2G-3.
8.15.1 2-D probe calibration coefficient. When a Type S pitot
tube is used in the field, the appropriate calibration coefficient
as determined in section 10.6 shall be used to perform velocity
calculations. For calibrated Type S pitot tubes, the A-side
coefficient shall be used when the A-side of the tube faces the
flow, and the B-side coefficient shall be used when the B-side
faces the flow.
8.15.2 3-D calibration coefficient. When a 3-D probe is used to
collect data with this method, follow the provisions for the
calibration of 3-D probes in section 10.6 of Method 2F to obtain
the appropriate velocity calibration coefficient (F2 as derived
using Equation 2F-2 in Method 2F) corresponding to a pitch angle
position of 0°.
8.15.3 Calculations. Calculate the yaw-adjusted velocity at each
traverse point using the equations presented in section 12.2.
Calculate the test run average stack gas velocity by finding the
arithmetic average of the point velocity results in accordance with
sections 12.3 and 12.4, and calculate the stack gas volumetric flow
rate in accordance with section 12.5 or 12.6, as applicable.
9.0 Quality Control
9.1 Quality Control Activities. In conjunction with the yaw
angle determination and the pressure and temperature measurements
specified in section 8.9, the following quality control checks
should be performed.
9.1.1 Range of the differential pressure gauge. In accordance
with the specifications in section 6.4, ensure that the proper
differential pressure gauge is being used for the range of ΔP
values encountered. If it is necessary to change to a more
sensitive gauge, replace the gauge with a gauge calibrated
according to section 10.3.3, perform the leak check described in
section 8.4 and the zero check described in section 8.5, and repeat
the differential pressure and temperature readings at each traverse
point.
9.1.2 Horizontal stability check. For horizontal traverses of a
stack or duct, visually check that the probe shaft is maintained in
a horizontal position prior to taking a pressure reading.
Periodically, during a test run, the probe's horizontal stability
should be verified by placing a carpenter's level, a digital
inclinometer, or other angle-measuring device on the portion of the
probe sheath that extends outside of the test port. A comparable
check should be performed by automated systems.
10.0 Calibration
10.1 Wind Tunnel Qualification Checks. To qualify for use in
calibrating probes, a wind tunnel shall have the design features
specified in section 6.11 and satisfy the following qualification
criteria. The velocity pressure cross-check in section 10.1.1 and
axial flow verification in section 10.1.2 shall be performed before
the initial use of the wind tunnel and repeated immediately after
any alteration occurs in the wind tunnel's configuration, fans,
interior surfaces, straightening vanes, controls, or other
properties that could reasonably be expected to alter the flow
pattern or velocity stability in the tunnel. The owner or operator
of a wind tunnel used to calibrate probes according to this method
shall maintain records documenting that the wind tunnel meets the
requirements of sections 10.1.1 and 10.1.2 and shall provide these
records to the Administrator upon request.
10.1.1 Velocity pressure cross-check. To verify that the wind
tunnel produces the same velocity at the tested probe head as at
the calibration pitot tube impact port, perform the following
cross-check. Take three differential pressure measurements at the
fixed calibration pitot tube location, using the calibration pitot
tube specified in section 6.10, and take three measurements with
the calibration pitot tube at the wind tunnel calibration location,
as defined in section 3.21. Alternate the measurements between the
two positions. Perform this procedure at the lowest and highest
velocity settings at which the probes will be calibrated. Record
the values on a form similar to Table 2G-4. At each velocity
setting, the average velocity pressure obtained at the wind tunnel
calibration location shall be within ±2 percent or 2.5 mm H2O (0.01
in. H2O), whichever is less restrictive, of the average velocity
pressure obtained at the fixed calibration pitot tube location.
This comparative check shall be performed at 2.5-cm (1-in.), or
smaller, intervals across the full length, width, and depth (if
applicable) of the wind tunnel calibration location. If the
criteria are not met at every tested point, the wind tunnel
calibration location must be redefined, so that acceptable results
are obtained at every point. Include the results of the velocity
pressure cross-check in the calibration data section of the field
test report. (See section 16.1.4.)
10.1.2 Axial flow verification. The following procedures shall
be performed to demonstrate that there is fully developed axial
flow within the wind tunnel calibration location and at the
calibration pitot tube location. Two options are available to
conduct this check.
10.1.2.1 Using a calibrated 3-D probe. A probe that has been
previously calibrated in a wind tunnel with documented axial flow
(as defined in section 3.22) may be used to conduct this check.
Insert the calibrated 3-D probe into the wind tunnel test section
using the tested probe port. Following the procedures in sections
8.9 and 12.2 of Method 2F, determine the yaw and pitch angles at
all the point(s) in the test section where the velocity pressure
cross-check, as specified in section 10.1.1, is performed. This
includes all the points in the calibration location and the point
where the calibration pitot tube will be located. Determine the yaw
and pitch angles at each point. Repeat these measurements at the
highest and lowest velocities at which the probes will be
calibrated. Record the values on a form similar to Table 2G-5. Each
measured yaw and pitch angle shall be within ±3° of 0°. Exceeding
the limits indicates unacceptable flow in the test section. Until
the problem is corrected and acceptable flow is verified by
repetition of this procedure, the wind tunnel shall not be used for
calibration of probes. Include the results of the axial flow
verification in the calibration data section of the field test
report. (See section 16.1.4.)
10.1.2.2 Using alternative probes. Axial flow verification may
be performed using an uncalibrated prism-shaped 3-D probe (e.g., DA
or DAT probe) or an uncalibrated wedge probe. (Figure 2G-8
illustrates a typical wedge probe.) This approach requires use of
two ports: the tested probe port and a second port located 90° from
the tested probe port. Each port shall provide access to all the
points within the wind tunnel test section where the velocity
pressure cross-check, as specified in section 10.1.1, is conducted.
The probe setup shall include establishing a reference yaw-null
position on the probe sheath to serve as the location for
installing the angle-measuring device. Physical design features of
the DA, DAT, and wedge probes are relied on to determine the
reference position. For the DA or DAT probe, this reference
position can be determined by setting a digital inclinometer on the
flat facet where the P1 pressure port is located and then
identifying the rotational position on the probe sheath where a
second angle-measuring device would give the same angle reading.
The reference position on a wedge probe shaft can be determined
either geometrically or by placing a digital inclinometer on each
side of the wedge and rotating the probe until equivalent readings
are obtained. With the latter approach, the reference position is
the rotational position on the probe sheath where an
angle-measuring device would give a reading of 0°. After
installation of the angle-measuring device in the reference
yaw-null position on the probe sheath, determine the yaw angle from
the tested port. Repeat this measurement using the 90° offset port,
which provides the pitch angle of flow. Determine the yaw and pitch
angles at all the point(s) in the test section where the velocity
pressure cross-check, as specified in section 10.1.1, is performed.
This includes all the points in the wind tunnel calibration
location and the point where the calibration pitot tube will be
located. Perform this check at the highest and lowest velocities at
which the probes will be calibrated. Record the values on a form
similar to Table 2G-5. Each measured yaw and pitch angle shall be
within ±3° of 0°. Exceeding the limits indicates unacceptable flow
in the test section. Until the problem is corrected and acceptable
flow is verified by repetition of this procedure, the wind tunnel
shall not be used for calibration of probes. Include the results in
the probe calibration report.
10.1.3 Wind tunnel audits.
10.1.3.1 Procedure. Upon the request of the Administrator, the
owner or operator of a wind tunnel shall calibrate a 2-D audit
probe in accordance with the procedures described in sections 10.3
through 10.6. The calibration shall be performed at two velocities
that encompass the velocities typically used for this method at the
facility. The resulting calibration data shall be submitted to the
Agency in an audit test report. These results shall be compared by
the Agency to reference calibrations of the audit probe at the same
velocity settings obtained at two different wind tunnels.
10.1.3.2 Acceptance criterion. The audited tunnel's calibration
coefficient is acceptable if it is within ±3 percent of the
reference calibrations obtained at each velocity setting by one (or
both) of the wind tunnels. If the acceptance criterion is not met
at each calibration velocity setting, the audited wind tunnel shall
not be used to calibrate probes for use under this method until the
problems are resolved and acceptable results are obtained upon
completion of a subsequent audit.
10.2 Probe Inspection.
10.2.1 Type S probe. Before each calibration of a Type S probe,
verify that one leg of the tube is permanently marked A, and the
other, B. Carefully examine the pitot tube from the top, side, and
ends. Measure the angles (α1, α2, β1, and β2) and the dimensions (w
and z) illustrated in Figures 2-2 and 2-3 in Method 2. Also measure
the dimension A, as shown in the diagram in Table 2G-1, and the
external tubing diameter (dimension Dt, Figure 2-2b in Method 2).
For the purposes of this method, Dt shall be no less than 9.5 mm (
3/8 in.). The base-to-opening plane distances PA and PB in Figure
2-3 of Method 2 shall be equal, and the dimension A in Table 2G-1
should be between 2.10Dt and 3.00Dt. Record the inspection findings
and probe measurements on a form similar to Table CD2-1 of the
“Quality Assurance Handbook for Air Pollution Measurement Systems:
Volume III, Stationary Source-Specific Methods” (EPA/600/R-94/038c,
September 1994). For reference, this form is reproduced herein as
Table 2G-1. The pitot tube shall not be used under this method if
it fails to meet the specifications in this section and the
alignment specifications in section 6.1.1. All Type S probes used
to collect data with this method shall be calibrated according to
the procedures outlined in sections 10.3 through 10.6 below. During
calibration, each Type S pitot tube shall be configured in the same
manner as used, or planned to be used, during the field test,
including all components in the probe assembly (e.g., thermocouple,
probe sheath, sampling nozzle). Probe shaft extensions that do not
affect flow around the probe head need not be attached during
calibration.
10.2.2 3-D probe. If a 3-D probe is used to collect data with
this method, perform the pre-calibration inspection according to
procedures in Method 2F, section 10.2.
10.3 Pre-Calibration Procedures. Prior to calibration, a scribe
line shall have been placed on the probe in accordance with section
10.4. The yaw angle and velocity calibration procedures shall not
begin until the pre-test requirements in sections 10.3.1 through
10.3.4 have been met.
10.3.1 Perform the horizontal straightness check described in
section 8.2 on the probe assembly that will be calibrated in the
wind tunnel.
10.3.2 Perform a leak check in accordance with section 8.4.
10.3.3 Except as noted in section 10.3.3.3, calibrate all
differential pressure-measuring devices to be used in the probe
calibrations, using the following procedures. At a minimum,
calibrate these devices on each day that probe calibrations are
performed.
10.3.3.1 Procedure. Before each wind tunnel use, all
differential pressure-measuring devices shall be calibrated against
the reference device specified in section 6.4.3 using a common
pressure source. Perform the calibration at three reference
pressures representing 30, 60, and 90 percent of the full-scale
range of the pressure-measuring device being calibrated. For an
inclined-vertical manometer, perform separate calibrations on the
inclined and vertical portions of the measurement scale,
considering each portion of the scale to be a separate full-scale
range. [For example, for a manometer with a 0-to 2.5-cm H2O (0-to
1-in. H2O) inclined scale and a 2.5-to 12.7-cm H2O (1-to 5-in. H2O)
vertical scale, calibrate the inclined portion at 7.6, 15.2, and
22.9 mm H2O (0.3, 0.6, and 0.9 in. H2O), and calibrate the vertical
portion at 3.8, 7.6, and 11.4 cm H2O (1.5, 3.0, and 4.5 in. H2O).]
Alternatively, for the vertical portion of the scale, use three
evenly spaced reference pressures, one of which is equal to or
higher than the highest differential pressure expected in field
applications.
10.3.3.2 Acceptance criteria. At each pressure setting, the two
pressure readings made using the reference device and the
pressure-measuring device being calibrated shall agree to within ±2
percent of full scale of the device being calibrated or 0.5 mm H2O
(0.02 in. H2O), whichever is less restrictive. For an
inclined-vertical manometer, these requirements shall be met
separately using the respective full-scale upper limits of the
inclined and vertical portions of the scale. Differential
pressure-measuring devices not meeting the ±2 percent of full scale
or 0.5 mm H2O (0.02 in. H2O) calibration requirement shall not be
used.
10.3.3.3 Exceptions. Any precision manometer that meets the
specifications for a reference device in section 6.4.3 and that is
not used for field testing does not require calibration, but must
be leveled and zeroed before each wind tunnel use. Any pressure
device used exclusively for yaw nulling does not require
calibration, but shall be checked for responsiveness to rotation of
the probe prior to each wind tunnel use.
10.3.4 Calibrate digital inclinometers on each day of wind
tunnel or field testing (prior to beginning testing) using the
following procedures. Calibrate the inclinometer according to the
manufacturer's calibration procedures. In addition, use a
triangular block (illustrated in Figure 2G-9) with a known angle θ,
independently determined using a protractor or equivalent device,
between two adjacent sides to verify the inclinometer readings.
(Note: If other angle-measuring devices meeting the provisions of
section 6.2.3 are used in place of a digital inclinometer,
comparable calibration procedures shall be performed on such
devices.) Secure the triangular block in a fixed position. Place
the inclinometer on one side of the block (side A) to measure the
angle of inclination (R1). Repeat this measurement on the adjacent
side of the block (side B) using the inclinometer to obtain a
second angle reading (R2). The difference of the sum of the two
readings from 180° (i.e., 180°-R1-R2) shall be within ±2° of the
known angle, θ.
10.4 Placement of Reference Scribe Line. Prior to the first
calibration of a probe, a line shall be permanently inscribed on
the main probe sheath to serve as a reference mark for determining
yaw angles. Annex C in section 18 of this method gives a guideline
for placement of the reference scribe line.
10.4.1 This reference scribe line shall meet the specifications
in sections 6.1.5.1 and 6.1.5.3 of this method. To verify that the
alignment specification in section 6.1.5.3 is met, secure the probe
in a horizontal position and measure the rotational angle of each
scribe line and scribe line segment using an angle-measuring device
that meets the specifications in section 6.2.1 or 6.2.3. For any
scribe line that is longer than 30.5 cm (12 in.), check the line's
rotational position at 30.5-cm (12-in.) intervals. For each line
segment that is 12 in. or less in length, check the rotational
position at the two endpoints of the segment. To meet the alignment
specification in section 6.1.5.3, the minimum and maximum of all of
the rotational angles that are measured along the full length of
main probe must not differ by more than 2°. (Note: A short
reference scribe line segment [e.g., 15.2 cm (6 in.) or less in
length] meeting the alignment specifications in section 6.1.5.3 is
fully acceptable under this method. See section 18.1.1.1 of Annex A
for an example of a probe marking procedure, suitable for use with
a short reference scribe line.)
10.4.2 The scribe line should be placed on the probe first and
then its offset from the yaw-null position established (as
specified in section 10.5). The rotational position of the
reference scribe line relative to the yaw-null position of the
probe, as determined by the yaw angle calibration procedure in
section 10.5, is the reference scribe line rotational offset, RSLO.
The reference scribe line rotational offset shall be recorded and
retained as part of the probe's calibration record.
10.4.3 Scribe line for automated probes. A scribe line may not
be necessary for an automated probe system if a reference
rotational position of the probe is built into the probe system
design. For such systems, a “flat” (or comparable, clearly
identifiable physical characteristic) should be provided on the
probe casing or flange plate to ensure that the reference position
of the probe assembly remains in a vertical or horizontal position.
The rotational offset of the flat (or comparable, clearly
identifiable physical characteristic) needed to orient the
reference position of the probe assembly shall be recorded and
maintained as part of the automated probe system's
specifications.
10.5 Yaw Angle Calibration Procedure. For each probe used to
measure yaw angles with this method, a calibration procedure shall
be performed in a wind tunnel meeting the specifications in section
10.1 to determine the rotational position of the reference scribe
line relative to the probe's yaw-null position. This procedure
shall be performed on the main probe with all devices that will be
attached to the main probe in the field [such as thermocouples,
resistance temperature detectors (RTDs), or sampling nozzles] that
may affect the flow around the probe head. Probe shaft extensions
that do not affect flow around the probe head need not be attached
during calibration. At a minimum, this procedure shall include the
following steps.
10.5.1 Align and lock the angle-measuring device on the
reference scribe line. If a marking procedure (such as described in
section 18.1.1.1) is used, align the angle-measuring device on a
mark within ±1° of the rotational position of the reference scribe
line. Lock the angle-measuring device onto the probe sheath at this
position.
10.5.2 Zero the pressure-measuring device used for yaw
nulling.
10.5.3 Insert the probe assembly into the wind tunnel through
the entry port, positioning the probe's impact port at the
calibration location. Check the responsiveness of the
pressure-measurement device to probe rotation, taking corrective
action if the response is unacceptable.
10.5.4 Ensure that the probe is in a horizontal position, using
a carpenter's level.
10.5.5 Rotate the probe either clockwise or counterclockwise
until a yaw null [zero ΔP for a Type S probe or zero (P2-P3) for a
3-D probe] is obtained. If using a Type S probe with an attached
thermocouple, the direction of the probe rotation shall be such
that the thermocouple is located downstream of the probe pressure
ports at the yaw-null position.
10.5.6 Use the reading displayed by the angle-measuring device
at the yaw-null position to determine the magnitude of the
reference scribe line rotational offset, RSLO, as defined in
section 3.15. Annex D in section 18 of this method gives a
recommended procedure for determining the magnitude of RSLO with a
digital inclinometer and a second procedure for determining the
magnitude of RSLO with a protractor wheel and pointer device. Table
2G-6 gives an example data form and Table 2G-7 is a look-up table
with the recommended procedure. Procedures other than those
recommended in Annex D in section 18 may be used, if they can
determine RSLO to within 1° and are explained in detail in the
field test report. The algebraic sign of RSLO will either be
positive if the rotational position of the reference scribe line
(as viewed from the “tail” end of the probe) is clockwise, or
negative, if counterclockwise with respect to the probe's yaw-null
position. (This is illustrated in Figure 2G-10.)
10.5.7 The steps in sections 10.5.3 through 10.5.6 shall be
performed twice at each of the velocities at which the probe will
be calibrated (in accordance with section 10.6). Record the values
of RSLO.
10.5.8 The average of all of the RSLO values shall be documented
as the reference scribe line rotational offset for the probe.
10.5.9 Use of reference scribe line offset. The reference scribe
line rotational offset shall be used to determine the yaw angle of
flow in accordance with section 8.9.4.
10.6 Velocity Calibration Procedure. When a 3-D probe is used
under this method, follow the provisions for the calibration of 3-D
probes in section 10.6 of Method 2F to obtain the necessary
velocity calibration coefficients (F2 as derived using Equation
2F-2 in Method 2F) corresponding to a pitch angle position of 0°.
The following procedure applies to Type S probes. This procedure
shall be performed on the main probe and all devices that will be
attached to the main probe in the field (e.g., thermocouples, RTDs,
sampling nozzles) that may affect the flow around the probe head.
Probe shaft extensions that do not affect flow around the probe
head need not be attached during calibration. (Note: If a sampling
nozzle is part of the assembly, two additional requirements must be
satisfied before proceeding. The distance between the nozzle and
the pitot tube shall meet the minimum spacing requirement
prescribed in Method 2, and a wind tunnel demonstration shall be
performed that shows the probe's ability to yaw null is not
impaired when the nozzle is drawing sample.) To obtain velocity
calibration coefficient(s) for the tested probe, proceed as
follows.
10.6.1 Calibration velocities. The tester may calibrate the
probe at two nominal wind tunnel velocity settings of 18.3 m/sec
and 27.4 m/sec (60 ft/sec and 90 ft/sec) and average the results of
these calibrations, as described in sections 10.6.12 through
10.6.14, in order to generate the calibration coefficient, Cp. If
this option is selected, this calibration coefficient may be used
for all field applications where the velocities are 9.1 m/sec (30
ft/sec) or greater. Alternatively, the tester may customize the
probe calibration for a particular field test application (or for a
series of applications), based on the expected average
velocity(ies) at the test site(s). If this option is selected,
generate the calibration coefficients by calibrating the probe at
two nominal wind tunnel velocity settings, one of which is less
than or equal to and the other greater than or equal to the
expected average velocity(ies) for the field application(s), and
average the results as described in sections 10.6.12 through
10.6.14. Whichever calibration option is selected, the probe
calibration coefficient(s) obtained at the two nominal calibration
velocities shall meet the conditions specified in sections 10.6.12
through 10.6.14.
10.6.2 Connect the tested probe and calibration pitot tube to
their respective pressure-measuring devices. Zero the
pressure-measuring devices. Inspect and leak-check all pitot lines;
repair or replace them, if necessary. Turn on the fan, and allow
the wind tunnel air flow to stabilize at the first of the selected
nominal velocity settings.
10.6.3 Position the calibration pitot tube at its measurement
location (determined as outlined in section 6.11.4.3), and align
the tube so that its tip is pointed directly into the flow. Ensure
that the entry port surrounding the tube is properly sealed. The
calibration pitot tube may either remain in the wind tunnel
throughout the calibration, or be removed from the wind tunnel
while measurements are taken with the probe being calibrated.
10.6.4 Check the zero setting of each pressure-measuring
device.
10.6.5 Insert the tested probe into the wind tunnel and align it
so that the designated pressure port (e.g., either the A-side or
B-side of a Type S probe) is pointed directly into the flow and is
positioned within the wind tunnel calibration location (as defined
in section 3.21). Secure the probe at the 0° pitch angle position.
Ensure that the entry port surrounding the probe is properly
sealed.
10.6.6 Read the differential pressure from the calibration pitot
tube (ΔPstd), and record its value. Read the barometric pressure to
within ±2.5 mm Hg (±0.1 in. Hg) and the temperature in the wind
tunnel to within 0.6 °C (1 °F). Record these values on a data form
similar to Table 2G-8. Record the rotational speed of the fan or
indicator of wind tunnel velocity control (damper setting, variac
rheostat, etc.) and make no adjustment to fan speed or wind tunnel
velocity control between this observation and the Type S probe
reading.
10.6.7 After the tested probe's differential pressure gauges
have had sufficient time to stabilize, yaw null the probe (and then
rotate it back 90° for Type S probes), then obtain the differential
pressure reading (ΔP). Record the yaw angle and differential
pressure readings.
10.6.8 Take paired differential pressure measurements with the
calibration pitot tube and tested probe (according to sections
10.6.6 and 10.6.7). The paired measurements in each replicate can
be made either simultaneously (i.e., with both probes in the
wind tunnel) or by alternating the measurements of the two probes
(i.e., with only one probe at a time in the wind tunnel).
Adjustments made to the fan speed or other changes to the system
designed to change the air flow velocity of the wind tunnel between
observation of the calibration pitot tube (ΔPstd) and the Type S
pitot tube invalidates the reading and the observation must be
repeated.
10.6.9 Repeat the steps in sections 10.6.6 through 10.6.8 at the
same nominal velocity setting until three pairs of ΔP readings have
been obtained from the calibration pitot tube and the tested
probe.
10.6.10 Repeat the steps in sections 10.6.6 through 10.6.9 above
for the A-side and B-side of the Type S pitot tube. For a probe
assembly constructed such that its pitot tube is always used in the
same orientation, only one side of the pitot tube need be
calibrated (the side that will face the flow). However, the pitot
tube must still meet the alignment and dimension specifications in
section 6.1.1 and must have an average deviation (σ) value of 0.01
or less as provided in section 10.6.12.4.
10.6.11 Repeat the calibration procedures in sections 10.6.6
through 10.6.10 at the second selected nominal wind tunnel velocity
setting.
10.6.12 Perform the following calculations separately on the
A-side and B-side values.
10.6.12.1 Calculate a Cp value for each of the three replicates
performed at the lower velocity setting where the calibrations were
performed using Equation 2-2 in section 4.1.4 of Method 2.
10.6.12.2 Calculate the arithmetic average, Cp(avg-low), of the
three Cp values.
10.6.12.3 Calculate the deviation of each of the three
individual values of Cp from the A-side average Cp(avg-low) value
using Equation 2-3 in Method 2.
10.6.12.4 Calculate the average deviation (σ) of the three
individual Cp values from Cp(avg-low) using Equation 2-4 in Method
2. Use the Type S pitot tube only if the values of σ (side A) and σ
(side B) are less than or equal to 0.01. If both A-side and B-side
calibration coefficients are calculated, the absolute value of the
difference between Cp(avg-low) (side A) and Cp(avg-low) (side B)
must not exceed 0.01.
10.6.13 Repeat the calculations in section 10.6.12 using the
data obtained at the higher velocity setting to derive the
arithmetic Cp values at the higher velocity setting, Cp(avg-high),
and to determine whether the conditions in 10.6.12.4 are met by
both the A-side and B-side calibrations at this velocity
setting.
10.6.14 Use equation 2G-1 to calculate the percent difference of
the averaged Cp values at the two calibration velocities.
The
percent difference between the averaged Cp values shall not exceed
±3 percent. If the specification is met, average the A-side values
of Cp(avg-low) and Cp(avg-high) to produce a single A-side
calibration coefficient, Cp. Repeat for the B-side values if
calibrations were performed on that side of the pitot. If the
specification is not met, make necessary adjustments in the
selected velocity settings and repeat the calibration procedure
until acceptable results are obtained.
10.6.15 If the two nominal velocities used in the calibration
were 18.3 and 27.4 m/sec (60 and 90 ft/sec), the average Cp from
section 10.6.14 is applicable to all velocities 9.1 m/sec (30
ft/sec) or greater. If two other nominal velocities were used in
the calibration, the resulting average Cp value shall be applicable
only in situations where the velocity calculated using the
calibration coefficient is neither less than the lower nominal
velocity nor greater than the higher nominal velocity.
10.7 Recalibration. Recalibrate the probe using the procedures
in section 10 either within 12 months of its first field use after
its most recent calibration or after 10 field tests (as defined in
section 3.3), whichever occurs later. In addition, whenever there
is visible damage to the probe head, the probe shall be
recalibrated before it is used again.
10.8 Calibration of pressure-measuring devices used in the
field. Before its initial use in a field test, calibrate each
pressure-measuring device (except those used exclusively for yaw
nulling) using the three-point calibration procedure described in
section 10.3.3. The device shall be recalibrated according to the
procedure in section 10.3.3 no later than 90 days after its first
field use following its most recent calibration. At the discretion
of the tester, more frequent calibrations (e.g., after a field
test) may be performed. No adjustments, other than adjustments to
the zero setting, shall be made to the device between
calibrations.
10.8.1 Post-test calibration check. A single-point calibration
check shall be performed on each pressure-measuring device after
completion of each field test. At the discretion of the tester,
more frequent single-point calibration checks (e.g., after one or
more field test runs) may be performed. It is recommended that the
post-test check be performed before leaving the field test site.
The check shall be performed at a pressure between 50 and 90
percent of full scale by taking a common pressure reading with the
tested probe and a reference pressure-measuring device (as
described in section 6.4.4) or by challenging the tested device
with a reference pressure source (as described in section 6.4.4) or
by performing an equivalent check using a reference device approved
by the Administrator.
10.8.2 Acceptance criterion. At the selected pressure setting,
the pressure readings made using the reference device and the
tested device shall agree to within ±3 percent of full scale of the
tested device or 0.8 mm H2O (0.03 in. H2O), whichever is less
restrictive. If this specification is met, the test data collected
during the field test are valid. If the specification is not met,
all test data collected since the last successful calibration or
calibration check are invalid and shall be repeated using a
pressure-measuring device with a current, valid calibration. Any
device that fails the calibration check shall not be used in a
field test until a successful recalibration is performed according
to the procedures in section 10.3.3.
10.9 Temperature Gauges. Same as Method 2, section 4.3. The
alternative thermocouple calibration procedures outlined in
Emission Measurement Center (EMC) Approved Alternative Method
(ALT-011) “Alternative Method 2 Thermocouple Calibration Procedure”
may be performed. Temperature gauges shall be calibrated no more
than 30 days prior to the start of a field test or series of field
tests and recalibrated no more than 30 days after completion of a
field test or series of field tests.
10.10 Barometer. Same as Method 2, section 4.4. The barometer
shall be calibrated no more than 30 days prior to the start of a
field test or series of field tests.
11.0 Analytical Procedure
Sample collection and analysis are concurrent for this method
(see section 8.0).
12.0 Data Analysis and Calculations
These calculations use the measured yaw angle and the
differential pressure and temperature measurements at individual
traverse points to derive the near-axial flue gas velocity (va(i))
at each of those points. The near-axial velocity values at all
traverse points that comprise a full stack or duct traverse are
then averaged to obtain the average near-axial stack or duct gas
velocity (va(avg)).
12.1 Nomenclature A = Cross-sectional area of stack or duct at the
test port location, m 2 (ft 2). Bws = Water vapor in the gas stream
(from Method 4 or alternative), proportion by volume. Cp = Pitot
tube calibration coefficient, dimensionless. F2(i) = 3-D probe
velocity coefficient at 0 pitch, applicable at traverse point i. Kp
= Pitot tube constant, for the metric
system, and for the English
system. Md = Molecular weight of stack or duct gas, dry basis (see
section 8.13), g/g-mole (lb/lb-mole). Ms = Molecular weight of
stack or duct gas, wet basis, g/g-mole (lb/lb-mole). Pbar = Barometric
pressure at velocity measurement site, mm Hg (in. Hg). Pg = Stack
or duct static pressure, mm H2O (in. H2O). Ps = Absolute stack or
duct pressure, mm Hg (in. Hg), Pstd = Standard
absolute pressure, 760 mm Hg (29.92 in. Hg). 13.6 = Conversion from
mm H2O (in. H2O) to mm Hg (in. Hg). Qsd = Average dry-basis
volumetric stack or duct gas flow rate corrected to standard
conditions, dscm/hr (dscf/hr). Qsw = Average wet-basis volumetric
stack or duct gas flow rate corrected to standard conditions,
wscm/hr (wscf/hr). ts(i) = Stack or duct temperature, °C (°F), at
traverse point i. Ts(i) = Absolute stack or duct temperature, °K
(°R), at traverse point i. for the metric
system, and for the English
system. Ts(avg) = Average absolute stack or duct gas temperature
across all traverse points. Tstd = Standard absolute temperature,
293 °K (528 °R). va(i) = Measured stack or duct gas impact
velocity, m/sec (ft/sec), at traverse point i. va(avg) = Average
near-axial stack or duct gas velocity, m/sec (ft/sec) across all
traverse points. ΔPi = Velocity head (differential pressure) of
stack or duct gas, mm H2O (in. H2O), applicable at traverse point
i. (P1-P2) = Velocity head (differential pressure) of stack or duct
gas measured by a 3-D probe, mm H2O (in. H2O), applicable at
traverse point i. 3,600 = Conversion factor, sec/hr. 18.0 =
Molecular weight of water, g/g-mole (lb/lb-mole). θy(i) = Yaw angle
of the flow velocity vector, at traverse point i. n = Number of
traverse points.
12.2 Traverse Point Velocity Calculations. Perform the following
calculations from the measurements obtained at each traverse
point.
12.2.1 Selection of calibration coefficient. Select the
calibration coefficient as described in section 10.6.1.
12.2.2 Near-axial traverse point velocity. When using a Type S
probe, use the following equation to calculate the traverse point
near-axial velocity (va(i)) from the differential pressure (ΔPi),
yaw angle (θy(i)), absolute stack or duct standard temperature
(Ts(i)) measured at traverse point i, the absolute stack or duct
pressure (Ps), and molecular weight (Ms).
Use the
following equation when using a 3-D probe.
12.2.3 Handling multiple measurements at a traverse point. For
pressure or temperature devices that take multiple measurements at
a traverse point, the multiple measurements (or where applicable,
their square roots) may first be averaged and the resulting average
values used in the equations above. Alternatively, the individual
measurements may be used in the equations above and the resulting
calculated values may then be averaged to obtain a single traverse
point value. With either approach, all of the individual
measurements recorded at a traverse point must be used in
calculating the applicable traverse point value.
12.3 Average Near-Axial Velocity in Stack or Duct. Use the
reported traverse point near-axial velocity in the following
equation.
12.4 Acceptability of Results. The acceptability provisions in
section 12.4 of Method 2F apply to 3-D probes used under Method 2G.
The following provisions apply to Type S probes. For Type S probes,
the test results are acceptable and the calculated value of va(avg)
may be reported as the average near-axial velocity for the test run
if the conditions in either section 12.4.1 or 12.4.2 are met.
12.4.1 The average calibration coefficient Cp used in Equation
2G-6 was generated at nominal velocities of 18.3 and 27.4 m/sec (60
and 90 ft/sec) and the value of va(avg) calculated using Equation
2G-8 is greater than or equal to 9.1 m/sec (30 ft/sec).
12.4.2 The average calibration coefficient Cp used in Equation
2G-6 was generated at nominal velocities other than 18.3 or 27.4
m/sec (60 or 90 ft/sec) and the value of va(avg) calculated using
Equation 2G-8 is greater than or equal to the lower nominal
velocity and less than or equal to the higher nominal velocity used
to derive the average Cp.
12.4.3 If the conditions in neither section 12.4.1 nor section
12.4.2 are met, the test results obtained from Equation 2G-8 are
not acceptable, and the steps in sections 12.2 and 12.3 must be
repeated using an average calibration coefficient Cp that satisfies
the conditions in section 12.4.1 or 12.4.2.
12.5 Average Gas Volumetric Flow Rate in Stack or Duct (Wet
Basis). Use the following equation to compute the average
volumetric flow rate on a wet basis.
12.6 Average Gas Volumetric Flow Rate in Stack or Duct (Dry
Basis). Use the following equation to compute the average
volumetric flow rate on a dry basis.
16.1 Field Test Reports. Field test reports shall be submitted
to the Agency according to applicable regulatory requirements.
Field test reports should, at a minimum, include the following
elements.
16.1.1 Description of the source. This should include the name
and location of the test site, descriptions of the process tested,
a description of the combustion source, an accurate diagram of
stack or duct cross-sectional area at the test site showing the
dimensions of the stack or duct, the location of the test ports,
and traverse point locations and identification numbers or codes.
It should also include a description and diagram of the stack or
duct layout, showing the distance of the test location from the
nearest upstream and downstream disturbances and all structural
elements (including breachings, baffles, fans, straighteners, etc.)
affecting the flow pattern. If the source and test location
descriptions have been previously submitted to the Agency in a
document (e.g., a monitoring plan or test plan), referencing the
document in lieu of including this information in the field test
report is acceptable.
16.1.2 Field test procedures. These should include a description
of test equipment and test procedures. Testing conventions, such as
traverse point numbering and measurement sequence (e.g., sampling
from center to wall, or wall to center), should be clearly stated.
Test port identification and directional reference for each test
port should be included on the appropriate field test data
sheets.
16.1.3 Field test data.
16.1.3.1 Summary of results. This summary should include the
dates and times of testing, and the average near-axial gas velocity
and the average flue gas volumetric flow results for each run and
tested condition.
16.1.3.2 Test data. The following values for each traverse point
should be recorded and reported:
(a) Differential pressure at traverse point i (ΔPi)
(b) Stack or duct temperature at traverse point i (ts(i))
(c) Absolute stack or duct temperature at traverse point i
(Ts(i))
(d) Yaw angle at traverse point i (θy(i))
(e) Stack gas near-axial velocity at traverse point i
(va(i))
16.1.3.3 The following values should be reported once per
run:
(a) Water vapor in the gas stream (from Method 4 or
alternative), proportion by volume (Bws), measured at the frequency
specified in the applicable regulation
(b) Molecular weight of stack or duct gas, dry basis (Md)
(c) Molecular weight of stack or duct gas, wet basis (Ms)
(d) Stack or duct static pressure (Pg)
(e) Absolute stack or duct pressure (Ps)
(f) Carbon dioxide concentration in the flue gas, dry basis (%d
CO2)
(g) Oxygen concentration in the flue gas, dry basis (%d O2)
(h) Average near-axial stack or duct gas velocity (va(avg))
across all traverse points
(i) Gas volumetric flow rate corrected to standard conditions,
dry or wet basis as required by the applicable regulation (Qsd or
Qsw)
16.1.3.4 The following should be reported once per complete set
of test runs:
(a) Cross-sectional area of stack or duct at the test location
(A)
(b) Pitot tube calibration coefficient (Cp)
(c) Measurement system response time (sec)
(d) Barometric pressure at measurement site (Pbar)
16.1.4 Calibration data. The field test report should include
calibration data for all probes and test equipment used in the
field test. At a minimum, the probe calibration data reported to
the Agency should include the following:
(a) Date of calibration
(b) Probe type
(c) Probe identification number(s) or code(s)
(d) Probe inspection sheets
(e) Pressure measurements and calculations used to obtain
calibration coefficients in accordance with section 10.6 of this
method
(f) Description and diagram of wind tunnel used for the
calibration, including dimensions of cross-sectional area and
position and size of the test section
(g) Documentation of wind tunnel qualification tests performed
in accordance with section 10.1 of this method
16.1.5 Quality assurance. Specific quality assurance and quality
control procedures used during the test should be described.
17.0 Bibliography.
(1) 40 CFR Part 60, Appendix A, Method 1 - Sample and velocity
traverses for stationary sources.
(2) 40 CFR Part 60, Appendix A, Method 2 - Determination of
stack gas velocity and volumetric flow rate (Type S pitot tube)
.
(3) 40 CFR Part 60, Appendix A, Method 2F - Determination of
stack gas velocity and volumetric flow rate with three-dimensional
probes.
(4) 40 CFR Part 60, Appendix A, Method 2H - Determination of
stack gas velocity taking into account velocity decay near the
stack wall.
(5) 40 CFR Part 60, Appendix A, Method 3 - Gas analysis for
carbon dioxide, oxygen, excess air, and dry molecular weight.
(6) 40 CFR Part 60, Appendix A, Method 3A - Determination of
oxygen and carbon dioxide concentrations in emissions from
stationary sources (instrumental analyzer procedure).
(7) 40 CFR Part 60, Appendix A, Method 4 - Determination of
moisture content in stack gases.
(8) Emission Measurement Center (EMC) Approved Alternative
Method (ALT-011) “Alternative Method 2 Thermocouple Calibration
Procedure.”
(9) Electric Power Research Institute, Interim Report EPRI
TR-106698, “Flue Gas Flow Rate Measurement Errors,” June 1996.
(10) Electric Power Research Institute, Final Report EPRI
TR-108110, “Evaluation of Heat Rate Discrepancy from Continuous
Emission Monitoring Systems,” August 1997.
(11) Fossil Energy Research Corporation, Final Report, “Velocity
Probe Tests in Non-axial Flow Fields,” November 1998, Prepared for
the U.S. Environmental Protection Agency.
(12) Fossil Energy Research Corporation, “Additional Swirl
Tunnel Tests: E-DAT and T-DAT Probes,” February 24, 1999, Technical
Memorandum Prepared for U.S. Environmental Protection Agency, P.O.
No. 7W-1193-NALX.
(13) Massachusetts Institute of Technology, Report WBWT-TR-1317,
“Calibration of Eight Wind Speed Probes Over a Reynolds Number
Range of 46,000 to 725,000 Per Foot, Text and Summary Plots,” Plus
appendices, October 15, 1998, Prepared for The Cadmus Group,
Inc.
(14) National Institute of Standards and Technology, Special
Publication 250, “NIST Calibration Services Users Guide 1991,”
Revised October 1991, U.S. Department of Commerce, p. 2.
(15) National Institute of Standards and Technology, 1998,
“Report of Special Test of Air Speed Instrumentation, Four Prandtl
Probes, Four S-Type Probes, Four French Probes, Four Modified Kiel
Probes,” Prepared for the U.S. Environmental Protection Agency
under IAG #DW13938432-01-0.
(16) National Institute of Standards and Technology, 1998,
“Report of Special Test of Air Speed In-strumentation, Five
Autoprobes,” Prepared for the U.S. Environmental Protection Agency
under IAG #DW13938432-01-0.
(17) National Institute of Standards and Technology, 1998,
“Report of Special Test of Air Speed Instrumentation, Eight
Spherical Probes,” Prepared for the U.S. Environmental Protection
Agency under IAG #DW13938432-01-0.
(18) National Institute of Standards and Technology, 1998,
“Report of Special Test of Air Speed Instrumentation, Four DAT
Probes, “ Prepared for the U.S. Environmental Protection Agency
under IAG #DW13938432-01-0.
(19) Norfleet, S.K., “An Evaluation of Wall Effects on Stack
Flow Velocities and Related Overestimation Bias in EPA's Stack Flow
Reference Methods,” EPRI CEMS User's Group Meeting, New Orleans,
Louisiana, May 13-15, 1998.
(20) Page, J.J., E.A. Potts, and R.T. Shigehara, “3-D Pitot Tube
Calibration Study,” EPA Contract No. 68D10009, Work Assignment No.
I-121, March 11, 1993.
(21) Shigehara, R.T., W.F. Todd, and W.S. Smith, “Significance
of Errors in Stack Sampling Measurements,” Presented at the Annual
Meeting of the Air Pollution Control Association, St. Louis,
Missouri, June 1419, 1970.
(22) The Cadmus Group, Inc., May 1999, “EPA Flow Reference
Method Testing and Analysis: Findings Report,”
EPA/430-R-99-009.
(23) The Cadmus Group, Inc., 1998, “EPA Flow Reference Method
Testing and Analysis: Data Report, Texas Utilities, DeCordova Steam
Electric Station, Volume I: Test Description and Appendix A (Data
Distribution Package),” EPA/430-R-98-015a.
(24) The Cadmus Group, Inc., 1998, “EPA Flow Reference Method
Testing and Analysis: Data Report, Texas Utilities, Lake Hubbard
Steam Electric Station, Volume I: Test Description and Appendix A
(Data Distribution Package),” EPA/430-R-98-017a.
(25) The Cadmus Group, Inc., 1998, “EPA Flow Reference Method
Testing and Analysis: Data Report, Pennsylvania Electric Co.,
G.P.U. Genco Homer City Station: Unit 1, Volume I: Test Description
and Appendix A (Data Distribution Package),” EPA/430-R-98-018a.
(26) The Cadmus Group, Inc., 1997, “EPA Flow Reference Method
Testing and Analysis: Wind Tunnel Experimental Results,”
EPA/430-R-97-013.
18.0 Annexes
Annex A, C, and D describe recommended procedures for meeting
certain provisions in sections 8.3, 10.4, and 10.5 of this method.
Annex B describes procedures to be followed when using the
protractor wheel and pointer assembly to measure yaw angles, as
provided under section 8.9.1.
18.1 Annex A - Rotational Position Check. The following are
recommended procedures that may be used to satisfy the rotational
position check requirements of section 8.3 of this method and to
determine the angle-measuring device rotational offset (RADO).
18.1.1 Rotational position check with probe outside stack. Where
physical constraints at the sampling location allow full assembly
of the probe outside the stack and insertion into the test port,
the following procedures should be performed before the start of
testing. Two angle-measuring devices that meet the specifications
in section 6.2.1 or 6.2.3 are required for the rotational position
check. An angle measuring device whose position can be
independently adjusted (e.g., by means of a set screw) after being
locked into position on the probe sheath shall not be used for this
check unless the independent adjustment is set so that the device
performs exactly like a device without the capability for
independent adjustment. That is, when aligned on the probe such a
device must give the same reading as a device that does not have
the capability of being independently adjusted. With the fully
assembled probe (including probe shaft extensions, if any) secured
in a horizontal position, affix one yaw angle-measuring device to
the probe sheath and lock it into position on the reference scribe
line specified in section 6.1.5.1. Position the second
angle-measuring device using the procedure in section 18.1.1.1 or
18.1.1.2.
18.1.1.1 Marking procedure. The procedures in this section
should be performed at each location on the fully assembled probe
where the yaw angle-measuring device will be mounted during the
velocity traverse. Place the second yaw angle-measuring device on
the main probe sheath (or extension) at the position where a yaw
angle will be measured during the velocity traverse. Adjust the
position of the second angle-measuring device until it indicates
the same angle (±1°) as the reference device, and affix the second
device to the probe sheath (or extension). Record the angles
indicated by the two angle-measuring devices on a form similar to
table 2G-2. In this position, the second angle-measuring device is
considered to be properly positioned for yaw angle measurement.
Make a mark, no wider than 1.6 mm ( 1/16 in.), on the probe sheath
(or extension), such that the yaw angle-measuring device can be
re-affixed at this same properly aligned position during the
velocity traverse.
18.1.1.2 Procedure for probe extensions with scribe lines. If,
during a velocity traverse the angle-measuring device will be
affixed to a probe extension having a scribe line as specified in
section 6.1.5.2, the following procedure may be used to align the
extension's scribe line with the reference scribe line instead of
marking the extension as described in section 18.1.1.1. Attach the
probe extension to the main probe. Align and lock the second
angle-measuring device on the probe extension's scribe line. Then,
rotate the extension until both measuring devices indicate the same
angle (±1°). Lock the extension at this rotational position. Record
the angles indicated by the two angle-measuring devices on a form
similar to table 2G-2. An angle-measuring device may be aligned at
any position on this scribe line during the velocity traverse, if
the scribe line meets the alignment specification in section
6.1.5.3.
18.1.1.3 Post-test rotational position check. If the fully
assembled probe includes one or more extensions, the following
check should be performed immediately after the completion of a
velocity traverse. At the discretion of the tester, additional
checks may be conducted after completion of testing at any sample
port. Without altering the alignment of any of the components of
the probe assembly used in the velocity traverse, secure the fully
assembled probe in a horizontal position. Affix an angle-measuring
device at the reference scribe line specified in section 6.1.5.1.
Use the other angle-measuring device to check the angle at each
location where the device was checked prior to testing. Record the
readings from the two angle-measuring devices.
18.1.2 Rotational position check with probe in stack. This
section applies only to probes that, due to physical constraints,
cannot be inserted into the test port as fully assembled with all
necessary extensions needed to reach the inner-most traverse
point(s).
18.1.2.1 Perform the out-of-stack procedure in section 18.1.1 on
the main probe and any attached extensions that will be initially
inserted into the test port.
18.1.2.2 Use the following procedures to perform additional
rotational position check(s) with the probe in the stack, each time
a probe extension is added. Two angle-measuring devices are
required. The first of these is the device that was used to measure
yaw angles at the preceding traverse point, left in its properly
aligned measurement position. The second angle-measuring device is
positioned on the added probe extension. Use the applicable
procedures in section 18.1.1.1 or 18.1.1.2 to align, adjust, lock,
and mark (if necessary) the position of the second angle-measuring
device to within ±1° of the first device. Record the readings of
the two devices on a form similar to Table 2G-2.
18.1.2.3 The procedure in section 18.1.2.2 should be performed
at the first port where measurements are taken. The procedure
should be repeated each time a probe extension is re-attached at a
subsequent port, unless the probe extensions are designed to be
locked into a mechanically fixed rotational position (e.g., through
use of interlocking grooves), which can be reproduced from port to
port as specified in section 8.3.5.2.
18.2 Annex B - Angle Measurement Protocol for Protractor Wheel
and Pointer Device. The following procedure shall be used when a
protractor wheel and pointer assembly, such as the one described in
section 6.2.2 and illustrated in Figure 2G-5 is used to measure the
yaw angle of flow. With each move to a new traverse point, unlock,
re-align, and re-lock the probe, angle-pointer collar, and
protractor wheel to each other. At each such move, particular
attention is required to ensure that the scribe line on the angle
pointer collar is either aligned with the reference scribe line on
the main probe sheath or is at the rotational offset position
established under section 8.3.1. The procedure consists of the
following steps:
18.2.1 Affix a protractor wheel to the entry port for the test
probe in the stack or duct.
18.2.2 Orient the protractor wheel so that the 0° mark
corresponds to the longitudinal axis of the stack or duct. For
stacks, vertical ducts, or ports on the side of horizontal ducts,
use a digital inclinometer meeting the specifications in section
6.2.1 to locate the 0° orientation. For ports on the top or bottom
of horizontal ducts, identify the longitudinal axis at each test
port and permanently mark the duct to indicate the 0° orientation.
Once the protractor wheel is properly aligned, lock it into
position on the test port.
18.2.3 Move the pointer assembly along the probe sheath to the
position needed to take measurements at the first traverse point.
Align the scribe line on the pointer collar with the reference
scribe line or at the rotational offset position established under
section 8.3.1. Maintaining this rotational alignment, lock the
pointer device onto the probe sheath. Insert the probe into the
entry port to the depth needed to take measurements at the first
traverse point.
18.2.4 Perform the yaw angle determination as specified in
sections 8.9.3 and 8.9.4 and record the angle as shown by the
pointer on the protractor wheel. Then, take velocity pressure and
temperature measurements in accordance with the procedure in
section 8.9.5. Perform the alignment check described in section
8.9.6.
18.2.5 After taking velocity pressure measurements at that
traverse point, unlock the probe from the collar and slide the
probe through the collar to the depth needed to reach the next
traverse point.
18.2.6 Align the scribe line on the pointer collar with the
reference scribe line on the main probe or at the rotational offset
position established under section 8.3.1. Lock the collar onto the
probe.
18.2.7 Repeat the steps in sections 18.2.4 through 18.2.6 at the
remaining traverse points accessed from the current stack or duct
entry port.
18.2.8 After completing the measurement at the last traverse
point accessed from a port, verify that the orientation of the
protractor wheel on the test port has not changed over the course
of the traverse at that port. For stacks, vertical ducts, or ports
on the side of horizontal ducts, use a digital inclinometer meeting
the specifications in section 6.2.1 to check the rotational
position of the 0° mark on the protractor wheel. For ports on the
top or bottom of horizontal ducts, observe the alignment of the
angle wheel 0° mark relative to the permanent 0° mark on the duct
at that test port. If these observed comparisons exceed ±2° of 0°,
all angle and pressure measurements taken at that port since the
protractor wheel was last locked into position on the port shall be
repeated.
18.2.9 Move to the next stack or duct entry port and repeat the
steps in sections 18.2.1 through 18.2.8.
18.3 Annex C - Guideline for Reference Scribe Line Placement.
Use of the following guideline is recommended to satisfy the
requirements of section 10.4 of this method. The rotational
position of the reference scribe line should be either 90° or 180°
from the probe's impact pressure port. For Type-S probes, place
separate scribe lines, on opposite sides of the probe sheath, if
both the A and B sides of the pitot tube are to be used for yaw
angle measurements.
18.4 Annex D - Determination of Reference Scribe Line Rotational
Offset. The following procedures are recommended for determining
the magnitude and sign of a probe's reference scribe line
rotational offset, RSLO. Separate procedures are provided for two
types of angle-measuring devices: digital inclinometers and
protractor wheel and pointer assemblies.
18.4.1 Perform the following procedures on the main probe with
all devices that will be attached to the main probe in the field
[such as thermocouples, resistance temperature detectors (RTDs), or
sampling nozzles] that may affect the flow around the probe head.
Probe shaft extensions that do not affect flow around the probe
head need not be attached during calibration.
18.4.2 The procedures below assume that the wind tunnel duct
used for probe calibration is horizontal and that the flow in the
calibration wind tunnel is axial as determined by the axial flow
verification check described in section 10.1.2. Angle-measuring
devices are assumed to display angles in alternating 0° to 90° and
90° to 0° intervals. If angle-measuring devices with other readout
conventions are used or if other calibration wind tunnel duct
configurations are used, make the appropriate calculational
corrections. For Type-S probes, calibrate the A-side and B-sides
separately, using the appropriate scribe line (see section 18.3,
above), if both the A and B sides of the pitot tube are to be used
for yaw angle determinations.
18.4.2.1 Position the angle-measuring device in accordance with
one of the following procedures.
18.4.2.1.1 If using a digital inclinometer, affix the calibrated
digital inclinometer to the probe. If the digital inclinometer can
be independently adjusted after being locked into position on the
probe sheath (e.g., by means of a set screw), the independent
adjustment must be set so that the device performs exactly like a
device without the capability for independent adjustment. That is,
when aligned on the probe the device must give the same readings as
a device that does not have the capability of being independently
adjusted. Either align it directly on the reference scribe line or
on a mark aligned with the scribe line determined according to the
procedures in section 18.1.1.1. Maintaining this rotational
alignment, lock the digital inclinometer onto the probe sheath.
18.4.2.1.2 If using a protractor wheel and pointer device,
orient the protractor wheel on the test port so that the 0° mark is
aligned with the longitudinal axis of the wind tunnel duct.
Maintaining this alignment, lock the wheel into place on the wind
tunnel test port. Align the scribe line on the pointer collar with
the reference scribe line or with a mark aligned with the reference
scribe line, as determined under section 18.1.1.1. Maintaining this
rotational alignment, lock the pointer device onto the probe
sheath.
18.4.2.2 Zero the pressure-measuring device used for yaw
nulling.
18.4.2.3 Insert the probe assembly into the wind tunnel through
the entry port, positioning the probe's impact port at the
calibration location. Check the responsiveness of the
pressure-measuring device to probe rotation, taking corrective
action if the response is unacceptable.
18.4.2.4 Ensure that the probe is in a horizontal position using
a carpenter's level.
18.4.2.5 Rotate the probe either clockwise or counterclockwise
until a yaw null [zero ΔP for a Type S probe or zero (P2-P3) for a
3-D probe] is obtained. If using a Type S probe with an attached
thermocouple, the direction of the probe rotation shall be such
that the thermocouple is located downstream of the probe pressure
ports at the yaw-null position.
18.4.2.6 Read and record the value of θnull, the angle indicated
by the angle-measuring device at the yaw-null position. Record the
angle reading on a form similar to Table 2G-6. Do not associate an
algebraic sign with this reading.
18.4.2.7 Determine the magnitude and algebraic sign of the
reference scribe line rotational offset, RSLO. The magnitude of
RSLO will be equal to either θnull or (90°−θnull), depending on the
type of probe being calibrated and the type of angle-measuring
device used. (See Table 2G-7 for a summary.) The algebraic sign of
RSLO will either be positive if the rotational position of the
reference scribe line is clockwise or negative if counterclockwise
with respect to the probe's yaw-null position. Figure 2G-10
illustrates how the magnitude and sign of RSLO are determined.
18.4.2.8 Perform the steps in sections 18.3.2.3 through 18.3.2.7
twice at each of the two calibration velocities selected for the
probe under section 10.6. Record the values of RSLO in a form
similar to Table 2G-6.
18.4.2.9 The average of all RSLO values is the reference scribe
line rotational offset for the probe.
Method 2H -
Determination of Stack Gas Velocity Taking Into Account Velocity
Decay Near the Stack Wall 1.0 Scope and Application
1.1 This method is applicable in conjunction with Methods 2, 2F,
and 2G (40 CFR Part 60, Appendix A) to account for velocity decay
near the wall in circular stacks and ducts.
1.2 This method is not applicable for testing stacks and ducts
less than 3.3 ft (1.0 m) in diameter.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A wall effects adjustment factor is determined. It is used
to adjust the average stack gas velocity obtained under Method 2,
2F, or 2G of this appendix to take into account velocity decay near
the stack or duct wall.
2.2 The method contains two possible procedures: a calculational
approach which derives an adjustment factor from velocity
measurements and a default procedure which assigns a generic
adjustment factor based on the construction of the stack or
duct.
2.2.1 The calculational procedure derives a wall effects
adjustment factor from velocity measurements taken using Method 2,
2F, or 2G at 16 (or more) traverse points specified under Method 1
of this appendix and a total of eight (or more) wall effects
traverse points specified under this method. The calculational
procedure based on velocity measurements is not applicable for
horizontal circular ducts where build-up of particulate matter or
other material in the bottom of the duct is present.
2.2.2 A default wall effects adjustment factor of 0.9900 for
brick and mortar stacks and 0.9950 for all other types of stacks
and ducts may be used without taking wall effects measurements in a
stack or duct.
2.3 When the calculational procedure is conducted as part of a
relative accuracy test audit (RATA) or other multiple-run test
procedure, the wall effects adjustment factor derived from a single
traverse (i.e., single RATA run) may be applied to all runs of the
same RATA without repeating the wall effects measurements.
Alternatively, wall effects adjustment factors may be derived for
several traverses and an average wall effects adjustment factor
applied to all runs of the same RATA.
3.0 Definitions.
3.1 Complete wall effects traverse means a traverse in
which measurements are taken at drem (see section 3.3) and at 1-in.
intervals in each of the four Method 1 equal-area sectors closest
to the wall, beginning not farther than 4 in. (10.2 cm) from the
wall and extending either (1) across the entire width of the Method
1 equal-area sector or (2) for stacks or ducts where this width
exceeds 12 in. (30.5 cm) (i.e., stacks or ducts greater than or
equal to 15.6 ft [4.8 m] in diameter), to a distance of not less
than 12 in. (30.5 cm) from the wall. Note: Because this method
specifies that measurements must be taken at whole number multiples
of 1 in. from a stack or duct wall, for clarity numerical
quantities in this method are expressed in English units followed
by metric units in parentheses. To enhance readability, hyphenated
terms such as “1-in. intervals” or “1-in. incremented,” are
expressed in English units only.
3.2 dlast Depending on context, dlast means either
(1) the distance from the wall of the last 1-in. incremented wall
effects traverse point or (2) the traverse point located at that
distance (see Figure 2H-2).
3.3 drem Depending on context, drem means either
(1) the distance from the wall of the centroid of the area between
dlast and the interior edge of the Method 1 equal-area
sector closest to the wall or (2) the traverse point located at
that distance (see Figure 2H-2).
3.4 “May,” “Must,” “Shall,” “Should,” and the imperative
form of verbs.
3.4.1 “May” is used to indicate that a provision of this
method is optional.
3.4.2 “Must,” “Shall,” and the imperative form of verbs
(such as “record” or “enter”) are used to indicate that a provision
of this method is mandatory.
3.4.3 “Should” is used to indicate that a provision of
this method is not mandatory but is highly recommended as good
practice.
3.5 Method 1 refers to 40 CFR part 60, appendix A,
“Method 1 - Sample and velocity traverses for stationary
sources.”
3.6 Method 1 exterior equal-area sector and Method 1
equal-area sector closest to the wall mean any one of the four
equal-area sectors that are closest to the wall for a circular
stack or duct laid out in accordance with section 2.3.1 of Method 1
(see Figure 2H-1).
3.7 Method 1 interior equal-area sector means any of the
equal-area sectors other than the Method 1 exterior equal-area
sectors (as defined in section 3.6) for a circular stack or duct
laid out in accordance with section 2.3.1 of Method 1 (see Figure
2H-1).
3.8 Method 1 traverse point and Method 1 equal-area traverse
point mean a traverse point located at the centroid of an
equal-area sector of a circular stack laid out in accordance with
section 2.3.1 of Method 1.
3.9 Method 2 refers to 40 CFR part 60, appendix A,
“Method 2 - Determination of stack gas velocity and volumetric flow
rate (Type S pitot tube).”
3.10 Method 2F refers to 40 CFR part 60, appendix A,
“Method 2F - Determination of stack gas velocity and volumetric
flow rate with three-dimensional probes.”
3.11 Method 2G refers to 40 CFR part 60, appendix A,
“Method 2G - Determination of stack gas velocity and volumetric
flow rate with two-dimensional probes.”
3.12 1-in. incremented wall effects traverse point means
any of the wall effects traverse points that are located at 1-in.
intervals, i.e., traverse points d1 through dlast (see
Figure 2H-2).
3.13 Partial wall effects traverse means a traverse in
which measurements are taken at fewer than the number of traverse
points required for a “complete wall effects traverse” (as defined
in section 3.1), but are taken at a minimum of two traverse points
in each Method 1 equal-area sector closest to the wall, as
specified in section 8.2.2.
3.14 Relative accuracy test audit (RATA) is a field test
procedure performed in a stack or duct in which a series of
concurrent measurements of the same stack gas stream is taken by a
reference method and an installed monitoring system. A RATA usually
consists of series of 9 to 12 sets of such concurrent measurements,
each of which is referred to as a RATA run. In a volumetric flow
RATA, each reference method run consists of a complete traverse of
the stack or duct.
3.15 Wall effects-unadjusted average velocity means the
average stack gas velocity, not accounting for velocity decay near
the wall, as determined in accordance with Method 2, 2F, or 2G for
a Method 1 traverse consisting of 16 or more points.
3.16 Wall effects-adjusted average velocity means the
average stack gas velocity, taking into account velocity decay near
the wall, as calculated from measurements at 16 or more Method 1
traverse points and at the additional wall effects traverse points
specified in this method.
3.17 Wall effects traverse point means a traverse point
located in accordance with sections 8.2.2 or 8.2.3 of this
method.
4.0 Interferences [Reserved] 5.0 Safety
5.1 This method may involve hazardous materials, operations, and
equipment. This method does not purport to address all of the
health and safety considerations associated with its use. It is the
responsibility of the user of this method to establish appropriate
health and safety practices and to determine the applicability of
occupational health and safety regulatory requirements prior to
performing this method.
6.0 Equipment and Supplies
6.1 The provisions pertaining to equipment and supplies in the
method that is used to take the traverse point measurements (i.e.,
Method 2, 2F, or 2G) are applicable under this method.
7.0 Reagents and Standards [Reserved] 8.0 Sample Collection and
Analysis
8.1 Default Wall Effects Adjustment Factors. A default wall
effects adjustment factor of 0.9900 for brick and mortar stacks and
0.9950 for all other types of stacks and ducts may be used without
conducting the following procedures.
8.2 Traverse Point Locations. Determine the location of the
Method 1 traverse points in accordance with section 8.2.1 and the
location of the traverse points for either a partial wall effects
traverse in accordance with section 8.2.2 or a complete wall
effects traverse in accordance with section 8.2.3.
8.2.1 Method 1 equal-area traverse point locations. Determine
the location of the Method 1 equal-area traverse points for a
traverse consisting of 16 or more points using Table 1-2 (Location
of Traverse Points in Circular Stacks) of Method 1.
8.2.2 Partial wall effects traverse. For a partial wall effects
traverse, measurements must be taken at a minimum of the following
two wall effects traverse point locations in all four Method 1
equal-area sectors closest to the wall: (1) 1 in. (2.5 cm) from the
wall (except as provided in section 8.2.2.1) and (2) drem, as
determined using Equation 2H-1 or 2H-2 (see section 8.2.2.2).
8.2.2.1 If the probe cannot be positioned at 1 in. (2.5 cm) from
the wall (e.g., because of insufficient room to withdraw the probe
shaft) or if velocity pressure cannot be detected at 1 in. (2.5 cm)
from the wall (for any reason other than build-up of particulate
matter in the bottom of a duct), take measurements at the 1-in.
incremented wall effects traverse point closest to the wall where
the probe can be positioned and velocity pressure can be
detected.
8.2.2.2 Calculate the distance of drem from the wall to within ±
1/4 in. (6.4 mm) using Equation 2H-1 or Equation 2H-2 (for a
16-point traverse).
Where:
r = the stack or duct radius determined from direct
measurement of the stack or duct diameter in accordance with
section 8.6 of Method 2F or Method 2G, in. (cm); p = the
number of Method 1 equal-area traverse points on a diameter,
p ≥8 (e.g., for a 16-point traverse, p = 8);
dlast and drem are defined in sections 3.2 and 3.3
respectively, in. (cm). For a 16-point Method 1 traverse, Equation
2H-1 becomes:
8.2.2.3 Measurements may be taken at any number of additional
wall effects traverse points, with the following provisions.
(a) dlast must not be closer to the center of the stack
or duct than the distance of the interior edge (boundary),
db, of the Method 1 equal-area sector closest to the wall
(see Figure 2H-2 or 2H-3). That is,
Where:
Table 2H-1 shows db as a function of the stack or duct radius,
r, for traverses ranging from 16 to 48 points (i.e., for
values of p ranging from 8 to 24).
(b) Each point must be located at a distance that is a whole
number (e.g., 1, 2, 3) multiple of 1 in. (2.5 cm).
(c) Points do not have to be located at consecutive 1-in.
intervals. That is, one or more 1-in. incremented points may be
skipped. For example, it would be acceptable for points to be
located at 1 in. (2.5 cm), 3 in. (7.6 cm), 5 in. (12.7 cm), dlast,
and drem; or at 1 in. (2.5 cm), 2 in. (5.1 cm), 4 in. (10.2 cm), 7
in. (17.8 cm), dlast, and drem. Follow the instructions in section
8.7.1.2 of this method for recording results for wall effects
traverse points that are skipped. It should be noted that the full
extent of velocity decay may not be accounted for if measurements
are not taken at all 1-in. incremented points close to the
wall.
8.2.3 Complete wall effects traverse. For a complete wall
effects traverse, measurements must be taken at the following
points in all four Method 1 equal-area sectors closest to the
wall.
(a) The 1-in. incremented wall effects traverse point closest to
the wall where the probe can be positioned and velocity can be
detected, but no farther than 4 in. (10.2 cm) from the wall.
(b) Every subsequent 1-in. incremented wall effects traverse
point out to the interior edge of the Method 1 equal-area sector or
to 12 in. (30.5 cm) from the wall, whichever comes first. Note: In
stacks or ducts with diameters greater than 15.6 ft (4.8 m) the
interior edge of the Method 1 equal-area sector is farther from the
wall than 12 in. (30.5 cm).
(c) drem, as determined using Equation 2H-1 or 2H-2 (as
applicable). Note: For a complete traverse of a stack or duct with
a diameter less than 16.5 ft (5.0 m), the distance between
drem and dlast is less than or equal to 1/2 in. (12.7
mm). As discussed in section 8.2.4.2, when the distance between
drem and dlast is less than or equal to 1/2 in. (12.7
mm), the velocity measured at dlast may be used for
drem. Thus, it is not necessary to calculate the distance of
drem or to take measurements at drem when conducting
a complete traverse of a stack or duct with a diameter less than
16.5 ft (5.0 m).
8.2.4 Special considerations. The following special
considerations apply when the distance between traverse points is
less than or equal to 1/2 in. (12.7 mm).
8.2.4.1 A wall effects traverse point and the Method 1 traverse
point. If the distance between a wall effects traverse point and
the Method 1 traverse point is less than or equal to 1/2 in. (12.7
mm), taking measurements at both points is allowed but not required
or recommended; if measurements are taken at only one point, take
the measurements at the point that is farther from the wall and use
the velocity obtained at that point as the value for both points
(see sections 8.2.3 and 9.2 for related requirements).
8.2.4.2 drem and dlast. If the distance between
drem and dlast is less than or equal to 1/2 in. (12.7
mm), taking measurements at drem is allowed but not required
or recommended; if measurements are not taken at drem, the
measured velocity value at dlast must be used as the value
for both dlast and drem.
8.3 Traverse Point Sampling Order and Probe Selection. Determine
the sampling order of the Method 1 and wall effects traverse points
and select the appropriate probe for the measurements, taking into
account the following considerations.
8.3.1 Traverse points on any radius may be sampled in either
direction (i.e., from the wall toward the center of the stack or
duct, or vice versa).
8.3.2 To reduce the likelihood of velocity variations during the
time of the traverse and the attendant potential impact on the wall
effects-adjusted and unadjusted average velocities, the following
provisions of this method shall be met.
8.3.2.1 Each complete set of Method 1 and wall effects traverse
points accessed from the same port shall be sampled without
interruption. Unless traverses are performed simultaneously in all
ports using separate probes at each port, this provision disallows
first sampling all Method 1 points at all ports and then sampling
all the wall effects points.
8.3.2.2 The entire integrated Method 1 and wall effects traverse
across all test ports shall be as short as practicable, consistent
with the measurement system response time (see section 8.4.1.1) and
sampling (see section 8.4.1.2) provisions of this method.
8.3.3 It is recommended but not required that in each Method 1
equal-area sector closest to the wall, the Method 1 equal-area
traverse point should be sampled in sequence between the adjacent
wall effects traverse points. For example, for the traverse point
configuration shown in Figure 2H-2, it is recommended that the
Method 1 equal-area traverse point be sampled between dlast
and drem. In this example, if the traverse is conducted from
the wall toward the center of the stack or duct, it is recommended
that measurements be taken at points in the following order:
d1, d2, dlast, the Method 1 traverse point,
drem, and then at the traverse points in the three Method 1
interior equal-area sectors.
8.3.4 The same type of probe must be used to take measurements
at all Method 1 and wall effects traverse points. However,
different copies of the same type of probe may be used at different
ports (e.g., Type S probe 1 at port A, Type S probe 2 at port B) or
at different traverse points accessed from a particular port (e.g.,
Type S probe 1 for Method 1 interior traverse points accessed from
port A, Type S probe 2 for wall effects traverse points and the
Method 1 exterior traverse point accessed from port A). The
identification number of the probe used to obtain measurements at
each traverse point must be recorded.
8.4 Measurements at Method 1 and Wall Effects Traverse Points.
Conduct measurements at Method 1 and wall effects traverse points
in accordance with Method 2, 2F, or 2G and in accordance with the
provisions of the following subsections (some of which are included
in Methods 2F and 2G but not in Method 2), which are particularly
important for wall effects testing.
8.4.1 Probe residence time at wall effects traverse points. Due
to the steep temperature and pressure gradients that can occur
close to the wall, it is very important for the probe residence
time (i.e., the total time spent at a traverse point) to be long
enough to ensure collection of representative temperature and
pressure measurements. The provisions of Methods 2F and 2G in the
following subsections shall be observed.
8.4.1.1 System response time. Determine the response time of
each probe measurement system by inserting and positioning the
“cold” probe (at ambient temperature and pressure) at any Method 1
traverse point. Read and record the probe differential pressure,
temperature, and elapsed time at 15-second intervals until stable
readings for both pressure and temperature are achieved. The
response time is the longer of these two elapsed times. Record the
response time.
8.4.1.2 Sampling. At the start of testing in each port (i.e.,
after a probe has been inserted into the stack gas stream), allow
at least the response time to elapse before beginning to take
measurements at the first traverse point accessed from that port.
Provided that the probe is not removed from the stack gas stream,
measurements may be taken at subsequent traverse points accessed
from the same test port without waiting again for the response time
to elapse.
8.4.2 Temperature measurement for wall effects traverse points.
Either (1) take temperature measurements at each wall effects
traverse point in accordance with the applicable provisions of
Method 2, 2F, or 2G; or (2) use the temperature measurement at the
Method 1 traverse point closest to the wall as the temperature
measurement for all the wall effects traverse points in the
corresponding equal-area sector.
8.4.3 Non-detectable velocity pressure at wall effects traverse
points. If the probe cannot be positioned at a wall effects
traverse point or if no velocity pressure can be detected at a wall
effects point, measurements shall be taken at the first subsequent
wall effects traverse point farther from the wall where velocity
can be detected. Follow the instructions in section 8.7.1.2 of this
method for recording results for wall effects traverse points where
velocity pressure cannot be detected. It should be noted that the
full extent of velocity decay may not be accounted for if
measurements are not taken at the 1-in. incremented wall effects
traverse points closest to the wall.
8.5 Data Recording. For each wall effects and Method 1 traverse
point where measurements are taken, record all pressure,
temperature, and attendant measurements prescribed in section 3 of
Method 2 or section 8.0 of Method 2F or 2G, as applicable.
8.6 Point Velocity Calculation. For each wall effects and Method
1 traverse point, calculate the point velocity value (vi) in
accordance with sections 12.1 and 12.2 of Method 2F for tests using
Method 2F and in accordance with sections 12.1 and 12.2 of Method
2G for tests using Method 2 and Method 2G. (Note that the term (vi)
in this method corresponds to the term (va(i)) in Methods 2F and
2G.) When the equations in the indicated sections of Method 2G are
used in deriving point velocity values for Method 2 tests, set the
value of the yaw angles appearing in the equations to 0°.
8.7 Tabulating Calculated Point Velocity Values for Wall Effects
Traverse Points. Enter the following values in a hardcopy or
electronic form similar to Form 2H-1 (for 16-point Method 1
traverses) or Form 2H-2 (for Method 1 traverses consisting of more
than 16 points). A separate form must be completed for each of the
four Method 1 equal-area sectors that are closest to the wall.
(a) Port ID (e.g., A, B, C, or D)
(b) Probe type
(c) Probe ID
(d) Stack or duct diameter in ft (m) (determined in accordance
with section 8.6 of Method 2F or Method 2G)
(e) Stack or duct radius in in. (cm)
(f) Distance from the wall of wall effects traverse points at
1-in. intervals, in ascending order starting with 1 in. (2.5 cm)
(column A of Form 2H-1 or 2H-2)
(g) Point velocity values (vd) for 1-in. incremented traverse
points (see section 8.7.1), including dlast (see section 8.7.2)
(h) Point velocity value (vdrem) at drem (see section
8.7.3).
8.7.1 Point velocity values at wall effects traverse points
other than dlast. For every 1-in. incremented wall effects traverse
point other than dlast, enter in column B of Form 2H-1 or 2H-2
either the velocity measured at the point (see section 8.7.1.1) or
the velocity measured at the first subsequent traverse point
farther from the wall (see section 8.7.1.2). A velocity value must
be entered in column B of Form 2H-1 or 2H-2 for every 1-in.
incremented traverse point from d1 (representing the wall effects
traverse point 1 in. [2.5 cm] from the wall) to dlast.
8.7.1.1 For wall effects traverse points where the probe can be
positioned and velocity pressure can be detected, enter the value
obtained in accordance with section 8.6.
8.7.1.2 For wall effects traverse points that were skipped [see
section 8.2.2.3(c)] and for points where the probe cannot be
positioned or where no velocity pressure can be detected, enter the
value obtained at the first subsequent traverse point farther from
the wall where velocity pressure was detected and measured and
follow the entered value with a “flag,” such as the notation “NM,”
to indicate that “no measurements” were actually taken at this
point.
8.7.2 Point velocity value at dlast. For dlast,
enter in column B of Form 2H-1 or 2H-2 the measured value obtained
in accordance with section 8.6.
8.7.3 Point velocity value (vdrem) at drem. Enter
the point velocity value obtained at drem in column G of row
4a in Form 2H-1 or 2H-2. If the distance between drem and
dlast is less than or equal to 1/2 in. (12.7 mm), the
measured velocity value at dlast may be used as the value at
drem (see section 8.2.4.2).
9.0 Quality Control.
9.1 Particulate Matter Build-up in Horizontal Ducts. Wall
effects testing of horizontal circular ducts should be conducted
only if build-up of particulate matter or other material in the
bottom of the duct is not present.
9.2 Verifying Traverse Point Distances. In taking measurements
at wall effects traverse points, it is very important for the probe
impact pressure port to be positioned as close as practicable to
the traverse point locations in the gas stream. For this reason,
before beginning wall effects testing, it is important to calculate
and record the traverse point positions that will be marked on each
probe for each port, taking into account the distance that each
port nipple (or probe mounting flange for automated probes) extends
out of the stack and any extension of the port nipple (or mounting
flange) into the gas stream. To ensure that traverse point
positions are properly identified, the following procedures should
be performed on each probe used.
9.2.1 Manual probes. Mark the probe insertion distance of the
wall effects and Method 1 traverse points on the probe sheath so
that when a mark is aligned with the outside face of the stack
port, the probe impact port is located at the calculated distance
of the traverse point from the stack inside wall. The use of
different colored marks is recommended for designating the wall
effects and Method 1 traverse points. Before the first use of each
probe, check to ensure that the distance of each mark from the
center of the probe impact pressure port agrees with the previously
calculated traverse point positions to within ± 1/4 in. (6.4
mm).
9.2.2 Automated probe systems. For automated probe systems that
mechanically position the probe head at prescribed traverse point
positions, activate the system with the probe assemblies removed
from the test ports and sequentially extend the probes to the
programmed location of each wall effects traverse point and the
Method 1 traverse points. Measure the distance between the center
of the probe impact pressure port and the inside of the probe
assembly mounting flange for each traverse point. The measured
distances must agree with the previously calculated traverse point
positions to within ± 1/4 in. (6.4 mm).
9.3 Probe Installation. Properly sealing the port area is
particularly important in taking measurements at wall effects
traverse points. For testing involving manual probes, the area
between the probe sheath and the port should be sealed with a
tightly fitting flexible seal made of an appropriate material such
as heavy cloth so that leakage is minimized. For automated probe
systems, the probe assembly mounting flange area should be checked
to verify that there is no leakage.
9.4 Velocity Stability. This method should be performed only
when the average gas velocity in the stack or duct is relatively
constant over the duration of the test. If the average gas velocity
changes significantly during the course of a wall effects test, the
test results should be discarded.
10.0 Calibration
10.1 The calibration coefficient(s) or curves obtained under
Method 2, 2F, or 2G and used to perform the Method 1 traverse are
applicable under this method.
11.0 Analytical Procedure
11.1 Sample collection and analysis are concurrent for this
method (see section 8).
12.0 Data Analysis and Calculations
12.1 The following calculations shall be performed to obtain a
wall effects adjustment factor (WAF) from (1) the wall
effects-unadjusted average velocity (T4avg), (2) the
replacement velocity (v ej) for each of the four Method 1
sectors closest to the wall, and (3) the average stack gas velocity
that accounts for velocity decay near the wall (v avg).
12.2 Nomenclature. The following terms are listed in the order
in which they appear in Equations 2H-5 through 2H-21.
vavg = the average stack gas velocity, unadjusted for wall
effects, actual ft/sec (m/sec); vii = stack gas point
velocity value at Method 1 interior equal-area sectors, actual
ft/sec (m/sec); vej = stack gas point velocity value,
unadjusted for wall effects, at Method 1 exterior equal-area
sectors, actual ft/sec (m/sec); i = index of Method 1
interior equal-area traverse points; j = index of Method 1
exterior equal-area traverse points; n = total number of
traverse points in the Method 1 traverse; vdecd = the wall
effects decay velocity for a sub-sector located between the
traverse points at distances d−1 (in metric units,
d−2.5) and d from the wall, actual ft/sec (m/sec);
vd = the measured stack gas velocity at distance d
from the wall, actual ft/sec (m/sec); Note: v0 = 0; d
= the distance of a 1-in. incremented wall effects traverse point
from the wall, for traverse points d1 through dlast,
in. (cm); Ad = the cross-sectional area of a sub-sector
located between the traverse points at distances d−1 (in
metric units, d−2.5) and d from the wall, in. 2 (cm
2) ( e.g., sub-sector A2 shown in Figures 2H-3 and 2H-4); r
= the stack or duct radius, in. (cm); Qd = the stack gas
volumetric flow rate for a sub-sector located between the traverse
points at distances d−1 (in metric units, d−2.5) and
d from the wall, actual ft-in. 2/sec (m-cm 2/sec);
Qd1→dlast = the total stack gas volumetric flow rate for all
sub-sectors located between the wall and dlast, actual
ft-in. 2/sec (m-cm 2/sec); dlast = the distance from the
wall of the last 1-in. incremented wall effects traverse point, in.
(cm); Adrem = the cross-sectional area of the sub-sector
located between dlast and the interior edge of the Method 1
equal-area sector closest to the wall, in. 2 (cm 2) (see Figure
2H-4); p = the number of Method 1 traverse points per
diameter, p≥8 (e.g., for a 16-point traverse, p = 8);
drem = the distance from the wall of the centroid of the
area between dlast and the interior edge of the Method 1
equal-area sector closest to the wall, in. (cm); Qdrem = the
total stack gas volumetric flow rate for the sub-sector located
between dlast and the interior edge of the Method 1
equal-area sector closest to the wall, actual ft-in. 2/sec (m-cm
2/sec); vdrem = the measured stack gas velocity at distance
drem from the wall, actual ft/sec (m/sec); QT = the
total stack gas volumetric flow rate for the Method 1 equal-area
sector closest to the wall, actual ft-in. 2/sec (m-cm 2/sec);
v ej = the replacement stack gas velocity for the Method 1
equal-area sector closest to the wall, i.e., the stack gas point
velocity value, adjusted for wall effects, for the j th Method 1
equal-area sector closest to the wall, actual ft/sec (m/sec);
v avg = the average stack gas velocity that accounts for
velocity decay near the wall, actual ft/sec (m/sec); WAF =
the wall effects adjustment factor derived from vavg and
v avg for a single traverse, dimensionless; v final =
the final wall effects-adjusted average stack gas velocity that
replaces the unadjusted average stack gas velocity obtained using
Method 2, 2F, or 2G for a field test consisting of a single
traverse, actual ft/sec (m/sec); W A F = the wall effects
adjustment factor that is applied to the average velocity,
unadjusted for wall effects, in order to obtain the final wall
effects-adjusted stack gas velocity, v final or, v
final(k), dimensionless; v final(k) = the final wall
effects-adjusted average stack gas velocity that replaces the
unadjusted average stack gas velocity obtained using Method 2, 2F,
or 2G on run k of a RATA or other multiple-run field test
procedure, actual ft/sec (m/sec); vavg(k) = the average
stack gas velocity, obtained on run k of a RATA or other
multiple-run procedure, unadjusted for velocity decay near the
wall, actual ft/sec (m/sec); k=index of runs in a RATA or
other multiple-run procedure.
12.3 Calculate the average stack gas velocity that does not
account for velocity decay near the wall (vavg) using
Equation 2H-5.
(Note
that vavg in Equation 2H-5 is the same as v(a)avg in
Equations 2F-9 and 2G-8 in Methods 2F and 2G, respectively.)
For a 16-point traverse, Equation 2H-5 may be written as
follows:
12.4 Calculate the replacement velocity, v ej, for each
of the four Method 1 equal-area sectors closest to the wall using
the procedures described in sections 12.4.1 through 12.4.8. Forms
2H-1 and 2H-2 provide sample tables that may be used in either
hardcopy or spreadsheet format to perform the calculations
described in sections 12.4.1 through 12.4.8. Forms 2H-3 and 2H-4
provide examples of Form 2H-1 filled in for partial and complete
wall effects traverses.
12.4.1 Calculate the average velocity (designated the “decay
velocity,” vdecd) for each sub-sector located between the wall and
dlast (see Figure 2H-3) using Equation 2H-7.
For each
line in column A of Form 2H-1 or 2H-2 that contains a value of d,
enter the corresponding calculated value of vdecd in column C.
12.4.2 Calculate the cross-sectional area between the wall and
the first 1-in. incremented wall effects traverse point and between
successive 1-in. incremented wall effects traverse points, from the
wall to dlast (see Figure 2H-3), using Equation 2H-8.
For each
line in column A of Form 2H-1 or 2H-2 that contains a value of d,
enter the value of the expression 1/4 π(r−d + 1) 2 in column
D, the value of the expression 1/4 π(r−d) 2 in column E, and
the value of Ad in column F. Note that Equation 2H-8 is
designed for use only with English units (in.). If metric units
(cm) are used, the first term, 1/4 π(r−d + 1) 2, must be
changed to 1/4 π(r−d + 2.5) 2. This change must also be made
in column D of Form 2H-1 or 2H-2.
12.4.3 Calculate the volumetric flow through each
cross-sectional area derived in section 12.4.2 by multiplying the
values of vdecd, derived according to section 12.4.1, by the
cross-sectional areas derived in section 12.4.2 using Equation
2H-9.
For each
line in column A of Form 2H-1 or 2H-2 that contains a value of
d, enter the corresponding calculated value of Qd in
column G.
12.4.4 Calculate the total volumetric flow through all
sub-sectors located between the wall and dlast, using
Equation 2H-10.
Enter the
calculated value of Qd1→cdlast in line 3 of column G of Form
2H-1 or 2H-2.
12.4.5 Calculate the cross-sectional area of the sub-sector
located between dlast and the interior edge of the Method 1
equal-area sector (e.g., sub-sector Adrem shown in Figures
2H-3 and 2H-4) using Equation 2H-11.
For a
16-point traverse (eight points per diameter), Equation 2H-11 may
be written as follows: Enter the
calculated value of Adrem in line 4b of column G of Form
2H-1 or 2H-2.
12.4.6 Calculate the volumetric flow for the sub-sector located
between dlast and the interior edge of the Method 1
equal-area sector, using Equation 2H-13.
In
Equation 2H-13, vdrem is either (1) the measured velocity
value at drem or (2) the measured velocity at dlast,
if the distance between drem and dlast is less than
or equal to 1/2 in. (12.7 mm) and no velocity measurement is taken
at drem (see section 8.2.4.2). Enter the calculated value of
Qdrem in line 4c of column G of Form 2H-1 or 2H-2.
12.4.7 Calculate the total volumetric flow for the Method 1
equal-area sector closest to the wall, using Equation 2H-14.
Enter the
calculated value of QT in line 5a of column G of Form 2H-1
or 2H-2.
12.4.8 Calculate the wall effects-adjusted replacement velocity
value for the Method 1 equal-area sector closest to the wall, using
Equation 2H-15.
For a
16-point traverse (eight points per diameter), Equation 2H-15 may
be written as follows: Enter the
calculated value of v ej in line 5B of column G of Form 2H-1
or 2H-2.
12.5 Calculate the wall effects-adjusted average velocity,
v avg, by replacing the four values of vej shown in
Equation 2H-5 with the four wall effects-adjusted replacement
velocity values,v ej, calculated according to section
12.4.8, using Equation 2H-17.
For a
16-point traverse, Equation 2H-17 may be written as follows:
12.6 Calculate the wall effects adjustment factor, WAF, using
Equation 2H-19.
12.6.1 Partial wall effects traverse. If a partial wall effects
traverse (see section 8.2.2) is conducted, the value obtained from
Equation 2H-19 is acceptable and may be reported as the wall
effects adjustment factor provided that the value is greater than
or equal to 0.9800. If the value is less than 0.9800, it shall not
be used and a wall effects adjustment factor of 0.9800 may be used
instead.
12.6.2 Complete wall effects traverse. If a complete wall
effects traverse (see section 8.2.3) is conducted, the value
obtained from Equation 2H-19 is acceptable and may be reported as
the wall effects adjustment factor provided that the value is
greater than or equal to 0.9700. If the value is less than 0.9700,
it shall not be used and a wall effects adjustment factor of 0.9700
may be used instead. If the wall effects adjustment factor for a
particular stack or duct is less than 0.9700, the tester may (1)
repeat the wall effects test, taking measurements at more Method 1
traverse points and (2) recalculate the wall effects adjustment
factor from these measurements, in an attempt to obtain a wall
effects adjustment factor that meets the 0.9700 specification and
completely characterizes the wall effects.
12.7 Applying a Wall Effects Adjustment Factor. A default wall
effects adjustment factor, as specified in section 8.1, or a
calculated wall effects adjustment factor meeting the requirements
of section 12.6.1 or 12.6.2 may be used to adjust the average stack
gas velocity obtained using Methods 2, 2F, or 2G to take into
account velocity decay near the wall of circular stacks or ducts.
Default wall effects adjustment factors specified in section 8.1
and calculated wall effects adjustment factors that meet the
requirements of section 12.6.1 and 12.6.2 are summarized in Table
2H-2.
12.7.1 Single-run tests. Calculate the final wall
effects-adjusted average stack gas velocity for field tests
consisting of a single traverse using Equation 2H-20.
The wall
effects adjustment factor, WAF, shown in Equation 2H-20, may be (1)
a default wall effects adjustment factor, as specified in section
8.1, or (2) a calculated adjustment factor that meets the
specifications in sections 12.6.1 or 12.6.2. If a calculated
adjustment factor is used in Equation 2H-20, the factor must have
been obtained during the same traverse in which vavg was
obtained.
12.7.2 RATA or other multiple run test procedure. Calculate the
final wall effects-adjusted average stack gas velocity for any run
k of a RATA or other multiple-run procedure using Equation
2H-21.
The wall
effects adjustment factor, W A F , shown in Equation 2H-21 may be
(1) a default wall effects adjustment factor, as specified in
section 8.1; (2) a calculated adjustment factor (meeting the
specifications in sections 12.6.1 or 12.6.2) obtained from any
single run of the RATA that includes run k; or (3) the
arithmetic average of more than one WAF (each meeting the
specifications in sections 12.6.1 or 12.6.2) obtained through wall
effects testing conducted during several runs of the RATA that
includes run k. If wall effects adjustment factors (meeting
the specifications in sections 12.6.1 or 12.6.2) are determined for
more than one RATA run, the arithmetic average of all of the
resulting calculated wall effects adjustment factors must be used
as the value of W A F and applied to all runs of that RATA.
If a calculated, not a default, wall effects adjustment factor is
used in Equation 2H-21, the average velocity unadjusted for wall
effects, vavg(k) must be obtained from runs in which the
number of Method 1 traverse points sampled does not exceed the
number of Method 1 traverse points in the runs used to derive the
wall effects adjustment factor, W A F , shown in Equation 2H-21.
12.8 Calculating Volumetric Flow Using Final Wall
Effects-Adjusted Average Velocity Value. To obtain a stack gas flow
rate that accounts for velocity decay near the wall of circular
stacks or ducts, replace vs in Equation 2-10 in Method 2, or
va(avg) in Equations 2F-10 and 2F-11 in Method 2F, or
va(avg) in Equations 2G-9 and 2G-10 in Method 2G with one of
the following.
12.8.1 For single-run test procedures, use the final wall
effects-adjusted average stack gas velocity, v final,
calculated according to Equation 2H-20.
12.8.2 For RATA and other multiple run test procedures, use the
final wall effects-adjusted average stack gas velocity, v
final(k), calculated according to Equation 2H-21.
16.1 Field Test Reports. Field test reports shall be submitted
to the Agency according to the applicable regulatory requirements.
When Method 2H is performed in conjunction with Method 2, 2F, or 2G
to derive a wall effects adjustment factor, a single consolidated
Method 2H/2F (or 2H/2G) field test report should be prepared. At a
minimum, the consolidated field test report should contain (1) all
of the general information, and data for Method 1 points, specified
in section 16.0 of Method 2F (when Method 2H is used in conjunction
with Method 2F) or section 16.0 of Method 2G (when Method 2H is
used in conjunction with Method 2 or 2G) and (2) the additional
general information, and data for Method 1 points and wall effects
points, specified in this section (some of which are included in
section 16.0 of Methods 2F and 2G and are repeated in this section
to ensure complete reporting for wall effects testing).
16.1.1 Description of the source and site. The field test report
should include the descriptive information specified in section
16.1.1 of Method 2F (when using Method 2F) or 2G (when using either
Method 2 or 2G). It should also include a description of the stack
or duct's construction material along with the diagram showing the
dimensions of the stack or duct at the test port elevation
prescribed in Methods 2F and 2G. The diagram should indicate the
location of all wall effects traverse points where measurements
were taken as well as the Method 1 traverse points. The diagram
should provide a unique identification number for each wall effects
and Method 1 traverse point, its distance from the wall, and its
location relative to the probe entry ports.
16.1.2 Field test forms. The field test report should include a
copy of Form 2H-1, 2H-2, or an equivalent for each Method 1
exterior equal-area sector.
16.1.3 Field test data. The field test report should include the
following data for the Method 1 and wall effects traverse.
16.1.3.1 Data for each traverse point. The field test report
should include the values specified in section 16.1.3.2 of Method
2F (when using Method 2F) or 2G (when using either Method 2 or 2G)
for each Method 1 and wall effects traverse point. The provisions
of section 8.4.2 of Method 2H apply to the temperature measurements
reported for wall effects traverse points. For each wall effects
and Method 1 traverse point, the following values should also be
included in the field test report.
(a) Traverse point identification number for each Method 1 and
wall effects traverse point.
(b) Probe type.
(c) Probe identification number.
(d) Probe velocity calibration coefficient (i.e., Cp when Method
2 or 2G is used; F2 when Method 2F is used).
For each Method 1 traverse point in an exterior equal-area
sector, the following additional value should be included.
(e) Calculated replacement velocity, v ej, accounting for
wall effects.
16.1.3.2 Data for each run. The values specified in section
16.1.3.3 of Method 2F (when using Method 2F) or 2G (when using
either Method 2 or 2G) should be included in the field test report
once for each run. The provisions of section 12.8 of Method 2H
apply for calculating the reported gas volumetric flow rate. In
addition, the following Method 2H run values should also be
included in the field test report.
(a) Average velocity for run, accounting for wall effects,
v avg.
(b) Wall effects adjustment factor derived from a test run,
WAF.
16.1.3.3 Data for a complete set of runs. The values specified
in section 16.1.3.4 of Method 2F (when using Method 2F) or 2G (when
using either Method 2 or 2G) should be included in the field test
report once for each complete set of runs. In addition, the field
test report should include the wall effects adjustment factor,
W A F , that is applied in accordance with section 12.7.1 or
12.7.2 to obtain the final wall effects-adjusted average stack gas
velocity v final or v final(k).
16.1.4 Quality assurance and control. Quality assurance and
control procedures, specifically tailored to wall effects testing,
should be described.
16.2 Reporting a Default Wall Effects Adjustment Factor. When a
default wall effects adjustment factor is used in accordance with
section 8.1 of this method, its value and a description of the
stack or duct's construction material should be reported in lieu of
submitting a test report.
17.0 References.
(1) 40 CFR Part 60, Appendix A, Method 1 - Sample and velocity
traverses for stationary sources.
(2) 40 CFR Part 60, Appendix A, Method 2 - Determination of
stack gas velocity and volumetric flow rate (Type S pitot
tube).
(3) 40 CFR Part 60, Appendix A, Method 2F - Determination of
stack gas velocity and volumetric flow rate with three-dimensional
probes.
(4) 40 CFR Part 60, Appendix A, Method 2G - Determination of
stack gas velocity and volumetric flow rate with two-dimensional
probes.
(5) 40 CFR Part 60, Appendix A, Method 3 - Gas analysis for
carbon dioxide, oxygen, excess air, and dry molecular weight.
(6) 40 CFR Part 60, Appendix A, Method 3A - Determination of
oxygen and carbon dioxide concentrations in emissions from
stationary sources (instrumental analyzer procedure).
(7) 40 CFR Part 60, Appendix A, Method 4 - Determination of
moisture content in stack gases.
(8) Emission Measurement Center (EMC) Approved Alternative
Method (ALT-011) “Alternative Method 2 Thermocouple Calibration
Procedure.”
(9) The Cadmus Group, Inc., 1998, “EPA Flow Reference Method
Testing and Analysis: Data Report, Texas Utilities, DeCordova Steam
Electric Station, Volume I: Test Description and Appendix A (Data
Distribution Package),” EPA/430-R-98-015a.
(10) The Cadmus Group, Inc., 1998, “EPA Flow Reference Method
Testing and Analysis: Data Report, Texas Utilities, Lake Hubbard
Steam Electric Station, Volume I: Test Description and Appendix A
(Data Distribution Package),” EPA/430-R-98-017a.
(11) The Cadmus Group, Inc., 1998, “EPA Flow Reference Method
Testing and Analysis: Data Report, Pennsylvania Electric Co.,
G.P.U. Genco Homer City Station: Unit 1, Volume I: Test Description
and Appendix A (Data Distribution Package),” EPA/430-R-98-018a.
(12) The Cadmus Group, Inc., May 1999, “EPA Flow Reference
Method Testing and Analysis: Findings Report,”
EPA/430-R-99-009.
(13) The Cadmus Group, Inc., 1997, “EPA Flow Reference Method
Testing and Analysis: Wind Tunnel Experimental Results,”
EPA/430-R-97-013.
(14) National Institute of Standards and Technology, 1998,
“Report of Special Test of Air Speed Instrumentation, Four Prandtl
Probes, Four S-Type Probes, Four French Probes, Four Modified Kiel
Probes,” Prepared for the U.S. Environmental Protection Agency
under IAG No. DW13938432-01-0.
(15) National Institute of Standards and Technology, 1998,
“Report of Special Test of Air Speed Instrumentation, Five
Autoprobes,” Prepared for the U.S. Environmental Protection Agency
under IAG No. DW13938432-01-0.
(16) National Institute of Standards and Technology, 1998,
“Report of Special Test of Air Speed Instrumentation, Eight
Spherical Probes,” Prepared for the U.S. Environmental Protection
Agency under IAG No. DW13938432-01-0.
(17) National Institute of Standards and Technology, 1998,
“Report of Special Test of Air Speed Instrumentation, Four DAT
Probes,” Prepared for the U.S. Environmental Protection Agency
under IAG No. DW13938432-01-0.
(18) Massachusetts Institute of Technology (MIT), 1998,
“Calibration of Eight Wind Speed Probes Over a Reynolds Number
Range of 46,000 to 725,000 per Foot, Text and Summary Plots,” Plus
Appendices, WBWT-TR-1317, Prepared for The Cadmus Group, Inc.,
under EPA Contract 68-W6-0050, Work Assignment 0007AA-3.
(19) Fossil Energy Research Corporation, Final Report, “Velocity
Probe Tests in Non-axial Flow Fields,” November 1998, Prepared for
the U.S. Environmental Protection Agency.
(20) Fossil Energy Research Corporation, “Additional Swirl
Tunnel Tests: E-DAT and T-DAT Probes,” February 24, 1999, Technical
Memorandum Prepared for U.S. Environmental Protection Agency, P.O.
No. 7W-1193-NALX.
Method 3 - Gas
Analysis for the Determination of Dry Molecular Weight Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling) essential to its performance. Some material is
incorporated by reference from other methods in this part.
Therefore, to obtain reliable results, persons using this method
should also have a thorough knowledge of Method 1.
1.0 Scope and Application
1.1 Analytes.
Analytes
CAS No.
Sensitivity
Oxygen (O2)
7782-44-7
2,000 ppmv.
Nitrogen (N2)
7727-37-9
N/A.
Carbon dioxide
(CO2)
124-38-9
2,000 ppmv.
Carbon monoxide
(CO)
630-08-0
N/A.
1.2 Applicability. This method is applicable for the
determination of CO2 and O2 concentrations and dry molecular weight
of a sample from an effluent gas stream of a fossil-fuel combustion
process or other process.
1.3 Other methods, as well as modifications to the procedure
described herein, are also applicable for all of the above
determinations. Examples of specific methods and modifications
include: (1) A multi-point grab sampling method using an Orsat
analyzer to analyze the individual grab sample obtained at each
point; (2) a method for measuring either CO2 or O2 and using
stoichiometric calculations to determine dry molecular weight; and
(3) assigning a value of 30.0 for dry molecular weight, in lieu of
actual measurements, for processes burning natural gas, coal, or
oil. These methods and modifications may be used, but are subject
to the approval of the Administrator. The method may also be
applicable to other processes where it has been determined that
compounds other than CO2, O2, carbon monoxide (CO), and nitrogen
(N2) are not present in concentrations sufficient to affect the
results.
1.4 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A gas sample is extracted from a stack by one of the
following methods: (1) single-point, grab sampling; (2)
single-point, integrated sampling; or (3) multi-point, integrated
sampling. The gas sample is analyzed for percent CO2 and percent
O2. For dry molecular weight determination, either an Orsat or a
Fyrite analyzer may be used for the analysis.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Several compounds can interfere, to varying degrees, with
the results of Orsat or Fyrite analyses. Compounds that interfere
with CO2 concentration measurement include acid gases (e.g.,
sulfur dioxide, hydrogen chloride); compounds that interfere with
O2 concentration measurement include unsaturated hydrocarbons
(e.g., acetone, acetylene), nitrous oxide, and ammonia.
Ammonia reacts chemically with the O2 absorbing solution, and when
present in the effluent gas stream must be removed before
analysis.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Corrosive Reagents.
5.2.1 A typical Orsat analyzer requires four reagents: a
gas-confining solution, CO2 absorbent, O2 absorbent, and CO
absorbent. These reagents may contain potassium hydroxide, sodium
hydroxide, cuprous chloride, cuprous sulfate, alkaline pyrogallic
acid, and/or chromous chloride. Follow manufacturer's operating
instructions and observe all warning labels for reagent use.
5.2.2 A typical Fyrite analyzer contains zinc chloride,
hydrochloric acid, and either potassium hydroxide or chromous
chloride. Follow manufacturer's operating instructions and observe
all warning labels for reagent use.
6.0 Equipment and Supplies Note:
As an alternative to the sampling apparatus and systems
described herein, other sampling systems (e.g., liquid
displacement) may be used, provided such systems are capable of
obtaining a representative sample and maintaining a constant
sampling rate, and are, otherwise, capable of yielding acceptable
results. Use of such systems is subject to the approval of the
Administrator.
6.1 Grab Sampling (See Figure 3-1).
6.1.1 Probe. Stainless steel or borosilicate glass tubing
equipped with an in-stack or out-of-stack filter to remove
particulate matter (a plug of glass wool is satisfactory for this
purpose). Any other materials, resistant to temperature at sampling
conditions and inert to all components of the gas stream, may be
used for the probe. Examples of such materials may include
aluminum, copper, quartz glass, and Teflon.
6.1.2 Pump. A one-way squeeze bulb, or equivalent, to transport
the gas sample to the analyzer.
6.2 Integrated Sampling (Figure 3-2).
6.2.1 Probe. Same as in section 6.1.1.
6.2.2 Condenser. An air-cooled or water-cooled condenser, or
other condenser no greater than 250 ml that will not remove O2,
CO2, CO, and N2, to remove excess moisture which would interfere
with the operation of the pump and flowmeter.
6.2.3 Valve. A needle valve, to adjust sample gas flow rate.
6.2.4 Pump. A leak-free, diaphragm-type pump, or equivalent, to
transport sample gas to the flexible bag. Install a small surge
tank between the pump and rate meter to eliminate the pulsation
effect of the diaphragm pump on the rate meter.
6.2.5 Rate Meter. A rotameter, or equivalent, capable of
measuring flow rate to ±2 percent of the selected flow rate. A flow
rate range of 500 to 1000 ml/min is suggested.
6.2.6 Flexible Bag. Any leak-free plastic (e.g., Tedlar,
Mylar, Teflon) or plastic-coated aluminum (e.g., aluminized
Mylar) bag, or equivalent, having a capacity consistent with the
selected flow rate and duration of the test run. A capacity in the
range of 55 to 90 liters (1.9 to 3.2 ft 3) is suggested. To
leak-check the bag, connect it to a water manometer, and pressurize
the bag to 5 to 10 cm H2O (2 to 4 in. H2O). Allow to stand for 10
minutes. Any displacement in the water manometer indicates a leak.
An alternative leak-check method is to pressurize the bag to 5 to
10 cm (2 to 4 in.) H2O and allow to stand overnight. A deflated bag
indicates a leak.
6.2.7 Pressure Gauge. A water-filled U-tube manometer, or
equivalent, of about 30 cm (12 in.), for the flexible bag
leak-check.
6.2.8 Vacuum Gauge. A mercury manometer, or equivalent, of at
least 760 mm (30 in.) Hg, for the sampling train leak-check.
6.3 Analysis. An Orsat or Fyrite type combustion gas
analyzer.
7.0 Reagents and Standards
7.1 Reagents. As specified by the Orsat or Fyrite-type
combustion analyzer manufacturer.
7.2 Standards. Two standard gas mixtures, traceable to National
Institute of Standards and Technology (NIST) standards, to be used
in auditing the accuracy of the analyzer and the analyzer operator
technique:
7.2.1. Gas cylinder containing 2 to 4 percent O2 and 14 to 18
percent CO2.
7.2.2. Gas cylinder containing 2 to 4 percent CO2 and about 15
percent O2.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Single Point, Grab Sampling Procedure.
8.1.1 The sampling point in the duct shall either be at the
centroid of the cross section or at a point no closer to the walls
than 1.0 m (3.3 ft), unless otherwise specified by the
Administrator.
8.1.2 Set up the equipment as shown in Figure 3-1, making sure
all connections ahead of the analyzer are tight. If an Orsat
analyzer is used, it is recommended that the analyzer be
leak-checked by following the procedure in section 11.5; however,
the leak-check is optional.
8.1.3 Place the probe in the stack, with the tip of the probe
positioned at the sampling point. Purge the sampling line long
enough to allow at least five exchanges. Draw a sample into the
analyzer, and immediately analyze it for percent CO2 and percent O2
according to section 11.2.
8.2 Single-Point, Integrated Sampling Procedure.
8.2.1 The sampling point in the duct shall be located as
specified in section 8.1.1.
8.2.2 Leak-check (optional) the flexible bag as in section
6.2.6. Set up the equipment as shown in Figure 3-2. Just before
sampling, leak-check (optional) the train by placing a vacuum gauge
at the condenser inlet, pulling a vacuum of at least 250 mm Hg (10
in. Hg), plugging the outlet at the quick disconnect, and then
turning off the pump. The vacuum should remain stable for at least
0.5 minute. Evacuate the flexible bag. Connect the probe, and place
it in the stack, with the tip of the probe positioned at the
sampling point. Purge the sampling line. Next, connect the bag, and
make sure that all connections are tight.
8.2.3 Sample Collection. Sample at a constant rate (±10
percent). The sampling run should be simultaneous with, and for the
same total length of time as, the pollutant emission rate
determination. Collection of at least 28 liters (1.0 ft 3) of
sample gas is recommended; however, smaller volumes may be
collected, if desired.
8.2.4 Obtain one integrated flue gas sample during each
pollutant emission rate determination. Within 8 hours after the
sample is taken, analyze it for percent CO2 and percent O2 using
either an Orsat analyzer or a Fyrite type combustion gas analyzer
according to section 11.3.
Note:
When using an Orsat analyzer, periodic Fyrite readings may be
taken to verify/confirm the results obtained from the Orsat.
8.3 Multi-Point, Integrated Sampling Procedure.
8.3.1 Unless otherwise specified in an applicable regulation, or
by the Administrator, a minimum of eight traverse points shall be
used for circular stacks having diameters less than 0.61 m (24
in.), a minimum of nine shall be used for rectangular stacks having
equivalent diameters less than 0.61 m (24 in.), and a minimum of 12
traverse points shall be used for all other cases. The traverse
points shall be located according to Method 1.
8.3.2 Follow the procedures outlined in sections 8.2.2 through
8.2.4, except for the following: Traverse all sampling points, and
sample at each point for an equal length of time. Record sampling
data as shown in Figure 3-3.
9.0 Quality Control
Section
Quality control measure
Effect
8.2
Use of Fyrite to confirm Orsat
results
Ensures the accurate
measurement of CO2 and O2.
10.1
Periodic audit of analyzer and
operator technique
Ensures that the analyzer is
operating properly and that the operator performs the sampling
procedure correctly and accurately.
11.3
Replicable analyses of
integrated samples
Minimizes experimental
error.
10.0 Calibration and Standardization
10.1 Analyzer. The analyzer and analyzer operator's technique
should be audited periodically as follows: take a sample from a
manifold containing a known mixture of CO2 and O2, and analyze
according to the procedure in section 11.3. Repeat this procedure
until the measured concentration of three consecutive samples
agrees with the stated value ±0.5 percent. If necessary, take
corrective action, as specified in the analyzer users manual.
10.2 Rotameter. The rotameter need not be calibrated, but should
be cleaned and maintained according to the manufacturer's
instruction.
11.0 Analytical Procedure
11.1 Maintenance. The Orsat or Fyrite-type analyzer should be
maintained and operated according to the manufacturers
specifications.
11.2 Grab Sample Analysis. Use either an Orsat analyzer or a
Fyrite-type combustion gas analyzer to measure O2 and CO2
concentration for dry molecular weight determination, using
procedures as specified in the analyzer user's manual. If an Orsat
analyzer is used, it is recommended that the Orsat leak-check,
described in section 11.5, be performed before this determination;
however, the check is optional. Calculate the dry molecular weight
as indicated in section 12.0. Repeat the sampling, analysis, and
calculation procedures until the dry molecular weights of any three
grab samples differ from their mean by no more than 0.3 g/g-mole
(0.3 lb/lb-mole). Average these three molecular weights, and report
the results to the nearest 0.1 g/g-mole (0.1 lb/lb-mole).
11.3 Integrated Sample Analysis. Use either an Orsat analyzer or
a Fyrite-type combustion gas analyzer to measure O2 and CO2
concentration for dry molecular weight determination, using
procedures as specified in the analyzer user's manual. If an Orsat
analyzer is used, it is recommended that the Orsat leak-check,
described in section 11.5, be performed before this determination;
however, the check is optional. Calculate the dry molecular weight
as indicated in section 12.0. Repeat the analysis and calculation
procedures until the individual dry molecular weights for any three
analyses differ from their mean by no more than 0.3 g/g-mole (0.3
lb/lb-mole). Average these three molecular weights, and report the
results to the nearest 0.1 g/g-mole (0.1 lb/lb-mole).
11.4 Standardization. A periodic check of the reagents and of
operator technique should be conducted at least once every three
series of test runs as outlined in section 10.1.
11.5 Leak-Check Procedure for Orsat Analyzer. Moving an Orsat
analyzer frequently causes it to leak. Therefore, an Orsat analyzer
should be thoroughly leak-checked on site before the flue gas
sample is introduced into it. The procedure for leak-checking an
Orsat analyzer is as follows:
11.5.1 Bring the liquid level in each pipette up to the
reference mark on the capillary tubing, and then close the pipette
stopcock.
11.5.2 Raise the leveling bulb sufficiently to bring the
confining liquid meniscus onto the graduated portion of the
burette, and then close the manifold stopcock.
11.5.3 Record the meniscus position.
11.5.4 Observe the meniscus in the burette and the liquid level
in the pipette for movement over the next 4 minutes.
11.5.5 For the Orsat analyzer to pass the leak-check, two
conditions must be met:
11.5.5.1 The liquid level in each pipette must not fall below
the bottom of the capillary tubing during this 4-minute
interval.
11.5.5.2 The meniscus in the burette must not change by more
than 0.2 ml during this 4-minute interval.
11.5.6 If the analyzer fails the leak-check procedure, check all
rubber connections and stopcocks to determine whether they might be
the cause of the leak. Disassemble, clean, and regrease any leaking
stopcocks. Replace leaking rubber connections. After the analyzer
is reassembled, repeat the leak-check procedure.
12.0 Calculations and Data Analysis
12.1 Nomenclature.
Md = Dry molecular weight, g/g-mole (lb/lb-mole). %CO2 = Percent
CO2 by volume, dry basis. %O2 = Percent O2 by volume, dry basis.
%CO = Percent CO by volume, dry basis. %N2 = Percent N2 by volume,
dry basis. 0.280 = Molecular weight of N2 or CO, divided by 100.
0.320 = Molecular weight of O2 divided by 100. 0.440 = Molecular
weight of CO2 divided by 100.
12.2 Nitrogen, Carbon Monoxide Concentration. Determine the
percentage of the gas that is N2 and CO by subtracting the sum of
the percent CO2 and percent O2 from 100 percent.
12.3 Dry Molecular Weight. Use Equation 3-1 to calculate the dry
molecular weight of the stack gas.
Note:
The above Equation 3-1 does not consider the effect on
calculated dry molecular weight of argon in the effluent gas. The
concentration of argon, with a molecular weight of 39.9, in ambient
air is about 0.9 percent. A negative error of approximately 0.4
percent is introduced. The tester may choose to include argon in
the analysis using procedures subject to approval of the
Administrator.
1. Altshuller, A.P. Storage of Gases and Vapors in Plastic Bags.
International Journal of Air and Water Pollution. 6:75-81.
1963.
2. Conner, William D. and J.S. Nader. Air Sampling with Plastic
Bags. Journal of the American Industrial Hygiene Association.
25:291-297. 1964.
3. Burrell Manual for Gas Analysts, Seventh edition. Burrell
Corporation, 2223 Fifth Avenue, Pittsburgh, PA. 15219. 1951.
4. Mitchell, W.J. and M.R. Midgett. Field Reliability of the
Orsat Analyzer. Journal of Air Pollution Control Association.
26:491-495. May 1976.
5. Shigehara, R.T., R.M. Neulicht, and W.S. Smith. Validating
Orsat Analysis Data from Fossil Fuel-Fired Units. Stack Sampling
News. 4(2):21-26. August 1976.
17.0 Tables, Diagrams, Flowcharts, and Validation Data
Time
Traverse point
Q (liter/min)
% Deviation a
Average
a % Dev.=[(Q−Qavg)/Qavg] × 100
(Must be ≤±10%)
Figure 3-3. Sampling Rate Data Method 3A - Determination of Oxygen
and Carbon Dioxide Concentrations in Emissions From Stationary
Sources (Instrumental Analyzer Procedure) 1.0 Scope and Application
What is Method 3A?
Method 3A is a procedure for measuring oxygen (O2) and carbon
dioxide (CO2) in stationary source emissions using a continuous
instrumental analyzer. Quality assurance and quality control
requirements are included to assure that you, the tester, collect
data of known quality. You must document your adherence to these
specific requirements for equipment, supplies, sample collection
and analysis, calculations, and data analysis.
This method does not completely describe all equipment,
supplies, and sampling and analytical procedures you will need but
refers to other methods for some of the details. Therefore, to
obtain reliable results, you should also have a thorough knowledge
of these additional test methods which are found in appendix A to
this part:
(a) Method 1 - Sample and Velocity Traverses for Stationary
Sources.
(b) Method 3 - Gas Analysis for the Determination of Molecular
Weight.
(c) Method 4 - Determination of Moisture Content in Stack
Gases.
(d) Method 7E - Determination of Nitrogen Oxides Emissions from
Stationary Sources (Instrumental Analyzer Procedure).
1.1 Analytes. What does this method determine? This
method measures the concentration of oxygen and carbon dioxide.
Analyte
CAS No.
Sensitivity
Oxygen (O2)
7782-44-7
Typically <2% of
Calibration Span.
Carbon dioxide
(CO2)
124-38-9
Typically <2% of
Calibration Span.
1.2 Applicability. When is this method required? The use
of Method 3A may be required by specific New Source Performance
Standards, Clean Air Marketing rules, State Implementation Plans
and permits, where measurements of O2 and CO2 concentrations in
stationary source emissions must be made, either to determine
compliance with an applicable emission standard or to conduct
performance testing of a continuous emission monitoring system
(CEMS). Other regulations may also require the use of Method
3A.
1.3 Data Quality Objectives. How good must my collected data
be? Refer to section 1.3 of Method 7E.
2.0 Summary of Method
In this method, you continuously or intermittently sample the
effluent gas and convey the sample to an analyzer that measures the
concentration of O2 or CO2. You must meet the performance
requirements of this method to validate your data.
3.0 Definitions
Refer to section 3.0 of Method 7E for the applicable
definitions.
4.0 Interferences [Reserved] 5.0 Safety
Refer to section 5.0 of Method 7E.
6.0 Equipment and Supplies
Figure 7E-1 in Method 7E is a schematic diagram of an acceptable
measurement system.
6.1 What do I need for the measurement system? The
components of the measurement system are described (as applicable)
in sections 6.1 and 6.2 of Method 7E, except that the analyzer
described in section 6.2 of this method must be used instead of the
analyzer described in Method 7E. You must follow the noted
specifications in section 6.1 of Method 7E except that the
requirements to use stainless steel, Teflon, or non-reactive glass
filters do not apply. Also, a heated sample line is not required to
transport dry gases or for systems that measure the O2 or CO2
concentration on a dry basis, provided that the system is not also
being used to concurrently measure SO2 and/or NOX.
6.2 What analyzer must I use? You must use an analyzer
that continuously measures O2 or CO2 in the gas stream and meets
the specifications in section 13.0.
7.0 Reagents and Standards
7.1 Calibration Gas. What calibration gases do I need?
Refer to Section 7.1 of Method 7E for the calibration gas
requirements. Example calibration gas mixtures are listed below.
Pre-cleaned or scrubbed air may be used for the O2 high-calibration
gas provided it does not contain other gases that interfere with
the O2 measurement.
(a) CO2 in Nitrogen (N2).
(b) CO2/SO2 gas mixture in N2.
(c) O2/SO2 gas mixture in N2.
(d) O2/CO2/SO2 gas mixture in N2.
(e) CO2/NOX gas mixture in N2.
(f) CO2/SO2/NOX gas mixture in N2.
The tests for analyzer calibration error and system bias require
high-, mid-, and low-level gases.
7.2 Interference Check. What reagents do I need for the
interference check? Potential interferences may vary among
available analyzers. Table 7E-3 of Method 7E lists a number of
gases that should be considered in conducting the interference
test.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Sampling Site and Sampling Points. You must follow
the procedures of section 8.1 of Method 7E to determine the
appropriate sampling points, unless you are using Method 3A only to
determine the stack gas molecular weight and for no other purpose.
In that case, you may use single-point integrated sampling as
described in section 8.2.1 of Method 3. If the stratification test
provisions in section 8.1.2 of Method 7E are used to reduce the
number of required sampling points, the alternative acceptance
criterion for 3-point sampling will be ±0.5 percent CO2 or O2, and
the alternative acceptance criterion for single-point sampling will
be ±0.3 percent CO2 or O2. In that case, you may use single-point
integrated sampling as described in section 8.2.1 of Method 3.
8.2 Initial Measurement System Performance Tests. You
must follow the procedures in section 8.2 of Method 7E. If a
dilution-type measurement system is used, the special
considerations in section 8.3 of Method 7E apply.
8.3 Interference Check. The O2 or CO2 analyzer must be
documented to show that interference effects to not exceed 2.5
percent of the calibration span. The interference test in section
8.2.7 of Method 7E is a procedure that may be used to show this.
The effects of all potential interferences at the concentrations
encountered during testing must be addressed and documented. This
testing and documentation may be done by the instrument
manufacturer.
8.4 Sample Collection. You must follow the procedures in
section 8.4 of Method 7E.
8.5 Post-Run System Bias Check and Drift Assessment. You
must follow the procedures in section 8.5 of Method 7E.
9.0 Quality Control
Follow quality control procedures in section 9.0 of Method
7E.
10.0 Calibration and Standardization
Follow the procedures for calibration and standardization in
section 10.0 of Method 7E.
11.0 Analytical Procedures
Because sample collection and analysis are performed together
(see section 8), additional discussion of the analytical procedure
is not necessary.
12.0 Calculations and Data Analysis
You must follow the applicable procedures for calculations and
data analysis in section 12.0 of Method 7E, substituting percent O2
and percent CO2 for ppmv of NOX as appropriate.
13.0 Method Performance
The specifications for the applicable performance checks are the
same as in section 13.0 of Method 7E except for the alternative
specifications for system bias, drift, and calibration error. In
these alternative specifications, replace the term “0.5 ppmv” with
the term “0.5 percent O2” or “0.5 percent CO2” (as applicable).
1. “EPA Traceability Protocol for Assay and Certification of
Gaseous Calibration Standards” September 1997 as amended,
EPA-600/R-97/121.
18.0 Tables, Diagrams, Flowcharts, and Validation Data
Refer to section 18.0 of Method 7E.
Method 3B - Gas Analysis for the Determination of Emission Rate
Correction Factor or Excess Air Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling) essential to its performance. Some material is
incorporated by reference from other methods in this part.
Therefore, to obtain reliable results, persons using this method
should have a thorough knowledge of at least the following
additional test methods: Method 1 and 3.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Oxygen (O2)
7782-44-7
2,000 ppmv.
Carbon Dioxide
(CO2)
124-38-9
2,000 ppmv.
Carbon Monoxide
(CO)
630-08-0
N/A.
1.2 Applicability. This method is applicable for the
determination of O2, CO2, and CO concentrations in the effluent
from fossil-fuel combustion processes for use in excess air or
emission rate correction factor calculations. Where compounds other
than CO2, O2, CO, and nitrogen (N2) are present in concentrations
sufficient to affect the results, the calculation procedures
presented in this method must be modified, subject to the approval
of the Administrator.
1.3 Other methods, as well as modifications to the procedure
described herein, are also applicable for all of the above
determinations. Examples of specific methods and modifications
include: (1) A multi-point sampling method using an Orsat analyzer
to analyze individual grab samples obtained at each point, and (2)
a method using CO2 or O2 and stoichiometric calculations to
determine excess air. These methods and modifications may be used,
but are subject to the approval of the Administrator.
1.4 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A gas sample is extracted from a stack by one of the
following methods: (1) Single-point, grab sampling; (2)
single-point, integrated sampling; or (3) multi-point, integrated
sampling. The gas sample is analyzed for percent CO2, percent O2,
and, if necessary, percent CO using an Orsat combustion gas
analyzer.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Several compounds can interfere, to varying degrees, with
the results of Orsat analyses. Compounds that interfere with CO2
concentration measurement include acid gases (e.g., sulfur
dioxide, hydrogen chloride); compounds that interfere with O2
concentration measurement include unsaturated hydrocarbons
(e.g., acetone, acetylene), nitrous oxide, and ammonia.
Ammonia reacts chemically with the O2 absorbing solution, and when
present in the effluent gas stream must be removed before
analysis.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Corrosive Reagents. A typical Orsat analyzer requires four
reagents: a gas-confining solution, CO2 absorbent, O2 absorbent,
and CO absorbent. These reagents may contain potassium hydroxide,
sodium hydroxide, cuprous chloride, cuprous sulfate, alkaline
pyrogallic acid, and/or chromous chloride. Follow manufacturer's
operating instructions and observe all warning labels for reagent
use.
6.0 Equipment and Supplies Note:
As an alternative to the sampling apparatus and systems
described herein, other sampling systems (e.g., liquid
displacement) may be used, provided such systems are capable of
obtaining a representative sample and maintaining a constant
sampling rate, and are, otherwise, capable of yielding acceptable
results. Use of such systems is subject to the approval of the
Administrator.
6.1 Grab Sampling and Integrated Sampling. Same as in sections
6.1 and 6.2, respectively for Method 3.
6.2 Analysis. An Orsat analyzer only. For low CO2 (less than 4.0
percent) or high O2 (greater than 15.0 percent) concentrations, the
measuring burette of the Orsat must have at least 0.1 percent
subdivisions. For Orsat maintenance and operation procedures,
follow the instructions recommended by the manufacturer, unless
otherwise specified herein.
7.0 Reagents and Standards
7.1 Reagents. Same as in Method 3, section 7.1.
7.2 Standards. Same as in Method 3, section 7.2.
8.0 Sample Collection, Preservation, Storage, and Transport Note:
Each of the three procedures below shall be used only when
specified in an applicable subpart of the standards. The use of
these procedures for other purposes must have specific prior
approval of the Administrator. A Fyrite-type combustion gas
analyzer is not acceptable for excess air or emission rate
correction factor determinations, unless approved by the
Administrator. If both percent CO2 and percent O2 are measured, the
analytical results of any of the three procedures given below may
also be used for calculating the dry molecular weight (see Method
3).
8.1 Single-Point, Grab Sampling and Analytical Procedure.
8.1.1 The sampling point in the duct shall either be at the
centroid of the cross section or at a point no closer to the walls
than 1.0 m (3.3 ft), unless otherwise specified by the
Administrator.
8.1.2 Set up the equipment as shown in Figure 3-1 of Method 3,
making sure all connections ahead of the analyzer are tight.
Leak-check the Orsat analyzer according to the procedure described
in section 11.5 of Method 3. This leak-check is mandatory.
8.1.3 Place the probe in the stack, with the tip of the probe
positioned at the sampling point; purge the sampling line long
enough to allow at least five exchanges. Draw a sample into the
analyzer. For emission rate correction factor determinations,
immediately analyze the sample for percent CO2 or percent O2, as
outlined in section 11.2. For excess air determination, immediately
analyze the sample for percent CO2, O2, and CO, as outlined in
section 11.2, and calculate excess air as outlined in section
12.2.
8.1.4 After the analysis is completed, leak-check (mandatory)
the Orsat analyzer once again, as described in section 11.5 of
Method 3. For the results of the analysis to be valid, the Orsat
analyzer must pass this leak-test before and after the
analysis.
8.2 Single-Point, Integrated Sampling and Analytical
Procedure.
8.2.1 The sampling point in the duct shall be located as
specified in section 8.1.1.
8.2.2 Leak-check (mandatory) the flexible bag as in section
6.2.6 of Method 3. Set up the equipment as shown in Figure 3-2 of
Method 3. Just before sampling, leak-check (mandatory) the train by
placing a vacuum gauge at the condenser inlet, pulling a vacuum of
at least 250 mm Hg (10 in. Hg), plugging the outlet at the quick
disconnect, and then turning off the pump. The vacuum should remain
stable for at least 0.5 minute. Evacuate the flexible bag. Connect
the probe, and place it in the stack, with the tip of the probe
positioned at the sampling point; purge the sampling line. Next,
connect the bag, and make sure that all connections are tight.
8.2.3 Sample at a constant rate, or as specified by the
Administrator. The sampling run must be simultaneous with, and for
the same total length of time as, the pollutant emission rate
determination. Collect at least 28 liters (1.0 ft 3) of sample gas.
Smaller volumes may be collected, subject to approval of the
Administrator.
8.2.4 Obtain one integrated flue gas sample during each
pollutant emission rate determination. For emission rate correction
factor determination, analyze the sample within 4 hours after it is
taken for percent CO2 or percent O2 (as outlined in section
11.2).
8.3 Multi-Point, Integrated Sampling and Analytical
Procedure.
8.3.1 Unless otherwise specified in an applicable regulation, or
by the Administrator, a minimum of eight traverse points shall be
used for circular stacks having diameters less than 0.61 m (24
in.), a minimum of nine shall be used for rectangular stacks having
equivalent diameters less than 0.61 m (24 in.), and a minimum of 12
traverse points shall be used for all other cases. The traverse
points shall be located according to Method 1.
8.3.2 Follow the procedures outlined in sections 8.2.2 through
8.2.4, except for the following: Traverse all sampling points, and
sample at each point for an equal length of time. Record sampling
data as shown in Figure 3-3 of Method 3.
9.0 Quality Control
9.1 Data Validation Using Fuel Factor. Although in most
instances, only CO2 or O2 measurement is required, it is
recommended that both CO2 and O2 be measured to provide a check on
the quality of the data. The data validation procedure of section
12.3 is suggested.
Note:
Since this method for validating the CO2 and O2 analyses is
based on combustion of organic and fossil fuels and dilution of the
gas stream with air, this method does not apply to sources that (1)
remove CO2 or O2 through processes other than combustion, (2) add
O2 (e.g., oxygen enrichment) and N2 in proportions different
from that of air, (3) add CO2 (e.g., cement or lime kilns),
or (4) have no fuel factor, FO, values obtainable (e.g.,
extremely variable waste mixtures). This method validates the
measured proportions of CO2 and O2 for fuel type, but the method
does not detect sample dilution resulting from leaks during or
after sample collection. The method is applicable for samples
collected downstream of most lime or limestone flue-gas
desulfurization units as the CO2 added or removed from the gas
stream is not significant in relation to the total CO2
concentration. The CO2 concentrations from other types of scrubbers
using only water or basic slurry can be significantly affected and
would render the fuel factor check minimally useful.
10.0 Calibration and Standardization
10.1 Analyzer. The analyzer and analyzer operator technique
should be audited periodically as follows: take a sample from a
manifold containing a known mixture of CO2 and O2, and analyze
according to the procedure in section 11.3. Repeat this procedure
until the measured concentration of three consecutive samples
agrees with the stated value ±0.5 percent. If necessary, take
corrective action, as specified in the analyzer users manual.
10.2 Rotameter. The rotameter need not be calibrated, but should
be cleaned and maintained according to the manufacturer's
instruction.
11.0 Analytical Procedure
11.1 Maintenance. The Orsat analyzer should be maintained
according to the manufacturers specifications.
11.2 Grab Sample Analysis. To ensure complete absorption of the
CO2, O2, or if applicable, CO, make repeated passes through each
absorbing solution until two consecutive readings are the same.
Several passes (three or four) should be made between readings. (If
constant readings cannot be obtained after three consecutive
readings, replace the absorbing solution.) Although in most cases,
only CO2 or O2 concentration is required, it is recommended that
both CO2 and O2 be measured, and that the procedure in section 12.3
be used to validate the analytical data.
Note:
Since this single-point, grab sampling and analytical procedure
is normally conducted in conjunction with a single-point, grab
sampling and analytical procedure for a pollutant, only one
analysis is ordinarily conducted. Therefore, great care must be
taken to obtain a valid sample and analysis.
11.3 Integrated Sample Analysis. The Orsat analyzer must be
leak-checked (see section 11.5 of Method 3) before the analysis. If
excess air is desired, proceed as follows: (1) within 4 hours after
the sample is taken, analyze it (as in sections 11.3.1 through
11.3.3) for percent CO2, O2, and CO; (2) determine the percentage
of the gas that is N2 by subtracting the sum of the percent CO2,
percent O2, and percent CO from 100 percent; and (3) calculate
percent excess air, as outlined in section 12.2.
11.3.1 To ensure complete absorption of the CO2, O2, or if
applicable, CO, follow the procedure described in section 11.2.
Note:
Although in most instances only CO2 or O2 is required, it is
recommended that both CO2 and O2 be measured, and that the
procedures in section 12.3 be used to validate the analytical
data.
11.3.2 Repeat the analysis until the following criteria are
met:
11.3.2.1 For percent CO2, repeat the analytical procedure until
the results of any three analyses differ by no more than (a) 0.3
percent by volume when CO2 is greater than 4.0 percent or (b) 0.2
percent by volume when CO2 is less than or equal to 4.0 percent.
Average three acceptable values of percent CO2, and report the
results to the nearest 0.2 percent.
11.3.2.2 For percent O2, repeat the analytical procedure until
the results of any three analyses differ by no more than (a) 0.3
percent by volume when O2 is less than 15.0 percent or (b) 0.2
percent by volume when O2 is greater than or equal to 15.0 percent.
Average the three acceptable values of percent O2, and report the
results to the nearest 0.1 percent.
11.3.2.3 For percent CO, repeat the analytical procedure until
the results of any three analyses differ by no more than 0.3
percent. Average the three acceptable values of percent CO, and
report the results to the nearest 0.1 percent.
11.3.3 After the analysis is completed, leak-check (mandatory)
the Orsat analyzer once again, as described in section 11.5 of
Method 3. For the results of the analysis to be valid, the Orsat
analyzer must pass this leak-test before and after the
analysis.
11.4 Standardization. A periodic check of the reagents and of
operator technique should be conducted at least once every three
series of test runs as indicated in section 10.1.
12.0 Calculations and Data Analysis
12.1 Nomenclature. Same as section 12.1 of Method 3 with the
addition of the following:
%EA = Percent excess air. 0.264 = Ratio of O2 to N2 in air, v/v.
12.2 Percent Excess Air. Determine the percentage of the gas
that is N2 by subtracting the sum of the percent CO2, percent CO,
and percent O2 from 100 percent. Calculate the percent excess air
(if applicable) by substituting the appropriate values of percent
O2, CO, and N2 into Equation 3B-1.
Note:
The equation above assumes that ambient air is used as the
source of O2 and that the fuel does not contain appreciable amounts
of N2 (as do coke oven or blast furnace gases). For those cases
when appreciable amounts of N2 are present (coal, oil, and natural
gas do not contain appreciable amounts of N2) or when oxygen
enrichment is used, alternative methods, subject to approval of the
Administrator, are required.
12.3 Data Validation When Both CO2 and O2 Are Measured.
12.3.1 Fuel Factor, Fo. Calculate the fuel factor (if
applicable) using Equation 3B-2:
Where: %O2 = Percent O2 by volume, dry basis.
%CO2 = Percent CO2 by volume, dry basis. 20.9 = Percent O2 by
volume in ambient air.
If CO is present in quantities measurable by this method, adjust
the O2 and CO2 values using Equations 3B-3 and 3B-4 before
performing the calculation for Fo:
Where: %CO = Percent CO by
volume, dry basis.
12.3.2 Compare the calculated Fo factor with the expected Fo
values. Table 3B-1 in section 17.0 may be used in establishing
acceptable ranges for the expected Fo if the fuel being burned is
known. When fuels are burned in combinations, calculate the
combined fuel Fd and Fc factors (as defined in Method 19, section
12.2) according to the procedure in Method 19, sections 12.2 and
12.3. Then calculate the Fo factor according to Equation 3B-5.
12.3.3 Calculated Fo values, beyond the acceptable ranges shown
in this table, should be investigated before accepting the test
results. For example, the strength of the solutions in the gas
analyzer and the analyzing technique should be checked by sampling
and analyzing a known concentration, such as air; the fuel factor
should be reviewed and verified. An acceptability range of ±12
percent is appropriate for the Fo factor of mixed fuels with
variable fuel ratios. The level of the emission rate relative to
the compliance level should be considered in determining if a
retest is appropriate; i.e., if the measured emissions are much
lower or much greater than the compliance limit, repetition of the
test would not significantly change the compliance status of the
source and would be unnecessarily time consuming and costly.
17.0 Tables, Diagrams, Flowcharts, and Validation Data
Table 3B-1 - Fo Factors for Selected
Fuels
Fuel type
Fo range
Coal:
Anthracite and
lignite
1.016-1.130
Bituminous
1.083-1.230
Oil:
Distillate
1.260-1.413
Residual
1.210-1.370
Gas:
Natural
1.600-1.836
Propane
1.434-1.586
Butane
1.405-1.553
Wood
1.000-1.120
Wood bark
1.003-1.130
Method 3C - Determination of Carbon Dioxide, Methane, Nitrogen, and
Oxygen From Stationary Sources 1. Applicability and Principle
1.1 Applicability. This method applies to the analysis of carbon
dioxide (CO2), methane (CH4), nitrogen (N2), and oxygen (O2) in
samples from municipal solid waste landfills and other sources when
specified in an applicable subpart.
1.2 Principle. A portion of the sample is injected into a gas
chromatograph (GC) and the CO2, CH4, N2, and O2 concentrations are
determined by using a thermal conductivity detector (TCD) and
integrator.
2. Range and Sensitivity
2.1 Range. The range of this method depends upon the
concentration of samples. The analytical range of TCD's is
generally between approximately 10 ppmv and the upper percent
range.
2.2 Sensitivity. The sensitivity limit for a compound is defined
as the minimum detectable concentration of that compound, or the
concentration that produces a signal-to-noise ratio of three to
one. For CO2, CH4, N2, and O2, the sensitivity limit is in the low
ppmv range.
3. Interferences
Since the TCD exhibits universal response and detects all gas
components except the carrier, interferences may occur. Choosing
the appropriate GC or shifting the retention times by changing the
column flow rate may help to eliminate resolution
interferences.
To assure consistent detector response, helium is used to
prepare calibration gases. Frequent exposure to samples or carrier
gas containing oxygen may gradually destroy filaments.
4. Apparatus
4.1 Gas Chromatograph. GC having at least the following
components:
4.1.1 Separation Column. Appropriate column(s) to resolve CO2,
CH4, N2, O2, and other gas components that may be present in the
sample.
4.1.2 Sample Loop. Teflon or stainless steel tubing of the
appropriate diameter.
Note:
Mention of trade names or specific products does not constitute
endorsement or recommendation by the U. S. Environmental Protection
Agency.
4.1.3 Conditioning System. To maintain the column and sample
loop at constant temperature.
4.1.4 Thermal Conductivity Detector.
4.2 Recorder. Recorder with linear strip chart. Electronic
integrator (optional) is recommended.
4.3 Teflon Tubing. Diameter and length determined by connection
requirements of cylinder regulators and the GC.
4.4 Regulators. To control gas cylinder pressures and flow
rates.
4.5 Adsorption Tubes. Applicable traps to remove any O2 from the
carrier gas.
5. Reagents
5.1 Calibration and Linearity Gases. Standard cylinder gas
mixtures for each compound of interest with at least three
concentration levels spanning the range of suspected sample
concentrations. The calibration gases shall be prepared in
helium.
5.2 Carrier Gas. Helium, high-purity.
6. Analysis
6.1 Sample Collection. Use the sample collection procedures
described in Methods 3 or 25C to collect a sample of landfill gas
(LFG).
6.2 Preparation of GC. Before putting the GC analyzer into
routine operation, optimize the operational conditions according to
the manufacturer's specifications to provide good resolution and
minimum analysis time. Establish the appropriate carrier gas flow
and set the detector sample and reference cell flow rates at
exactly the same levels. Adjust the column and detector
temperatures to the recommended levels. Allow sufficient time for
temperature stabilization. This may typically require 1 hour for
each change in temperature.
6.3 Analyzer Linearity Check and Calibration. Perform this test
before sample analysis.
6.3.1 Using the gas mixtures in section 5.1, verify the detector
linearity over the range of suspected sample concentrations with at
least three concentrations per compound of interest. This initial
check may also serve as the initial instrument calibration.
6.3.2 You may extend the use of the analyzer calibration by
performing a single-point calibration verification. Calibration
verifications shall be performed by triplicate injections of a
single-point standard gas. The concentration of the single-point
calibration must either be at the midpoint of the calibration curve
or at approximately the source emission concentration measured
during operation of the analyzer.
6.3.3 Triplicate injections must agree within 5 percent of their
mean, and the average calibration verification point must agree
within 10 percent of the initial calibration response factor. If
these calibration verification criteria are not met, the initial
calibration described in section 6.3.1, using at least three
concentrations, must be repeated before analysis of samples can
continue.
6.3.4 For each instrument calibration, record the carrier and
detector flow rates, detector filament and block temperatures,
attenuation factor, injection time, chart speed, sample loop
volume, and component concentrations.
6.3.5 Plot a linear regression of the standard concentrations
versus area values to obtain the response factor of each compound.
Alternatively, response factors of uncorrected component
concentrations (wet basis) may be generated using instrumental
integration.
Note:
Peak height may be used instead of peak area throughout this
method.
6.4 Sample Analysis. Purge the sample loop with sample, and
allow to come to atmospheric pressure before each injection.
Analyze each sample in duplicate, and calculate the average sample
area (A). The results are acceptable when the peak areas for two
consecutive injections agree within 5 percent of their average. If
they do not agree, run additional samples until consistent area
data are obtained. Determine the tank sample concentrations
according to section 7.2.
7. Calculations
Carry out calculations retaining at least one extra decimal
figure beyond that of the acquired data. Round off results only
after the final calculation.
7.1 Nomenclature.
Bw = Moisture content in the sample, fraction. CN2 = Measured N2
concentration (by Method 3C), fraction. CN2Corr = Measured N2
concentration corrected only for dilution, fraction. Ct =
Calculated NMOC concentration, ppmv C equivalent. Ctm = Measured
NMOC concentration, ppmv C equivalent. Pb = Barometric pressure, mm
Hg. Pt = Gas sample tank pressure after sampling, but before
pressurizing, mm Hg absolute. Ptf = Final gas sample tank pressure
after pressurizing, mm Hg absolute. Pti = Gas sample tank pressure
after evacuation, mm Hg absolute. Pw = Vapor pressure of H2O (from
Table 25C-1), mm Hg. r = Total number of analyzer injections of
sample tank during analysis (where j = injection number, 1 . . .
r). R = Mean calibration response factor for specific sample
component, area/ppm. Tt = Sample tank temperature at completion of
sampling, °K. Tti = Sample tank temperature before sampling, °K.
Ttf = Sample tank temperature after pressurizing, °K.
7.2 Concentration of Sample Components. Calculate C for each
compound using Equations 3C-1 and 3C-2. Use the temperature and
barometric pressure at the sampling site to calculate Bw. If the
sample was diluted with helium using the procedures in Method 25C,
use Equation 3C-3 to calculate the concentration.
7.3 Measured N2 Concentration Correction. Calculate the reported
N2 correction for Method 25-C using Eq. 3C-4. If oxygen is
determined in place of N2, substitute the oxygen concentration for
the nitrogen concentration in the equation.
8.
Bibliography
1. McNair, H.M., and E.J. Bonnelli. Basic Gas Chromatography.
Consolidated Printers, Berkeley, CA. 1969.
[36 FR 24877, Dec. 23, 1971] Editorial Note:For Federal Register
citations affecting appendix A-2 to part 60, see the List of CFR
sections Affected, which appears in the Finding Aids section of the
printed volume and at www.govinfo.gov.
Appendix A-3 to Part 60 - Test Methods 4 through 5I
40:9.0.1.1.1.0.1.1.3 : Appendix A
Appendix A-3 to Part 60 - Test Methods 4 through 5I Method 4 -
Determination of moisture content in stack gases Method 5 -
Determination of particulate matter emissions from stationary
sources Method 5A - Determination of particulate matter emissions
from the asphalt processing and asphalt roofing industry Method 5B
- Determination of nonsulfuric acid particulate matter emissions
from stationary sources Method 5C [Reserved] Method 5D -
Determination of particulate matter emissions from positive
pressure fabric filters Method 5E - Determination of particulate
matter emissions from the wool fiberglass insulation manufacturing
industry Method 5F - Determination of nonsulfate particulate matter
emissions from stationary sources Method 5G - Determination of
particulate matter emissions from wood heaters (dilution tunnel
sampling location) Method 5H - Determination of particulate
emissions from wood heaters from a stack location Method 5I -
Determination of Low Level Particulate Matter Emissions From
Stationary Sources
The test methods in this appendix are referred to in § 60.8
(Performance Tests) and § 60.11 (Compliance With Standards and
Maintenance Requirements) of 40 CFR part 60, subpart A (General
Provisions). Specific uses of these test methods are described in
the standards of performance contained in the subparts, beginning
with Subpart D.
Within each standard of performance, a section title “Test
Methods and Procedures” is provided to: (1) Identify the test
methods to be used as reference methods to the facility subject to
the respective standard and (2) identify any special instructions
or conditions to be followed when applying a method to the
respective facility. Such instructions (for example, establish
sampling rates, volumes, or temperatures) are to be used either in
addition to, or as a substitute for procedures in a test method.
Similarly, for sources subject to emission monitoring requirements,
specific instructions pertaining to any use of a test method as a
reference method are provided in the subpart or in Appendix B.
Inclusion of methods in this appendix is not intended as an
endorsement or denial of their applicability to sources that are
not subject to standards of performance. The methods are
potentially applicable to other sources; however, applicability
should be confirmed by careful and appropriate evaluation of the
conditions prevalent at such sources.
The approach followed in the formulation of the test methods
involves specifications for equipment, procedures, and performance.
In concept, a performance specification approach would be
preferable in all methods because this allows the greatest
flexibility to the user. In practice, however, this approach is
impractical in most cases because performance specifications cannot
be established. Most of the methods described herein, therefore,
involve specific equipment specifications and procedures, and only
a few methods in this appendix rely on performance criteria.
Minor changes in the test methods should not necessarily affect
the validity of the results and it is recognized that alternative
and equivalent methods exist. section 60.8 provides authority for
the Administrator to specify or approve (1) equivalent methods, (2)
alternative methods, and (3) minor changes in the methodology of
the test methods. It should be clearly understood that unless
otherwise identified all such methods and changes must have prior
approval of the Administrator. An owner employing such methods or
deviations from the test methods without obtaining prior approval
does so at the risk of subsequent disapproval and retesting with
approved methods.
Within the test methods, certain specific equipment or
procedures are recognized as being acceptable or potentially
acceptable and are specifically identified in the methods. The
items identified as acceptable options may be used without approval
but must be identified in the test report. The potentially
approvable options are cited as “subject to the approval of the
Administrator” or as “or equivalent.” Such potentially approvable
techniques or alternatives may be used at the discretion of the
owner without prior approval. However, detailed descriptions for
applying these potentially approvable techniques or alternatives
are not provided in the test methods. Also, the potentially
approvable options are not necessarily acceptable in all
applications. Therefore, an owner electing to use such potentially
approvable techniques or alternatives is responsible for: (1)
assuring that the techniques or alternatives are in fact applicable
and are properly executed; (2) including a written description of
the alternative method in the test report (the written method must
be clear and must be capable of being performed without additional
instruction, and the degree of detail should be similar to the
detail contained in the test methods); and (3) providing any
rationale or supporting data necessary to show the validity of the
alternative in the particular application. Failure to meet these
requirements can result in the Administrator's disapproval of the
alternative.
Method 4 - Determination of Moisture Content in Stack Gases Note:
This method does not include all the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling) essential to its performance. Some material is
incorporated by reference from other methods in this part.
Therefore, to obtain reliable results, persons using this method
should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 5, and Method 6.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Water vapor
(H2O)
7732-18-5
N/A
1.2 Applicability. This method is applicable for the
determination of the moisture content of stack gas.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A gas sample is extracted at a constant rate from the
source; moisture is removed from the sample stream and determined
gravimetrically.
2.2 The method contains two possible procedures: a reference
method and an approximation method.
2.2.1 The reference method is used for accurate determinations
of moisture content (such as are needed to calculate emission
data). The approximation method, provides estimates of percent
moisture to aid in setting isokinetic sampling rates prior to a
pollutant emission measurement run. The approximation method
described herein is only a suggested approach; alternative means
for approximating the moisture content (e.g., drying tubes,
wet bulb-dry bulb techniques, condensation techniques,
stoichiometric calculations, previous experience, etc.) are also
acceptable.
2.2.2 The reference method is often conducted simultaneously
with a pollutant emission measurement run. When it is, calculation
of percent isokinetic, pollutant emission rate, etc., for the run
shall be based upon the results of the reference method or its
equivalent. These calculations shall not be based upon the results
of the approximation method, unless the approximation method is
shown, to the satisfaction of the Administrator, to be capable of
yielding results within one percent H2O of the reference
method.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 The moisture content of saturated gas streams or streams
that contain water droplets, as measured by the reference method,
may be positively biased. Therefore, when these conditions exist or
are suspected, a second determination of the moisture content shall
be made simultaneously with the reference method, as follows:
Assume that the gas stream is saturated. Attach a temperature
sensor [capable of measuring to ±1 °C (2 °F)] to the reference
method probe. Measure the stack gas temperature at each traverse
point (see section 8.1.1.1) during the reference method traverse,
and calculate the average stack gas temperature. Next, determine
the moisture percentage, either by: (1) Using a psychrometric chart
and making appropriate corrections if the stack pressure is
different from that of the chart, or (2) using saturation vapor
pressure tables. In cases where the psychrometric chart or the
saturation vapor pressure tables are not applicable (based on
evaluation of the process), alternative methods, subject to the
approval of the Administrator, shall be used.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies
6.1 Reference Method. A schematic of the sampling train used in
this reference method is shown in Figure 4-1.
6.1.1 Probe. Stainless steel or glass tubing, sufficiently
heated to prevent water condensation, and equipped with a filter,
either in-stack (e.g., a plug of glass wool inserted into
the end of the probe) or heated out-of-stack (e.g., as
described in Method 5), to remove particulate matter. When stack
conditions permit, other metals or plastic tubing may be used for
the probe, subject to the approval of the Administrator.
6.1.2 Condenser. Same as Method 5, section 6.1.1.8.
6.1.3 Cooling System. An ice bath container, crushed ice, and
water (or equivalent), to aid in condensing moisture.
6.1.4 Metering System. Same as in Method 5, section 6.1.1.9,
except do not use sampling systems designed for flow rates higher
than 0.0283 m 3/min (1.0 cfm). Other metering systems, capable of
maintaining a constant sampling rate to within 10 percent and
determining sample gas volume to within 2 percent, may be used,
subject to the approval of the Administrator.
6.1.5 Barometer and Balance. Same as Method 5, sections 6.1.2
and 6.2.5, respectively.
6.2. Approximation Method. A schematic of the sampling train
used in this approximation method is shown in Figure 4-2.
6.2.1 Probe. Same as section 6.1.1.
6.2.2 Condenser. Two midget impingers, each with 30-ml capacity,
or equivalent.
6.2.3 Cooling System. Ice bath container, crushed ice, and
water, to aid in condensing moisture in impingers.
6.2.4 Drying Tube. Tube packed with new or regenerated 6- to
16-mesh indicating-type silica gel (or equivalent desiccant), to
dry the sample gas and to protect the meter and pump.
6.2.5 Valve. Needle valve, to regulate the sample gas flow
rate.
6.2.6 Pump. Leak-free, diaphragm type, or equivalent, to pull
the gas sample through the train.
6.2.7 Volume Meter. Dry gas meter, sufficiently accurate to
measure the sample volume to within 2 percent, and calibrated over
the range of flow rates and conditions actually encountered during
sampling.
6.2.8 Rate Meter. Rotameter, or equivalent, to measure the flow
range from 0 to 3 liters/min (0 to 0.11 cfm).
6.2.9 Graduated Cylinder. 25-ml.
6.2.10 Barometer. Same as Method 5, section 6.1.2.
6.2.11 Vacuum Gauge. At least 760-mm (30-in.) Hg gauge, to be
used for the sampling leak check.
7.0 Reagents and Standards [Reserved] 8.0 Sample Collection,
Preservation, Transport, and Storage
8.1 Reference Method. The following procedure is intended for a
condenser system (such as the impinger system described in section
6.1.1.8 of Method 5) incorporating volumetric analysis to measure
the condensed moisture, and silica gel and gravimetric analysis to
measure the moisture leaving the condenser.
8.1.1 Preliminary Determinations.
8.1.1.1 Unless otherwise specified by the Administrator, a
minimum of eight traverse points shall be used for circular stacks
having diameters less than 0.61 m (24 in.), a minimum of nine
points shall be used for rectangular stacks having equivalent
diameters less than 0.61 m (24 in.), and a minimum of twelve
traverse points shall be used in all other cases. The traverse
points shall be located according to Method 1. The use of fewer
points is subject to the approval of the Administrator. Select a
suitable probe and probe length such that all traverse points can
be sampled. Consider sampling from opposite sides of the stack
(four total sampling ports) for large stacks, to permit use of
shorter probe lengths. Mark the probe with heat resistant tape or
by some other method to denote the proper distance into the stack
or duct for each sampling point.
8.1.1.2 Select a total sampling time such that a minimum total
gas volume of 0.60 scm (21 scf) will be collected, at a rate no
greater than 0.021 m 3/min (0.75 cfm). When both moisture content
and pollutant emission rate are to be determined, the moisture
determination shall be simultaneous with, and for the same total
length of time as, the pollutant emission rate run, unless
otherwise specified in an applicable subpart of the standards.
8.1.2 Preparation of Sampling Train.
8.1.2.1 Transfer water into the first two impingers, leave the
third impinger empty and add silica gel to the fourth impinger.
Weigh the impingers before sampling and record the weight to the
nearest 0.5g at a minimum.
8.1.2.2 Set up the sampling train as shown in Figure 4-1. Turn
on the probe heater and (if applicable) the filter heating system
to temperatures of approximately 120 °C (248 °F), to prevent water
condensation ahead of the condenser. Allow time for the
temperatures to stabilize. Place crushed ice and water in the ice
bath container.
8.1.3 Leak-Check Procedures.
8.1.3.1 Metering System. Same as Method 5, section 8.4.1.
8.1.3.2 Sampling Train. Disconnect the probe from the first
impinger or (if applicable) from the filter holder. Plug the inlet
to the first impinger (or filter holder), and pull a 380 mm (15
in.) Hg vacuum. A lower vacuum may be used, provided that it is not
exceeded during the test. A leakage rate in excess of 4 percent of
the average sampling rate or 0.00057 m 3/min (0.020 cfm), whichever
is less, is unacceptable. Following the leak check, reconnect the
probe to the sampling train.
8.1.4 Sampling Train Operation. During the sampling run,
maintain a sampling rate within 10 percent of constant rate, or as
specified by the Administrator. For each run, record the data
required on a data sheet similar to that shown in Figure 4-3. Be
sure to record the dry gas meter reading at the beginning and end
of each sampling time increment and whenever sampling is halted.
Take other appropriate readings at each sample point at least once
during each time increment.
Note:
When Method 4 is used concurrently with an isokinetic method
(e.g., Method 5) the sampling rate should be maintained at
isokinetic conditions rather than 10 percent of constant rate.
8.1.4.1 To begin sampling, position the probe tip at the first
traverse point. Immediately start the pump, and adjust the flow to
the desired rate. Traverse the cross section, sampling at each
traverse point for an equal length of time. Add more ice and, if
necessary, salt to maintain a temperature of less than 20 °C (68
°F) at the silica gel outlet.
8.1.4.2 At the end of the sample run, close the coarse adjust
valve, remove the probe and nozzle from the stack, turn off the
pump, record the final DGM meter reading, and conduct a post-test
leak check, as outlined in section 8.1.3.4.
8.2 Approximation Method.
Note:
The approximation method described below is presented only as a
suggested method (see section 2.0).
8.2.1 Place exactly 5 ml water in each impinger. Leak check the
sampling train as follows: Temporarily insert a vacuum gauge at or
near the probe inlet. Then, plug the probe inlet and pull a vacuum
of at least 250 mm (10 in.) Hg. Note the time rate of change of the
dry gas meter dial; alternatively, a rotameter (0 to 40 ml/min) may
be temporarily attached to the dry gas meter outlet to determine
the leakage rate. A leak rate not in excess of 2 percent of the
average sampling rate is acceptable.
Note:
Release the probe inlet plug slowly before turning off the
pump.
8.2.2 Connect the probe, insert it into the stack, and sample at
a constant rate of 2 liters/min (0.071 cfm). Continue sampling
until the dry gas meter registers about 30 liters (1.1 ft 3) or
until visible liquid droplets are carried over from the first
impinger to the second. Record temperature, pressure, and dry gas
meter readings as indicated by Figure 4-4.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
Section
8.1.3.2.2
Leak rate of the sampling
system cannot exceed four percent of the average sampling rate or
0.00057 m 3/min (0.020 cfm)
Ensures the accuracy of the
volume of gas sampled. (Reference Method).
Section 8.2.1
Leak rate of the sampling
system cannot exceed two percent of the average sampling rate
Ensures the accuracy of the
volume of gas sampled. (Approximation Method).
9.2 Volume Metering System Checks. Same as Method 5, section
9.2.
10.0 Calibration and Standardization Note:
Maintain a laboratory log of all calibrations.
10.1 Reference Method. Calibrate the metering system,
temperature sensors, and barometer according to Method 5, sections
10.3, 10.5, and 10.6, respectively.
10.2 Approximation Method. Calibrate the metering system and the
barometer according to Method 6, section 10.1 and Method 5, section
10.6, respectively.
10.3 Field Balance Calibration Check. Check the calibration of
the balance used to weigh impingers with a weight that is at least
500g or within 50g of a loaded impinger. The weight must be ASTM
E617-13 “Standard Specification for Laboratory Weights and
Precision Mass Standards” (incorporated by reference-see 40 CFR
60.17) Class 6 (or better). Daily, before use, the field balance
must measure the weight within ± 0.5g of the certified mass. If the
daily balance calibration check fails, perform corrective measures
and repeat the check before using balance.
11.0 Analytical Procedure
11.1 Reference Method. Weigh the impingers after sampling and
record the difference in weight to the nearest 0.5 g at a minimum.
Determine the increase in weight of the silica gel (or silica gel
plus impinger) to the nearest 0.5 g at a minimum. Record this
information (see example data sheet, Figure 4-5), and calculate the
moisture content, as described in section 12.0.
11.2 Approximation Method. Weigh the contents of the two
impingers, and measure the weight to the nearest 0.5 g.
12.0 Data Analysis and Calculations
Carry out the following calculations, retaining at least one
extra significant figure beyond that of the acquired data. Round
off figures after final calculation.
12.1 Reference Method.
12.1.1 Nomenclature.
Bws = Proportion of water vapor, by volume, in the gas
stream.
Mw = Molecular weight of water, 18.015 g/g-mole (18.015
lb/lb-mole).
Pm = Absolute pressure (for this method, same as barometric
pressure) at the dry gas meter, mm Hg (in. Hg).
Pstd = Standard absolute pressure, 760 mm Hg (29.92 in. Hg).
R = Ideal gas constant, 0.06236 (mm Hg)(m 3)/(g-mole)(°K) for
metric units and 21.85 (in. Hg)(ft 3)/(lb-mole) (°R) for English
units.
Tm = Absolute temperature at meter, °K (°R).
Tstd = Standard absolute temperature, 293.15 °K (527.67 °R).
Vf = Final weight of condenser water plus impinger, g.
Vi = Initial weight, if any, of condenser water plus impinger,
g.
Vm = Dry gas volume measured by dry gas meter, dcm (dcf).
Vm(std) = Dry gas volume measured by the dry gas meter,
corrected to standard conditions, dscm (dscf).
Vwc(std) = Volume of water vapor condensed, corrected to
standard conditions, scm (scf).
Vwsg(std) = Volume of water vapor collected in silica gel,
corrected to standard conditions, scm (scf).
Wf = Final weight of silica gel or silica gel plus impinger,
g.
Wi = Initial weight of silica gel or silica gel plus impinger,
g.
Y = Dry gas meter calibration factor.
ΔVm = Incremental dry gas volume measured by dry gas meter at
each traverse point, dcm (dcf).
12.1.2 Volume of Water Vapor Condensed.
Where: K1
= 0.001335 m 3/g for metric units, = 0.04716 ft 3/g for English
units.
12.1.3
K3 = 0.001335 m 3/g for metric units, = 0.04716 ft 3/g for English
units.
12.1.4 Sample Gas Volume.
Where: K4 = 0.3855 °K/mm Hg for metric units, =
17.64 °R/in. Hg for English units. Note:
If the post-test leak rate (Section 8.1.4.2) exceeds the
allowable rate, correct the value of Vm in Equation 4-3, as
described in section 12.3 of Method 5.
12.1.5 Moisture Content.
12.1.6 Verification of Constant Sampling Rate. For each time
increment, determine the ΔVm. Calculate the average. If the value
for any time increment differs from the average by more than 10
percent, reject the results, and repeat the run.
12.1.7 In saturated or moisture droplet-laden gas streams, two
calculations of the moisture content of the stack gas shall be
made, one using a value based upon the saturated conditions (see
section 4.1), and another based upon the results of the impinger
analysis. The lower of these two values of Bws shall be considered
correct.
12.2 Approximation Method. The approximation method presented is
designed to estimate the moisture in the stack gas; therefore,
other data, which are only necessary for accurate moisture
determinations, are not collected. The following equations
adequately estimate the moisture content for the purpose of
determining isokinetic sampling rate settings.
12.2.1 Nomenclature.
Bwm = Approximate proportion by volume of water vapor in the gas
stream leaving the second impinger, 0.025.
Bws = Water vapor in the gas stream, proportion by volume.
Mw = Molecular weight of water, 18.015 g/g-mole (18.015
lb/lb-mole).
Pm = Absolute pressure (for this method, same as barometric
pressure) at the dry gas meter, mm Hg (in. Hg).
Pstd = Standard absolute pressure, 760 mm Hg (29.92 in. Hg).
R = Ideal gas constant, 0.06236 [(mm Hg)(m 3)]/[(g-mole)(K)] for
metric units and 21.85 [(in. Hg)(ft 3)]/[(lb-mole)(°R)] for English
units.
Tm = Absolute temperature at meter, °K (°R).
Tstd = Standard absolute temperature, 293.15 °K (527.67 °R).
Vf = Final weight of condenser water plus impinger, g.
Vi = Initial weight, if any, of condenser water plus impinger,
g.
Vm = Dry gas volume measured by dry gas meter, dcm (dcf).
Vm(std) = Dry gas volume measured by dry gas meter, corrected to
standard conditions, dscm (dscf).
Vwc(std) = Volume of water vapor condensed, corrected to
standard conditions, scm (scf).
Y = Dry gas meter calibration factor.
12.2.2 Volume of Water Vapor Collected.
K5 = 0.001335 m 3/g for metric units,
= 0.04716 ft 3/g for English units.
12.2.3 Sample Gas Volume.
Where: K6 = 0.3855 °K/mm Hg for metric units, =
17.64 °R/in. Hg for English units.
12.2.4 Approximate Moisture Content.
12.2.5 Using F-factors to determine approximate moisture for
estimating moisture content where no wet scrubber is being used,
for the purpose of determining isokinetic sampling rate settings
with no fuel sample, is acceptable using the average Fc or Fd
factor from Method 19 (see Method 19, section 12.3.1). If this
option is selected, calculate the approximate moisture as
follows:
Bws = BH + BA+ BF Where: BA = Mole
Fraction of moisture in the ambient air. Bws = Mole
fraction of moisture in the stack gas. Fd = Volume of dry
combustion components per unit of heat content at 0 percent oxygen,
dscf/10 6.
Btu (scm/J). See Table 19-2 in Method 19.
Fw = Volume of wet combustion components per unit of heat content
at 0 percent oxygen, wet.
scf/10 6 Btu (scm/J). See Table 19-2 in Method 19.
%RH = Percent relative humidity (calibrated hygrometer acceptable),
percent. PBar = Barometric pressure, in. Hg. T = Ambient
temperature, °F. W = Percent free water by weight, percent. O2 =
Percent oxygen in stack gas, dry basis, percent. 13.0 Method
Performance [Reserved] 14.0 Pollution Prevention [Reserved] 15.0
Waste Management [Reserved] 16.0 Alternative Procedures
16.1 The procedure described in Method 5 for determining
moisture content is an acceptable alternative to Method 4.
16.2 The procedures in Method 6A for determining moisture is an
acceptable alternative to Method 4.
16.3 Method 320 is an acceptable alternative to Method 4 for
determining moisture.
16.4 Using F-factors to determine moisture is an acceptable
alternative to Method 4 for a combustion stack not using a
scrubber, and where a fuel sample is taken during the test run and
analyzed for development of an Fd factor (see Method 19, section
12.3.2), and where stack O2 content is measured by Method 3A or 3B
during each test run. If this option is selected, calculate the
moisture content as follows:
Bws = BH + BA + BF Where: BA = Mole
fraction of moisture in the ambient air. Note:
Values of BA should be between 0.00 and 0.06 with common values
being about 0.015.
BF = Mole fraction of moisture from free water in the fuel.
Note:
Free water in fuel is minimal for distillate oil and gases, such
as propane and natural gas, so this step may be omitted for those
fuels.
BH = Mole fraction of moisture from the hydrogen in the fuel.
Bws =
Mole fraction of moisture in the stack gas. Fd = Volume of dry
combustion components per unit of heat content at 0 percent oxygen,
dscf/10 6 Btu (scm/J). Develop a test specific Fd value using an
integrated fuel sample from each test run and Equation 19-13 in
section 12.3.2 of Method 19. Fw = Volume of wet combustion
components per unit of heat content at 0 percent oxygen, wet scf/10
6 Btu (scm/J). Develop a test specific Fw value using an integrated
fuel sample from each test run and Equation 19-14 in section 12.3.2
of Method 19. %RH = Percent relative humidity (calibrated
hygrometer acceptable), percent. PBar = Barometric pressure, in.
Hg. T = Ambient temperature, °F. W = Percent free water by weight,
percent. O2 = Percent oxygen in stack gas, dry basis, percent. 17.0
References
1. Air Pollution Engineering Manual (Second Edition). Danielson,
J.A. (ed.). U.S. Environmental Protection Agency, Office of Air
Quality Planning and Standards. Research Triangle Park, NC.
Publication No. AP-40. 1973.
2. Devorkin, Howard, et al. Air Pollution Source Testing Manual.
Air Pollution Control District, Los Angeles, CA. November 1963.
3. Methods for Determination of Velocity, Volume, Dust and Mist
Content of Gases. Western Precipitation Division of Joy
Manufacturing Co. Los Angeles, CA. Bulletin WP-50. 1968.
18.0 Tables, Diagrams, Flowcharts, and Validation Data Plant Location
Operator Date Run No. Ambient temperature Barometric pressure Probe
Length
Schematic of Stack Cross section
Traverse Pt.
No.
Sampling time
(Δ), min
Stack
temperature
°C ( °F)
Pressure
differential
across orifice
meter ΔH
mm (in.) H2O
Meter
reading gas
sample
volume
m 3 (ft 3)
ΔVm m
3 (ft 3)
Gas sample
temperature at
dry gas meter
Temperature
of gas
leaving
condenser
or last
impinger
°C ( °F)
Inlet
Tmin
°C ( °F)
Outlet
Tmout
°C ( °F)
Average
Location Test Date Operator Barometric pressure Comments: Figure
4-3. Moisture Determination - Reference Method Method 5 -
Determination of Particulate Matter Emissions From Stationary
Sources Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3.
1.0 Scope and Application
1.1 Analyte. Particulate matter (PM). No CAS number
assigned.
1.2 Applicability. This method is applicable for the
determination of PM emissions from stationary sources.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
Particulate matter is withdrawn isokinetically from the source
and collected on a glass fiber filter maintained at a temperature
of 120 ±14 °C (248 ±25 °F) or such other temperature as specified
by an applicable subpart of the standards or approved by the
Administrator for a particular application. The PM mass, which
includes any material that condenses at or above the filtration
temperature, is determined gravimetrically after the removal of
uncombined water.
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies
6.1 Sample Collection. The following items are required for
sample collection:
6.1.1 Sampling Train. A schematic of the sampling train used in
this method is shown in Figure 5-1 in section 18.0. Complete
construction details are given in APTD-0581 (Reference 2 in section
17.0); commercial models of this train are also available. For
changes from APTD-0581 and for allowable modifications of the train
shown in Figure 5-1, see the following subsections.
Note:
The operating and maintenance procedures for the sampling train
are described in APTD-0576 (Reference 3 in section 17.0). Since
correct usage is important in obtaining valid results, all users
should read APTD-0576 and adopt the operating and maintenance
procedures outlined in it, unless otherwise specified herein.
6.1.1.1 Probe Nozzle. Stainless steel (316) or glass with a
sharp, tapered leading edge. The angle of taper shall be ≤30°, and
the taper shall be on the outside to preserve a constant internal
diameter. The probe nozzle shall be of the button-hook or elbow
design, unless otherwise specified by the Administrator. If made of
stainless steel, the nozzle shall be constructed from seamless
tubing. Other materials of construction may be used, subject to the
approval of the Administrator. A range of nozzle sizes suitable for
isokinetic sampling should be available. Typical nozzle sizes range
from 0.32 to 1.27 cm ( 1/8 to 1/2 in) inside diameter (ID) in
increments of 0.16 cm ( 1/16 in). Larger nozzles sizes are also
available if higher volume sampling trains are used. Each nozzle
shall be calibrated, according to the procedures outlined in
section 10.1.
6.1.1.2 Probe Liner. Borosilicate or quartz glass tubing with a
heating system capable of maintaining a probe gas temperature
during sampling of 120 ±14 °C (248 ±25 °F), or such other
temperature as specified by an applicable subpart of the standards
or as approved by the Administrator for a particular application.
Since the actual temperature at the outlet of the probe is not
usually monitored during sampling, probes constructed according to
APTD-0581 and utilizing the calibration curves of APTD-0576 (or
calibrated according to the procedure outlined in APTD-0576) will
be considered acceptable. Either borosilicate or quartz glass probe
liners may be used for stack temperatures up to about 480 °C (900
°F); quartz glass liners shall be used for temperatures between 480
and 900 °C (900 and 1,650 °F). Both types of liners may be used at
higher temperatures than specified for short periods of time,
subject to the approval of the Administrator. The softening
temperature for borosilicate glass is 820 °C (1500 °F), and for
quartz glass it is 1500 °C (2700 °F). Whenever practical, every
effort should be made to use borosilicate or quartz glass probe
liners. Alternatively, metal liners (e.g., 316 stainless steel,
Incoloy 825 or other corrosion resistant metals) made of seamless
tubing may be used, subject to the approval of the
Administrator.
6.1.1.3 Pitot Tube. Type S, as described in section 6.1 of
Method 2, or other device approved by the Administrator. The pitot
tube shall be attached to the probe (as shown in Figure 5-1) to
allow constant monitoring of the stack gas velocity. The impact
(high pressure) opening plane of the pitot tube shall be even with
or above the nozzle entry plane (see Method 2, Figure 2-7) during
sampling. The Type S pitot tube assembly shall have a known
coefficient, determined as outlined in section 10.0 of Method
2.
6.1.1.4 Differential Pressure Gauge. Inclined manometer or
equivalent device (two), as described in section 6.2 of Method 2.
One manometer shall be used for velocity head (Δp) readings, and
the other, for orifice differential pressure readings.
6.1.1.5 Filter Holder. Borosilicate glass, with a glass or
Teflon frit filter support and a silicone rubber gasket. Other
materials of construction (e.g., stainless steel or Viton) may be
used, subject to the approval of the Administrator. The holder
design shall provide a positive seal against leakage from the
outside or around the filter. The holder shall be attached
immediately at the outlet of the probe (or cyclone, if used).
6.1.1.6 Filter Heating System. Any heating system capable of
monitoring and maintaining temperature around the filter shall be
used to ensure the sample gas temperature exiting the filter of 120
±14 °C (248 ±25 °F) during sampling or such other temperature as
specified by an applicable subpart of the standards or approved by
the Administrator for a particular application. The monitoring and
regulation of the temperature around the filter may be done with
the filter temperature sensor or another temperature sensor.
6.1.1.7 Filter Temperature Sensor. A temperature sensor capable
of measuring temperature to within ±3 °C (5.4 °F) shall be
installed so that the sensing tip of the temperature sensor is in
direct contact with the sample gas exiting the filter. The sensing
tip of the sensor may be encased in glass, Teflon, or metal and
must protrude at least 1/2 in. into the sample gas exiting the
filter. The filter temperature sensor must be monitored and
recorded during sampling to ensure a sample gas temperature exiting
the filter of 120 ±14 °C (248 ±25 °F), or such other temperature as
specified by an applicable subpart of the standards or approved by
the Administrator for a particular application.
6.1.1.8 Condenser. The following system shall be used to
determine the stack gas moisture content: Four impingers connected
in series with leak-free ground glass fittings or any similar
leak-free noncontaminating fittings. The first, third, and fourth
impingers shall be of the Greenburg-Smith design, modified by
replacing the tip with a 1.3 cm ( 1/2 in.) ID glass tube extending
to about 1.3 cm ( 1/2 in.) from the bottom of the flask. The second
impinger shall be of the Greenburg-Smith design with the standard
tip. Modifications (e.g., using flexible connections between
the impingers, using materials other than glass, or using flexible
vacuum lines to connect the filter holder to the condenser) may be
used, subject to the approval of the Administrator. The first and
second impingers shall contain known quantities of water (Section
8.3.1), the third shall be empty, and the fourth shall contain a
known weight of silica gel, or equivalent desiccant. A temperature
sensor, capable of measuring temperature to within 1 °C (2 °F)
shall be placed at the outlet of the fourth impinger for monitoring
purposes. Alternatively, any system that cools the sample gas
stream and allows measurement of the water condensed and moisture
leaving the condenser, each to within 0.5 g may be used, subject to
the approval of the Administrator. An acceptable technique involves
the measurement of condensed water either gravimetrically and the
determination of the moisture leaving the condenser by: (1)
Monitoring the temperature and pressure at the exit of the
condenser and using Dalton's law of partial pressures; or (2)
passing the sample gas stream through a tared silica gel (or
equivalent desiccant) trap with exit gases kept below 20 °C (68 °F)
and determining the weight gain. If means other than silica gel are
used to determine the amount of moisture leaving the condenser, it
is recommended that silica gel (or equivalent) still be used
between the condenser system and pump to prevent moisture
condensation in the pump and metering devices and to avoid the need
to make corrections for moisture in the metered volume.
Note:
If a determination of the PM collected in the impingers is
desired in addition to moisture content, the impinger system
described above shall be used, without modification. Individual
States or control agencies requiring this information shall be
contacted as to the sample recovery and analysis of the impinger
contents.
6.1.1.9 Metering System. Vacuum gauge, leak-free pump,
calibrated temperature sensors, dry gas meter (DGM) capable of
measuring volume to within 2 percent, and related equipment, as
shown in Figure 5-1. Other metering systems capable of maintaining
sampling rates within 10 percent of isokinetic and of determining
sample volumes to within 2 percent may be used, subject to the
approval of the Administrator. When the metering system is used in
conjunction with a pitot tube, the system shall allow periodic
checks of isokinetic rates. The average DGM temperature for use in
the calculations of section 12.0 may be obtained by averaging the
two temperature sensors located at the inlet and outlet of the DGM
as shown in Figure 5-3 or alternatively from a single temperature
sensor located at the immediate outlet of the DGM or the plenum of
the DGM.
6.1.1.10 Sampling trains utilizing metering systems designed for
higher flow rates than that described in APTD-0581 or APTD-0576 may
be used provided that the specifications of this method are
met.
6.1.2 Barometer. Mercury, aneroid, or other barometer capable of
measuring atmospheric pressure to within 2.5 mm Hg (0.1 in.).
Note:
The barometric pressure reading may be obtained from a nearby
National Weather Service station. In this case, the station value
(which is the absolute barometric pressure) shall be requested and
an adjustment for elevation differences between the weather station
and sampling point shall be made at a rate of minus 2.5 mm Hg (0.1
in.) per 30 m (100 ft) elevation increase or plus 2.5 mm Hg (0.1
in) per 30 m (100 ft) elevation decrease.
6.1.3 Gas Density Determination Equipment. Temperature sensor
and pressure gauge, as described in sections 6.3 and 6.4 of Method
2, and gas analyzer, if necessary, as described in Method 3. The
temperature sensor shall, preferably, be permanently attached to
the pitot tube or sampling probe in a fixed configuration, such
that the tip of the sensor extends beyond the leading edge of the
probe sheath and does not touch any metal. Alternatively, the
sensor may be attached just prior to use in the field. Note,
however, that if the temperature sensor is attached in the field,
the sensor must be placed in an interference-free arrangement with
respect to the Type S pitot tube openings (see Method 2, Figure
2-4). As a second alternative, if a difference of not more than 1
percent in the average velocity measurement is to be introduced,
the temperature sensor need not be attached to the probe or pitot
tube. (This alternative is subject to the approval of the
Administrator.)
6.2 Sample Recovery. The following items are required for sample
recovery:
6.2.1 Probe-Liner and Probe-Nozzle Brushes. Nylon bristle
brushes with stainless steel wire handles. The probe brush shall
have extensions (at least as long as the probe) constructed of
stainless steel, Nylon, Teflon, or similarly inert material. The
brushes shall be properly sized and shaped to brush out the probe
liner and nozzle.
6.2.2 Wash Bottles. Two Glass wash bottles are recommended.
Alternatively, polyethylene wash bottles may be used. It is
recommended that acetone not be stored in polyethylene bottles for
longer than a month.
6.2.3 Glass Sample Storage Containers. Chemically resistant,
borosilicate glass bottles, for acetone washes, 500 ml or 1000 ml.
Screw cap liners shall either be rubber-backed Teflon or shall be
constructed so as to be leak-free and resistant to chemical attack
by acetone. (Narrow mouth glass bottles have been found to be less
prone to leakage.) Alternatively, polyethylene bottles may be
used.
6.2.4 Petri dishes. For filter samples; glass, polystyrene, or
polyethylene, unless otherwise specified by the Administrator.
6.2.5 Balance. To measure condensed water to within 0.5 g at a
minimum.
6.2.6 Plastic Storage Containers. Air-tight containers to store
silica gel.
6.2.7 Funnel and Rubber Policeman. To aid in transfer of silica
gel to container; not necessary if silica gel is weighed in the
field.
6.2.8 Funnel. Glass or polyethylene, to aid in sample
recovery.
6.3 Sample Analysis. The following equipment is required for
sample analysis:
6.3.1 Glass Weighing Dishes.
6.3.2 Desiccator.
6.3.3 Analytical Balance. To measure to within 0.1 mg.
6.3.4 Balance. To measure to within 0.5 g.
6.3.5 Beakers. 250 ml.
6.3.6 Hygrometer. To measure the relative humidity of the
laboratory environment.
6.3.7 Temperature Sensor. To measure the temperature of the
laboratory environment.
7.0 Reagents and Standards
7.1 Sample Collection. The following reagents are required for
sample collection:
7.1.1 Filters. Glass fiber filters, without organic binder,
exhibiting at least 99.95 percent efficiency (<0.05 percent
penetration) on 0.3 micron dioctyl phthalate smoke particles. The
filter efficiency test shall be conducted in accordance with ASTM
Method D 2986-71, 78, or 95a (incorporated by reference - see §
60.17). Test data from the supplier's quality control program are
sufficient for this purpose. In sources containing SO2 or SO3, the
filter material must be of a type that is unreactive to SO2 or SO3.
Reference 10 in section 17.0 may be used to select the appropriate
filter.
7.1.2 Silica Gel. Indicating type, 6 to 16 mesh. If previously
used, dry at 175 °C (350 °F) for 2 hours. New silica gel may be
used as received. Alternatively, other types of desiccants
(equivalent or better) may be used, subject to the approval of the
Administrator.
7.1.3 Water. When analysis of the material caught in the
impingers is required, deionized distilled water [to conform to
ASTM D1193-77 or 91 Type 3 (incorporated by reference - see §
60.17)] with at least <0.001 percent residue shall be used or as
specified in the applicable method requiring analysis of the water.
Run reagent blanks prior to field use to eliminate a high blank on
test samples.
7.1.4 Crushed Ice.
7.2 Sample Recovery. Acetone, reagent grade, ≤0.001 percent
residue, in glass bottles, is required. Acetone from metal
containers generally has a high residue blank and should not be
used. Sometimes, suppliers transfer acetone to glass bottles from
metal containers; thus, acetone blanks shall be run prior to field
use and only acetone with low blank values (≤0.001 percent) shall
be used. In no case shall a blank value of greater than 0.001
percent of the weight of acetone used be subtracted from the sample
weight.
7.3 Sample Analysis. The following reagents are required for
sample analysis:
7.3.1 Acetone. Same as in section 7.2.
7.3.2 Desiccant. Anhydrous calcium sulfate, indicating type.
Alternatively, other types of desiccants may be used, subject to
the approval of the Administrator.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Pretest Preparation. It is suggested that sampling equipment
be maintained according to the procedures described in APTD-0576.
Alternative mercury-free thermometers may be used if the
thermometers are at a minimum equivalent in terms of performance or
suitably effective for the specific temperature measurement
application.
8.1.1 Place 200 to 300 g of silica gel in each of several
air-tight containers. Weigh each container, including silica gel,
to the nearest 0.5 g, and record this weight. As an alternative,
the silica gel need not be preweighed, but may be weighed directly
in its impinger or sampling holder just prior to train
assembly.
8.1.2 Check filters visually against light for irregularities,
flaws, or pinhole leaks. Label filters of the proper diameter on
the back side near the edge using numbering machine ink. As an
alternative, label the shipping containers (glass, polystyrene or
polyethylene petri dishes), and keep each filter in its identified
container at all times except during sampling.
8.1.3 Desiccate the filters at 20 ±5.6 °C (68 ±10 °F) and
ambient pressure for at least 24 hours. Weigh each filter (or
filter and shipping container) at intervals of at least 6 hours to
a constant weight (i.e., ≤0.5 mg change from previous
weighing). Record results to the nearest 0.1 mg. During each
weighing, the period for which the filter is exposed to the
laboratory atmosphere shall be less than 2 minutes. Alternatively
(unless otherwise specified by the Administrator), the filters may
be oven dried at 105 °C (220 °F) for 2 to 3 hours, desiccated for 2
hours, and weighed. Procedures other than those described, which
account for relative humidity effects, may be used, subject to the
approval of the Administrator.
8.2 Preliminary Determinations.
8.2.1 Select the sampling site and the minimum number of
sampling points according to Method 1 or as specified by the
Administrator. Determine the stack pressure, temperature, and the
range of velocity heads using Method 2; it is recommended that a
leak check of the pitot lines (see Method 2, section 8.1) be
performed. Determine the moisture content using Approximation
Method 4 or its alternatives for the purpose of making isokinetic
sampling rate settings. Determine the stack gas dry molecular
weight, as described in Method 2, section 8.6; if integrated Method
3 sampling is used for molecular weight determination, the
integrated bag sample shall be taken simultaneously with, and for
the same total length of time as, the particulate sample run.
8.2.2 Select a nozzle size based on the range of velocity heads,
such that it is not necessary to change the nozzle size in order to
maintain isokinetic sampling rates. During the run, do not change
the nozzle size. Ensure that the proper differential pressure gauge
is chosen for the range of velocity heads encountered (see section
8.3 of Method 2).
8.2.3 Select a suitable probe liner and probe length such that
all traverse points can be sampled. For large stacks, consider
sampling from opposite sides of the stack to reduce the required
probe length.
8.2.4 Select a total sampling time greater than or equal to the
minimum total sampling time specified in the test procedures for
the specific industry such that (l) the sampling time per point is
not less than 2 minutes (or some greater time interval as specified
by the Administrator), and (2) the sample volume taken (corrected
to standard conditions) will exceed the required minimum total gas
sample volume. The latter is based on an approximate average
sampling rate.
8.2.5 The sampling time at each point shall be the same. It is
recommended that the number of minutes sampled at each point be an
integer or an integer plus one-half minute, in order to avoid
timekeeping errors.
8.2.6 In some circumstances (e.g., batch cycles) it may
be necessary to sample for shorter times at the traverse points and
to obtain smaller gas sample volumes. In these cases, the
Administrator's approval must first be obtained.
8.3 Preparation of Sampling Train.
8.3.1 During preparation and assembly of the sampling train,
keep all openings where contamination can occur covered until just
prior to assembly or until sampling is about to begin. Place 100 ml
of water in each of the first two impingers, leave the third
impinger empty, and transfer approximately 200 to 300 g of
preweighed silica gel from its container to the fourth impinger.
More silica gel may be used, but care should be taken to ensure
that it is not entrained and carried out from the impinger during
sampling. Place the container in a clean place for later use in the
sample recovery. Alternatively, the weight of the silica gel plus
impinger may be determined to the nearest 0.5 g and recorded.
8.3.2 Using a tweezer or clean disposable surgical gloves, place
a labeled (identified) and weighed filter in the filter holder. Be
sure that the filter is properly centered and the gasket properly
placed so as to prevent the sample gas stream from circumventing
the filter. Check the filter for tears after assembly is
completed.
8.3.3 When glass probe liners are used, install the selected
nozzle using a Viton A O-ring when stack temperatures are less than
260 °C (500 °F) or a heat-resistant string gasket when temperatures
are higher. See APTD-0576 for details. Other connecting systems
using either 316 stainless steel or Teflon ferrules may be used.
When metal liners are used, install the nozzle as discussed above
or by a leak-free direct mechanical connection. Mark the probe with
heat resistant tape or by some other method to denote the proper
distance into the stack or duct for each sampling point.
8.3.4 Set up the train as shown in Figure 5-1 ensuring that the
connections are leak-tight. Subject to the approval of the
Administrator, a glass cyclone may be used between the probe and
filter holder when the total particulate catch is expected to
exceed 100 mg or when water droplets are present in the stack
gas.
8.3.5 Place crushed ice around the impingers.
8.4 Leak-Check Procedures.
8.4.1 Leak Check of Metering System Shown in Figure 5-1. That
portion of the sampling train from the pump to the orifice meter
should be leak-checked prior to initial use and after each
shipment. Leakage after the pump will result in less volume being
recorded than is actually sampled. The following procedure is
suggested (see Figure 5-2): Close the main valve on the meter box.
Insert a one-hole rubber stopper with rubber tubing attached into
the orifice exhaust pipe. Disconnect and vent the low side of the
orifice manometer. Close off the low side orifice tap. Pressurize
the system to 13 to 18 cm (5 to 7 in.) water column by blowing into
the rubber tubing. Pinch off the tubing, and observe the manometer
for one minute. A loss of pressure on the manometer indicates a
leak in the meter box; leaks, if present, must be corrected.
8.4.2 Pretest Leak Check. A pretest leak check of the sampling
train is recommended, but not required. If the pretest leak check
is conducted, the following procedure should be used.
8.4.2.1 After the sampling train has been assembled, turn on and
set the filter and probe heating systems to the desired operating
temperatures. Allow time for the temperatures to stabilize. If a
Viton A O-ring or other leak-free connection is used in assembling
the probe nozzle to the probe liner, leak-check the train at the
sampling site by plugging the nozzle and pulling a 380 mm (15 in.)
Hg vacuum.
Note:
A lower vacuum may be used, provided that it is not exceeded
during the test.
8.4.2.2 If a heat-resistant string is used, do not connect the
probe to the train during the leak check. Instead, leak-check the
train by first plugging the inlet to the filter holder (cyclone, if
applicable) and pulling a 380 mm (15 in.) Hg vacuum (see note in
section 8.4.2.1). Then connect the probe to the train, and
leak-check at approximately 25 mm (1 in.) Hg vacuum; alternatively,
the probe may be leak-checked with the rest of the sampling train,
in one step, at 380 mm (15 in.) Hg vacuum. Leakage rates in excess
of 4 percent of the average sampling rate or 0.00057 m 3/min (0.020
cfm), whichever is less, are unacceptable.
8.4.2.3 The following leak-check instructions for the sampling
train described in APTD-0576 and APTD-0581 may be helpful. Start
the pump with the bypass valve fully open and the coarse adjust
valve completely closed. Partially open the coarse adjust valve,
and slowly close the bypass valve until the desired vacuum is
reached. Do not reverse the direction of the bypass valve, as this
will cause water to back up into the filter holder. If the desired
vacuum is exceeded, either leak-check at this higher vacuum, or end
the leak check and start over.
8.4.2.4 When the leak check is completed, first slowly remove
the plug from the inlet to the probe, filter holder, or cyclone (if
applicable), and immediately turn off the vacuum pump. This
prevents the water in the impingers from being forced backward into
the filter holder and the silica gel from being entrained backward
into the third impinger.
8.4.3 Leak Checks During Sample Run. If, during the sampling
run, a component (e.g., filter assembly or impinger) change
becomes necessary, a leak check shall be conducted immediately
before the change is made. The leak check shall be done according
to the procedure outlined in section 8.4.2 above, except that it
shall be done at a vacuum equal to or greater than the maximum
value recorded up to that point in the test. If the leakage rate is
found to be no greater than 0.00057 m 3/min (0.020 cfm) or 4
percent of the average sampling rate (whichever is less), the
results are acceptable, and no correction will need to be applied
to the total volume of dry gas metered; if, however, a higher
leakage rate is obtained, either record the leakage rate and plan
to correct the sample volume as shown in section 12.3 of this
method, or void the sample run.
Note:
Immediately after component changes, leak checks are optional.
If such leak checks are done, the procedure outlined in section
8.4.2 above should be used.
8.4.4 Post-Test Leak Check. A leak check of the sampling train
is mandatory at the conclusion of each sampling run. The leak check
shall be performed in accordance with the procedures outlined in
section 8.4.2, except that it shall be conducted at a vacuum equal
to or greater than the maximum value reached during the sampling
run. If the leakage rate is found to be no greater than 0.00057 m 3
min (0.020 cfm) or 4 percent of the average sampling rate
(whichever is less), the results are acceptable, and no correction
need be applied to the total volume of dry gas metered. If,
however, a higher leakage rate is obtained, either record the
leakage rate and correct the sample volume as shown in section 12.3
of this method, or void the sampling run.
8.5 Sampling Train Operation. During the sampling run, maintain
an isokinetic sampling rate (within 10 percent of true isokinetic
unless otherwise specified by the Administrator) and a sample gas
temperature through the filter of 120 ±14 °C (248 ±25 °F) or such
other temperature as specified by an applicable subpart of the
standards or approved by the Administrator.
8.5.1 For each run, record the data required on a data sheet
such as the one shown in Figure 5-3. Be sure to record the initial
DGM reading. Record the DGM readings at the beginning and end of
each sampling time increment, when changes in flow rates are made,
before and after each leak check, and when sampling is halted. Take
other readings indicated by Figure 5-3 at least once at each sample
point during each time increment and additional readings when
significant changes (20 percent variation in velocity head
readings) necessitate additional adjustments in flow rate. Level
and zero the manometer. Because the manometer level and zero may
drift due to vibrations and temperature changes, make periodic
checks during the traverse.
8.5.2 Clean the portholes prior to the test run to minimize the
chance of collecting deposited material. To begin sampling, verify
that the filter and probe heating systems are up to temperature,
remove the nozzle cap, verify that the pitot tube and probe are
properly positioned. Position the nozzle at the first traverse
point with the tip pointing directly into the gas stream.
Immediately start the pump, and adjust the flow to isokinetic
conditions. Nomographs are available which aid in the rapid
adjustment of the isokinetic sampling rate without excessive
computations. These nomographs are designed for use when the Type S
pitot tube coefficient (Cp) is 0.85 ±0.02, and the stack gas
equivalent density [dry molecular weight (Md)] is equal to 29 ±4.
APTD-0576 details the procedure for using the nomographs. If Cp and
Md are outside the above stated ranges, do not use the nomographs
unless appropriate steps (see Reference 7 in section 17.0) are
taken to compensate for the deviations.
8.5.3 When the stack is under significant negative pressure
(i.e., height of impinger stem), take care to close the
coarse adjust valve before inserting the probe into the stack to
prevent water from backing into the filter holder. If necessary,
the pump may be turned on with the coarse adjust valve closed.
8.5.4 When the probe is in position, block off the openings
around the probe and porthole to prevent unrepresentative dilution
of the gas stream.
8.5.5 Traverse the stack cross-section, as required by Method 1
or as specified by the Administrator, being careful not to bump the
probe nozzle into the stack walls when sampling near the walls or
when removing or inserting the probe through the portholes; this
minimizes the chance of extracting deposited material.
8.5.6 During the test run, make periodic adjustments to keep the
temperature around the filter holder at the proper level to
maintain the sample gas temperature exiting the filter; add more
ice and, if necessary, salt to maintain a temperature of less than
20 °C (68 °F) at the condenser/silica gel outlet. Also,
periodically check the level and zero of the manometer.
8.5.7 If the pressure drop across the filter becomes too high,
making isokinetic sampling difficult to maintain, the filter may be
replaced in the midst of the sample run. It is recommended that
another complete filter assembly be used rather than attempting to
change the filter itself. Before a new filter assembly is
installed, conduct a leak check (see section 8.4.3). The total PM
weight shall include the summation of the filter assembly
catches.
8.5.8 A single train shall be used for the entire sample run,
except in cases where simultaneous sampling is required in two or
more separate ducts or at two or more different locations within
the same duct, or in cases where equipment failure necessitates a
change of trains. In all other situations, the use of two or more
trains will be subject to the approval of the Administrator.
Note:
When two or more trains are used, separate analyses of the
front-half and (if applicable) impinger catches from each train
shall be performed, unless identical nozzle sizes were used on all
trains, in which case, the front-half catches from the individual
trains may be combined (as may the impinger catches) and one
analysis of front-half catch and one analysis of impinger catch may
be performed. Consult with the Administrator for details concerning
the calculation of results when two or more trains are used.
8.5.9 At the end of the sample run, close the coarse adjust
valve, remove the probe and nozzle from the stack, turn off the
pump, record the final DGM meter reading, and conduct a post-test
leak check, as outlined in section 8.4.4. Also, leak-check the
pitot lines as described in Method 2, section 8.1. The lines must
pass this leak check, in order to validate the velocity head
data.
8.6 Calculation of Percent Isokinetic. Calculate percent
isokinetic (see Calculations, section 12.11) to determine whether
the run was valid or another test run should be made. If there was
difficulty in maintaining isokinetic rates because of source
conditions, consult with the Administrator for possible variance on
the isokinetic rates.
8.7 Sample Recovery.
8.7.1 Proper cleanup procedure begins as soon as the probe is
removed from the stack at the end of the sampling period. Allow the
probe to cool.
8.7.2 When the probe can be safely handled, wipe off all
external PM near the tip of the probe nozzle, and place a cap over
it to prevent losing or gaining PM. Do not cap off the probe tip
tightly while the sampling train is cooling down. This would create
a vacuum in the filter holder, thereby drawing water from the
impingers into the filter holder.
8.7.3 Before moving the sample train to the cleanup site, remove
the probe from the sample train and cap the open outlet of the
probe. Be careful not to lose any condensate that might be present.
Cap the filter inlet where the probe was fastened. Remove the
umbilical cord from the last impinger, and cap the impinger. If a
flexible line is used between the first impinger or condenser and
the filter holder, disconnect the line at the filter holder, and
let any condensed water or liquid drain into the impingers or
condenser. Cap off the filter holder outlet and impinger inlet.
Either ground-glass stoppers, plastic caps, or serum caps may be
used to close these openings.
8.7.4 Transfer the probe and filter-impinger assembly to the
cleanup area. This area should be clean and protected from the wind
so that the chances of contaminating or losing the sample will be
minimized.
8.7.5 Save a portion of the acetone used for cleanup as a blank.
From each storage container of acetone used for cleanup, save 200
ml and place in a glass sample container labeled “acetone blank.”
To minimize any particulate contamination, rinse the wash bottle
prior to filling from the tested container.
8.7.6 Inspect the train prior to and during disassembly, and
note any abnormal conditions. Treat the samples as follows:
8.7.6.1 Container No. 1. Carefully remove the filter from the
filter holder, and place it in its identified petri dish container.
Use a pair of tweezers and/or clean disposable surgical gloves to
handle the filter. If it is necessary to fold the filter, do so
such that the PM cake is inside the fold. Using a dry Nylon bristle
brush and/or a sharp-edged blade, carefully transfer to the petri
dish any PM and/or filter fibers that adhere to the filter holder
gasket. Seal the container.
8.7.6.2 Container No. 2. Taking care to see that dust on the
outside of the probe or other exterior surfaces does not get into
the sample, quantitatively recover PM or any condensate from the
probe nozzle, probe fitting, probe liner, and front half of the
filter holder by washing these components with acetone and placing
the wash in a glass container. Deionized distilled water may be
used instead of acetone when approved by the Administrator and
shall be used when specified by the Administrator. In these cases,
save a water blank, and follow the Administrator's directions on
analysis. Perform the acetone rinse as follows:
8.7.6.2.1 Carefully remove the probe nozzle. Clean the inside
surface by rinsing with acetone from a wash bottle and brushing
with a Nylon bristle brush. Brush until the acetone rinse shows no
visible particles, after which make a final rinse of the inside
surface with acetone.
8.7.6.2.2 Brush and rinse the inside parts of the fitting with
acetone in a similar way until no visible particles remain.
8.7.6.2.3 Rinse the probe liner with acetone by tilting and
rotating the probe while squirting acetone into its upper end so
that all inside surfaces will be wetted with acetone. Let the
acetone drain from the lower end into the sample container. A
funnel (glass or polyethylene) may be used to aid in transferring
liquid washes to the container. Follow the acetone rinse with a
probe brush. Hold the probe in an inclined position, squirt acetone
into the upper end as the probe brush is being pushed with a
twisting action through the probe; hold a sample container
underneath the lower end of the probe, and catch any acetone and
particulate matter that is brushed from the probe. Run the brush
through the probe three times or more until no visible PM is
carried out with the acetone or until none remains in the probe
liner on visual inspection. With stainless steel or other metal
probes, run the brush through in the above prescribed manner at
least six times since metal probes have small crevices in which
particulate matter can be entrapped. Rinse the brush with acetone,
and quantitatively collect these washings in the sample container.
After the brushing, make a final acetone rinse of the probe.
8.7.6.2.4 It is recommended that two people clean the probe to
minimize sample losses. Between sampling runs, keep brushes clean
and protected from contamination.
8.7.6.2.5 Clean the inside of the front half of the filter
holder by rubbing the surfaces with a Nylon bristle brush and
rinsing with acetone. Rinse each surface three times or more if
needed to remove visible particulate. Make a final rinse of the
brush and filter holder. Carefully rinse out the glass cyclone,
also (if applicable). After all acetone washings and particulate
matter have been collected in the sample container, tighten the lid
on the sample container so that acetone will not leak out when it
is shipped to the laboratory. Mark the height of the fluid level to
allow determination of whether leakage occurred during transport.
Label the container to clearly identify its contents.
8.7.6.3 Container No. 3. Note the color of the indicating silica
gel to determine whether it has been completely spent, and make a
notation of its condition. Transfer the silica gel from the fourth
impinger to its original container, and seal. A funnel may make it
easier to pour the silica gel without spilling. A rubber policeman
may be used as an aid in removing the silica gel from the impinger.
It is not necessary to remove the small amount of dust particles
that may adhere to the impinger wall and are difficult to remove.
Since the gain in weight is to be used for moisture calculations,
do not use any water or other liquids to transfer the silica gel.
If a balance is available in the field, follow the procedure for
Container No. 3 in section 11.2.3.
8.7.6.4 Impinger Water. Treat the impingers as follows: Make a
notation of any color or film in the liquid catch. Measure the
liquid that is in the first three impingers by weighing it to
within 0.5 g at a minimum by using a balance. Record the weight of
liquid present. This information is required to calculate the
moisture content of the effluent gas. Discard the liquid after
measuring and recording the weight, unless analysis of the impinger
catch is required (see Note, section 6.1.1.8). If a
different type of condenser is used, measure the amount of moisture
condensed gravimetrically.
8.8 Sample Transport. Whenever possible, containers should be
shipped in such a way that they remain upright at all times.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
8.4,
10.1-10.6
Sampling equipment leak check
and calibration
Ensures accurate measurement
of stack gas flow rate, sample volume.
9.2 Volume Metering System Checks. The following procedures are
suggested to check the volume metering system calibration values at
the field test site prior to sample collection. These procedures
are optional.
9.2.1 Meter Orifice Check. Using the calibration data obtained
during the calibration procedure described in section 10.3,
determine the ΔH@ for the metering system orifice. The ΔH@ is the
orifice pressure differential in units of in. H2O that correlates
to 0.75 cfm of air at 528 °R and 29.92 in. Hg. The ΔH@ is
calculated as follows:
Where: ΔH = Average pressure differential
across the orifice meter, in. H2O. Tm = Absolute average DGM
temperature, °R. Pbar = Barometric pressure, in. Hg. θ = Total
sampling time, min. Y = DGM calibration factor, dimensionless. Vm =
Volume of gas sample as measured by DGM, dcf. 0.0319 = (0.0567 in.
Hg/°R) (0.75 cfm) 2
9.2.1.1 Before beginning the field test (a set of three runs
usually constitutes a field test), operate the metering system
(i.e., pump, volume meter, and orifice) at the ΔH@ pressure
differential for 10 minutes. Record the volume collected, the DGM
temperature, and the barometric pressure. Calculate a DGM
calibration check value, Yc, as follows:
where: Yc = DGM calibration check value,
dimensionless. 10 = Run time, min.
9.2.1.2 Compare the Yc value with the dry gas meter calibration
factor Y to determine that: 0.97Y <Yc <1.03Y. If the Yc value
is not within this range, the volume metering system should be
investigated before beginning the test.
9.2.2 Calibrated Critical Orifice. A critical orifice,
calibrated against a wet test meter or spirometer and designed to
be inserted at the inlet of the sampling meter box, may be used as
a check by following the procedure of section 16.2.
10.0 Calibration and Standardization Note:
Maintain a laboratory log of all calibrations.
10.1 Probe Nozzle. Probe nozzles shall be calibrated before
their initial use in the field. Using a micrometer, measure the ID
of the nozzle to the nearest 0.025 mm (0.001 in.). Make three
separate measurements using different diameters each time, and
obtain the average of the measurements. The difference between the
high and low numbers shall not exceed 0.1 mm (0.004 in.). When
nozzles become nicked, dented, or corroded, they shall be reshaped,
sharpened, and recalibrated before use. Each nozzle shall be
permanently and uniquely identified.
10.2 Pitot Tube Assembly. The Type S pitot tube assembly shall
be calibrated according to the procedure outlined in section 10.1
of Method 2.
10.3 Metering System.
10.3.1 Calibration Prior to Use. Before its initial use in the
field, the metering system shall be calibrated as follows: Connect
the metering system inlet to the outlet of a wet test meter that is
accurate to within 1 percent. Refer to Figure 5-4. The wet test
meter should have a capacity of 30 liters/rev (1 ft 3/rev). A
spirometer of 400 liters (14 ft 3) or more capacity, or equivalent,
may be used for this calibration, although a wet test meter is
usually more practical. The wet test meter should be periodically
calibrated with a spirometer or a liquid displacement meter to
ensure the accuracy of the wet test meter. Spirometers or wet test
meters of other sizes may be used, provided that the specified
accuracies of the procedure are maintained. Run the metering system
pump for about 15 minutes with the orifice manometer indicating a
median reading as expected in field use to allow the pump to warm
up and to permit the interior surface of the wet test meter to be
thoroughly wetted. Then, at each of a minimum of three orifice
manometer settings, pass an exact quantity of gas through the wet
test meter and note the gas volume indicated by the DGM. Also note
the barometric pressure and the temperatures of the wet test meter,
the inlet of the DGM, and the outlet of the DGM. Select the highest
and lowest orifice settings to bracket the expected field operating
range of the orifice. Use a minimum volume of 0.14 m 3 (5 ft 3) at
all orifice settings. Record all the data on a form similar to
Figure 5-5 and calculate Y, the DGM calibration factor, and ΔH ,
the orifice calibration factor, at each orifice setting as shown on
Figure 5-5. Allowable tolerances for individual Y and ΔH values are
given in Figure 5-5. Use the average of the Y values in the
calculations in section 12.0.
10.3.1.1 Before calibrating the metering system, it is suggested
that a leak check be conducted. For metering systems having
diaphragm pumps, the normal leak-check procedure will not detect
leakages within the pump. For these cases the following leak-check
procedure is suggested: make a 10-minute calibration run at 0.00057
m 3/min (0.020 cfm). At the end of the run, take the difference of
the measured wet test meter and DGM volumes. Divide the difference
by 10 to get the leak rate. The leak rate should not exceed 0.00057
m 3/min (0.020 cfm).
10.3.2 Calibration After Use. After each field use, the
calibration of the metering system shall be checked by performing
three calibration runs at a single, intermediate orifice setting
(based on the previous field test), with the vacuum set at the
maximum value reached during the test series. To adjust the vacuum,
insert a valve between the wet test meter and the inlet of the
metering system. Calculate the average value of the DGM calibration
factor. If the value has changed by more than 5 percent,
recalibrate the meter over the full range of orifice settings, as
detailed in section 10.3.1.
Note:
Alternative procedures (e.g., rechecking the orifice
meter coefficient) may be used, subject to the approval of the
Administrator.
10.3.3 Acceptable Variation in Calibration Check. If the DGM
coefficient values obtained before and after a test series differ
by more than 5 percent, the test series shall either be voided, or
calculations for the test series shall be performed using whichever
meter coefficient value (i.e., before or after) gives the
lower value of total sample volume.
10.4 Probe Heater Calibration. Use a heat source to generate air
heated to selected temperatures that approximate those expected to
occur in the sources to be sampled. Pass this air through the probe
at a typical sample flow rate while measuring the probe inlet and
outlet temperatures at various probe heater settings. For each air
temperature generated, construct a graph of probe heating system
setting versus probe outlet temperature. The procedure outlined in
APTD-0576 can also be used. Probes constructed according to
APTD-0581 need not be calibrated if the calibration curves in
APTD-0576 are used. Also, probes with outlet temperature monitoring
capabilities do not require calibration.
Note:
The probe heating system shall be calibrated before its initial
use in the field.
10.5 Temperature Sensors. Use the procedure in Section 10.3 of
Method 2 to calibrate in-stack temperature sensors. Dial
thermometers, such as are used for the DGM and condenser outlet,
shall be calibrated against mercury-in-glass thermometers. An
alternative mercury-free NIST-traceable thermometer may be used if
the thermometer is, at a minimum, equivalent in terms of
performance or suitably effective for the specific temperature
measurement application. As an alternative, the following
single-point calibration procedure may be used. After each test run
series, check the accuracy (and, hence, the calibration) of each
thermocouple system at ambient temperature, or any other
temperature, within the range specified by the manufacturer, using
a reference thermometer (either ASTM reference thermometer or a
thermometer that has been calibrated against an ASTM reference
thermometer). The temperatures of the thermocouple and reference
thermometers shall agree to within ±2 °F.
10.6 Barometer. Calibrate against a mercury barometer or
NIST-traceable barometer prior to the field test. Alternatively,
barometric pressure may be obtained from a weather report that has
been adjusted for the test point (on the stack) elevation.
10.7 Field Balance Calibration Check. Check the calibration of
the balance used to weigh impingers with a weight that is at least
500g or within 50g of a loaded impinger. The weight must be ASTM
E617-13 “Standard Specification for Laboratory Weights and
Precision Mass Standards” (incorporated by reference - see 40 CFR
60.17) Class 6 (or better). Daily before use, the field balance
must measure the weight within ±0.5g of the certified mass. If the
daily balance calibration check fails, perform corrective measures
and repeat the check before using balance.
10.8 Analytical Balance Calibration. Perform a multipoint
calibration (at least five points spanning the operational range)
of the analytical balance before the first use, and semiannually
thereafter. The calibration of the analytical balance must be
conducted using ASTM E617-13 “Standard Specification for Laboratory
Weights and Precision Mass Standards” (incorporated by reference -
see 40 CFR 60.17) Class 2 (or better) tolerance weights. Audit the
balance each day it is used for gravimetric measurements by
weighing at least one ASTM E617-13 Class 2 tolerance (or better)
calibration weight that corresponds to 50 to 150 percent of the
weight of one filter or between 1g and 5g. If the scale cannot
reproduce the value of the calibration weight to within 0.5 mg of
the certified mass, perform corrective measures, and conduct the
multipoint calibration before use.
11.0 Analytical Procedure
11.1 Record the data required on a sheet such as the one shown
in Figure 5-6.
11.2 Handle each sample container as follows:
11.2.1 Container No. 1. Leave the contents in the shipping
container or transfer the filter and any loose PM from the sample
container to a tared weighing container. Desiccate for 24 hours in
a desiccator containing anhydrous calcium sulfate. Weigh to a
constant weight, and report the results to the nearest 0.1 mg. For
the purposes of this section, the term “constant weight” means a
difference of no more than 0.5 mg or 1 percent of total weight less
tare weight, whichever is greater, between two consecutive
weighings, with no less than 6 hours of desiccation time between
weighings. Alternatively, the sample may be oven dried at 104 °C
(220 °F) for 2 to 3 hours, cooled in the desiccator, and weighed to
a constant weight, unless otherwise specified by the Administrator.
The sample may be oven dried at 104 °C (220 °F) for 2 to 3 hours.
Once the sample has cooled, weigh the sample, and use this weight
as a final weight.
11.2.2 Container No. 2. Note the level of liquid in the
container, and confirm on the analysis sheet whether leakage
occurred during transport. If a noticeable amount of leakage has
occurred, either void the sample or use methods, subject to the
approval of the Administrator, to correct the final results.
Measure the liquid in this container either volumetrically to ±1 ml
or gravimetrically to ±0.5 g. Transfer the contents to a tared 250
ml beaker, and evaporate to dryness at ambient temperature and
pressure. Desiccate for 24 hours, and weigh to a constant weight.
Report the results to the nearest 0.1 mg.
11.2.3 Container No. 3. Weigh the spent silica gel (or silica
gel plus impinger) to the nearest 0.5 g using a balance. This step
may be conducted in the field.
11.2.4 Acetone Blank Container. Measure the acetone in this
container either volumetrically or gravimetrically. Transfer the
acetone to a tared 250 ml beaker, and evaporate to dryness at
ambient temperature and pressure. Desiccate for 24 hours, and weigh
to a constant weight. Report the results to the nearest 0.1 mg.
Note:
The contents of Container No. 2 as well as the acetone blank
container may be evaporated at temperatures higher than ambient. If
evaporation is done at an elevated temperature, the temperature
must be below the boiling point of the solvent; also, to prevent
“bumping,” the evaporation process must be closely supervised, and
the contents of the beaker must be swirled occasionally to maintain
an even temperature. Use extreme care, as acetone is highly
flammable and has a low flash point.
12.0 Data Analysis and Calculations
Carry out calculations, retaining at least one extra significant
figure beyond that of the acquired data. Round off figures after
the final calculation. Other forms of the equations may be used,
provided that they give equivalent results.
12.1 Nomenclature.
An = Cross-sectional area of nozzle, m 2 (ft 2).
Bws = Water vapor in the gas stream, proportion by volume.
Ca = Acetone blank residue concentration, mg/mg.
cs = Concentration of particulate matter in stack gas, dry
basis, corrected to standard conditions, g/dscm (gr/dscf).
I = Percent of isokinetic sampling.
L1 = Individual leakage rate observed during the leak-check
conducted prior to the first component change, m 3/min (ft
3/min)
La = Maximum acceptable leakage rate for either a pretest
leak-check or for a leak-check following a component change; equal
to 0.00057 m 3/min (0.020 cfm) or 4 percent of the average sampling
rate, whichever is less.
Li = Individual leakage rate observed during the leak-check
conducted prior to the “i th” component change (i = 1, 2, 3 . . .
n), m 3/min (cfm).
Lp = Leakage rate observed during the post-test leak-check, m
3/min (cfm).
ma = Mass of residue of acetone after evaporation, mg.
mn = Total amount of particulate matter collected, mg.
Mw = Molecular weight of water, 18.015 g/g-mole (18.015
lb/lb-mole).
Pbar = Barometric pressure at the sampling site, mm Hg (in.
Hg).
Ps = Absolute stack gas pressure, mm Hg (in. Hg).
Pstd = Standard absolute pressure, 760 mm Hg (29.92 in. Hg).
R = Ideal gas constant, 0.06236 ((mm Hg)(m 3))/((K)(g-mole))
{21.85 ((in. Hg) (ft 3))/((°R) (lb-mole))}.
Tm = Absolute average DGM temperature (see Figure 5-3), K
(°R).
Ts = Absolute average stack gas temperature (see Figure 5-3), K
(°R).
Tstd = Standard absolute temperature, 293.15 K (527.67 °R).
Va = Volume of acetone blank, ml.
Vaw = Volume of acetone used in wash, ml.
V1c = Total volume of liquid collected in impingers and silica
gel (see Figure 5-6), g.
Vm = Volume of gas sample as measured by dry gas meter, dcm
(dcf).
Vm(std) = Volume of gas sample measured by the dry gas meter,
corrected to standard conditions, dscm (dscf).
Vw(std) = Volume of water vapor in the gas sample, corrected to
standard conditions, scm (scf).
Vs = Stack gas velocity, calculated by Method 2, Equation 2-7,
using data obtained from Method 5, m/sec (ft/sec).
Wa = Weight of residue in acetone wash, mg.
Y = Dry gas meter calibration factor.
ΔH = Average pressure differential across the orifice meter (see
Figure 5-4), mm H2O (in. H2O).
ρa = Density of acetone, mg/ml (see label on bottle).
θ = Total sampling time, min.
θ1 = Sampling time interval, from the beginning of a run until
the first component change, min.
θi = Sampling time interval, between two successive component
changes, beginning with the interval between the first and second
changes, min.
θp = Sampling time interval, from the final (nth) component
change until the end of the sampling run, min.
13.6 = Specific gravity of mercury.
60 = Sec/min.
100 = Conversion to percent.
12.2 Average Dry Gas Meter Temperature and Average Orifice
Pressure Drop. See data sheet (Figure 5-3).
12.3
K1 = 0.38572 °K/mm Hg for metric units, = 17.636 °R/in. Hg for
English units.
12.4 Volume of Water Vapor Condensed
Where: K2
= 0.001335 m 3/g for metric units, = 0.04716 ft 3/g for English
units.
12.5 Moisture Content.
Note:
In saturated or water droplet-laden gas streams, two
calculations of the moisture content of the stack gas shall be
made, one from the impinger analysis (Equation 5-3), and a second
from the assumption of saturated conditions. The lower of the two
values of Bws shall be considered correct. The procedure for
determining the moisture content based upon the assumption of
saturated conditions is given in section 4.0 of Method 4. For the
purposes of this method, the average stack gas temperature from
Figure 5-3 may be used to make this determination, provided that
the accuracy of the in-stack temperature sensor is ±1 °C (2
°F).
12.6 Acetone Blank Concentration.
12.7 Acetone Wash Blank.
12.8 Total Particulate Weight. Determine the total particulate
matter catch from the sum of the weights obtained from Containers 1
and 2 less the acetone blank (see Figure 5-6).
Note:
In no case shall a blank value of greater than 0.001 percent of
the weight of acetone used be subtracted from the sample weight.
Refer to section 8.5.8 to assist in calculation of results
involving two or more filter assemblies or two or more sampling
trains.
12.9 Particulate Concentration.
Where: K3 = 0.001 g/mg for metric units. =
0.0154 gr/mg for English units.
12.10 Conversion Factors:
From
To
Multiply by
ft
3
m 3
0.02832
gr
mg
64.80004
gr/ft
3
mg/m 3
2288.4
mg
g
0.001
gr
lb
1.429 × 10−4
12.11 Isokinetic Variation.
12.11.1
Where: K4 = 0.003456 ((mm Hg)(m 3))/((ml)(°K)) for metric units, =
0.002668 ((in. Hg)(ft 3))/((ml)(°R)) for English units.
12.11.2
Where: K5 = 4.3209 for metric units, = 0.09450 for English units.
12.11.3 Acceptable Results. If 90 percent ≤I ≤110 percent, the
results are acceptable. If the PM results are low in comparison to
the standard, and “I” is over 110 percent or less than 90 percent,
the Administrator may opt to accept the results. Reference 4 in
section 17.0 may be used to make acceptability judgments. If “I” is
judged to be unacceptable, reject the results, and repeat the
sampling run.
12.12 Stack Gas Velocity and Volumetric Flow Rate. Calculate the
average stack gas velocity and volumetric flow rate, if needed,
using data obtained in this method and the equations in sections
12.3 and 12.4 of Method 2.
16.1 Dry Gas Meter as a Calibration Standard. A DGM may be used
as a calibration standard for volume measurements in place of the
wet test meter specified in section 10.3, provided that it is
calibrated initially and recalibrated periodically as follows:
16.1.1 Standard Dry Gas Meter Calibration.
16.1.1.1. The DGM to be calibrated and used as a secondary
reference meter should be of high quality and have an appropriately
sized capacity (e.g., 3 liters/rev (0.1 ft 3/rev)). A
spirometer (400 liters (14 ft 3) or more capacity), or equivalent,
may be used for this calibration, although a wet test meter is
usually more practical. The wet test meter should have a capacity
of 30 liters/rev (1 ft 3/rev) and capable of measuring volume to
within 1.0 percent. Wet test meters should be checked against a
spirometer or a liquid displacement meter to ensure the accuracy of
the wet test meter. Spirometers or wet test meters of other sizes
may be used, provided that the specified accuracies of the
procedure are maintained.
16.1.1.2 Set up the components as shown in Figure 5-7. A
spirometer, or equivalent, may be used in place of the wet test
meter in the system. Run the pump for at least 5 minutes at a flow
rate of about 10 liters/min (0.35 cfm) to condition the interior
surface of the wet test meter. The pressure drop indicated by the
manometer at the inlet side of the DGM should be minimized (no
greater than 100 mm H2O (4 in. H2O) at a flow rate of 30 liters/min
(1 cfm)). This can be accomplished by using large diameter tubing
connections and straight pipe fittings.
16.1.1.3 Collect the data as shown in the example data sheet
(see Figure 5-8). Make triplicate runs at each of the flow rates
and at no less than five different flow rates. The range of flow
rates should be between 10 and 34 liters/min (0.35 and 1.2 cfm) or
over the expected operating range.
16.1.1.4
Where: K1 = 0.38572 °K/mm Hg for metric units, = 17.636 °R/in. Hg
for English units. Tadj = 273.15 °C for metric units = 459.67 °F
for English units.
16.1.1.5 Compare the three Yds values at each of the flow rates
and determine the maximum and minimum values. The difference
between the maximum and minimum values at each flow rate should be
no greater than 0.030. Extra sets of triplicate runs may be made in
order to complete this requirement. In addition, the meter
coefficients should be between 0.95 and 1.05. If these
specifications cannot be met in three sets of successive triplicate
runs, the meter is not suitable as a calibration standard and
should not be used as such. If these specifications are met,
average the three Yds values at each flow rate resulting in no less
than five average meter coefficients, Yds.
16.1.1.6 Prepare a curve of meter coefficient, Yds, versus flow
rate, Q, for the DGM. This curve shall be used as a reference when
the meter is used to calibrate other DGMs and to determine whether
recalibration is required.
16.1.2 Standard Dry Gas Meter Recalibration.
16.1.2.1 Recalibrate the standard DGM against a wet test meter
or spirometer annually or after every 200 hours of operation,
whichever comes first. This requirement is valid provided the
standard DGM is kept in a laboratory and, if transported, cared for
as any other laboratory instrument. Abuse to the standard meter may
cause a change in the calibration and will require more frequent
recalibrations.
16.1.2.2 As an alternative to full recalibration, a two-point
calibration check may be made. Follow the same procedure and
equipment arrangement as for a full recalibration, but run the
meter at only two flow rates [suggested rates are 14 and 30
liters/min (0.5 and 1.0 cfm)]. Calculate the meter coefficients for
these two points, and compare the values with the meter calibration
curve. If the two coefficients are within 1.5 percent of the
calibration curve values at the same flow rates, the meter need not
be recalibrated until the next date for a recalibration check.
16.2 Critical Orifices As Calibration Standards. Critical
orifices may be used as calibration standards in place of the wet
test meter specified in section 16.1, provided that they are
selected, calibrated, and used as follows:
16.2.1 Selection of Critical Orifices.
16.2.1.1 The procedure that follows describes the use of
hypodermic needles or stainless steel needle tubings which have
been found suitable for use as critical orifices. Other materials
and critical orifice designs may be used provided the orifices act
as true critical orifices (i.e., a critical vacuum can be
obtained, as described in section 16.2.2.2.3). Select five critical
orifices that are appropriately sized to cover the range of flow
rates between 10 and 34 liters/min (0.35 and 1.2 cfm) or the
expected operating range. Two of the critical orifices should
bracket the expected operating range. A minimum of three critical
orifices will be needed to calibrate a Method 5 DGM; the other two
critical orifices can serve as spares and provide better selection
for bracketing the range of operating flow rates. The needle sizes
and tubing lengths shown in Table 5-1 in section 18.0 give the
approximate flow rates.
16.2.1.2 These needles can be adapted to a Method 5 type
sampling train as follows: Insert a serum bottle stopper, 13 by 20
mm sleeve type, into a 1/2-inch Swagelok (or equivalent) quick
connect. Insert the needle into the stopper as shown in Figure
5-9.
16.2.2 Critical Orifice Calibration. The procedure described in
this section uses the Method 5 meter box configuration with a DGM
as described in section 6.1.1.9 to calibrate the critical orifices.
Other schemes may be used, subject to the approval of the
Administrator.
16.2.2.1 Calibration of Meter Box. The critical orifices must be
calibrated in the same configuration as they will be used
(i.e., there should be no connections to the inlet of the
orifice).
16.2.2.1.1 Before calibrating the meter box, leak check the
system as follows: Fully open the coarse adjust valve, and
completely close the by-pass valve. Plug the inlet. Then turn on
the pump, and determine whether there is any leakage. The leakage
rate shall be zero (i.e., no detectable movement of the DGM
dial shall be seen for 1 minute).
16.2.2.1.2 Check also for leakages in that portion of the
sampling train between the pump and the orifice meter. See section
8.4.1 for the procedure; make any corrections, if necessary. If
leakage is detected, check for cracked gaskets, loose fittings,
worn O-rings, etc., and make the necessary repairs.
16.2.2.1.3 After determining that the meter box is leakless,
calibrate the meter box according to the procedure given in section
10.3. Make sure that the wet test meter meets the requirements
stated in section 16.1.1.1. Check the water level in the wet test
meter. Record the DGM calibration factor, Y.
16.2.2.2 Calibration of Critical Orifices. Set up the apparatus
as shown in Figure 5-10.
16.2.2.2.1 Allow a warm-up time of 15 minutes. This step is
important to equilibrate the temperature conditions through the
DGM.
16.2.2.2.2 Leak check the system as in section 16.2.2.1.1. The
leakage rate shall be zero.
16.2.2.2.3 Before calibrating the critical orifice, determine
its suitability and the appropriate operating vacuum as follows:
Turn on the pump, fully open the coarse adjust valve, and adjust
the by-pass valve to give a vacuum reading corresponding to about
half of atmospheric pressure. Observe the meter box orifice
manometer reading, ΔH. Slowly increase the vacuum reading until a
stable reading is obtained on the meter box orifice manometer.
Record the critical vacuum for each orifice. Orifices that do not
reach a critical value shall not be used.
16.2.2.2.4 Obtain the barometric pressure using a barometer as
described in section 6.1.2. Record the barometric pressure, Pbar,
in mm Hg (in. Hg).
16.2.2.2.5 Conduct duplicate runs at a vacuum of 25 to 50 mm Hg
(1 to 2 in. Hg) above the critical vacuum. The runs shall be at
least 5 minutes each. The DGM volume readings shall be in
increments of complete revolutions of the DGM. As a guideline, the
times should not differ by more than 3.0 seconds (this includes
allowance for changes in the DGM temperatures) to achieve ±0.5
percent in K′ (see Eq. 5-11). Record the information listed in
Figure 5-11.
Calculate the arithmetic mean of the K′ values. The individual
K' values should not differ by more than ±0.5 percent from the mean
value.
16.2.3 Using the Critical Orifices as Calibration Standards.
16.2.3.1 Record the barometric pressure.
16.2.3.2 Calibrate the metering system according to the
procedure outlined in section 16.2.2. Record the information listed
in Figure 5-12.
16.2.3.3
Where: K1 = 0.38572 °K/mm Hg for metric units, = 17.636 °R/in. Hg
for English units.
16.2.3.4 Average the DGM calibration values for each of the flow
rates. The calibration factor, Y, at each of the flow rates should
not differ by more than ±2 percent from the average.
16.2.3.5 To determine the need for recalibrating the critical
orifices, compare the DGM Y factors obtained from two adjacent
orifices each time a DGM is calibrated; for example, when checking
orifice 13/2.5, use orifices 12/10.2 and 13/5.1. If any critical
orifice yields a DGM Y factor differing by more than 2 percent from
the others, recalibrate the critical orifice according to section
16.2.2.
16.3 Alternative Post-Test Metering System Calibration. The
following procedure may be used as an alternative to the post-test
calibration described in Section 10.3.2. This alternative procedure
does not detect leakages between the inlet of the metering system
and the dry gas meter. Therefore, two steps must be included to
make it an equivalent alternative:
(1) The metering system must pass the post-test leak-check from
either the inlet of the sampling train or the inlet of the metering
system. Therefore, if the train fails the former leak-check,
another leak-check from the inlet of the metering system must be
conducted;
(2) The metering system must pass the leak-check of that portion
of the train from the pump to the orifice meter as described in
Section 8.4.1.
16.3.1 After each test run, do the following:
16.3.1.1 Ensure that the metering system has passed the
post-test leak-check. If not, conduct a leak-check of the metering
system from its inlet.
16.3.1.2 Conduct the leak-check of that portion of the train
from the pump to the orifice meter as described in Section
10.3.1.1.
16.3.1.3 Calculate Yqa for each test run using the following
equation:
Where:
Yqa = Dry gas meter calibration check value, dimensionless. 0.0319
= (29.92/528) (0.75) 2 (in. Hg/°R) cfm 2. ΔH@ = Orifice meter
calibration coefficient, in. H2O. Md = Dry molecular weight of
stack gas, lb/lb-mole. 29 = Dry molecular weight of air,
lb/lb-mole.
16.3.2 After each test run series, do the following:
16.3.2.1 Average the three or more Yqa's obtained from the test
run series and compare this average Yqa with the dry gas meter
calibration factor Y. The average Yqa must be within 5 percent of
Y.
16.3.2.2 If the average Yqa does not meet the 5 percent
criterion, recalibrate the meter over the full range of orifice
settings as detailed in Section 10.3.1. Then follow the procedure
in Section 10.3.3.
17.0 References.
1. Addendum to Specifications for Incinerator Testing at Federal
Facilities. PHS, NCAPC. December 6, 1967.
2. Martin, Robert M. Construction Details of Isokinetic
Source-Sampling Equipment. Environmental Protection Agency.
Research Triangle Park, NC. APTD-0581. April 1971.
3. Rom, Jerome J. Maintenance, Calibration, and Operation of
Isokinetic Source Sampling Equipment. Environmental Protection
Agency. Research Triangle Park, NC. APTD-0576. March 1972.
4. Smith, W.S., R.T. Shigehara, and W.F. Todd. A Method of
Interpreting Stack Sampling Data. Paper Presented at the 63rd
Annual Meeting of the Air Pollution Control Association, St. Louis,
MO. June 14-19, 1970.
5. Smith, W.S., et al. Stack Gas Sampling Improved and
Simplified With New Equipment. APCA Paper No. 67-119. 1967.
6. Specifications for Incinerator Testing at Federal Facilities.
PHS, NCAPC. 1967.
7. Shigehara, R.T. Adjustment in the EPA Nomograph for Different
Pitot Tube Coefficients and Dry Molecular Weights. Stack Sampling
News 2:4-11. October 1974.
8. Vollaro, R.F. A Survey of Commercially Available
Instrumentation for the Measurement of Low-Range Gas Velocities.
U.S. Environmental Protection Agency, Emission Measurement Branch.
Research Triangle Park, NC. November 1976 (unpublished paper).
9. Annual Book of ASTM Standards. Part 26. Gaseous Fuels; Coal
and Coke; Atmospheric Analysis. American Society for Testing and
Materials. Philadelphia, PA. 1974. pp. 617-622.
10. Felix, L.G., G.I. Clinard, G.E. Lacy, and J.D. McCain.
Inertial Cascade Impactor Substrate Media for Flue Gas Sampling.
U.S. Environmental Protection Agency. Research Triangle Park, NC
27711. Publication No. EPA-600/7-77-060. June 1977. 83 pp.
11. Westlin, P.R. and R.T. Shigehara. Procedure for Calibrating
and Using Dry Gas Volume Meters as Calibration Standards. Source
Evaluation Society Newsletter. 3(1):17-30. February
1978.
12. Lodge, J.P., Jr., J.B. Pate, B.E. Ammons, and G.A. Swanson.
The Use of Hypodermic Needles as Critical Orifices in Air Sampling.
J. Air Pollution Control Association. 16:197-200. 1966.
13. Shigehara, Roger T., P.G. Royals, and E.W. Steward.
“Alternative Method 5 Post-Test Calibration.” Entropy Incorporated,
Research Triangle Park, NC 27709.
18.0 Tables, Diagrams, Flowcharts, and Validation Data
Table 5-1 Flor Rates for Various needle
Sizes and Tube Lengths
Gauge/cm
Flow rate
liters/min.
Gauge/cm
Flow rate
liters/min.
12/7.6
32.56
14/2.5
19.54
12/10.2
30.02
14/5.1
17.27
13/2.5
25.77
14/7.6
16.14
13/5.1
23.50
15/3.2
14.16
13/7.6
22.37
15/7.6
11.61
13/10.2
20.67
15/10.2
10.48
Date Train ID DGM
cal. factor Critical orifice ID
Dry gas
meter
Run No.
1
2
Final reading
m 3 (ft
3)
Initial
reading
m 3 (ft
3)
Difference, V
m
m 3 (ft
3)
Inlet/Outlet
Temperatures:
°C ( °F)
/
/
Initial
°C ( °F)
/
/
Final
min/sec
/
/
Av.
Temeperature, t m
min
Time, θ
Orifice man. rdg.,
ΔH
mm (in.) H 2
Bar. pressure, P
bar
mm (in.) Hg
Ambient
temperature, tamb
mm (in.) Hg
Pump vacuum
K′ factor
Average
Figure 5-11. Data sheet of determining K′ factor. Date Train ID
Critical orifice ID Critical orifice K' factor
Dry gas
meter
Run No.
1
2
Final reading
m 3 (ft
3)
Initial
reading
m 3 (ft
3)
Difference,
Vm
m 3 (ft
3)
Inlet/outlet
temperatures
°C ( °F)
/
/
Initial
°C ( °F)
/
/
Final
°C ( °F)
Avg.
Temperature, tm
min/sec
/
/
Time, θ
min
Orifice man. rdg.,
ΔH
min
Bar. pressure,
Pbar
mm (in.) H2O
Ambient
temperature, tamb
mm (in.) Hg
Pump vacuum
°C ( °F)
Vm(std)
mm (in.) Hg
Vcr(std)
m 3 (ft
3)
DGM cal. factor,
Y
m 3 (ft
3)
Figure 5-12. Data Sheet for Determining DGM Y Factor Method 5A -
Determination of Particulate Matter Emissions From the Asphalt
Processing and Asphalt Roofing Industry Note:
This method does not include all of the specifications (e.g.,
equipment and supplies) and procedures (e.g., sampling and
analytical) essential to its performance. Some material is
incorporated by reference from other methods in this part.
Therefore, to obtain reliable results, persons using this method
should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, and Method
5.
1.0 Scope and Applications
1.1 Analyte. Particulate matter (PM). No CAS number
assigned.
1.2 Applicability. This method is applicable for the
determination of PM emissions from asphalt roofing industry process
saturators, blowing stills, and other sources as specified in the
regulations.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
Particulate matter is withdrawn isokinetically from the source
and collected on a glass fiber filter maintained at a temperature
of 42 ±10 °C (108 ±18 °F). The PM mass, which includes any material
that condenses at or above the filtration temperature, is
determined gravimetrically after the removal of uncombined
water.
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies
6.1 Sample Collection. Same as Method 5, section 6.1, with the
following exceptions and additions:
6.1.1 Probe Liner. Same as Method 5, section 6.1.1.2, with the
note that at high stack gas temperatures greater than 250 °C (480
°F), water-cooled probes may be required to control the probe exit
temperature to 42 ±10 °C (108 ±18 °F).
6.1.2 Precollector Cyclone. Borosilicate glass following the
construction details shown in Air Pollution Technical Document
(APTD)-0581, “Construction Details of Isokinetic Source-Sampling
Equipment” (Reference 2 in Method 5, section 17.0).
Note:
The cyclone shall be used when the stack gas moisture is greater
than 10 percent, and shall not be used otherwise.
6.1.3 Filter Heating System. Any heating (or cooling) system
capable of maintaining a sample gas temperature at the exit end of
the filter holder during sampling at 42 ±10 °C (108 ±18 °F).
6.2 Sample Recovery. The following items are required for sample
recovery:
6.2.1 Probe-Liner and Probe-Nozzle Brushes, Graduated Cylinder
and/or Balance, Plastic Storage Containers, and Funnel and Rubber
Policeman. Same as in Method 5, sections 6.2.1, 6.2.5, 6.2.6, and
6.2.7, respectively.
6.2.2 Wash Bottles. Glass.
6.2.3 Sample Storage Containers. Chemically resistant 500-ml or
1,000-ml borosilicate glass bottles, with rubber-backed Teflon
screw cap liners or caps that are constructed so as to be
leak-free, and resistant to chemical attack by
1,1,1-trichloroethane (TCE). (Narrow-mouth glass bottles have been
found to be less prone to leakage.)
6.2.4 Petri Dishes. Glass, unless otherwise specified by the
Administrator.
6.2.5 Funnel. Glass.
6.3 Sample Analysis. Same as Method 5, section 6.3, with the
following additions:
6.3.1 Beakers. Glass, 250-ml and 500-ml.
6.3.2 Separatory Funnel. 100-ml or greater.
7.0. Reagents and Standards
7.1 Sample Collection. The following reagents are required for
sample collection:
7.1.1 Filters, Silica Gel, Water, and Crushed Ice. Same as in
Method 5, sections 7.1.1, 7.1.2, 7.1.3, and 7.1.4,
respectively.
7.1.2 Stopcock Grease. TCE-insoluble, heat-stable grease (if
needed). This is not necessary if screw-on connectors with Teflon
sleeves, or similar, are used.
7.2 Sample Recovery. Reagent grade TCE, ≤0.001 percent residue
and stored in glass bottles. Run TCE blanks before field use, and
use only TCE with low blank values (≤0.001 percent). In no case
shall a blank value of greater than 0.001 percent of the weight of
TCE used be subtracted from the sample weight.
7.3 Analysis. Two reagents are required for the analysis:
7.3.1 TCE. Same as in section 7.2.
7.3.2 Desiccant. Same as in Method 5, section 7.3.2.
8.0. Sample Collection, Preservation, Storage, and Transport
8.1 Pretest Preparation. Unless otherwise specified, maintain
and calibrate all components according to the procedure described
in APTD-0576, “Maintenance, Calibration, and Operation of
Isokinetic Source-Sampling Equipment” (Reference 3 in Method 5,
Section 17.0). Alternative mercury-free thermometers may be used if
the thermometers are, at a minimum, equivalent in terms of
performance or suitably effective for the specific temperature
measurement application.
8.1.1 Prepare probe liners and sampling nozzles as needed for
use. Thoroughly clean each component with soap and water followed
by a minimum of three TCE rinses. Use the probe and nozzle brushes
during at least one of the TCE rinses (refer to section 8.7 for
rinsing techniques). Cap or seal the open ends of the probe liners
and nozzles to prevent contamination during shipping.
8.1.2 Prepare silica gel portions and glass filters as specified
in Method 5, section 8.1.
8.2 Preliminary Determinations. Select the sampling site, probe
nozzle, and probe length as specified in Method 5, section 8.2.
Select a total sampling time greater than or equal to the minimum
total sampling time specified in the “Test Methods and Procedures”
section of the applicable subpart of the regulations. Follow the
guidelines outlined in Method 5, section 8.2 for sampling time per
point and total sample volume collected.
8.3 Preparation of Sampling Train. Prepare the sampling train as
specified in Method 5, section 8.3, with the addition of the
precollector cyclone, if used, between the probe and filter holder.
The temperature of the precollector cyclone, if used, should be
maintained in the same range as that of the filter, i.e., 42
±10 °C (108 ±18 °F). Use no stopcock grease on ground glass joints
unless grease is insoluble in TCE.
8.4 Leak-Check Procedures. Same as Method 5, section 8.4.
8.5 Sampling Train Operation. Operate the sampling train as
described in Method 5, section 8.5, except maintain the temperature
of the gas exiting the filter holder at 42 ±10 °C (108 ±18 °F).
8.6 Calculation of Percent Isokinetic. Same as Method 5, section
8.6.
8.7 Sample Recovery. Same as Method 5, section 8.7.1 through
8.7.6.1, with the addition of the following:
8.7.1 Container No. 2 (Probe to Filter Holder).
8.7.1.1 Taking care to see that material on the outside of the
probe or other exterior surfaces does not get into the sample,
quantitatively recover PM or any condensate from the probe nozzle,
probe fitting, probe liner, precollector cyclone and collector
flask (if used), and front half of the filter holder by washing
these components with TCE and placing the wash in a glass
container. Carefully measure the total amount of TCE used in the
rinses. Perform the TCE rinses as described in Method 5, section
8.7.6.2, using TCE instead of acetone.
8.7.1.2 Brush and rinse the inside of the cyclone, cyclone
collection flask, and the front half of the filter holder. Brush
and rinse each surface three times or more, if necessary, to remove
visible PM.
8.7.2 Container No. 3 (Silica Gel). Same as in Method 5, section
8.7.6.3.
8.7.3 Impinger Water. Same as Method 5, section 8.7.6.4.
8.8 Blank. Save a portion of the TCE used for cleanup as a
blank. Take 200 ml of this TCE directly from the wash bottle being
used, and place it in a glass sample container labeled “TCE
Blank.”
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
8.4, 10.0
Sampling equipment leak check
and calibration
Ensures accurate measurement
of stack gas flow rate, sample volume.
9.2 A quality control (QC) check of the volume metering system
at the field site is suggested before collecting the sample. Use
the procedure outlined in Method 5, section 9.2.
10.0 Calibration and Standardization
Same as Method 5, section 10.0.
11.0 Analytical Procedures
11.1 Analysis. Record the data required on a sheet such as the
one shown in Figure 5A-1. Handle each sample container as
follows:
11.1.1 Container No. 1 (Filter). Transfer the filter from the
sample container to a tared glass weighing dish, and desiccate for
24 hours in a desiccator containing anhydrous calcium sulfate.
Rinse Container No. 1 with a measured amount of TCE, and analyze
this rinse with the contents of Container No. 2. Weigh the filter
to a constant weight. For the purpose of this analysis, the term
“constant weight” means a difference of no more than 10 percent of
the net filter weight or 2 mg (whichever is greater) between two
consecutive weighings made 24 hours apart. Report the “final
weight” to the nearest 0.1 mg as the average of these two
values.
11.1.2 Container No. 2 (Probe to Filter Holder).
11.1.2.1 Before adding the rinse from Container No. 1 to
Container No. 2, note the level of liquid in Container No. 2, and
confirm on the analysis sheet whether leakage occurred during
transport. If noticeable leakage occurred, either void the sample
or take steps, subject to the approval of the Administrator, to
correct the final results.
11.1.2.2 Add the rinse from Container No. 1 to Container No. 2
and measure the liquid in this container either volumetrically to
±1 ml or gravimetrically to ±0.5 g. Check to see whether there is
any appreciable quantity of condensed water present in the TCE
rinse (look for a boundary layer or phase separation). If the
volume of condensed water appears larger than 5 ml, separate the
oil-TCE fraction from the water fraction using a separatory funnel.
Measure the volume of the water phase to the nearest ml; adjust the
stack gas moisture content, if necessary (see sections 12.3 and
12.4). Next, extract the water phase with several 25-ml portions of
TCE until, by visual observation, the TCE does not remove any
additional organic material. Transfer the remaining water fraction
to a tared beaker and evaporate to dryness at 93 °C (200 °F),
desiccate for 24 hours, and weigh to the nearest 0.1 mg.
11.1.2.3 Treat the total TCE fraction (including TCE from the
filter container rinse and water phase extractions) as follows:
Transfer the TCE and oil to a tared beaker, and evaporate at
ambient temperature and pressure. The evaporation of TCE from the
solution may take several days. Do not desiccate the sample until
the solution reaches an apparent constant volume or until the odor
of TCE is not detected. When it appears that the TCE has
evaporated, desiccate the sample, and weigh it at 24-hour intervals
to obtain a “constant weight” (as defined for Container No. 1
above). The “total weight” for Container No. 2 is the sum of the
evaporated PM weight of the TCE-oil and water phase fractions.
Report the results to the nearest 0.1 mg.
11.1.3 Container No. 3 (Silica Gel). This step may be conducted
in the field. Weigh the spent silica gel (or silica gel plus
impinger) to the nearest 0.5 g using a balance.
11.1.4 “TCE Blank” Container. Measure TCE in this container
either volumetrically or gravimetrically. Transfer the TCE to a
tared 250-ml beaker, and evaporate to dryness at ambient
temperature and pressure. Desiccate for 24 hours, and weigh to a
constant weight. Report the results to the nearest 0.1 mg.
Note:
In order to facilitate the evaporation of TCE liquid samples,
these samples may be dried in a controlled temperature oven at
temperatures up to 38 °C (100 °F) until the liquid is
evaporated.
12.0 Data Analysis and Calculations
Carry out calculations, retaining at least one extra significant
figure beyond that of the acquired data. Round off figures after
the final calculation. Other forms of the equations may be used as
long as they give equivalent results.
12.1 Nomenclature. Same as Method 5, section 12.1, with the
following additions:
Ct = TCE blank residue concentration, mg/g. mt = Mass of residue of
TCE blank after evaporation, mg. Vpc = Volume of water collected in
precollector, ml. Vt = Volume of TCE blank, ml. Vtw = Volume of TCE
used in wash, ml. Wt = Weight of residue in TCE wash, mg. ρt =
Density of TCE (see label on bottle), g/ml.
12.2 Dry Gas Meter Temperature, Orifice Pressure Drop, and Dry
Gas Volume. Same as Method 5, sections 12.2 and 12.3, except use
data obtained in performing this test.
12.3 Volume of Water Vapor.
Where: K2 = 0.001333 m 3/ml for metric units. =
0.04706 ft 3/ml for English units.
12.4 Moisture Content.
Note:
In saturated or water droplet-laden gas streams, two
calculations of the moisture content of the stack gas shall be
made, one from the impinger and precollector analysis (Equations
5A-1 and 5A-2) and a second from the assumption of saturated
conditions. The lower of the two values of moisture content shall
be considered correct. The procedure for determining the moisture
content based upon assumption of saturated conditions is given in
section 4.0 of Method 4. For the purpose of this method, the
average stack gas temperature from Figure 5-3 of Method 5 may be
used to make this determination, provided that the accuracy of the
in-stack temperature sensor is within 1 °C (2 °F).
12.5 TCE Blank Concentration.
Note:
In no case shall a blank value of greater than 0.001 percent of
the weight of TCE used be subtracted from the sample weight.
12.6 TCE Wash Blank.
12.7 Total PM Weight. Determine the total PM catch from the sum
of the weights obtained from Containers 1 and 2, less the TCE
blank.
12.8 PM Concentration.
Where: K3 = 0.001 g/mg for metric units =
0.0154 gr/mg for English units
12.9 Isokinetic Variation. Same as in Method 5, section
12.11.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Plant Date
Run No. Filter No. Amount liquid lost during transport Acetone
blank volume, m1 Acetone blank concentration, mg/mg (Equation 5-4)
Acetone wash blank, mg (Equation 5-5)
Container
number
Weight of
particulate collected, mg
Final weight
Tare weight
Weight gain
1.
2.
Total:
Less acetone
blank
Weight of
particulate matter
Volume of liquid
water collected
Impinger volume,
ml
Silica gel weight,
g
Final
Initial
Liquid
collected
Total volume
collected
g* ml
* Convert weight of water to volume by
dividing total weight increase by density of water (1 g/ml).
Method 5B - Determination of Nonsulfuric Acid
Particulate Matter Emissions From Stationary Sources Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, Method
5.
1.0 Scope and Application
1.1 Analyte. Nonsulfuric acid particulate matter. No CAS number
assigned.
1.2 Applicability. This method is determining applicable for the
determination of nonsulfuric acid particulate matter from
stationary sources, only where specified by an applicable subpart
of the regulations or where approved by the Administrator for a
particular application.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
Particulate matter is withdrawn isokinetically from the source
and collected on a glass fiber filter maintained at a temperature
of 160 ±14 °C (320 ±25 °F). The collected sample is then heated in
an oven at 160 °C (320 °F) for 6 hours to volatilize any condensed
sulfuric acid that may have been collected, and the nonsulfuric
acid particulate mass is determined gravimetrically.
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies
Same as Method 5, section 6.0, with the following addition and
exceptions:
6.1 Sample Collection. The probe liner heating system and filter
heating system must be capable of maintaining a sample gas
temperature of 160 ±14 °C (320 ±25 °F).
6.2 Sample Preparation. An oven is required for drying the
sample.
7.0 Reagents and Standards
Same as Method 5, section 7.0.
8.0 Sample Collection, Preservation, Storage, and Transport.
Same as Method 5, with the exception of the following:
8.1 Initial Filter Tare. Oven dry the filter at 160 ±5 °C (320
±10 °F) for 2 to 3 hours, cool in a desiccator for 2 hours, and
weigh. Desiccate to constant weight to obtain the initial tare
weight. Use the applicable specifications and techniques of section
8.1.3 of Method 5 for this determination.
8.2 Probe and Filter Temperatures. Maintain the probe outlet and
filter temperatures at 160 ±14 °C (320 ±25 °F).
9.0 Quality Control
Same as Method 5, section 9.0.
10.0 Calibration and Standardization
Same as Method 5, section 10.0.
11.0 Analytical Procedure
11.1 Record and report the data required on a sheet such as the
one shown in Figure 5B-1.
11.2 Handle each sample container as follows:
11.2.1 Container No. 1. Leave the contents in the shipping
container or transfer the filter and any loose PM from the sample
container to a tared non-reactive oven-proof container. Oven dry
the filter sample at a temperature of 160 ±5 °C (320 ±9 °F) for 6
hours. Cool in a desiccator for 2 hours, and weigh to constant
weight. Report the results to the nearest 0.1 mg. For the purposes
of this section, the term “constant weight” means a difference of
no more than 0.5 mg or 1 percent of total weight less tare weight,
whichever is greater, between two consecutive weighings, with no
less than 6 hours of desiccation time between weighings.
11.2.2 Container No. 2. Note the level of liquid in the
container, and confirm on the analysis sheet whether leakage
occurred during transport. If a noticeable amount of leakage has
occurred, either void the sample or use methods, subject to the
approval of the Administrator, to correct the final results.
Measure the liquid in this container either volumetrically to ±1 ml
or gravimetrically to ±0.5 g. Transfer the contents to a tared 250
ml beaker, and evaporate to dryness at ambient temperature and
pressure. Then oven dry the probe sample at a temperature of 160 ±5
°C (320 ±9 °F) for 6 hours. Cool in a desiccator for 2 hours, and
weigh to constant weight. Report the results to the nearest 0.1
mg.
11.2.3 Container No. 3. Weigh the spent silica gel (or silica
gel plus impinger) to the nearest 0.5 g using a balance. This step
may be conducted in the field.
11.2.4 Acetone Blank Container. Measure the acetone in this
container either volumetrically or gravimetrically. Transfer the
acetone to a tared 250 ml beaker, and evaporate to dryness at
ambient temperature and pressure. Desiccate for 24 hours, and weigh
to a constant weight. Report the results to the nearest 0.1 mg.
Note: The contents of Container No. 2 as well as the acetone
blank container may be evaporated at temperatures higher than
ambient. If evaporation is done at an elevated temperature, the
temperature must be below the boiling point of the solvent; also,
to prevent “bumping,” the evaporation process must be closely
supervised, and the contents of the beaker must be swirled
occasionally to maintain an even temperature. Use extreme care, as
acetone is highly flammable and has a low flash point.
17.0 Tables, Diagrams, Flowcharts, and Validation Data
Container
number
Weight of
particulate collected, mg
Final weight
Tare weight
Weight gain
1.
2.
Total:
Less acetone
blank
Weight of
particulate matter
Volume of liquid
water collected
Impinger volume,
Silica gel weight,
ml
g
Final
Initial
Liquid
collected
Total volume
collected
g* ml
* Convert weight of water to volume by
dividing total weight increase by density of water (1 g/ml).
Figure 5B-1. Analytical Data Sheet Method 5C [Reserved] Method 5D -
Determination of Particulate Matter Emissions from Positive
Pressure Fabric Filters Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, Method 5,
Method 17.
1.0 Scope and Application
1.1 Analyte. Particulate matter (PM). No CAS number
assigned.
1.2 Applicability.
1.2.1 This method is applicable for the determination of PM
emissions from positive pressure fabric filters. Emissions are
determined in terms of concentration (mg/m 3 or gr/ft 3) and
emission rate (kg/hr or lb/hr).
1.2.2 The General Provisions of 40 CFR part 60, § 60.8(e),
require that the owner or operator of an affected facility shall
provide performance testing facilities. Such performance testing
facilities include sampling ports, safe sampling platforms, safe
access to sampling sites, and utilities for testing. It is intended
that affected facilities also provide sampling locations that meet
the specification for adequate stack length and minimal flow
disturbances as described in Method 1. Provisions for testing are
often overlooked factors in designing fabric filters or are
extremely costly. The purpose of this procedure is to identify
appropriate alternative locations and procedures for sampling the
emissions from positive pressure fabric filters. The requirements
that the affected facility owner or operator provide adequate
access to performance testing facilities remain in effect.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 Particulate matter is withdrawn isokinetically from the
source and collected on a glass fiber filter maintained at a
temperature at or above the exhaust gas temperature up to a nominal
120 °C (248 ±25 °F). The particulate mass, which includes any
material that condenses at or above the filtration temperature, is
determined gravimetrically after the removal of uncombined
water.
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user to establish appropriate safety and
health practices and to determine the applicability of regulatory
limitations prior to performing this test method.
6.0 Equipment and Supplies
Same as section 6.0 of either Method 5 or Method 17.
7.0 Reagents and Standards
Same as section 7.0 of either Method 5 or Method 17.
8.0 Sample Collection, Preservation, Storage, and Transport
Same section 8.0 of either Method 5 or Method 17, except replace
section 8.2.1 of Method 5 with the following:
8.1 Determination of Measurement Site. The configuration of
positive pressure fabric filter structures frequently are not
amenable to emission testing according to the requirements of
Method 1. Following are several alternatives for determining
measurement sites for positive pressure fabric filters.
8.1.1 Stacks Meeting Method 1 Criteria. Use a measurement site
as specified in Method 1, section 11.1.
8.1.2 Short Stacks Not Meeting Method 1 Criteria. Use stack
extensions and the procedures in Method 1. Alternatively, use flow
straightening vanes of the “egg-crate” type (see Figure 5D-1).
Locate the measurement site downstream of the straightening vanes
at a distance equal to or greater than two times the average
equivalent diameter of the vane openings and at least one-half of
the overall stack diameter upstream of the stack outlet.
8.1.3 Roof Monitor or Monovent. (See Figure 5D-2). For a
positive pressure fabric filter equipped with a peaked roof
monitor, ridge vent, or other type of monovent, use a measurement
site at the base of the monovent. Examples of such locations are
shown in Figure 5D-2. The measurement site must be upstream of any
exhaust point (e.g., louvered vent).
8.1.4 Compartment Housing. Sample immediately downstream of the
filter bags directly above the tops of the bags as shown in the
examples in Figure 5D-2. Depending on the housing design, use
sampling ports in the housing walls or locate the sampling
equipment within the compartment housing.
8.2 Determination of Number and Location of Traverse Points.
Locate the traverse points according to Method 1, section 11.3.
Because a performance test consists of at least three test runs and
because of the varied configurations of positive pressure fabric
filters, there are several schemes by which the number of traverse
points can be determined and the three test runs can be
conducted.
8.2.1 Single Stacks Meeting Method 1 Criteria. Select the number
of traverse points according to Method 1. Sample all traverse
points for each test run.
8.2.2 Other Single Measurement Sites. For a roof monitor or
monovent, single compartment housing, or other stack not meeting
Method 1 criteria, use at least 24 traverse points. For example,
for a rectangular measurement site, such as a monovent, use a
balanced 5 × 5 traverse point matrix. Sample all traverse points
for each test run.
8.2.3 Multiple Measurement Sites. Sampling from two or more
stacks or measurement sites may be combined for a test run,
provided the following guidelines are met:
8.2.3.1 All measurement sites up to 12 must be sampled. For more
than 12 measurement sites, conduct sampling on at least 12 sites or
50 percent of the sites, whichever is greater. The measurement
sites sampled should be evenly, or nearly evenly, distributed among
the available sites; if not, all sites are to be sampled.
8.2.3.2 The same number of measurement sites must be sampled for
each test run.
8.2.3.3 The minimum number of traverse points per test run is
24. An exception to the 24-point minimum would be a test combining
the sampling from two stacks meeting Method 1 criteria for
acceptable stack length, and Method 1 specifies fewer than 12
points per site.
8.2.3.4 As long as the 24 traverse points per test run criterion
is met, the number of traverse points per measurement site may be
reduced to eight.
8.2.3.5 Alternatively, conduct a test run for each measurement
site individually using the criteria in section 8.2.1 or 8.2.2 to
determine the number of traverse points. Each test run shall count
toward the total of three required for a performance test. If more
than three measurement sites are sampled, the number of traverse
points per measurement site may be reduced to eight as long as at
least 72 traverse points are sampled for all the tests.
8.2.3.6 The following examples demonstrate the procedures for
sampling multiple measurement sites.
8.2.3.6.1 Example 1: A source with nine circular measurement
sites of equal areas may be tested as follows: For each test run,
traverse three measurement sites using four points per diameter
(eight points per measurement site). In this manner, test run
number 1 will include sampling from sites 1,2, and 3; run 2 will
include samples from sites 4, 5, and 6; and run 3 will include
sites 7, 8, and 9. Each test area may consist of a separate test of
each measurement site using eight points. Use the results from all
nine tests in determining the emission average.
8.2.3.6.2 Example 2: A source with 30 rectangular measurement
sites of equal areas may be tested as follows: For each of the
three test runs, traverse five measurement sites using a 3 × 3
matrix of traverse points for each site. In order to distribute the
sampling evenly over all the available measurement sites while
sampling only 50 percent of the sites, number the sites
consecutively from 1 to 30 and sample all the even numbered (or odd
numbered) sites. Alternatively, conduct a separate test of each of
15 measurement sites using section 8.2.1 or 8.2.2 to determine the
number and location of traverse points, as appropriate.
8.2.3.6.3 Example 3: A source with two measurement sites of
equal areas may be tested as follows: For each test of three test
runs, traverse both measurement sites, using section 8.2.3 in
determining the number of traverse points. Alternatively, conduct
two full emission test runs for each measurement site using the
criteria in section 8.2.1 or 8.2.2 to determine the number of
traverse points.
8.2.3.7 Other test schemes, such as random determination of
traverse points for a large number of measurement sites, may be
used with prior approval from the Administrator.
8.3 Velocity Determination.
8.3.1 The velocities of exhaust gases from positive pressure
baghouses are often too low to measure accurately with the type S
pitot tube specified in Method 2 (i.e., velocity head
<1.3 mm H2O (0.05 in. H2O)). For these conditions, measure the
gas flow rate at the fabric filter inlet following the procedures
outlined in Method 2. Calculate the average gas velocity at the
measurement site as shown in section 12.2 and use this average
velocity in determining and maintaining isokinetic sampling
rates.
8.3.2 Velocity determinations to determine and maintain
isokinetic rates at measurement sites with gas velocities within
the range measurable with the type S pitot tube (i.e.,
velocity head greater than 1.3 mm H2O (0.05 in. H2O)) shall be
conducted according to the procedures outlined in Method 2.
8.4 Sampling. Follow the procedures specified in sections 8.1
through 8.6 of Method 5 or sections 8.1 through 8.25 in Method 17
with the exceptions as noted above.
8.5 Sample Recovery. Follow the procedures specified in section
8.7 of Method 5 or section 8.2 of Method 17.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
8.0, 10.0
Sampling equipment leak check
and calibration
Ensures accurate measurement
of stack gas flow rate, sample volume.
9.2 Volume Metering System Checks. Same as Method 5, section
9.2.
10.0 Calibration and Standardization
Same as section 10.0 of either Method 5 or Method 17.
11.0 Analytical Procedure
Same as section 11.0 of either Method 5 or Method 17.
12.0 Data Analysis and Calculations
Same as section 12.0 of either Method 5 or Method 17 with the
following exceptions:
12.1 Nomenclature.
Ao = Measurement site(s) total cross-sectional area, m 2 (ft 2). C
or Cavg = Average concentration of PM for all n runs, mg/scm
(gr/scf). Qi = Inlet gas volume flow rate, m 3/sec (ft 3/sec). mi =
Mass collected for run i of n, mg (gr). To = Average temperature of
gas at measurement site, °K (°R). Ti = Average temperature of gas
at inlet, °K (°R). Voli = Sample volume collected for run i of n,
scm (scf). v = Average gas velocity at the measurement site(s), m/s
(ft/s) Qo = Total baghouse exhaust volumetric flow rate, m 3/sec
(ft 3/sec). Qd = Dilution air flow rate, m 3/sec (ft 3/sec). Tamb =
Ambient Temperature, (°K).
12.2 Average Gas Velocity. When following section 8.3.1,
calculate the average gas velocity at the measurement site as
follows:
12.3 Volumetric Flow Rate. Total volumetric flow rate may be
determined as follows:
12.4 Dilution Air Flow Rate.
12.5 Average PM Concentration. For multiple measurement sites,
calculate the average PM concentration as follows:
17.0 Tables, Diagrams, Flowcharts, and Validation Data
Method 5E - Determination
of Particulate Matter Emissions From the Wool Fiberglass Insulation
Manufacturing Industry Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, and Method
5.
1.0 Scope and Applications
1.1 Analyte. Particulate matter (PM). No CAS number
assigned.
1.2 Applicability. This method is applicable for the
determination of PM emissions from wool fiberglass insulation
manufacturing sources.
2.0 Summary of Method
Particulate matter is withdrawn isokinetically from the source
and is collected either on a glass fiber filter maintained at a
temperature in the range of 120 ±14 °C (248 ±25 °F) and in
impingers in solutions of 0.1 N sodium hydroxide (NaOH). The
filtered particulate mass, which includes any material that
condenses at or above the filtration temperature, is determined
gravimetrically after the removal of uncombined water. The
condensed PM collected in the impinger solutions is determined as
total organic carbon (TOC) using a nondispersive infrared type of
analyzer. The sum of the filtered PM mass and the condensed PM is
reported as the total PM mass.
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Corrosive Reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water at least 15 minutes. Remove clothing
under shower and decontaminate. Treat residual chemical burn as
thermal burn.
5.2.1 Hydrochloric Acid (HCl). Highly toxic. Vapors are highly
irritating to eyes, skin, nose, and lungs, causing severe damage.
May cause bronchitis, pneumonia, or edema of lungs. Exposure to
concentrations of 0.13 to 0.2 percent in air can be lethal in
minutes. Will react with metals, producing hydrogen.
5.2.2 Sodium Hydroxide (NaOH). Causes severe damage to eye
tissues and to skin. Inhalation causes irritation to nose, throat,
and lungs. Reacts exothermically with limited amounts of water.
6.0 Equipment and Supplies
6.1 Sample Collection. Same as Method 5, section 6.1, with the
exception of the following:
6.1.1 Probe Liner. Same as described in section 6.1.1.2 of
Method 5 except use only borosilicate or quartz glass liners.
6.1.2 Filter Holder. Same as described in section 6.1.1.5 of
Method 5 with the addition of a leak-tight connection in the rear
half of the filter holder designed for insertion of a temperature
sensor used for measuring the sample gas exit temperature.
6.2 Sample Recovery. Same as Method 5, section 6.2, except three
wash bottles are needed instead of two and only glass storage
bottles and funnels may be used.
6.3 Sample Analysis. Same as Method 5, section 6.3, with the
additional equipment for TOC analysis as described below:
6.3.1 Sample Blender or Homogenizer. Waring type or
ultrasonic.
6.3.2 Magnetic Stirrer.
6.3.3 Hypodermic Syringe. 0- to 100-µl capacity.
6.3.4 Total Organic Carbon Analyzer. Rosemount Model 2100A
analyzer or equivalent and a recorder.
6.3.5 Beaker. 30-ml.
6.3.6 Water Bath. Temperature controlled.
6.3.7 Volumetric Flasks. 1000-ml and 500-ml.
7.0 Reagents and Standards
Unless otherwise indicated, it is intended that all reagents
conform to the specifications established by the Committee on
Analytical Reagents of the American Chemical Society, where such
specifications are available; otherwise, use the best available
grade.
7.1 Sample Collection. Same as Method 5, section 7.1, with the
addition of 0.1 N NaOH (Dissolve 4 g of NaOH in water and dilute to
1 liter).
7.2 Sample Recovery. Same as Method 5, section 7.2, with the
addition of the following:
7.2.1 Water. Deionized distilled to conform to ASTM
Specification D 1193-77 or 91 Type 3 (incorporated by reference -
see § 60.17). The potassium permanganate (KMnO4) test for
oxidizable organic matter may be omitted when high concentrations
of organic matter are not expected to be present.
7.2.2 Sodium Hydroxide. Same as described in section 7.1.
7.3 Sample Analysis. Same as Method 5, section 7.3, with the
addition of the following:
7.3.1 Carbon Dioxide-Free Water. Distilled or deionized water
that has been freshly boiled for 15 minutes and cooled to room
temperature while preventing exposure to ambient air by using a
cover vented with an Ascarite tube.
7.3.2 Hydrochloric Acid. HCl, concentrated, with a dropper.
7.3.3 Organic Carbon Stock Solution. Dissolve 2.1254 g of dried
potassium biphthalate (HOOCC6H4COOK) in CO2-free water, and dilute
to 1 liter in a volumetric flask. This solution contains 1000 mg/L
organic carbon.
7.3.4 Inorganic Carbon Stock Solution. Dissolve 4.404 g
anhydrous sodium carbonate (Na2CO3.) in about 500 ml of CO2-free
water in a 1-liter volumetric flask. Add 3.497 g anhydrous sodium
bicarbonate (NaHCO3) to the flask, and dilute to 1 liter with CO2
-free water. This solution contains 1000 mg/L inorganic carbon.
7.3.5 Oxygen Gas. CO2 -free.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Pretest Preparation and Preliminary Determinations. Same as
Method 5, sections 8.1 and 8.2, respectively.
8.2 Preparation of Sampling Train. Same as Method 5, section
8.3, except that 0.1 N NaOH is used in place of water in the
impingers. The volumes of the solutions are the same as in Method
5.
8.3 Leak-Check Procedures, Sampling Train Operation, Calculation
of Percent Isokinetic. Same as Method 5, sections 8.4 through 8.6,
respectively.
8.4 Sample Recovery. Same as Method 5, sections 8.7.1 through
8.7.4, with the addition of the following:
8.4.1 Save portions of the water, acetone, and 0.1 N NaOH used
for cleanup as blanks. Take 200 ml of each liquid directly from the
wash bottles being used, and place in glass sample containers
labeled “water blank,” “acetone blank,” and “NaOH blank,”
respectively.
8.4.2 Inspect the train prior to and during disassembly, and
note any abnormal conditions. Treat the samples as follows:
8.4.2.1 Container No. 1. Same as Method 5, section 8.7.6.1.
8.4.2.2 Container No. 2. Use water to rinse the sample nozzle,
probe, and front half of the filter holder three times in the
manner described in section 8.7.6.2 of Method 5 except that no
brushing is done. Put all the water wash in one container, seal,
and label.
8.4.2.3 Container No. 3. Rinse and brush the sample nozzle,
probe, and front half of the filter holder with acetone as
described for Container No. 2 in section 8.7.6.2 of Method 5.
8.4.2.4 Container No. 4. Place the contents of the silica gel
impinger in its original container as described for Container No. 3
in section 8.7.6.3 of Method 5.
8.4.2.5 Container No. 5. Measure the liquid in the first three
impingers and record the volume or weight as described for the
Impinger Water in section 8.7.6.4 of Method 5. Do not discard this
liquid, but place it in a sample container using a glass funnel to
aid in the transfer from the impingers or graduated cylinder (if
used) to the sample container. Rinse each impinger thoroughly with
0.1 N NaOH three times, as well as the graduated cylinder (if used)
and the funnel, and put these rinsings in the same sample
container. Seal the container and label to clearly identify its
contents.
8.5 Sample Transport. Whenever possible, containers should be
shipped in such a way that they remain upright at all times.
9.0 Quality Control.
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
8.3, 10.0
Sampling equipment leak-check
and calibration
Ensures accurate measurement
of stack gas flow rate, sample volume.
10.1.2,
11.2.5.3
Repetitive analyses
Ensures precise measurement of
total carbon and inorganic carbon concentration of samples, blank,
and standards.
10.1.4
TOC analyzer calibration
Ensures linearity of analyzer
response to standards.
9.2 Volume Metering System Checks. Same as Method 5, section
9.2.
10.0 Calibration and Standardization
Same as Method 5, section 10.0, with the addition of the
following procedures for calibrating the total organic carbon
analyzer:
10.1 Preparation of Organic Carbon Standard Curve.
10.1.1 Add 10 ml, 20 ml, 30 ml, 40 ml, and 50 ml of the organic
carbon stock solution to a series of five 1000-ml volumetric
flasks. Add 30 ml, 40 ml, and 50 ml of the same solution to a
series of three 500-ml volumetric flasks. Dilute the contents of
each flask to the mark using CO2-free water. These flasks contain
10, 20, 30, 40, 50, 60, 80, and 100 mg/L organic carbon,
respectively.
10.1.2 Use a hypodermic syringe to withdraw a 20- to 50-µl
aliquot from the 10 mg/L standard solution and inject it into the
total carbon port of the analyzer. Measure the peak height. Repeat
the injections until three consecutive peaks are obtained within 10
percent of their arithmetic mean. Repeat this procedure for the
remaining organic carbon standard solutions.
10.1.3 Calculate the corrected peak height for each standard by
deducting the blank correction (see section 11.2.5.3) as
follows:
Where: A = Peak height of standard or sample,
mm or other appropriate unit. B = Peak height of blank, mm or other
appropriate unit.
10.1.4 Prepare a linear regression plot of the arithmetic mean
of the three consecutive peak heights obtained for each standard
solution against the concentration of that solution. Calculate the
calibration factor as the inverse of the slope of this curve. If
the product of the arithmetic mean peak height for any standard
solution and the calibration factor differs from the actual
concentration by more than 5 percent, remake and reanalyze that
standard.
10.2 Preparation of Inorganic Carbon Standard Curve. Repeat the
procedures outlined in sections 10.1.1 through 10.1.4, substituting
the inorganic carbon stock solution for the organic carbon stock
solution, and the inorganic carbon port of the analyzer for the
total carbon port.
11.0 Analytical Procedure
11.1 Record the data required on a sheet such as the one shown
in Figure 5-6 of Method 5.
11.2 Handle each sample container as follows:
11.2.1 Container No. 1. Same as Method 5, section 11.2.1, except
that the filters must be dried at 20 ±6 °C (68 ±10 °F) and ambient
pressure.
11.2.2 Containers No. 2 and No. 3. Same as Method 5, section
11.2.2, except that evaporation of the samples must be at 20 ±6 °C
(68 ±10 °F) and ambient pressure.
11.2.3 Container No. 4. Same as Method 5, section 11.2.3.
11.2.4 “Water Blank” and “Acetone Blank” Containers. Determine
the water and acetone blank values following the procedures for the
“Acetone Blank” container in section 11.2.4 of Method 5. Evaporate
the samples at ambient temperature (20 ±6 °C (68 ±10 °F)) and
pressure.
11.2.5 Container No. 5. For the determination of total organic
carbon, perform two analyses on successive identical samples,
i.e., total carbon and inorganic carbon. The desired
quantity is the difference between the two values obtained. Both
analyses are based on conversion of sample carbon into carbon
dioxide for measurement by a nondispersive infrared analyzer.
Results of analyses register as peaks on a strip chart
recorder.
11.2.5.1 The principal differences between the operating
parameters for the two channels involve the combustion tube packing
material and temperature. In the total carbon channel, a high
temperature (950 °C (1740 °F)) furnace heats a Hastelloy combustion
tube packed with cobalt oxide-impregnated asbestos fiber. The
oxygen in the carrier gas, the elevated temperature, and the
catalytic effect of the packing result in oxidation of both organic
and inorganic carbonaceous material to CO2, and steam. In the
inorganic carbon channel, a low temperature (150 °C (300 °F))
furnace heats a glass tube containing quartz chips wetted with 85
percent phosphoric acid. The acid liberates CO2 and steam from
inorganic carbonates. The operating temperature is below that
required to oxidize organic matter. Follow the manufacturer's
instructions for assembly, testing, calibration, and operation of
the analyzer.
11.2.5.2 As samples collected in 0.1 N NaOH often contain a high
measure of inorganic carbon that inhibits repeatable determinations
of TOC, sample pretreatment is necessary. Measure and record the
liquid volume of each sample (or impinger contents). If the sample
contains solids or immiscible liquid matter, homogenize the sample
with a blender or ultrasonics until satisfactory repeatability is
obtained. Transfer a representative portion of 10 to 15 ml to a
30-ml beaker, and acidify with about 2 drops of concentrated HCl to
a pH of 2 or less. Warm the acidified sample at 50 °C (120 °F) in a
water bath for 15 minutes.
11.2.5.3 While stirring the sample with a magnetic stirrer, use
a hypodermic syringe to withdraw a 20-to 50-µ1 aliquot from the
beaker. Analyze the sample for total carbon and calculate its
corrected mean peak height according to the procedures outlined in
sections 10.1.2 and 10.1.3. Similarly analyze an aliquot of the
sample for inorganic carbon. Repeat the analyses for all the
samples and for the 0.1 N NaOH blank.
11.2.5.4 Ascertain the total carbon and inorganic carbon
concentrations (CTC and CIC, respectively) of each sample and blank
by comparing the corrected mean peak heights for each sample and
blank to the appropriate standard curve.
Note:
If samples must be diluted for analysis, apply an appropriate
dilution factor.
12.0 Data Analysis and Calculations
Same as Method 5, section 12.0, with the addition of the
following:
12.1 Nomenclature.
Cc = Concentration of condensed particulate matter in stack gas,
gas dry basis, corrected to standard conditions, g/dscm (gr/dscf).
CIC = Concentration of condensed TOC in the liquid sample, from
section 11.2.5, mg/L. Ct = Total particulate concentration, dry
basis, corrected to standard conditions, g/dscm (gr/dscf). CTC =
Concentration of condensed TOC in the liquid sample, from section
11.2.5, mg/L. CTOC = Concentration of condensed TOC in the liquid
sample, mg/L. mTOC = Mass of condensed TOC collected in the
impingers, mg. Vm(std) = Volume of gas sample measured by the dry
gas meter, corrected to standard conditions, from section 12.3 of
Method 5, dscm (dscf). Vs = Total volume of liquid sample, ml.
12.2 Concentration of Condensed TOC in Liquid Sample.
12.3 Mass of Condensed TOC Collected.
Where: 0.001 = Liters per milliliter.
12.4 Concentration of Condensed Particulate Material.
Where: K4 = 0.001 g/mg for metric units. =
0.0154 gr/mg for English units.
16.1 Total Organic Carbon Analyzer. Tekmar-Dohrmann analyzers
using the single injection technique may be used as an alternative
to Rosemount Model 2100A analyzers.
17.0 References.
Same as section 17.0 of Method 5, with the addition of the
following:
1. American Public Health Association, American Water Works
Association, Water Pollution Control Federation. Standard Methods
for the Examination of Water and Wastewater. Fifteenth Edition.
Washington, D.C. 1980.
18.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
Method 5F - Determination of Nonsulfate Particulate Matter
Emissions From Stationary Sources Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, and Method
5.
1.0 Scope and Applications
1.1 Analyte. Nonsulfate particulate matter (PM). No CAS number
assigned.
1.2 Applicability. This method is applicable for the
determination of nonsulfate PM emissions from stationary sources.
Use of this method must be specified by an applicable subpart of
the standards, or approved by the Administrator for a particular
application.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
Particulate matter is withdrawn isokinetically from the source
and collected on a filter maintained at a temperature in the range
160 ±14 °C (320 ±25 °F). The collected sample is extracted with
water. A portion of the extract is analyzed for sulfate content by
ion chromatography. The remainder is neutralized with ammonium
hydroxide (NH4OH), dried, and weighed. The weight of sulfate in the
sample is calculated as ammonium sulfate ((NH4)2SO4), and is
subtracted from the total particulate weight; the result is
reported as nonsulfate particulate matter.
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies
6.1 Sample Collection and Recovery. Same as Method 5, sections
6.1 and 6.2, respectively.
6.2 Sample Analysis. Same as Method 5, section 6.3, with the
addition of the following:
6.2.1 Erlenmeyer Flasks. 125-ml, with ground glass joints.
6.2.2 Air Condenser. With ground glass joint compatible with the
Erlenmeyer flasks.
6.2.3 Beakers. 600-ml.
6.2.4 Volumetric Flasks. 1-liter, 500-ml (one for each sample),
200-ml, and 50-ml (one for each sample and standard).
6.2.5 Pipet. 5-ml (one for each sample and standard).
6.2.6 Ion Chromatograph. The ion chromatograph should have at
least the following components.
6.2.6.1 Columns. An anion separation column or other column
capable of resolving the sulfate ion from other species present and
a standard anion suppressor column. Suppressor columns are produced
as proprietary items; however, one can be produced in the
laboratory using the resin available from BioRad Company, 32nd and
Griffin Streets, Richmond, California. Other systems which do not
use suppressor columns may also be used.
6.2.6.2 Pump. Capable of maintaining a steady flow as required
by the system.
6.2.6.3 Flow Gauges. Capable of measuring the specified system
flow rate.
6.2.6.4 Conductivity Detector.
6.2.6.5 Recorder. Compatible with the output voltage range of
the detector.
7.0 Reagents and Standards
Unless otherwise indicated, it is intended that all reagents
conform to the specifications established by the Committee on
Analytical Reagents of the American Chemical Society, where such
specifications are available; otherwise, use the best available
grade.
7.1 Sample Collection. Same as Method 5, section 7.1.
7.2 Sample Recovery. Same as Method 5, section 7.2, with the
addition of the following:
7.2.1 Water. Deionized distilled, to conform to ASTM D 1193-77
or 91 Type 3 (incorporated by reference - see § 60.17). The
potassium permanganate (KMnO4) test for oxidizable organic matter
may be omitted when high concentrations of organic matter are not
expected to be present.
7.3 Analysis. Same as Method 5, section 7.3, with the addition
of the following:
7.3.1 Water. Same as in section 7.2.1.
7.3.2 Stock Standard Solution, 1 mg (NH4)2SO4/ml. Dry an
adequate amount of primary standard grade ammonium sulfate
((NH4)2SO4) at 105 to 110 °C (220 to 230 °F) for a minimum of 2
hours before preparing the standard solution. Then dissolve exactly
1.000 g of dried (NH4)2SO4 in water in a 1-liter volumetric flask,
and dilute to 1 liter. Mix well.
7.3.3 Working Standard Solution, 25 µg (NH4)2SO4/ml. Pipet 5 ml
of the stock standard solution into a 200-ml volumetric flask.
Dilute to 200 ml with water.
7.3.4 Eluent Solution. Weigh 1.018 g of sodium carbonate
(Na2CO3) and 1.008 g of sodium bicarbonate (NaHCO3), and dissolve
in 4 liters of water. This solution is 0.0024 M Na2CO3/0.003 M
NaHCO3. Other eluents appropriate to the column type and capable of
resolving sulfate ion from other species present may be used.
7.3.5 Ammonium Hydroxide. Concentrated, 14.8 M.
7.3.6 Phenolphthalein Indicator.
3,3-Bis(4-hydroxyphenyl)-1-(3H)-isobenzo-furanone. Dissolve 0.05 g
in 50 ml of ethanol and 50 ml of water.
8.0 Sample Collection, Preservation, Storage, and Transport
Same as Method 5, section 8.0, with the exception of the
following:
8.1 Sampling Train Operation. Same as Method 5, section 8.5,
except that the probe outlet and filter temperatures shall be
maintained at 160 ±14 °C (320 ±25 °F).
8.2 Sample Recovery. Same as Method 5, section 8.7, except that
the recovery solvent shall be water instead of acetone, and a clean
filter from the same lot as those used during testing shall be
saved for analysis as a blank.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures
Section
Quality control measure
Effect
8.3, 10.0
Sampling equipment leak check
and calibration
Ensures accurate measurement
of stack gas flow rate, sample volume.
10.1.2,
11.2.5.3
Repetitive analyses
Ensures precise measurement of
total carbon and inorganic carbon concentration of samples, blank,
and standards.
9.2 Volume Metering System Checks. Same as Method 5, section
9.2.
10.0 Calibration and Standardization
Same as Method 5, section 10.0, with the addition of the
following:
10.1 Determination of Ion Chromatograph Calibration Factor S.
Prepare a series of five standards by adding 1.0, 2.0, 4.0, 6.0,
and 10.0 ml of working standard solution (25 µg/ml) to a series of
five 50-ml volumetric flasks. (The standard masses will equal 25,
50, 100, 150, and 250 µg.) Dilute each flask to the mark with
water, and mix well. Analyze each standard according to the
chromatograph manufacturer's instructions. Take peak height
measurements with symmetrical peaks; in all other cases, calculate
peak areas. Prepare or calculate a linear regression plot of the
standard masses in µg (x-axis) versus their responses (y-axis).
From this line, or equation, determine the slope and calculate its
reciprocal which is the calibration factor, S. If any point
deviates from the line by more than 7 percent of the concentration
at that point, remake and reanalyze that standard. This deviation
can be determined by multiplying S times the response for each
standard. The resultant concentrations must not differ by more than
7 percent from each known standard mass (i.e., 25, 50, 100,
150, and 250 µg).
10.2 Conductivity Detector. Calibrate according to
manufacturer's specifications prior to initial use.
11.0 Analytical Procedure
11.1 Sample Extraction.
11.1.1 Note on the analytical data sheet, the level of the
liquid in the container, and whether any sample was lost during
shipment. If a noticeable amount of leakage has occurred, either
void the sample or use methods, subject to the approval of the
Administrator, to correct the final results.
11.1.2 Cut the filter into small pieces, and place it in a
125-ml Erlenmeyer flask with a ground glass joint equipped with an
air condenser. Rinse the shipping container with water, and pour
the rinse into the flask. Add additional water to the flask until
it contains about 75 ml, and place the flask on a hot plate. Gently
reflux the contents for 6 to 8 hours. Cool the solution, and
transfer it to a 500-ml volumetric flask. Rinse the Erlenmeyer
flask with water, and transfer the rinsings to the volumetric flask
including the pieces of filter.
11.1.3 Transfer the probe rinse to the same 500-ml volumetric
flask with the filter sample. Rinse the sample bottle with water,
and add the rinsings to the volumetric flask. Dilute the contents
of the flask to the mark with water.
11.1.4 Allow the contents of the flask to settle until all solid
material is at the bottom of the flask. If necessary, remove and
centrifuge a portion of the sample.
11.1.5 Repeat the procedures outlined in sections 11.1.1 through
11.1.4 for each sample and for the filter blank.
11.2 Sulfate (SO4) Analysis.
11.2.1 Prepare a standard calibration curve according to the
procedures outlined in section 10.1.
11.2.2 Pipet 5 ml of the sample into a 50-ml volumetric flask,
and dilute to 50 ml with water. (Alternatively, eluent solution may
be used instead of water in all sample, standard, and blank
dilutions.) Analyze the set of standards followed by the set of
samples, including the filter blank, using the same injection
volume used for the standards.
11.2.3 Repeat the analyses of the standards and the samples,
with the standard set being done last. The two peak height or peak
area responses for each sample must agree within 5 percent of their
arithmetic mean for the analysis to be valid. Perform this analysis
sequence on the same day. Dilute any sample and the blank with
equal volumes of water if the concentration exceeds that of the
highest standard.
11.2.4 Document each sample chromatogram by listing the
following analytical parameters: injection point, injection volume,
sulfate retention time, flow rate, detector sensitivity setting,
and recorder chart speed.
11.3 Sample Residue.
11.3.1 Transfer the remaining contents of the volumetric flask
to a tared 600-ml beaker or similar container. Rinse the volumetric
flask with water, and add the rinsings to the tared beaker. Make
certain that all particulate matter is transferred to the beaker.
Evaporate the water in an oven at 105 °C (220 °F) until only about
100 ml of water remains. Remove the beakers from the oven, and
allow them to cool.
11.3.2 After the beakers have cooled, add five drops of
phenolphthalein indicator, and then add concentrated ammonium
hydroxide until the solution turns pink. Return the samples to the
oven at 105 °C (220 °F), and evaporate the samples to dryness. Cool
the samples in a desiccator, and weigh the samples to constant
weight.
12.0 Data Analysis and Calculations
Same as Method 5, section 12.0, with the addition of the
following:
12.1 Nomenclature.
CW = Water blank residue concentration, mg/ml. F = Dilution factor
(required only if sample dilution was needed to reduce the
concentration into the range of calibration). HS = Arithmetic mean
response of duplicate sample analyses, mm for height or mm2 for
area. Hb = Arithmetic mean response of duplicate filter blank
analyses, mm for height or mm2 for area. mb = Mass of beaker used
to dry sample, mg. mf = Mass of sample filter, mg. mn = Mass of
nonsulfate particulate matter in the sample as collected, mg. ms =
Mass of ammonium sulfate in the sample as collected, mg. mt = Mass
of beaker, filter, and dried sample, mg. mw = Mass of residue after
evaporation of water blank, mg. S = Calibration factor, µg/mm. Vb =
Volume of water blank, ml. VS = Volume of sample collected, 500 ml.
12.2 Water Blank Concentration.
12.3 Mass of Ammonium Sulfate.
Where: 100 = Aliquot factor, 495 ml/5 ml 1000 =
Constant, µg/mg
16.1.1.5 Volumetric Flasks. 50-ml and 500-ml, one set for each
sample, and 100-ml, 200-ml, and 1000-ml.
16.1.1.6 Pipettes. Two 20-ml and one 200-ml, one set for each
sample, and 5-ml.
16.1.1.7 Filter Flasks. 500-ml.
16.1.1.8 Polyethylene Bottle. 500-ml, one for each sample.
16.1.2 Reagents. Same as Method 6, sections 7.3.2 to 7.3.5 with
the following additions:
16.1.2.1 Water, Ammonium Hydroxide, and Phenolphthalein. Same as
sections 7.2.1, 7.3.5, and 7.3.6 of this method, respectively.
16.1.2.2 Filter. Glass fiber to fit Buchner funnel.
16.1.2.3 Hydrochloric Acid (HCl), 1 m. Add 8.3 ml of
concentrated HCl (12 M) to 50 ml of water in a 100-ml volumetric
flask. Dilute to 100 ml with water.
16.1.3.1 Ion Exchange Column Preparation. Slurry the resin with
1 M HCl in a 250-ml beaker, and allow to stand overnight. Place 2.5
cm (1 in.) of glass wool in the bottom of the glass column. Rinse
the slurried resin twice with water. Resuspend the resin in water,
and pour sufficient resin into the column to make a bed 5.1 cm (2
in.) deep. Do not allow air bubbles to become entrapped in the
resin or glass wool to avoid channeling, which may produce erratic
results. If necessary, stir the resin with a glass rod to remove
air bubbles, after the column has been prepared, never let the
liquid level fall below the top of the upper glass wool plug. Place
a 2.5-cm (1-in.) plug of glass wool on top of the resin. Rinse the
column with water until the eluate gives a pH of 5 or greater as
measured with pH paper.
16.1.3.2 Sample Extraction. Followup the procedure given in
section 11.1.3 except do not dilute the sample to 500 ml.
16.1.3.3 Sample Residue.
16.1.3.3.1 Place at least one clean glass filter for each sample
in a Buchner funnel, and rinse the filters with water. Remove the
filters from the funnel, and dry them in an oven at 105 ±5 °C (221
±9 °F); then cool in a desiccator. Weigh each filter to constant
weight according to the procedure in Method 5, section 11.0. Record
the weight of each filter to the nearest 0.1 mg.
16.1.3.3.2 Assemble the vacuum filter apparatus, and place one
of the clean, tared glass fiber filters in the Buchner funnel.
Decant the liquid portion of the extracted sample (Section
16.1.3.2) through the tared glass fiber filter into a clean, dry,
500-ml filter flask. Rinse all the particulate matter remaining in
the volumetric flask onto the glass fiber filter with water. Rinse
the particulate matter with additional water. Transfer the filtrate
to a 500-ml volumetric flask, and dilute to 500 ml with water. Dry
the filter overnight at 105 ±5 °C (221 ±9 °F), cool in a
desiccator, and weigh to the nearest 0.1 mg.
16.1.3.3.3 Dry a 250-ml beaker at 75 ±5 °C (167 ±9 °F), and cool
in a desiccator; then weigh to constant weight to the nearest 0.1
mg. Pipette 200 ml of the filtrate that was saved into a tared
250-ml beaker; add five drops of phenolphthalein indicator and
sufficient concentrated ammonium hydroxide to turn the solution
pink. Carefully evaporate the contents of the beaker to dryness at
75 ±5 °C (167 ±9 °F). Check for dryness every 30 minutes. Do not
continue to bake the sample once it has dried. Cool the sample in a
desiccator, and weigh to constant weight to the nearest 0.1 mg.
16.1.3.4 Sulfate Analysis. Adjust the flow rate through the ion
exchange column to 3 ml/min. Pipette a 20-ml aliquot of the
filtrate onto the top of the ion exchange column, and collect the
eluate in a 50-ml volumetric flask. Rinse the column with two 15-ml
portions of water. Stop collection of the eluate when the volume in
the flask reaches 50-ml. Pipette a 20-ml aliquot of the eluate into
a 250-ml Erlenmeyer flask, add 80 ml of 100 percent isopropanol and
two to four drops of thorin indicator, and titrate to a pink end
point using 0.0100 N barium perchlorate. Repeat and average the
titration volumes. Run a blank with each series of samples.
Replicate titrations must agree within 1 percent or 0.2 ml,
whichever is larger. Perform the ion exchange and titration
procedures on duplicate portions of the filtrate. Results should
agree within 5 percent. Regenerate or replace the ion exchange
resin after 20 sample aliquots have been analyzed or if the end
point of the titration becomes unclear.
Note:
Protect the 0.0100 N barium perchlorate solution from
evaporation at all times.
16.1.3.5 Blank Determination. Begin with a sample of water of
the same volume as the samples being processed and carry it through
the analysis steps described in sections 16.1.3.3 and 16.1.3.4. A
blank value larger than 5 mg should not be subtracted from the
final particulate matter mass. Causes for large blank values should
be investigated and any problems resolved before proceeding with
further analyses.
16.1.4 Calibration. Calibrate the barium perchlorate solutions
as in Method 6, section 10.5.
16.1.5 Calculations.
16.1.5.1 Nomenclature. Same as section 12.1 with the following
additions:
ma = Mass of clean analytical filter, mg. md = Mass of dissolved
particulate matter, mg. me = Mass of beaker and dissolved
particulate matter after evaporation of filtrate, mg. mp = Mass of
insoluble particulate matter, mg. mr = Mass of analytical filter,
sample filter, and insoluble particulate matter, mg. mbk = Mass of
nonsulfate particulate matter in blank sample, mg. mn = Mass of
nonsulfate particulate matter, mg. ms = Mass of Ammonium sulfate,
mg. N = Normality of Ba(ClO4) titrant, meq/ml. Va = Volume of
aliquot taken for titration, 20 ml. Vc = Volume of titrant used for
titration blank, ml. Vd = Volume of filtrate evaporated, 200 ml. Ve
= Volume of eluate collected, 50 ml. Vf = Volume of extracted
sample, 500 ml. Vi = Volume of filtrate added to ion exchange
column, 20 ml. Vt = Volume of Ba(C104)2 titrant, ml. W = Equivalent
weight of ammonium sulfate, 66.07 mg/meq.
16.1.5.2 Mass of Insoluble Particulate Matter.
16.1.5.3 Mass of Dissolved Particulate Matter.
16.1.5.4 Mass of Ammonium Sulfate.
16.1.5.5 Mass of Nonsulfate Particulate Matter.
17.0 References
Same as Method 5, section 17.0, with the addition of the
following:
1. Mulik, J.D. and E. Sawicki. Ion Chromatographic Analysis of
Environmental Pollutants. Ann Arbor, Ann Arbor Science Publishers,
Inc. Vol. 2, 1979.
2. Sawicki, E., J.D. Mulik, and E. Wittgenstein. Ion
Chromatographic Analysis of Environmental Pollutants. Ann Arbor,
Ann Arbor Science Publishers, Inc. Vol. 1. 1978.
3. Siemer, D.D. Separation of Chloride and Bromide from Complex
Matrices Prior to Ion Chromatographic Determination. Analytical
Chemistry 52(12): 1874-1877. October 1980.
4. Small, H., T.S. Stevens, and W.C. Bauman. Novel Ion Exchange
Chromatographic Method Using Conductimetric Determination.
Analytical Chemistry. 47(11):1801. 1975.
18.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
Method 5G - Determination of Particulate Matter Emissions From Wood
Heaters (Dilution Tunnel Sampling Location) Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, Method 4,
Method 5, Method 5H, and Method 28.
1.0 Scope and Application
1.1 Analyte. Particulate matter (PM). No CAS number
assigned.
1.2 Applicability. This method is applicable for the
determination of PM emissions from wood heaters.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 The exhaust from a wood heater is collected with a total
collection hood, and is combined with ambient dilution air.
Particulate matter is withdrawn proportionally from a single point
in a sampling tunnel, and is collected on two glass fiber filters
in series. The filters are maintained at a temperature of no
greater than 32 °C (90 °F). The particulate mass is determined
gravimetrically after the removal of uncombined water.
2.2 There are three sampling train approaches described in this
method: (1) One dual-filter dry sampling train operated at about
0.015 m 3/min (0.5 cfm), (2) One dual-filter plus impingers
sampling train operated at about 0.015 m 3/min (0.5 cfm), and (3)
two dual-filter dry sampling trains operated simultaneously at any
flow rate. Options (2) and (3) are referenced in section 16.0 of
this method. The dual-filter dry sampling train equipment and
operation, option (1), are described in detail in this method.
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies
6.1 Sample Collection. The following items are required for
sample collection:
6.1.1 Sampling Train. The sampling train configuration is shown
in Figure 5G-1 and consists of the following components:
6.1.1.1 Probe. Stainless steel (e.g., 316 or grade more
corrosion resistant) or glass about 9.5 mm ( 3/8 in.) I.D., 0.6 m
(24 in.) in length. If made of stainless steel, the probe shall be
constructed from seamless tubing.
6.1.1.2 Pitot Tube. Type S, as described in section 6.1 of
Method 2. The Type S pitot tube assembly shall have a known
coefficient, determined as outlined in Method 2, section 10.
Alternatively, a standard pitot may be used as described in Method
2, section 6.1.2.
6.1.1.3 Differential Pressure Gauge. Inclined manometer or
equivalent device, as described in Method 2, section 6.2. One
manometer shall be used for velocity head (Δp) readings and another
(optional) for orifice differential pressure readings (ΔH).
6.1.1.4 Filter Holders. Two each made of borosilicate glass,
stainless steel, or Teflon, with a glass frit or stainless steel
filter support and a silicone rubber, Teflon, or Viton gasket. The
holder design shall provide a positive seal against leakage from
the outside or around the filters. The filter holders shall be
placed in series with the backup filter holder located 25 to 100 mm
(1 to 4 in.) downstream from the primary filter holder. The filter
holder shall be capable of holding a filter with a 100 mm (4 in.)
diameter, except as noted in section 16.
6.1.1.5 Filter Temperature Monitoring System. A temperature
sensor capable of measuring temperature to within ±3 °C (±5 °F).
The sensor shall be installed at the exit side of the front filter
holder so that the sensing tip of the temperature sensor is in
direct contact with the sample gas or in a thermowell as shown in
Figure 5G-1. The temperature sensor shall comply with the
calibration specifications in Method 2, section 10.3.
Alternatively, the sensing tip of the temperature sensor may be
installed at the inlet side of the front filter holder.
6.1.1.6 Dryer. Any system capable of removing water from the
sample gas to less than 1.5 percent moisture (volume percent) prior
to the metering system. The system shall include a temperature
sensor for demonstrating that sample gas temperature exiting the
dryer is less than 20 °C (68 °F).
6.1.1.7 Metering System. Same as Method 5, section 6.1.1.9.
6.1.2 Barometer. Same as Method 5, section 6.1.2.
6.1.3 Dilution Tunnel Gas Temperature Measurement. A temperature
sensor capable of measuring temperature to within ±3 °C (±5
°F).
6.1.4 Dilution Tunnel. The dilution tunnel apparatus is shown in
Figure 5G-2 and consists of the following components:
6.1.4.1 Hood. Constructed of steel with a minimum diameter of
0.3 m (1 ft) on the large end and a standard 0.15 to 0.3 m (0.5 to
1 ft) coupling capable of connecting to standard 0.15 to 0.3 m (0.5
to 1 ft) stove pipe on the small end.
6.1.4.2 90° Elbows. Steel 90° elbows, 0.15 to 0.3 m (0.5 to 1
ft) in diameter for connecting mixing duct, straight duct and
optional damper assembly. There shall be at least two 90° elbows
upstream of the sampling section (see Figure 5G-2).
6.1.4.3 Straight Duct. Steel, 0.15 to 0.3 m (0.5 to 1 ft) in
diameter to provide the ducting for the dilution apparatus upstream
of the sampling section. Steel duct, 0.15 m (0.5 ft) in diameter
shall be used for the sampling section. In the sampling section, at
least 1.2 m (4 ft) downstream of the elbow, shall be two holes
(velocity traverse ports) at 90° to each other of sufficient size
to allow entry of the pitot for traverse measurements. At least 1.2
m (4 ft) downstream of the velocity traverse ports, shall be one
hole (sampling port) of sufficient size to allow entry of the
sampling probe. Ducts of larger diameter may be used for the
sampling section, provided the specifications for minimum gas
velocity and the dilution rate range shown in section 8 are
maintained. The length of duct from the hood inlet to the sampling
ports shall not exceed 9.1 m (30 ft).
6.1.4.4 Mixing Baffles. Steel semicircles (two) attached at 90°
to the duct axis on opposite sides of the duct midway between the
two elbows upstream of sampling section. The space between the
baffles shall be about 0.3 m (1 ft).
6.1.4.5 Blower. Squirrel cage or other fan capable of extracting
gas from the dilution tunnel of sufficient flow to maintain the
velocity and dilution rate specifications in section 8 and
exhausting the gas to the atmosphere.
6.2 Sample Recovery. The following items are required for sample
recovery: probe brushes, wash bottles, sample storage containers,
petri dishes, and funnel. Same as Method 5, sections 6.2.1 through
6.2.4, and 6.2.8, respectively.
6.3 Sample Analysis. The following items are required for sample
analysis: glass weighing dishes, desiccator, analytical balance,
beakers (250-ml or smaller), hygrometer, and temperature sensor.
Same as Method 5, sections 6.3.1 through 6.3.3 and 6.3.5 through
6.3.7, respectively.
7.0 Reagents and Standards
7.1 Sample Collection. The following reagents are required for
sample collection:
7.1.1 Filters. Glass fiber filters with a minimum diameter of
100 mm (4 in.), without organic binder, exhibiting at least 99.95
percent efficiency (<0.05 percent penetration) on 0.3-micron
dioctyl phthalate smoke particles. Gelman A/E 61631 has been found
acceptable for this purpose.
7.1.2 Stopcock Grease. Same as Method 5, section 7.1.5. 7.2
Sample Recovery. Acetone-reagent grade, same as Method 5, section
7.2.
7.3 Sample Analysis. Two reagents are required for the sample
analysis:
8.0 Sample Collection, Preservation, Transport, and Storage
8.1 Dilution Tunnel Assembly and Cleaning. A schematic of a
dilution tunnel is shown in Figure 5G-2. The dilution tunnel
dimensions and other features are described in section 6.1.4.
Assemble the dilution tunnel, sealing joints and seams to prevent
air leakage. Clean the dilution tunnel with an appropriately sized
wire chimney brush before each certification test.
8.2 Draft Determination. Prepare the wood heater as in Method
28, section 6.2.1. Locate the dilution tunnel hood centrally over
the wood heater stack exhaust. Operate the dilution tunnel blower
at the flow rate to be used during the test run. Measure the draft
imposed on the wood heater by the dilution tunnel (i.e., the
difference in draft measured with and without the dilution tunnel
operating) as described in Method 28, section 6.2.3. Adjust the
distance between the top of the wood heater stack exhaust and the
dilution tunnel hood so that the dilution tunnel induced draft is
less than 1.25 Pa (0.005 in. H2O). Have no fire in the wood heater,
close the wood heater doors, and open fully the air supply controls
during this check and adjustment.
8.3 Pretest Ignition. Same as Method 28, section 8.7.
8.4 Smoke Capture. During the pretest ignition period, operate
the dilution tunnel and visually monitor the wood heater stack
exhaust. Operate the wood heater with the doors closed and
determine that 100 percent of the exhaust gas is collected by the
dilution tunnel hood. If less than 100 percent of the wood heater
exhaust gas is collected, adjust the distance between the wood
heater stack and the dilution tunnel hood until no visible exhaust
gas is escaping. Stop the pretest ignition period, and repeat the
draft determination procedure described in section 8.2.
8.5 Velocity Measurements. During the pretest ignition period,
conduct a velocity traverse to identify the point of average
velocity. This single point shall be used for measuring velocity
during the test run.
8.5.1 Velocity Traverse. Measure the diameter of the duct at the
velocity traverse port location through both ports. Calculate the
duct area using the average of the two diameters. A pretest
leak-check of pitot lines as in Method 2, section 8.1, is
recommended. Place the calibrated pitot tube at the centroid of the
stack in either of the velocity traverse ports. Adjust the damper
or similar device on the blower inlet until the velocity indicated
by the pitot is approximately 220 m/min (720 ft/min). Continue to
read the Δp and temperature until the velocity has remained
constant (less than 5 percent change) for 1 minute. Once a constant
velocity is obtained at the centroid of the duct, perform a
velocity traverse as outlined in Method 2, section 8.3 using four
points per traverse as outlined in Method 1. Measure the Δp and
tunnel temperature at each traverse point and record the readings.
Calculate the total gas flow rate using calculations contained in
Method 2, section 12. Verify that the flow rate is 4 ±0.40 dscm/min
(140 ±14 dscf/min); if not, readjust the damper, and repeat the
velocity traverse. The moisture may be assumed to be 4 percent (100
percent relative humidity at 85 °F). Direct moisture measurements
(e.g., according to Method 4) are also permissible.
Note:
If burn rates exceed 3 kg/hr (6.6 lb/hr), dilution tunnel duct
flow rates greater than 4 dscm/min (140 dscfm) and sampling section
duct diameters larger than 150 mm (6 in.) are allowed. If larger
ducts or flow rates are used, the sampling section velocity shall
be at least 220 m/min (720 fpm). In order to ensure measurable
particulate mass catch, it is recommended that the ratio of the
average mass flow rate in the dilution tunnel to the average fuel
burn rate be less than 150:1 if larger duct sizes or flow rates are
used.
8.5.2 Testing Velocity Measurements. After obtaining velocity
traverse results that meet the flow rate requirements, choose a
point of average velocity and place the pitot and temperature
sensor at that location in the duct. Alternatively, locate the
pitot and the temperature sensor at the duct centroid and calculate
a velocity correction factor for the centroidal position. Mount the
pitot to ensure no movement during the test run and seal the port
holes to prevent any air leakage. Align the pitot opening to be
parallel with the duct axis at the measurement point. Check that
this condition is maintained during the test run (about 30-minute
intervals). Monitor the temperature and velocity during the pretest
ignition period to ensure that the proper flow rate is maintained.
Make adjustments to the dilution tunnel flow rate as necessary.
8.6 Pretest Preparation. Same as Method 5, section 8.1.
8.7 Preparation of Sampling Train. During preparation and
assembly of the sampling train, keep all openings where
contamination can occur covered until just prior to assembly or
until sampling is about to begin.
Using a tweezer or clean disposable surgical gloves, place one
labeled (identified) and weighed filter in each of the filter
holders. Be sure that each filter is properly centered and that the
gasket is properly placed so as to prevent the sample gas stream
from circumventing the filter. Check each filter for tears after
assembly is completed.
Mark the probe with heat resistant tape or by some other method
to denote the proper distance into the stack or duct. Set up the
train as shown in Figure 5G-1.
8.8 Leak-Check Procedures.
8.8.1 Leak-Check of Metering System Shown in Figure 5G-1. That
portion of the sampling train from the pump to the orifice meter
shall be leak-checked prior to initial use and after each
certification or audit test. Leakage after the pump will result in
less volume being recorded than is actually sampled. Use the
procedure described in Method 5, section 8.4.1. Similar leak-checks
shall be conducted for other types of metering systems
(i.e., without orifice meters).
8.8.2 Pretest Leak-Check. A pretest leak-check of the sampling
train is recommended, but not required. If the pretest leak check
is conducted, the procedures outlined in Method 5, section 8.4.2
should be used. A vacuum of 130 mm Hg (5 in. Hg) may be used
instead of 380 mm Hg (15 in. Hg).
8.8.3 Post-Test Leak-Check. A leak-check of the sampling train
is mandatory at the conclusion of each test run. The leak-check
shall be performed in accordance with the procedures outlined in
Method 5, section 8.4.2. A vacuum of 130 mm Hg (5 in. Hg) or the
highest vacuum measured during the test run, whichever is greater,
may be used instead of 380 mm Hg (15 in. Hg).
8.9 Preliminary Determinations. Determine the pressure,
temperature and the average velocity of the tunnel gases as in
section 8.5. Moisture content of diluted tunnel gases is assumed to
be 4 percent for making flow rate calculations; the moisture
content may be measured directly as in Method 4.
8.10 Sampling Train Operation. Position the probe inlet at the
stack centroid, and block off the openings around the probe and
porthole to prevent unrepresentative dilution of the gas stream. Be
careful not to bump the probe into the stack wall when removing or
inserting the probe through the porthole; this minimizes the chance
of extracting deposited material.
8.10.1 Begin sampling at the start of the test run as defined in
Method 28, section 8.8.1. During the test run, maintain a sample
flow rate proportional to the dilution tunnel flow rate (within 10
percent of the initial proportionality ratio) and a filter holder
temperature of no greater than 32 °C (90 °F). The initial sample
flow rate shall be approximately 0.015 m 3/min (0.5 cfm).
8.10.2 For each test run, record the data required on a data
sheet such as the one shown in Figure 5G-3. Be sure to record the
initial dry gas meter reading. Record the dry gas meter readings at
the beginning and end of each sampling time increment and when
sampling is halted. Take other readings as indicated on Figure 5G-3
at least once each 10 minutes during the test run. Since the
manometer level and zero may drift because of vibrations and
temperature changes, make periodic checks during the test run.
8.10.3 For the purposes of proportional sampling rate
determinations, data from calibrated flow rate devices, such as
glass rotameters, may be used in lieu of incremental dry gas meter
readings. Proportional rate calculation procedures must be revised,
but acceptability limits remain the same.
8.10.4 During the test run, make periodic adjustments to keep
the temperature between (or upstream of) the filters at the proper
level. Do not change sampling trains during the test run.
8.10.5 At the end of the test run (see Method 28, section
6.4.6), turn off the coarse adjust valve, remove the probe from the
stack, turn off the pump, record the final dry gas meter reading,
and conduct a post-test leak-check, as outlined in section 8.8.2.
Also, leak-check the pitot lines as described in Method 2, section
8.1; the lines must pass this leak-check in order to validate the
velocity head data.
8.11 Calculation of Proportional Sampling Rate. Calculate
percent proportionality (see section 12.7) to determine whether the
run was valid or another test run should be made.
8.12 Sample Recovery. Same as Method 5, section 8.7, with the
exception of the following:
8.12.1 An acetone blank volume of about 50-ml or more may be
used.
8.12.2 Treat the samples as follows:
8.12.2.1 Container Nos. 1 and 1A. Treat the two filters
according to the procedures outlined in Method 5, section 8.7.6.1.
The filters may be stored either in a single container or in
separate containers. Use the sum of the filter tare weights to
determine the sample mass collected.
8.12.2.3 Container No. 2.
8.12.2.3.1 Taking care to see that dust on the outside of the
probe or other exterior surfaces does not get into the sample,
quantitatively recover particulate matter or any condensate from
the probe and filter holders by washing and brushing these
components with acetone and placing the wash in a labeled glass
container. At least three cycles of brushing and rinsing are
required.
8.12.2.3.2 Between sampling runs, keep brushes clean and
protected from contamination.
8.12.2.3.3 After all acetone washings and particulate matter
have been collected in the sample containers, tighten the lids on
the sample containers so that the acetone will not leak out when
transferred to the laboratory weighing area. Mark the height of the
fluid levels to determine whether leakage occurs during transport.
Label the containers clearly to identify contents.
8.13 Sample Transport. Whenever possible, containers should be
shipped in such a way that they remain upright at all times.
Note:
Requirements for capping and transport of sample containers are
not applicable if sample recovery and analysis occur in the same
room.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
8.8,
10.1-10.4
Sampling equipment leak check
and calibration
Ensures accurate measurement
of stack gas flow rate, sample volume.
10.5
Analytical balance
calibration
Ensure accurate and precise
measurement of collected particulate.
16.2.5
Simultaneous, dual-train
sample collection
Ensure precision of measured
particulate concentration.
9.2 Volume Metering System Checks. Same as Method 5, section
9.2.
10.0 Calibration and Standardization Note:
Maintain a laboratory record of all calibrations.
10.1 Pitot Tube. The Type S pitot tube assembly shall be
calibrated according to the procedure outlined in Method 2, section
10.1, prior to the first certification test and checked
semiannually, thereafter. A standard pitot need not be calibrated
but shall be inspected and cleaned, if necessary, prior to each
certification test.
10.2 Volume Metering System.
10.2.1 Initial and Periodic Calibration. Before its initial use
and at least semiannually thereafter, calibrate the volume metering
system as described in Method 5, section 10.3.1, except that the
wet test meter with a capacity of 3.0 liters/rev (0.1 ft 3/rev) may
be used. Other liquid displacement systems accurate to within ±1
percent, may be used as calibration standards.
Note:
Procedures and equipment specified in Method 5, section 16.0,
for alternative calibration standards, including calibrated dry gas
meters and critical orifices, are allowed for calibrating the dry
gas meter in the sampling train. A dry gas meter used as a
calibration standard shall be recalibrated at least once
annually.
10.2.2 Calibration After Use. After each certification or audit
test (four or more test runs conducted on a wood heater at the four
burn rates specified in Method 28), check calibration of the
metering system by performing three calibration runs at a single,
intermediate flow rate as described in Method 5, section
10.3.2.
Note:
Procedures and equipment specified in Method 5, section 16.0,
for alternative calibration standards are allowed for the post-test
dry gas meter calibration check.
10.2.3 Acceptable Variation in Calibration. If the dry gas meter
coefficient values obtained before and after a certification test
differ by more than 5 percent, the certification test shall either
be voided and repeated, or calculations for the certification test
shall be performed using whichever meter coefficient value
(i.e., before or after) gives the lower value of total
sample volume.
10.3 Temperature Sensors. Use the procedure in Method 2, section
10.3, to calibrate temperature sensors before the first
certification or audit test and at least semiannually,
thereafter.
10.4 Barometer. Calibrate against a mercury barometer before the
first certification test and at least semiannually, thereafter. If
a mercury barometer is used, no calibration is necessary. Follow
the manufacturer's instructions for operation.
10.5 Analytical Balance. Perform a multipoint calibration (at
least five points spanning the operational range) of the analytical
balance before the first certification test and semiannually,
thereafter. Before each certification test, audit the balance by
weighing at least one calibration weight (class F) that corresponds
to 50 to 150 percent of the weight of one filter. If the scale
cannot reproduce the value of the calibration weight to within 0.1
mg, conduct the multipoint calibration before use.
11.0 Analytical Procedure
11.1 Record the data required on a sheet such as the one shown
in Figure 5G-4. Use the same analytical balance for determining
tare weights and final sample weights.
11.2 Handle each sample container as follows:
11.2.1 Container Nos. 1 and 1A. Treat the two filters according
to the procedures outlined in Method 5, section 11.2.1.
11.2.2 Container No. 2. Same as Method 5, section 11.2.2, except
that the beaker may be smaller than 250 ml.
11.2.3 Acetone Blank Container. Same as Method 5, section
11.2.4, except that the beaker may be smaller than 250 ml.
12.0 Data Analysis and Calculations
Carry out calculations, retaining at least one extra significant
figure beyond that of the acquired data. Round off figures after
the final calculation. Other forms of the equations may be used as
long as they give equivalent results.
12.1 Nomenclature.
Bws = Water vapor in the gas stream, proportion by volume (assumed
to be 0.04). cs = Concentration of particulate matter in stack gas,
dry basis, corrected to standard conditions, g/dscm (gr/dscf). E =
Particulate emission rate, g/hr (lb/hr). Eadj = Adjusted
particulate emission rate, g/hr (lb/hr). La = Maximum acceptable
leakage rate for either a pretest or post-test leak-check, equal to
0.00057 m 3/min (0.020 cfm) or 4 percent of the average sampling
rate, whichever is less. Lp = Leakage rate observed during the
post-test leak-check, m 3/min (cfm). ma = Mass of residue of
acetone blank after evaporation, mg. maw = Mass of residue from
acetone wash after evaporation, mg. mn = Total amount of
particulate matter collected, mg. Mw = Molecular weight of water,
18.0 g/g-mole (18.0 lb/lb-mole). Pbar = Barometric pressure at the
sampling site, mm Hg (in. Hg). PR = Percent of proportional
sampling rate. Ps = Absolute gas pressure in dilution tunnel, mm Hg
(in. Hg). Pstd = Standard absolute pressure, 760 mm Hg (29.92 in.
Hg). Qsd = Average gas flow rate in dilution tunnel, calculated as
in Method 2, Equation 2-8, dscm/hr (dscf/hr). Tm = Absolute average
dry gas meter temperature (see Figure 5G-3), °K (°R). Tmi =
Absolute average dry gas meter temperature during each 10-minute
interval, i, of the test run, °K (°R). Ts = Absolute average gas
temperature in the dilution tunnel (see Figure 5G-3), °K (°R). Tsi
= Absolute average gas temperature in the dilution tunnel during
each 10 minute interval, i, of the test run, °K (°R). Tstd =
Standard absolute temperature, 293 °K (528 °R). Va = Volume of
acetone blank, ml. Vaw = Volume of acetone used in wash, ml. Vm =
Volume of gas sample as measured by dry gas meter, dcm (dcf). Vmi =
Volume of gas sample as measured by dry gas meter during each
10-minute interval, i, of the test run, dcm. Vm(std) = Volume of
gas sample measured by the dry gas meter, corrected to standard
conditions, dscm (dscf). Vs = Average gas velocity in the dilution
tunnel, calculated by Method 2, Equation 2-7, m/sec (ft/sec). The
dilution tunnel dry gas molecular weight may be assumed to be 29
g/g mole (lb/lb mole). Vsi = Average gas velocity in dilution
tunnel during each 10-minute interval, i, of the test run,
calculated by Method 2, Equation 2-7, m/sec (ft/sec). Y = Dry gas
meter calibration factor. ΔH = Average pressure differential across
the orifice meter, if used (see Figure 5G-2), mm H 2O (in. H 2O). U
= Total sampling time, min. 10 = 10 minutes, length of first
sampling period. 13.6 = Specific gravity of mercury. 100 =
Conversion to percent.
12.2 Dry Gas Volume. Same as Method 5, section 12.2, except that
component changes are not allowable.
12.3 Solvent Wash Blank.
12.4 Total Particulate Weight. Determine the total particulate
catch, mn, from the sum of the weights obtained from Container Nos.
1, 1A, and 2, less the acetone blank (see Figure 5G-4).
12.5 Particulate Concentration.
Where: K2 = 0.001 g/mg for metric units. =
0.0154 gr/mg for English units.
12.6 Particulate Emission Rate.
Note:
Particulate emission rate results produced using the sampling
train described in section 6 and shown in Figure 5G-1 shall be
adjusted for reporting purposes by the following method adjustment
factor:
Where: K3 = constant, 1.82 for metric units. =
constant, 0.643 for English units.
12.7 Proportional Rate Variation. Calculate PR for each
10-minute interval, i, of the test run.
Alternate calculation procedures for proportional rate variation
may be used if other sample flow rate data (e.g., orifice flow
meters or rotameters) are monitored to maintain proportional
sampling rates. The proportional rate variations shall be
calculated for each 10-minute interval by comparing the stack to
nozzle velocity ratio for each 10-minute interval to the average
stack to nozzle velocity ratio for the test run. Proportional rate
variation may be calculated for intervals shorter than 10 minutes
with appropriate revisions to Equation 5G-5. If no more than 10
percent of the PR values for all the intervals exceed 90 percent
≤PR ≤110 percent, and if no PR value for any interval exceeds 80
percent ≤PR ≤120 percent, the results are acceptable. If the PR
values for the test run are judged to be unacceptable, report the
test run emission results, but do not include the results in
calculating the weighted average emission rate, and repeat the test
run.
16.1 Method 5H Sampling Train. The sampling train and sample
collection, recovery, and analysis procedures described in Method
5H, sections 6.1.1, 7.1, 7.2, 8.1, 8.10, 8.11, and 11.0,
respectively, may be used in lieu of similar sections in Method 5G.
Operation of the Method 5H sampling train in the dilution tunnel is
as described in section 8.10 of this method. Filter temperatures
and condenser conditions are as described in Method 5H. No
adjustment to the measured particulate matter emission rate
(Equation 5G-4, section 12.6) is to be applied to the particulate
emission rate measured by this alternative method.
16.2 Dual Sampling Trains. Two sampling trains may be operated
simultaneously at sample flow rates other than that specified in
section 8.10, provided that the following specifications are
met.
16.2.1 Sampling Train. The sampling train configuration shall be
the same as specified in section 6.1.1, except the probe, filter,
and filter holder need not be the same sizes as specified in the
applicable sections. Filter holders of plastic materials such as
Nalgene or polycarbonate materials may be used (the Gelman 1119
filter holder has been found suitable for this purpose). With such
materials, it is recommended that solvents not be used in sample
recovery. The filter face velocity shall not exceed 150 mm/sec (30
ft/min) during the test run. The dry gas meter shall be calibrated
for the same flow rate range as encountered during the test runs.
Two separate, complete sampling trains are required for each test
run.
16.2.2 Probe Location. Locate the two probes in the dilution
tunnel at the same level (see section 6.1.4.3). Two sample ports
are necessary. Locate the probe inlets within the 50 mm (2 in.)
diameter centroidal area of the dilution tunnel no closer than 25
mm (1 in.) apart.
16.2.3 Sampling Train Operation. Operate the sampling trains as
specified in section 8.10, maintaining proportional sampling rates
and starting and stopping the two sampling trains simultaneously.
The pitot values as described in section 8.5.2 shall be used to
adjust sampling rates in both sampling trains.
16.2.4 Recovery and Analysis of Sample. Recover and analyze the
samples from the two sampling trains separately, as specified in
sections 8.12 and 11.0, respectively.
16.2.4.1 For this alternative procedure, the probe and filter
holder assembly may be weighed without sample recovery (use no
solvents) described above in order to determine the sample weight
gains. For this approach, weigh the clean, dry probe and filter
holder assembly upstream of the front filter (without filters) to
the nearest 0.1 mg to establish the tare weights. The filter holder
section between the front and second filter need not be weighed. At
the end of the test run, carefully clean the outside of the probe,
cap the ends, and identify the sample (label). Remove the filters
from the filter holder assemblies as described for container Nos. 1
and 1A in section 8.12.2.1. Reassemble the filter holder assembly,
cap the ends, identify the sample (label), and transfer all the
samples to the laboratory weighing area for final weighing.
Requirements for capping and transport of sample containers are not
applicable if sample recovery and analysis occur in the same
room.
16.2.4.2 For this alternative procedure, filters may be weighed
directly without a petri dish. If the probe and filter holder
assembly are to be weighed to determine the sample weight, rinse
the probe with acetone to remove moisture before desiccating prior
to the test run. Following the test run, transport the probe and
filter holder to the desiccator, and uncap the openings of the
probe and the filter holder assembly. Desiccate for 24 hours and
weigh to a constant weight. Report the results to the nearest 0.1
mg.
16.2.5 Calculations. Calculate an emission rate (Section 12.6)
for the sample from each sampling train separately and determine
the average emission rate for the two values. The two emission
rates shall not differ by more than 7.5 percent from the average
emission rate, or 7.5 percent of the weighted average emission rate
limit in the applicable subpart of the regulations, whichever is
greater. If this specification is not met, the results are
unacceptable. Report the results, but do not include the results in
calculating the weighted average emission rate. Repeat the test run
until acceptable results are achieved, report the average emission
rate for the acceptable test run, and use the average in
calculating the weighted average emission rate.
17.0 References
Same as Method 5, section 17.0, References 1 through 11, with
the addition of the following:
1. Oregon Department of Environmental Quality. Standard Method
for Measuring the Emissions and Efficiencies of Woodstoves. June 8,
1984. Pursuant to Oregon Administrative Rules Chapter 340, Division
21.
2. American Society for Testing and Materials. Proposed Test
Methods for Heating Performance and Emissions of Residential
Wood-fired Closed Combustion-Chamber Heating Appliances. E-6
Proposal P 180. August 1986.
18.0 Tables, Diagrams, Flowcharts, and Validation Data Method 5H -
Determination of Particulate Matter Emissions From Wood Heaters
From a Stack Location Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 2, Method 3, Method 5, Method 5G,
Method 6, Method 6C, Method 16A, and Method 28.
1.0 Scope and Application
1.1 Analyte. Particulate matter (PM). No CAS number
assigned.
1.2 Applicability. This method is applicable for the
determination of PM and condensible emissions from wood
heaters.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 Particulate matter is withdrawn proportionally from the wood
heater exhaust and is collected on two glass fiber filters
separated by impingers immersed in an ice water bath. The first
filter is maintained at a temperature of no greater than 120 °C
(248 °F). The second filter and the impinger system are cooled such
that the temperature of the gas exiting the second filter is no
greater than 20 °C (68 °F). The particulate mass collected in the
probe, on the filters, and in the impingers is determined
gravimetrically after the removal of uncombined water.
3.0 Definitions
Same as in Method 6C, section 3.0.
4.0 Interferences [Reserved] 5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies
6.1 Sample Collection. The following items are required for
sample collection:
6.1.1 Sampling Train. The sampling train configuration is shown
in Figure 5H-1. Same as Method 5, section 6.1.1, with the exception
of the following:
6.1.1.1 Probe Nozzle. The nozzle is optional; a straight
sampling probe without a nozzle is an acceptable alternative.
6.1.1.2 Probe Liner. Same as Method 5, section 6.1.1.2, except
that the maximum length of the sample probe shall be 0.6 m (2 ft)
and probe heating is optional.
6.1.1.3 Filter Holders. Two each of borosilicate glass, with a
glass frit or stainless steel filter support and a silicone rubber,
Teflon, or Viton gasket. The holder design shall provide a positive
seal against leakage from the outside or around the filter. The
front filter holder shall be attached immediately at the outlet of
the probe and prior to the first impinger. The second filter holder
shall be attached on the outlet of the third impinger and prior to
the inlet of the fourth (silica gel) impinger.
6.1.2 Barometer. Same as Method 5, section 6.2.
6.1.3 Stack Gas Flow Rate Measurement System. A schematic of an
example test system is shown in Figure 5H-2. The flow rate
measurement system consists of the following components:
6.1.3.1 Sample Probe. A glass or stainless steel sampling
probe.
6.1.3.2 Gas Conditioning System. A high density filter to remove
particulate matter and a condenser capable of lowering the dew
point of the gas to less than 5 °C (40 °F). Desiccant, such as
Drierite, may be used to dry the sample gas. Do not use silica
gel.
6.1.3.3 Pump. An inert (e.g., Teflon or stainless steel
heads) sampling pump capable of delivering more than the total
amount of sample required in the manufacturer's instructions for
the individual instruments. A means of controlling the analyzer
flow rate and a device for determining proper sample flow rate
(e.g., precision rotameter, pressure gauge downstream of all
flow controls) shall be provided at the analyzer. The requirements
for measuring and controlling the analyzer flow rate are not
applicable if data are presented that demonstrate that the analyzer
is insensitive to flow variations over the range encountered during
the test.
6.1.3.4 Carbon Monoxide (CO) Analyzer. Any analyzer capable of
providing a measure of CO in the range of 0 to 10 percent by volume
at least once every 10 minutes.
6.1.3.5 Carbon Dioxide (CO2) Analyzer. Any analyzer capable of
providing a measure of CO2 in the range of 0 to 25 percent by
volume at least once every 10 minutes.
Note:
Analyzers with ranges less than those specified above may be
used provided actual concentrations do not exceed the range of the
analyzer.
6.1.3.6 Manifold. A sampling tube capable of delivering the
sample gas to two analyzers and handling an excess of the total
amount used by the analyzers. The excess gas is exhausted through a
separate port.
6.1.3.7 Recorders (optional). To provide a permanent record of
the analyzer outputs.
6.1.4 Proportional Gas Flow Rate System. To monitor stack flow
rate changes and provide a measurement that can be used to adjust
and maintain particulate sampling flow rates proportional to the
stack gas flow rate. A schematic of the proportional flow rate
system is shown in Figure 5H-2 and consists of the following
components:
6.1.4.1 Tracer Gas Injection System. To inject a known
concentration of sulfur dioxide (SO2) into the flue. The tracer gas
injection system consists of a cylinder of SO2, a gas cylinder
regulator, a stainless steel needle valve or flow controller, a
nonreactive (stainless steel and glass) rotameter, and an injection
loop to disperse the SO2 evenly in the flue.
6.1.4.2 Sample Probe. A glass or stainless steel sampling
probe.
6.1.4.3 Gas Conditioning System. A combustor as described in
Method 16A, sections 6.1.5 and 6.1.6, followed by a high density
filter to remove particulate matter, and a condenser capable of
lowering the dew point of the gas to less than 5 °C (40 °F).
Desiccant, such as Drierite, may be used to dry the sample gas. Do
not use silica gel.
6.1.4.4 Pump. Same as described in section 6.1.3.3.
6.1.4.5 SO2 Analyzer. Any analyzer capable of providing a
measure of the SO2 concentration in the range of 0 to 1,000 ppm by
volume (or other range necessary to measure the SO2 concentration)
at least once every 10 minutes.
6.1.4.6 Recorder (optional). To provide a permanent record of
the analyzer outputs.
Note:
Other tracer gas systems, including helium gas systems, are
acceptable for determination of instantaneous proportional sampling
rates.
6.2 Sample Recovery. Same as Method 5, section 6.2.
6.3 Sample Analysis. Same as Method 5, section 6.3, with the
addition of the following:
6.3.1 Separatory Funnel. Glass or Teflon, 500-ml or greater.
7.0 Reagents and Standards
7.1 Sample Collection. Same as Method 5, section 7.1, including
deionized distilled water.
7.2 Sample Recovery. Same as Method 5, section 7.2.
7.3 Sample Analysis. The following reagents and standards are
required for sample analysis:
7.3.4 Cylinder Gases. For the purposes of this procedure, span
value is defined as the upper limit of the range specified for each
analyzer as described in section 6.1.3.4 or 6.1.3.5. If an analyzer
with a range different from that specified in this method is used,
the span value shall be equal to the upper limit of the range for
the analyzer used (see note in section 6.1.3.5).
7.3.4.1 Calibration Gases. The calibration gases for the CO2,
CO, and SO2 analyzers shall be CO2 in nitrogen (N2), CO in N2, and
SO2 in N2, respectively. CO2 and CO calibration gases may be
combined in a single cylinder. Use three calibration gases as
specified in Method 6C, sections 7.2.1 through 7.2.3.
7.3.4.2 SO2 Injection Gas. A known concentration of SO2 in N2.
The concentration must be at least 2 percent SO2 with a maximum of
100 percent SO2.
8.0 Sample Collection, Preservation, Transport, and Storage
8.1 Pretest Preparation. Same as Method 5, section 8.1.
8.2 Calibration Gas and SO2 Injection Gas Concentration
Verification, Sampling System Bias Check, Response Time Test, and
Zero and Calibration Drift Tests. Same as Method 6C, sections
8.2.1, 8.2.3, 8.2.4, and 8.5, respectively, except that for
verification of CO and CO2 gas concentrations, substitute Method 3
for Method 6.
8.3 Preliminary Determinations.
8.3.1 Sampling Location. The sampling location for the
particulate sampling probe shall be 2.45 ±0.15 m (8 ±0.5 ft) above
the platform upon which the wood heater is placed (i.e., the
top of the scale).
8.3.2 Sampling Probe and Nozzle. Select a nozzle, if used, sized
for the range of velocity heads, such that it is not necessary to
change the nozzle size in order to maintain proportional sampling
rates. During the run, do not change the nozzle size. Select a
suitable probe liner and probe length to effect minimum
blockage.
8.4 Preparation of Particulate Sampling Train. Same as Method 5,
section 8.3, with the exception of the following:
8.4.1 The train should be assembled as shown in Figure 5H-1.
8.4.2 A glass cyclone may not be used between the probe and
filter holder.
8.5 Leak-Check Procedures.
8.5.1 Leak-Check of Metering System Shown in Figure 5H-1. That
portion of the sampling train from the pump to the orifice meter
shall be leak-checked after each certification or audit test. Use
the procedure described in Method 5, section 8.4.1.
8.5.2 Pretest Leak-Check. A pretest leak-check of the sampling
train is recommended, but not required. If the pretest leak-check
is conducted, the procedures outlined in Method 5, section 8.5.2
should be used. A vacuum of 130 mm Hg (5 in. Hg) may be used
instead of 380 mm Hg (15 in. Hg).
8.5.2 Leak-Checks During Sample Run. If, during the sampling
run, a component (e.g., filter assembly or impinger) change
becomes necessary, conduct a leak-check as described in Method 5,
section 8.4.3.
8.5.3 Post-Test Leak-Check. A leak-check is mandatory at the
conclusion of each sampling run. The leak-check shall be performed
in accordance with the procedures outlined in Method 5, section
8.4.4, except that a vacuum of 130 mm Hg (5 in. Hg) or the greatest
vacuum measured during the test run, whichever is greater, may be
used instead of 380 mm Hg (15 in. Hg).
8.6 Tracer Gas Procedure. A schematic of the tracer gas
injection and sampling systems is shown in Figure 5H-2.
8.6.1 SO2 Injection Probe. Install the SO2 injection probe and
dispersion loop in the stack at a location 2.9 ±0.15 m (9.5 ±0.5
ft) above the sampling platform.
8.6.2 SO2 Sampling Probe. Install the SO2 sampling probe at the
centroid of the stack at a location 4.1 ±0.15 m (13.5 ±0.5 ft)
above the sampling platform.
8.7 Flow Rate Measurement System. A schematic of the flow rate
measurement system is shown in Figure 5H-2. Locate the flow rate
measurement sampling probe at the centroid of the stack at a
location 2.3 ±0.3 m (7.5 ±1 ft) above the sampling platform.
8.8 Tracer Gas Procedure. Within 1 minute after closing the wood
heater door at the start of the test run (as defined in Method 28,
section 8.8.1), meter a known concentration of SO2 tracer gas at a
constant flow rate into the wood heater stack. Monitor the SO2
concentration in the stack, and record the SO2 concentrations at
10-minute intervals or more often. Adjust the particulate sampling
flow rate proportionally to the SO2 concentration changes using
Equation 5H-6 (e.g., the SO2 concentration at the first
10-minute reading is measured to be 100 ppm; the next 10 minute SO2
concentration is measured to be 75 ppm: the particulate sample flow
rate is adjusted from the initial 0.15 cfm to 0.20 cfm). A check
for proportional rate variation shall be made at the completion of
the test run using Equation 5H-10.
8.9 Volumetric Flow Rate Procedure. Apply stoichiometric
relationships to the wood combustion process in determining the
exhaust gas flow rate as follows:
8.9.1 Test Fuel Charge Weight. Record the test fuel charge
weight (wet) as specified in Method 28, section 8.8.2. The wood is
assumed to have the following weight percent composition: 51
percent carbon, 7.3 percent hydrogen, 41 percent oxygen. Record the
wood moisture for each fuel charge as described in Method 28,
section 8.6.5. The ash is assumed to have negligible effect on
associated C, H, and O concentrations after the test burn.
8.9.2 Measured Values. Record the CO and CO2 concentrations in
the stack on a dry basis every 10 minutes during the test run or
more often. Average these values for the test run. Use as a mole
fraction (e.g., 10 percent CO2 is recorded as 0.10) in the
calculations to express total flow (see Equation 5H-6).
8.10 Sampling Train Operation.
8.10.1 For each run, record the data required on a data sheet
such as the one shown in Figure 5H-3. Be sure to record the initial
dry gas meter reading. Record the dry gas meter readings at the
beginning and end of each sampling time increment, when changes in
flow rates are made, before and after each leak-check, and when
sampling is halted. Take other readings as indicated on Figure 5H-3
at least once each 10 minutes during the test run.
8.10.2 Remove the nozzle cap, verify that the filter and probe
heating systems are up to temperature, and that the probe is
properly positioned. Position the nozzle, if used, facing into gas
stream, or the probe tip in the 50 mm (2 in.) centroidal area of
the stack.
8.10.3 Be careful not to bump the probe tip into the stack wall
when removing or inserting the probe through the porthole; this
minimizes the chance of extracting deposited material.
8.10.4 When the probe is in position, block off the openings
around the probe and porthole to prevent unrepresentative dilution
of the gas stream.
8.10.5 Begin sampling at the start of the test run as defined in
Method 28, section 8.8.1, start the sample pump, and adjust the
sample flow rate to between 0.003 and 0.014 m 3/min (0.1 and 0.5
cfm). Adjust the sample flow rate proportionally to the stack gas
flow during the test run according to the procedures outlined in
section 8. Maintain a proportional sampling rate (within 10 percent
of the desired value) and a filter holder temperature no greater
than 120 °C (248 °F).
8.10.6 During the test run, make periodic adjustments to keep
the temperature around the filter holder at the proper level. Add
more ice to the impinger box and, if necessary, salt to maintain a
temperature of less than 20 °C (68 °F) at the condenser/silica gel
outlet.
8.10.7 If the pressure drop across the filter becomes too high,
making proportional sampling difficult to maintain, either filter
may be replaced during a sample run. It is recommended that another
complete filter assembly be used rather than attempting to change
the filter itself. Before a new filter assembly is installed,
conduct a leak-check (see section 8.5.2). The total particulate
weight shall include the summation of all filter assembly catches.
The total time for changing sample train components shall not
exceed 10 minutes. No more than one component change is allowed for
any test run.
8.10.8 At the end of the test run, turn off the coarse adjust
valve, remove the probe and nozzle from the stack, turn off the
pump, record the final dry gas meter reading, and conduct a
post-test leak-check, as outlined in section 8.5.3.
8.11 Sample Recovery. Same as Method 5, section 8.7, with the
exception of the following:
8.11.1 Blanks. The volume of the acetone blank may be about
50-ml, rather than 200-ml; a 200-ml water blank shall also be saved
for analysis.
8.11.2 Samples.
8.11.2.1 Container Nos. 1 and 1A. Treat the two filters
according to the procedures outlined in Method 5, section 8.7.6.1.
The filters may be stored either in a single container or in
separate containers.
8.11.2.2 Container No. 2. Same as Method 5, section 8.7.6.2,
except that the container should not be sealed until the impinger
rinse solution is added (see section 8.10.2.4).
8.11.2.3 Container No. 3. Treat the impingers as follows:
Measure the liquid which is in the first three impingers to within
1-ml by using a graduated cylinder or by weighing it to within 0.5
g by using a balance (if one is available). Record the volume or
weight of liquid present. This information is required to calculate
the moisture content of the effluent gas. Transfer the water from
the first, second, and third impingers to a glass container.
Tighten the lid on the sample container so that water will not leak
out.
8.11.2.4 Rinse impingers and graduated cylinder, if used, with
acetone three times or more. Avoid direct contact between the
acetone and any stopcock grease or collection of any stopcock
grease in the rinse solutions. Add these rinse solutions to sample
Container No. 2.
8.11.2.5 Container No. 4. Same as Method 5, section 8.7.6.3
8.12 Sample Transport. Whenever possible, containers should be
transferred in such a way that they remain upright at all
times.
Note:
Requirements for capping and transport of sample containers are
not applicable if sample recovery and analysis occur in the same
room.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
8.2
Sampling system bias
check
Ensures that bias introduced
by measurement system, minus analyzer, is no greater than 3 percent
of span.
8.2
Analyzer zero and calibration
drift tests
Ensures that bias introduced
by drift in the measurement system output during the run is no
greater than 3 percent of span.
8.5, 10.1,
12.13
Sampling equipment leak-check
and calibration; proportional sampling rate verification
Ensures accurate measurement
of stack gas flow rate, sample volume.
10.1
Analytical balance
calibration
Ensure accurate and precise
measurement of collected particulate.
10.3
Analyzer calibration error
check
Ensures that bias introduced
by analyzer calibration error is no greater than 2 percent of
span.
9.2 Volume Metering System Checks. Same as Method 5, section
9.2.
10.0 Calibration and Standardization Note:
Maintain a laboratory record of all calibrations.
10.1 Volume Metering System, Temperature Sensors, Barometer, and
Analytical Balance. Same as Method 5G, sections 10.2 through 10.5,
respectively.
10.2 SO2 Injection Rotameter. Calibrate the SO2 injection
rotameter system with a soap film flowmeter or similar direct
volume measuring device with an accuracy of 2 percent. Operate the
rotameter at a single reading for at least three calibration runs
for 10 minutes each. When three consecutive calibration flow rates
agree within 5 percent, average the three flow rates, mark the
rotameter at the calibrated setting, and use the calibration flow
rate as the SO2 injection flow rate during the test run. Repeat the
rotameter calibration before the first certification test and
semiannually thereafter.
10.3. Gas Analyzers. Same as Method 6C, section 10.0.
10.4 Field Balance Calibration Check. Check the calibration of
the balance used to weigh impingers with a weight that is at least
500g or within 50g of a loaded impinger. The weight must be ASTM
E617-13 “Standard Specification for Laboratory Weights and
Precision Mass Standards” (incorporated by reference - see 40 CFR
60.17) Class 6 (or better). Daily before use, the field balance
must measure the weight within ± 0.5g of the certified mass. If the
daily balance calibration check fails, perform corrective measures
and repeat the check before using balance.
10.5 Analytical Balance Calibration. Perform a multipoint
calibration (at least five points spanning the operational range)
of the analytical balance before the first use, and semiannually
thereafter. The calibration of the analytical balance must be
conducted using ASTM E617-13 “Standard Specification for Laboratory
Weights and Precision Mass Standards” (incorporated by reference -
see 40 CFR 60.17) Class 2 (or better) tolerance weights. Audit the
balance each day it is used for gravimetric measurements by
weighing at least one ASTM E617-13 Class 2 tolerance (or better)
calibration weight that corresponds to 50 to 150 percent of the
weight of one filter or between 1g and 5g. If the scale cannot
reproduce the value of the calibration weight to within 0.5 mg of
the certified mass, perform corrective measures, and conduct the
multipoint calibration before use.
11.0 Analytical Procedure
11.1 Record the data required on a sheet such as the one shown
in Figure 5H-4.
11.2 Handle each sample container as follows:
11.2.1 Container Nos. 1 and 1A. Treat the two filters according
to the procedures outlined in Method 5, section 11.2.1.
11.2.2 Container No. 2. Same as Method 5, section 11.2.2, except
that the beaker may be smaller than 250-ml.
11.2.3 Container No. 3. Note the level of liquid in the
container and confirm on the analysis sheet whether leakage
occurred during transport. If a noticeable amount of leakage has
occurred, either void the sample or use methods, subject to the
approval of the Administrator, to correct the final results.
Determination of sample leakage is not applicable if sample
recovery and analysis occur in the same room. Measure the liquid in
this container either volumetrically to within 1-ml or
gravimetrically to within 0.5 g. Transfer the contents to a 500-ml
or larger separatory funnel. Rinse the container with water, and
add to the separatory funnel. Add 25-ml of dichloromethane to the
separatory funnel, stopper and vigorously shake 1 minute, let
separate and transfer the dichloromethane (lower layer) into a
tared beaker or evaporating dish. Repeat twice more. It is
necessary to rinse Container No. 3 with dichloromethane. This rinse
is added to the impinger extract container. Transfer the remaining
water from the separatory funnel to a tared beaker or evaporating
dish and evaporate to dryness at 104 °C (220 °F). Desiccate and
weigh to a constant weight. Evaporate the combined impinger water
extracts at ambient temperature and pressure. Desiccate and weigh
to a constant weight. Report both results to the nearest 0.1
mg.
11.2.4 Container No. 4. Weigh the spent silica gel (or silica
gel plus impinger) to the nearest 0.5 g using a balance.
11.2.5 Acetone Blank Container. Same as Method 5, section
11.2.4, except that the beaker may be smaller than 250 ml.
11.2.6 Dichloromethane Blank Container. Treat the same as the
acetone blank.
11.2.7 Water Blank Container. Transfer the water to a tared 250
ml beaker and evaporate to dryness at 104 °C (220 °F). Desiccate
and weigh to a constant weight.
12.0 Data Analysis and Calculations
Carry out calculations, retaining at least one extra significant
figure beyond that of the acquired data. Round off figures after
the final calculation. Other forms of the equations may be used as
long as they give equivalent results.
12.1 Nomenclature.
A = Sample flow rate adjustment factor. BR = Dry wood burn rate,
kg/hr (lb/hr), from Method 28, Section 8.3. Bws = Water vapor in
the gas stream, proportion by volume. Ci = Tracer gas concentration
at inlet, ppmv. Co = Tracer gas concentration at outlet, ppmv. Cs =
Concentration of particulate matter in stack gas, dry basis,
corrected to standard conditions, g/dscm (g/dscf). E = Particulate
emission rate, g/hr (lb/hr). ΔH = Average pressure differential
across the orifice meter (see Figure 5H-1), mm H2O (in. H2O). La =
Maximum acceptable leakage rate for either a post-test leak-check
or for a leak-check following a component change; equal to 0.00057
cmm (0.020 cfm) or 4 percent of the average sampling rate,
whichever is less. L1 = Individual leakage rate observed during the
leak-check conducted before a component change, cmm (cfm). Lp =
Leakage rate observed during the post-test leak-check, cmm (cfm).
mn = Total amount of particulate matter collected, mg. Ma = Mass of
residue of solvent after evaporation, mg. NC = Grams of carbon/gram
of dry fuel (lb/lb), equal to 0.0425. NT = Total dry moles of
exhaust gas/kg of dry wood burned, g-moles/kg (lb-moles/lb). PR =
Percent of proportional sampling rate. Pbar = Barometric pressure
at the sampling site, mm Hg (in.Hg). Pstd = Standard absolute
pressure, 760 mm Hg (29.92 in.Hg). Qi = Gas volumetric flow rate at
inlet, cfm (l/min). Qo = Gas volumetric flow rate at outlet, cfm
(l/min).
12.2 Average Dry Gas Meter Temperature and Average Orifice
Pressure Drop. See data sheet (Figure 5H-3).
12.3 Dry Gas Volume. Same as Method 5, section 12.3.
12.4 Volume of Water Vapor.
Where: K2 = 0.001333 m 3/ml for metric units.
K2 = 0.04707 ft 3/ml for English units.
12.5 Moisture Content.
12.6 Solvent Wash Blank.
12.7 Total Particulate Weight. Determine the total particulate
catch from the sum of the weights obtained from containers 1, 2, 3,
and 4 less the appropriate solvent blanks (see Figure 5H-4).
Note:
Refer to Method 5, section 8.5 to assist in calculation of
results involving two filter assemblies.
12.8 Particulate Concentration.
12.9 Sample Flow Rate Adjustment.
12.10 Carbon Balance for Total Moles of Exhaust Gas (dry)/kg of
Wood Burned in the Exhaust Gas.
Where: K3 = 1000 g/kg for metric units. K3 =
1.0 lb/lb for English units. Note:
The NOX/SOX portion of the gas is assumed to be negligible.
12.11 Total Stack Gas Flow Rate.
Where: K4 = 0.02406 dscm/g-mole for metric
units. K4 = 384.8 dscf/lb-mole for English units.
12.12 Particulate Emission Rate.
12.13 Proportional Rate Variation. Calculate PR for each
10-minute interval, i, of the test run.
12.14 Acceptable Results. If no more than 15 percent of the PR
values for all the intervals fall outside the range 90 percent ≤PR
≤110 percent, and if no PR value for any interval falls outside the
range 75 ≤PR ≤125 percent, the results are acceptable. If the PR
values for the test runs are judged to be unacceptable, report the
test run emission results, but do not include the test run results
in calculating the weighted average emission rate, and repeat the
test.
12.15 Alternative Tracer Gas Flow Rate Determination.
Note:
This gives Q for a single instance only. Repeated multiple
determinations are needed to track temporal variations. Very small
variations in Qi, Ci, or Co may give very large variations in
Qo.
16.1 Alternative Stack Gas Volumetric Flow Rate Determination
(Tracer Gas).
16.1.1 Apparatus.
16.1.1.1 Tracer Gas Injector System. This is to inject a known
concentration of tracer gas into the stack. This system consists of
a cylinder of tracer gas, a gas cylinder regulator, a stainless
steel needle valve or a flow controller, a nonreactive (stainless
steel or glass) rotameter, and an injection loop to disperse the
tracer gas evenly in the stack.
16.1.1.2 Tracer Gas Probe. A glass or stainless steel sampling
probe.
16.1.1.3 Gas Conditioning System. A gas conditioning system is
suitable for delivering a cleaned sample to the analyzer consisting
of a filter to remove particulate and a condenser capable of
lowering the dew point of the sample gas to less than 5 °C (40 °F).
A desiccant such as anhydrous calcium sulfate may be used to dry
the sample gas. Desiccants which react or absorb tracer gas or
stack gas may not be used, e.g. silica gel absorbs CO2.
16.1.1.4 Pump. An inert (i.e., stainless steel or Teflon
head) pump to deliver more than the total sample required by the
manufacturer's specifications for the analyzer used to measure the
downstream tracer gas concentration.
16.1.1.5 Gas Analyzer. A gas analyzer is any analyzer capable of
measuring the tracer gas concentration in the range necessary at
least every 10 minutes. A means of controlling the analyzer flow
rate and a device for determining proper sample flow rate shall be
provided unless data is provided to show that the analyzer is
insensitive to flow variations over the range encountered during
the test. The gas analyzer needs to meet or exceed the following
performance specifications:
Linearity
±1 percent of full scale.
Calibration
Error
≤2 percent of span.
Response Time
≤10 seconds.
Zero Drift (24
hour)
≤2 percent of full scale.
Span Drift (24
hour)
≤2 percent of full scale.
Resolution
≤0.5 percent of span.
16.1.1.6 Recorder (optional). To provide a permanent record of
the analyzer output.
16.1.2 Reagents.
16.1.2.1 Tracer Gas. The tracer gas is sulfur hexafluoride in an
appropriate concentration for accurate analyzer measurement or pure
sulfur dioxide. The gas used must be nonreactive with the stack
effluent and give minimal (<3 percent) interference to
measurement by the gas analyzer.
16.1.3 Procedure. Select upstream and downstream locations in
the stack or duct for introducing the tracer gas and delivering the
sampled gas to the analyzer. The inlet location should be 8 or more
duct diameters beyond any upstream flow disturbance. The outlet
should be 8 or more undisturbed duct diameters from the inlet and 2
or more duct diameters from the duct exit. After installing the
apparatus, meter a known concentration of the tracer gas into the
stack at the inlet location. Use the gas sample probe and analyzer
to show that no stratification of the tracer gas is found in the
stack at the measurement locations. Monitor the tracer gas
concentration from the outlet location and record the concentration
at 10-minute intervals or more often at the option of the tester. A
minimum of three measured intervals is recommended to determine the
stack gas volumetric flow rate. Other statistical procedures may be
applied for complete flow characterization and additional
QA/QC.
17.0 References
Same as Method 5G, section 17.0.
18.0 Tables, Diagrams, Flowcharts, and Validation Data Method 5I -
Determination of Low Level Particulate Matter Emissions From
Stationary Sources Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Certain
information is contained in other EPA procedures found in this
part. Therefore, to obtain reliable results, persons using this
method should have experience with and a thorough knowledge of the
following Methods: Methods 1, 2, 3, 4 and 5.
1. Scope and Application.
1.1 Analyte. Particulate matter (PM). No CAS number
assigned.
1.2 Applicability. This method is applicable for the
determination of low level particulate matter (PM) emissions from
stationary sources. The method is most effective for total PM
catches of 50 mg or less. This method was initially developed for
performing correlation of manual PM measurements to PM continuous
emission monitoring systems (CEMS), however it is also useful for
other low particulate concentration applications.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods. Method 5I requires the use of paired
trains. Acceptance criteria for the identification of data quality
outliers from the paired trains are provided in section 12.2 of
this Method.
2. Summary of Method.
2.1. Description. The system setup and operation is essentially
identical to Method 5. Particulate is withdrawn isokinetically from
the source and collected on a 47 mm glass fiber filter maintained
at a temperature of 120 ±14 °C (248 ±25 °F). The PM mass is
determined by gravimetric analysis after the removal of uncombined
water. Specific measures in this procedure designed to improve
system performance at low particulate levels include:
1. Improved sample handling procedures 2 Light weight sample filter
assembly 3. Use of low residue grade acetone Accuracy is improved
through the minimization of systemic errors associated with sample
handling and weighing procedures. High purity reagents, all glass,
grease free, sample train components, and light weight filter
assemblies and beakers, each contribute to the overall objective of
improved precision and accuracy at low particulate concentrations.
2.2 Paired Trains. This method must be performed using a paired
train configuration. These trains may be operated as co-located
trains (to trains operating collecting from one port) or as
simultaneous trains (separate trains operating from different ports
at the same time). Procedures for calculating precision of the
paired trains are provided in section 12.
2.3 Detection Limit. a. Typical detection limit for manual
particulate testing is 0.5 mg. This mass is also cited as the
accepted weight variability limit in determination of “constant
weight” as cited in section 8.1.2 of this Method. EPA has performed
studies to provide guidance on minimum PM catch. The minimum
detection limit (MDL) is the minimum concentration or amount of an
analyte that can be determined with a specified degree of
confidence to be different from zero. We have defined the minimum
or target catch as a concentration or amount sufficiently larger
than the MDL to ensure that the results are reliable and
repeatable. The particulate matter catch is the product of the
average particulate matter concentration on a mass per volume basis
and the volume of gas collected by the sample train. The tester can
generally control the volume of gas collected by increasing the
sampling time or to a lesser extent by increasing the rate at which
sample is collected. If the tester has a reasonable estimate of the
PM concentration from the source, the tester can ensure that the
target catch is collected by sampling the appropriate gas
volume.
b. However, if the source has a very low particulate matter
concentration in the stack, the volume of gas sampled may need to
be very large which leads to unacceptably long sampling times. When
determining compliance with an emission limit, EPA guidance has
been that the tester does not always have to collect the target
catch. Instead, we have suggested that the tester sample enough
stack gas, that if the source were exactly at the level of the
emission standard, the sample catch would equal the target catch.
Thus, if at the end of the test the catch were smaller than the
target, we could still conclude that the source is in compliance
though we might not know the exact emission level. This volume of
gas becomes a target volume that can be translated into a target
sampling time by assuming an average sampling rate. Because the MDL
forms the basis for our guidance on target sampling times, EPA has
conducted a systematic laboratory study to define what is the MDL
for Method 5 and determined the Method to have a calculated
practical quantitation limit (PQL) of 3 mg of PM and an MDL of 1
mg.
c. Based on these results, the EPA has concluded that for PM
testing, the target catch must be no less than 3 mg. Those sample
catches between 1 mg and 3 mg are between the detection limit and
the limit of quantitation. If a tester uses the target catch to
estimate a target sampling time that results in sample catches that
are less than 3 mg, you should not automatically reject the
results. If the tester calculated the target sampling time as
described above by assuming that the source was at the level of the
emission limit, the results would still be valid for determining
that the source was in compliance. For purposes other than
determining compliance, results should be divided into two
categories - those that fall between 3 mg and 1 mg and those that
are below 1 mg. A sample catch between 1 and 3 mg may be used for
such purposes as calculating emission rates with the understanding
that the resulting emission rates can have a high degree of
uncertainty. Results of less than 1 mg should not be used for
calculating emission rates or pollutant concentrations.
d. When collecting small catches such as 3 mg, bias becomes an
important issue. Source testers must use extreme caution to reach
the PQL of 3 mg by assuring that sampling probes are very clean
(perhaps confirmed by low blank weights) before use in the field.
They should also use low tare weight sample containers, and
establish a well-controlled balance room to weigh the samples.
3. Definitions.
3.1 Light Weight Filter Housing. A smaller housing that
allows the entire filtering system to be weighed before and after
sample collection. (See. 6.1.3)
3.2 Paired Train. Sample systems trains may be operated
as co-located trains (two sample probes attached to each other in
the same port) or as simultaneous trains (two separate trains
operating from different ports at the same time).
4. Interferences.
a. There are numerous potential interferents that may be
encountered during performance of Method 5I sampling and analyses.
This Method should be considered more sensitive to the normal
interferents typically encountered during particulate testing
because of the low level concentrations of the flue gas stream
being sampled.
b. Care must be taken to minimize field contamination,
especially to the filter housing since the entire unit is weighed
(not just the filter media). Care must also be taken to ensure that
no sample is lost during the sampling process (such as during port
changes, removal of the filter assemblies from the probes,
etc.).
c. Balance room conditions are a source of concern for analysis
of the low level samples. Relative humidity, ambient temperatures
variations, air draft, vibrations and even barometric pressure can
affect consistent reproducible measurements of the sample media.
Ideally, the same analyst who performs the tare weights should
perform the final weights to minimize the effects of procedural
differences specific to the analysts.
d. Attention must also be provided to weighing artifacts caused
by electrostatic charges which may have to be discharged or
neutralized prior to sample analysis. Static charge can affect
consistent and reliable gravimetric readings in low humidity
environments. Method 5I recommends a relative humidity of less than
50 percent in the weighing room environment used for sample
analyses. However, lower humidity may be encountered or required to
address sample precision problems. Low humidity conditions can
increase the effects of static charge.
e. Other interferences associated with typical Method 5 testing
(sulfates, acid gases, etc.) are also applicable to Method 5I.
5. Safety.
Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety concerns associated with its use. It is the
responsibility of the user to establish appropriate safety and
health practices and to determine the applicability and observe all
regulatory limitations before using this method.
6. Equipment and Supplies.
6.1 Sample Collection Equipment and Supplies. The sample train
is nearly identical in configuration to the train depicted in
Figure 5-1 of Method 5. The primary difference in the sample trains
is the lightweight Method 5I filter assembly that attaches directly
to the exit to the probe. Other exceptions and additions specific
to Method 5I include:
6.1.1 Probe Nozzle. Same as Method 5, with the exception that it
must be constructed of borosilicate or quartz glass tubing.
6.1.2 Probe Liner. Same as Method 5, with the exception that it
must be constructed of borosilicate or quartz glass tubing.
6.1.3 Filter Holder. The filter holder is constructed of
borosilicate or quartz glass front cover designed to hold a 47-mm
glass fiber filter, with a wafer thin stainless steel (SS) filter
support, a silicone rubber or Viton O-ring, and Teflon tape seal.
This holder design will provide a positive seal against leakage
from the outside or around the filter. The filter holder assembly
fits into a SS filter holder and attaches directly to the outlet of
the probe. The tare weight of the filter, borosilicate or quartz
glass holder, SS filter support, O-ring and Teflon tape seal
generally will not exceed approximately 35 grams. The filter holder
is designed to use a 47-mm glass fiber filter meeting the quality
criteria in of Method 5. These units are commercially available
from several source testing equipment vendors. Once the filter
holder has been assembled, desiccated and tared, protect it from
external sources of contamination by covering the front socket with
a ground glass plug. Secure the plug with an impinger clamp or
other item that will ensure a leak-free fitting.
6.2 Sample Recovery Equipment and Supplies. Same as Method 5,
with the following exceptions:
6.2.1 Probe-Liner and Probe-Nozzle Brushes. Teflon or nylon
bristle brushes with stainless steel wire handles, should be used
to clean the probe. The probe brush must have extensions (at least
as long as the probe) of Teflon, nylon or similarly inert material.
The brushes must be properly sized and shaped for brushing out the
probe liner and nozzle.
6.2.2 Wash Bottles. Two Teflon wash bottles are recommended
however, polyethylene wash bottles may be used at the option of the
tester. Acetone should not be stored in polyethylene bottles for
longer than one month.
6.2.3 Filter Assembly Transport. A system should be employed to
minimize contamination of the filter assemblies during transport to
and from the field test location. A carrying case or packet with
clean compartments of sufficient size to accommodate each filter
assembly can be used. This system should have an air tight seal to
further minimize contamination during transport to and from the
field.
6.3 Analysis Equipment and Supplies. Same as Method 5, with the
following exception:
6.3.1 Lightweight Beaker Liner. Teflon or other lightweight
beaker liners are used for the analysis of the probe and nozzle
rinses. These light weight liners are used in place of the
borosilicate glass beakers typically used for the Method 5
weighings in order to improve sample analytical precision.
6.3.2 Anti-static Treatment. Commercially available gaseous
anti-static rinses are recommended for low humidity situations that
contribute to static charge problems.
7. Reagents and Standards.
7.1 Sampling Reagents. The reagents used in sampling are the
same as Method 5 with the following exceptions:
7.1.1 Filters. The quality specifications for the filters are
identical to those cited for Method 5. The only difference is the
filter diameter of 47 millimeters.
7.1.2 Stopcock Grease. Stopcock grease cannot be used with this
sampling train. We recommend that the sampling train be assembled
with glass joints containing O-ring seals or screw-on connectors,
or similar.
7.1.3 Acetone. Low residue type acetone, ≤0.001 percent residue,
purchased in glass bottles is used for the recovery of particulate
matter from the probe and nozzle. Acetone from metal containers
generally has a high residue blank and should not be used.
Sometimes, suppliers transfer acetone to glass bottles from metal
containers; thus, acetone blanks must be run prior to field use and
only acetone with low blank values (≤0.001 percent residue, as
specified by the manufacturer) must be used. Acetone blank
correction is not allowed for this method; therefore, it is
critical that high purity reagents be purchased and verified prior
to use.
7.1.4 Gloves. Disposable, powder-free, latex surgical gloves, or
their equivalent are used at all times when handling the filter
housings or performing sample recovery.
7.2 Standards. There are no applicable standards commercially
available for Method 5I analyses.
8. Sample Collection, Preservation, Storage, and Transport.
8.1 Pretest Preparation. Same as Method 5 with several
exceptions specific to filter assembly and weighing.
8.1.1 Filter Assembly. Uniquely identify each filter support
before loading filters into the holder assembly. This can be done
with an engraving tool or a permanent marker. Use powder free latex
surgical gloves whenever handling the filter holder assemblies.
Place the O-ring on the back of the filter housing in the O-ring
groove. Place a 47 mm glass fiber filter on the O-ring with the
face down. Place a stainless steel filter holder against the back
of the filter. Carefully wrap 5 mm ( 1/4 inch) wide Teflon” tape
one timearound the outside of the filter holder overlapping the
stainless steel filter support by approximately 2.5 mm ( 1/8 inch).
Gently brush the Teflon tape down on the back of the stainless
steel filter support. Store the filter assemblies in their
transport case until time for weighing or field use.
8.1.2 Filter Weighing Procedures. a. Desiccate the entire filter
holder assemblies at 20 ±5.6 °C (68 ±10 °F) and ambient pressure
for at least 24 hours. Weigh at intervals of at least 6 hours to a
constant weight, i.e., 0.5 mg change from previous weighing.
Record the results to the nearest 0.1 mg. During each weighing, the
filter holder assemblies must not be exposed to the laboratory
atmosphere for a period greater than 2 minutes and a relative
humidity above 50 percent. Lower relative humidity may be required
in order to improve analytical precision. However, low humidity
conditions increase static charge to the sample media.
b. Alternatively (unless otherwise specified by the
Administrator), the filters holder assemblies may be oven dried at
105 °C (220 °F) for a minimum of 2 hours, desiccated for 2 hours,
and weighed. The procedure used for the tare weigh must also be
used for the final weight determination.
c. Experience has shown that weighing uncertainties are not only
related to the balance performance but to the entire weighing
procedure. Therefore, before performing any measurement, establish
and follow standard operating procedures, taking into account the
sampling equipment and filters to be used.
8.2 Preliminary Determinations. Select the sampling site,
traverse points, probe nozzle, and probe length as specified in
Method 5.
8.3 Preparation of Sampling Train. Same as Method 5, section
8.3, with the following exception: During preparation and assembly
of the sampling train, keep all openings where contamination can
occur covered until justbefore assembly or until sampling is about
to begin. Using gloves, place a labeled (identified) and weighed
filter holder assembly into the stainless steel holder. Then place
this whole unit in the Method 5 hot box, and attach it to the
probe. Do not use stopcock grease.
8.4 Leak-Check Procedures. Same as Method 5.
8.5 Sampling Train Operation.
8.5.1. Operation. Operate the sampling train in a manner
consistent with those described in Methods 1, 2, 4 and 5 in terms
of the number of sample points and minimum time per point. The
sample rate and total gas volume should be adjusted based on
estimated grain loading of the source being characterized. The
total sampling time must be a function of the estimated mass of
particulate to be collected for the run. Targeted mass to be
collected in a typical Method 5I sample train should be on the
order of 10 to 20 mg. Method 5I is most appropriate for total
collected masses of less than 50 milligrams, however, there is not
an exact particulate loading cutoff, and it is likely that some
runs may exceed 50 mg. Exceeding 50 mg (or less than 10 mg) for the
sample mass does not necessarily justify invalidating a sample run
if all other Method criteria are met.
8.5.2 Paired Train. This Method requires PM samples be collected
with paired trains.
8.5.2.1 It is important that the systems be operated truly
simultaneously. This implies that both sample systems start and
stop at the same times. This also means that if one sample system
is stopped during the run, the other sample systems must also be
stopped until the cause has been corrected.
8.5.2.2 Care should be taken to maintain the filter box
temperature of the paired trains as close as possible to the Method
required temperature of 120 ±14 °C (248 ±25 °F). If separate ovens
are being used for simultaneously operated trains, it is
recommended that the oven temperature of each train be maintained
within ±14 °C (±25 °F) of each other.
8.5.2.3 The nozzles for paired trains need not be identically
sized.
8.5.2.4 Co-located sample nozzles must be within the same plane
perpendicular to the gas flow. Co-located nozzles and pitot
assemblies should be within a 6.0 cm × 6.0 cm square (as cited for
a quadruple train in Reference Method 301).
8.5.3 Duplicate gas samples for molecular weight determination
need not be collected.
8.6 Sample Recovery. Same as Method 5 with several exceptions
specific to the filter housing.
8.6.1 Before moving the sampling train to the cleanup site,
remove the probe from the train and seal the nozzle inlet and
outlet of the probe. Be careful not to lose any condensate that
might be present. Cap the filter inlet using a standard ground
glass plug and secure the cap with an impinger clamp. Remove the
umbilical cord from the last impinger and cap the impinger. If a
flexible line is used between the first impinger condenser and the
filter holder, disconnect the line at the filter holder and let any
condensed water or liquid drain into the impingers or
condenser.
8.6.2 Transfer the probe and filter-impinger assembly to the
cleanup area. This area must be clean and protected from the wind
so that the possibility of losing any of the sample will be
minimized.
8.6.3 Inspect the train prior to and during disassembly and note
any abnormal conditions such as particulate color, filter loading,
impinger liquid color, etc.
8.6.4 Container No. 1, Filter Assembly. Carefully remove the
cooled filter holder assembly from the Method 5 hot box and place
it in the transport case. Use a pair of clean gloves to handle the
filter holder assembly.
8.6.5 Container No. 2, Probe Nozzle and Probe Liner Rinse. Rinse
the probe and nozzle components with acetone. Be certain that the
probe and nozzle brushes have been thoroughly rinsed prior to use
as they can be a source of contamination.
8.6.6 All Other Train Components. (Impingers) Same as Method
5.
8.7 Sample Storage and Transport. Whenever possible, containers
should be shipped in such a way that they remain upright at all
times. All appropriate dangerous goods shipping requirements must
be observed since acetone is a flammable liquid.
9. Quality Control.
9.1 Miscellaneous Field Quality Control Measures.
9.1.1 A quality control (QC) check of the volume metering system
at the field site is suggested before collecting the sample using
the procedures in Method 5, section 4.4.1.
9.1.2 All other quality control checks outlined in Methods 1, 2,
4 and 5 also apply to Method 5I. This includes procedures such as
leak-checks, equipment calibration checks, and independent checks
of field data sheets for reasonableness and completeness.
9.2 Quality Control Samples.
9.2.1 Required QC Sample. A laboratory reagent blank must be
collected and analyzed for each lot of acetone used for a field
program to confirm that it is of suitable purity. The particulate
samples cannot be blank corrected.
9.2.2 Recommended QC Samples. These samples may be collected and
archived for future analyses.
9.2.2.1 A field reagent blank is a recommended QC sample
collected from a portion of the acetone used for cleanup of the
probe and nozzle. Take 100 ml of this acetone directly from the
wash bottle being used and place it in a glass sample container
labeled “field acetone reagent blank.” At least one field reagent
blank is recommended for every five runs completed. The field
reagent blank samples demonstrate the purity of the acetone was
maintained throughout the program.
9.2.2.2 A field bias blank train is a recommended QC sample.
This sample is collected by recovering a probe and filter assembly
that has been assembled, taken to the sample location, leak
checked, heated, allowed to sit at the sample location for a
similar duration of time as a regular sample run, leak-checked
again, and then recovered in the same manner as a regular sample.
Field bias blanks are not a Method requirement, however, they are
recommended and are very useful for identifying sources of
contamination in emission testing samples. Field bias blank train
results greater than 5 times the method detection limit may be
considered problematic.
10. Calibration and Standardization Same as Method 5, section 5.
10.1 Field Balance Calibration Check. Check the calibration of
the balance used to weigh impingers with a weight that is at least
500g or within 50g of a loaded impinger. The weight must be ASTM
E617-13 “Standard Specification for Laboratory Weights and
Precision Mass Standards” (incorporated by reference - see 40 CFR
60.17) Class 6 (or better). Daily, before use, the field balance
must measure the weight within ±0.5g of the certified mass. If the
daily balance calibration check fails, perform corrective measures
and repeat the check before using balance.
10.2 Analytical Balance Calibration. Perform a multipoint
calibration (at least five points spanning the operational range)
of the analytical balance before the first use, and semiannually
thereafter. The calibration of the analytical balance must be
conducted using ASTM E617-13 “Standard Specification for Laboratory
Weights and Precision Mass Standards” (incorporated by reference -
see 40 CFR 60.17) Class 2 (or better) tolerance weights. Audit the
balance each day it is used for gravimetric measurements by
weighing at least one ASTM E617-13 Class 2 tolerance (or better)
calibration weight that corresponds to 50 to 150 percent of the
weight of one filter or between 1g and 5g. If the scale cannot
reproduce the value of the calibration weight to within 0.5 mg of
the certified mass, perform corrective measures and conduct the
multipoint calibration before use.
11. Analytical Procedures.
11.1 Analysis. Same as Method 5, sections 11.1-11.2.4, with the
following exceptions:
11.1.1 Container No. 1. Same as Method 5, section 11.2.1, with
the following exception: Use disposable gloves to remove each of
the filter holder assemblies from the desiccator, transport
container, or sample oven (after appropriate cooling).
11.1.2 Container No. 2. Same as Method 5, section 11.2.2, with
the following exception: It is recommended that the contents of
Container No. 2 be transferred to a 250 ml beaker with a Teflon
liner or similar container that has a minimal tare weight before
bringing to dryness.
12. Data Analysis and Calculations.
12.1 Particulate Emissions. The analytical results cannot be
blank corrected for residual acetone found in any of the blanks.
All other sample calculations are identical to Method 5.
12.2 Paired Trains Outliers. a. Outliers are identified through
the determination of precision and any systemic bias of the paired
trains. Data that do not meet this criteria should be flagged as a
data quality problem. The primary reason for performing dual train
sampling is to generate information to quantify the precision of
the Reference Method data. The relative standard deviation (RSD) of
paired data is the parameter used to quantify data precision. RSD
for two simultaneously gathered data points is determined according
to:
where, Ca
and Cb are concentration values determined from trains A and B
respectively. For RSD calculation, the concentration units are
unimportant so long as they are consistent.
b. A minimum precision criteria for Reference Method PM data is
that RSD for any data pair must be less than 10% as long as the
mean PM concentration is greater than 10 mg/dscm. If the mean PM
concentration is less than 10 mg/dscm higher RSD values are
acceptable. At mean PM concentration of 1 mg/dscm acceptable RSD
for paired trains is 25%. Between 1 and 10 mg/dscm acceptable RSD
criteria should be linearly scaled from 25% to 10%. Pairs of manual
method data exceeding these RSD criteria should be eliminated from
the data set used to develop a PM CEMS correlation or to assess
RCA. If the mean PM concentration is less than 1 mg/dscm, RSD does
not apply and the mean result is acceptable.
18. Tables, Diagrams, Flowcharts and Validation Data. Figure
5I-1 is a schematic of the sample train.
[36 FR
24877, Dec. 23, 1971] Editorial Note:For Federal Register citations
affecting appendix A-3 to part 60, see the List of CFR sections
Affected, which appears in the Finding Aids section of the printed
volume and at www.govinfo.gov.
Appendix A-4 to Part 60 - Test Methods 6 through 10B
40:9.0.1.1.1.0.1.1.4 : Appendix A
Appendix A-4 to Part 60 - Test Methods 6 through 10B Method 6 -
Determination of sulfur dioxide emissions from stationary sources
Method 6A - Determination of sulfur dioxide, moisture, and carbon
dioxide emissions from fossil fuel combustion sources Method 6B -
Determination of sulfur dioxide and carbon dioxide daily average
emissions from fossil fuel combustion sources Method 6C -
Determination of Sulfur Dioxide Emissions From Stationary Sources
(Instrumental Analyzer Procedure) Method 7 - Determination of
nitrogen oxide emissions from stationary sources Method 7A -
Determination of nitrogen oxide emissions from stationary sources -
Ion chromatographic method Method 7B - Determination of nitrogen
oxide emissions from stationary sources (Ultraviolet
spectrophotometry) Method 7C - Determination of nitrogen oxide
emissions from stationary sources -
Alkaline-permanganate/colorimetric method Method 7D - Determination
of nitrogen oxide emissions from stationary sources -
Alkaline-permanganate/ion chromatographic method Method 7E -
Determination of Nitrogen Oxides Emissions From Stationary Sources
(Instrumental Analyzer Procedure) Method 8 - Determination of
sulfuric acid mist and sulfur dioxide emissions from stationary
sources Method 9 - Visual determination of the opacity of emissions
from stationary sources Alternate method 1 - Determination of the
opacity of emissions from stationary sources remotely by lidar
Method 10 - Determination of carbon monoxide emissions from
stationary sources Method 10A - Determination of carbon monoxide
emissions in certifying continuous emission monitoring systems at
petroleum refineries Method 10B - Determination of carbon monoxide
emissions from stationary sources
The test methods in this appendix are referred to in § 60.8
(Performance Tests) and § 60.11 (Compliance With Standards and
Maintenance Requirements) of 40 CFR part 60, subpart A (General
Provisions). Specific uses of these test methods are described in
the standards of performance contained in the subparts, beginning
with Subpart D.
Within each standard of performance, a section title “Test
Methods and Procedures” is provided to: (1) Identify the test
methods to be used as reference methods to the facility subject to
the respective standard and (2) identify any special instructions
or conditions to be followed when applying a method to the
respective facility. Such instructions (for example, establish
sampling rates, volumes, or temperatures) are to be used either in
addition to, or as a substitute for procedures in a test method.
Similarly, for sources subject to emission monitoring requirements,
specific instructions pertaining to any use of a test method as a
reference method are provided in the subpart or in Appendix B.
Inclusion of methods in this appendix is not intended as an
endorsement or denial of their applicability to sources that are
not subject to standards of performance. The methods are
potentially applicable to other sources; however, applicability
should be confirmed by careful and appropriate evaluation of the
conditions prevalent at such sources.
The approach followed in the formulation of the test methods
involves specifications for equipment, procedures, and performance.
In concept, a performance specification approach would be
preferable in all methods because this allows the greatest
flexibility to the user. In practice, however, this approach is
impractical in most cases because performance specifications cannot
be established. Most of the methods described herein, therefore,
involve specific equipment specifications and procedures, and only
a few methods in this appendix rely on performance criteria.
Minor changes in the test methods should not necessarily affect
the validity of the results and it is recognized that alternative
and equivalent methods exist. section 60.8 provides authority for
the Administrator to specify or approve (1) equivalent methods, (2)
alternative methods, and (3) minor changes in the methodology of
the test methods. It should be clearly understood that unless
otherwise identified all such methods and changes must have prior
approval of the Administrator. An owner employing such methods or
deviations from the test methods without obtaining prior approval
does so at the risk of subsequent disapproval and retesting with
approved methods.
Within the test methods, certain specific equipment or
procedures are recognized as being acceptable or potentially
acceptable and are specifically identified in the methods. The
items identified as acceptable options may be used without approval
but must be identified in the test report. The potentially
approvable options are cited as “subject to the approval of the
Administrator” or as “or equivalent.” Such potentially approvable
techniques or alternatives may be used at the discretion of the
owner without prior approval. However, detailed descriptions for
applying these potentially approvable techniques or alternatives
are not provided in the test methods. Also, the potentially
approvable options are not necessarily acceptable in all
applications. Therefore, an owner electing to use such potentially
approvable techniques or alternatives is responsible for: (1)
assuring that the techniques or alternatives are in fact applicable
and are properly executed; (2) including a written description of
the alternative method in the test report (the written method must
be clear and must be capable of being performed without additional
instruction, and the degree of detail should be similar to the
detail contained in the test methods); and (3) providing any
rationale or supporting data necessary to show the validity of the
alternative in the particular application. Failure to meet these
requirements can result in the Administrator's disapproval of the
alternative.
Method 6 - Determination of Sulfur Dioxide Emissions From
Stationary Sources Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, Method 5,
and Method 8.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
SO2
7449-09-5
3.4 mg SO2/m 3
(2.12 × 10)−7 lb/ft 3
1.2 Applicability. This method applies to the measurement of
sulfur dioxide (SO2) emissions from stationary sources.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A gas sample is extracted from the sampling point in the
stack. The SO2 and the sulfur trioxide, including those fractions
in any sulfur acid mist, are separated. The SO2 fraction is
measured by the barium-thorin titration method.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Free Ammonia. Free ammonia interferes with this method by
reacting with SO2 to form particulate sulfite and by reacting with
the indicator. If free ammonia is present (this can be determined
by knowledge of the process and/or noticing white particulate
matter in the probe and isopropanol bubbler), alternative methods,
subject to the approval of the Administrator are required. One
approved alternative is listed in Reference 13 of section 17.0.
4.2 Water-Soluble Cations and Fluorides. The cations and
fluorides are removed by a glass wool filter and an isopropanol
bubbler; therefore, they do not affect the SO2 analysis. When
samples are collected from a gas stream with high concentrations of
metallic fumes (i.e., very fine cation aerosols) a
high-efficiency glass fiber filter must be used in place of the
glass wool plug (i.e., the one in the probe) to remove the
cation interferent.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user to establish appropriate safety and
health practices and determine the applicability of regulatory
limitations before performing this test method.
5.2 Corrosive reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water for at least 15 minutes. Remove
clothing under shower and decontaminate. Treat residual chemical
burns as thermal burns.
5.2.1 Hydrogen Peroxide (H2O2). Irritating to eyes, skin, nose,
and lungs. 30% H2O2 is a strong oxidizing agent. Avoid contact with
skin, eyes, and combustible material. Wear gloves when
handling.
5.2.2 Sodium Hydroxide (NaOH). Causes severe damage to eyes and
skin. Inhalation causes irritation to nose, throat, and lungs.
Reacts exothermically with limited amounts of water.
5.2.3 Sulfuric Acid (H2SO4). Rapidly destructive to body tissue.
Will cause third degree burns. Eye damage may result in blindness.
Inhalation may be fatal from spasm of the larynx, usually within 30
minutes. May cause lung tissue damage with edema. 1 mg/m 3 for 8
hours will cause lung damage or, in higher concentrations, death.
Provide ventilation to limit inhalation. Reacts violently with
metals and organics.
6.0 Equipment and Supplies
6.1 Sample Collection. The following items are required for
sample collection:
6.1.1 Sampling Train. A schematic of the sampling train is shown
in Figure 6-1. The sampling equipment described in Method 8 may be
substituted in place of the midget impinger equipment of Method 6.
However, the Method 8 train must be modified to include a heated
filter between the probe and isopropanol impinger, and the
operation of the sampling train and sample analysis must be at the
flow rates and solution volumes defined in Method 8. Alternatively,
SO2 may be determined simultaneously with particulate matter and
moisture determinations by either (1) replacing the water in a
Method 5 impinger system with a 3 percent H2O2 solution, or (2)
replacing the Method 5 water impinger system with a Method 8
isopropanol-filter-H2O2 system. The analysis for SO2 must be
consistent with the procedure of Method 8. The Method 6 sampling
train consists of the following components:
6.1.1.1 Probe. Borosilicate glass or stainless steel (other
materials of construction may be used, subject to the approval of
the Administrator), approximately 6 mm (0.25 in.) inside diameter,
with a heating system to prevent water condensation and a filter
(either in-stack or heated out-of-stack) to remove particulate
matter, including sulfuric acid mist. A plug of glass wool is a
satisfactory filter.
6.1.1.2 Bubbler and Impingers. One midget bubbler with
medium-coarse glass frit and borosilicate or quartz glass wool
packed in top (see Figure 6-1) to prevent sulfuric acid mist
carryover, and three 30-ml midget impingers. The midget bubbler and
midget impingers must be connected in series with leak-free glass
connectors. Silicone grease may be used, if necessary, to prevent
leakage. A midget impinger may be used in place of the midget
bubbler.
Note:
Other collection absorbers and flow rates may be used, subject
to the approval of the Administrator, but the collection efficiency
must be shown to be at least 99 percent for each test run and must
be documented in the report. If the efficiency is found to be
acceptable after a series of three tests, further documentation is
not required. To conduct the efficiency test, an extra absorber
must be added and analyzed separately. This extra absorber must not
contain more than 1 percent of the total SO2.
6.1.1.3 Glass Wool. Borosilicate or quartz.
6.1.1.4 Stopcock Grease. Acetone-insoluble, heat-stable silicone
grease may be used, if necessary.
6.1.1.5 Temperature Sensor. Dial thermometer, or equivalent, to
measure temperature of gas leaving impinger train to within 1 °C (2
°F).
6.1.1.6 Drying Tube. Tube packed with 6- to 16- mesh
indicating-type silica gel, or equivalent, to dry the gas sample
and to protect the meter and pump. If silica gel is previously
used, dry at 177 °C (350 °F) for 2 hours. New silica gel may be
used as received. Alternatively, other types of desiccants
(equivalent or better) may be used, subject to the approval of the
Administrator.
6.1.1.7 Valve. Needle valve, to regulate sample gas flow
rate.
6.1.1.8 Pump. Leak-free diaphragm pump, or equivalent, to pull
gas through the train. Install a small surge tank between the pump
and rate meter to negate the pulsation effect of the diaphragm pump
on the rate meter.
6.1.1.9 Rate Meter. Rotameter, or equivalent, capable of
measuring flow rate to within 2 percent of the selected flow rate
of about 1 liter/min (0.035 cfm).
6.1.1.10 Volume Meter. Dry gas meter (DGM), sufficiently
accurate to measure the sample volume to within 2 percent,
calibrated at the selected flow rate and conditions actually
encountered during sampling, and equipped with a temperature sensor
(dial thermometer, or equivalent) capable of measuring temperature
accurately to within 3 °C (5.4 °F). A critical orifice may be used
in place of the DGM specified in this section provided that it is
selected, calibrated, and used as specified in section 16.0.
6.1.2 Barometer. Mercury, aneroid, or other barometer capable of
measuring atmospheric pressure to within 2.5 mm Hg (0.1 in. Hg).
See the note in Method 5, section 6.1.2.
6.1.3 Vacuum Gauge and Rotameter. At least 760-mm Hg (30-in. Hg)
gauge and 0- to 40-ml/min rotameter, to be used for leak-check of
the sampling train.
6.2 Sample Recovery. The following items are needed for sample
recovery:
6.2.1 Wash Bottles. Two polyethylene or glass bottles,
500-ml.
6.2.2 Storage Bottles. Polyethylene bottles, 100-ml, to store
impinger samples (one per sample).
6.3 Sample Analysis. The following equipment is needed for
sample analysis:
6.3.1 Pipettes. Volumetric type, 5-ml, 20-ml (one needed per
sample), and 25-ml sizes.
6.3.2 Volumetric Flasks. 100-ml size (one per sample) and
1000-ml size.
6.3.3 Burettes. 5- and 50-ml sizes.
6.3.4 Erlenmeyer Flasks. 250-ml size (one for each sample,
blank, and standard).
6.3.5 Dropping Bottle. 125-ml size, to add indicator.
6.3.6 Graduated Cylinder. 100-ml size.
6.3.7 Spectrophotometer. To measure absorbance at 352 nm.
7.0 Reagents and Standards Note:
Unless otherwise indicated, all reagents must conform to the
specifications established by the Committee on Analytical Reagents
of the American Chemical Society. Where such specifications are not
available, use the best available grade.
7.1 Sample Collection. The following reagents are required for
sample collection:
7.1.1 Water. Deionized distilled to conform to ASTM
Specification D 1193-77 or 91 Type 3 (incorporated by reference -
see § 60.17). The KMnO4 test for oxidizable organic matter may be
omitted when high concentrations of organic matter are not expected
to be present.
7.1.2 Isopropanol, 80 Percent by Volume. Mix 80 ml of
isopropanol with 20 ml of water.
7.1.2.1 Check each lot of isopropanol for peroxide impurities as
follows: Shake 10 ml of isopropanol with 10 ml of freshly prepared
10 percent potassium iodide solution. Prepare a blank by similarly
treating 10 ml of water. After 1 minute, read the absorbance at 352
nm on a spectrophotometer using a 1-cm path length. If absorbance
exceeds 0.1, reject alcohol for use.
7.1.2.2 Peroxides may be removed from isopropanol by
redistilling or by passage through a column of activated alumina;
however, reagent grade isopropanol with suitably low peroxide
levels may be obtained from commercial sources. Rejection of
contaminated lots may, therefore, be a more efficient
procedure.
7.1.3 Hydrogen Peroxide (H2O2), 3 Percent by Volume. Add 10 ml
of 30 percent H2O2 to 90 ml of water. Prepare fresh daily.
7.1.4 Potassium Iodide Solution, 10 Percent Weight by Volume
(w/v). Dissolve 10.0 g of KI in water, and dilute to 100 ml.
Prepare when needed.
7.2 Sample Recovery. The following reagents are required for
sample recovery:
7.2.1 Water. Same as in section 7.1.1.
7.2.2 Isopropanol, 80 Percent by Volume. Same as in section
7.1.2.
7.3 Sample Analysis. The following reagents and standards are
required for sample analysis:
7.3.1 Water. Same as in section 7.1.1.
7.3.2 Isopropanol, 100 Percent.
7.3.3 Thorin Indicator.
1-(o-arsonophenylazo)-2-naphthol-3,6-disulfonic acid, disodium
salt, or equivalent. Dissolve 0.20 g in 100 ml of water.
7.3.4 Barium Standard Solution, 0.0100 N. Dissolve 1.95 g of
barium perchlorate trihydrate [Ba(ClO4)2 3H2O] in 200 ml water, and
dilute to 1 liter with isopropanol. Alternatively, 1.22 g of barium
chloride dihydrate [BaCl2 2H2O] may be used instead of the barium
perchlorate trihydrate. Standardize as in section 10.5.
7.3.5 Sulfuric Acid Standard, 0.0100 N. Purchase or standardize
to ±0.0002 N against 0.0100 N NaOH which has previously been
standardized against potassium acid phthalate (primary standard
grade).
8.0 Sample Collection, Preservation, Storage and Transport
8.1 Preparation of Sampling Train. Measure 15 ml of 80 percent
isopropanol into the midget bubbler and 15 ml of 3 percent H2O2
into each of the first two midget impingers. Leave the final midget
impinger dry. Assemble the train as shown in Figure 6-1. Adjust the
probe heater to a temperature sufficient to prevent water
condensation. Place crushed ice and water around the impingers.
8.2 Sampling Train Leak-Check Procedure. A leak-check prior to
the sampling run is recommended, but not required. A leak-check
after the sampling run is mandatory. The leak-check procedure is as
follows:
8.2.1 Temporarily attach a suitable (e.g., 0- to 40-
ml/min) rotameter to the outlet of the DGM, and place a vacuum
gauge at or near the probe inlet. Plug the probe inlet, pull a
vacuum of at least 250 mm Hg (10 in. Hg), and note the flow rate as
indicated by the rotameter. A leakage rate in excess of 2 percent
of the average sampling rate is not acceptable.
Note:
Carefully (i.e., slowly) release the probe inlet plug
before turning off the pump.
8.2.2 It is suggested (not mandatory) that the pump be
leak-checked separately, either prior to or after the sampling run.
To leak-check the pump, proceed as follows: Disconnect the drying
tube from the probe-impinger assembly. Place a vacuum gauge at the
inlet to either the drying tube or the pump, pull a vacuum of 250
mm Hg (10 in. Hg), plug or pinch off the outlet of the flow meter,
and then turn off the pump. The vacuum should remain stable for at
least 30 seconds.
If performed prior to the sampling run, the pump leak-check
shall precede the leak-check of the sampling train described
immediately above; if performed after the sampling run, the pump
leak-check shall follow the sampling train leak-check.
8.2.3 Other leak-check procedures may be used, subject to the
approval of the Administrator.
8.3 Sample Collection.
8.3.1 Record the initial DGM reading and barometric pressure. To
begin sampling, position the tip of the probe at the sampling
point, connect the probe to the bubbler, and start the pump. Adjust
the sample flow to a constant rate of approximately 1.0 liter/min
as indicated by the rate meter. Maintain this constant rate (±10
percent) during the entire sampling run.
8.3.2 Take readings (DGM volume, temperatures at DGM and at
impinger outlet, and rate meter flow rate) at least every 5
minutes. Add more ice during the run to keep the temperature of the
gases leaving the last impinger at 20 °C (68 °F) or less.
8.3.3 At the conclusion of each run, turn off the pump, remove
the probe from the stack, and record the final readings. Conduct a
leak-check as described in section 8.2. (This leak-check is
mandatory.) If a leak is detected, void the test run or use
procedures acceptable to the Administrator to adjust the sample
volume for the leakage.
8.3.4 Drain the ice bath, and purge the remaining part of the
train by drawing clean ambient air through the system for 15
minutes at the sampling rate. Clean ambient air can be provided by
passing air through a charcoal filter or through an extra midget
impinger containing 15 ml of 3 percent H2O2. Alternatively, ambient
air without purification may be used.
8.4 Sample Recovery. Disconnect the impingers after purging.
Discard the contents of the midget bubbler. Pour the contents of
the midget impingers into a leak-free polyethylene bottle for
shipment. Rinse the three midget impingers and the connecting tubes
with water, and add the rinse to the same storage container. Mark
the fluid level. Seal and identify the sample container.
9.0 Quality Control
Section
Quality control measure
Effect
7.1.2
Isopropanol check
Ensure acceptable level of
peroxide impurities in isopropanol.
8.2,
10.1-10.4
Sampling equipment leak-check
and calibration
Ensure accurate measurement of
stack gas flow rate, sample volume.
10.5
Barium standard solution
standardization
Ensure precision of normality
determination
11.2.3
Replicate titrations
Ensure precision of titration
determinations.
10.0 Calibration and Standardization
10.1 Volume Metering System.
10.1.1 Initial Calibration.
10.1.1.1 Before its initial use in the field, leak-check the
metering system (drying tube, needle valve, pump, rate meter, and
DGM) as follows: Place a vacuum gauge at the inlet to the drying
tube and pull a vacuum of 250 mm Hg (10 in. Hg). Plug or pinch off
the outlet of the flow meter, and then turn off the pump. The
vacuum must remain stable for at least 30 seconds. Carefully
release the vacuum gauge before releasing the flow meter end.
10.1.1.2 Remove the drying tube, and calibrate the metering
system (at the sampling flow rate specified by the method) as
follows: Connect an appropriately sized wet-test meter
(e.g., 1 liter per revolution) to the inlet of the needle
valve. Make three independent calibration runs, using at least five
revolutions of the DGM per run. Calculate the calibration factor Y
(wet-test meter calibration volume divided by the DGM volume, both
volumes adjusted to the same reference temperature and pressure)
for each run, and average the results (Yi). If any Y-value deviates
by more than 2 percent from (Yi), the metering system is
unacceptable for use. If the metering system is acceptable, use
(Yi) as the calibration factor for subsequent test runs.
10.1.2 Post-Test Calibration Check. After each field test
series, conduct a calibration check using the procedures outlined
in section 10.1.1.2, except that three or more revolutions of the
DGM may be used, and only two independent runs need be made. If the
average of the two post-test calibration factors does not deviate
by more than 5 percent from Yi, then Yi is accepted as the DGM
calibration factor (Y), which is used in Equation 6-1 to calculate
collected sample volume (see section 12.2). If the deviation is
more than 5 percent, recalibrate the metering system as in section
10.1.1, and determine a post-test calibration factor (Yf). Compare
Yi and Yf; the smaller of the two factors is accepted as the DGM
calibration factor. If recalibration indicates that the metering
system is unacceptable for use, either void the test run or use
methods, subject to the approval of the Administrator, to determine
an acceptable value for the collected sample volume.
10.1.3 DGM as a Calibration Standard. A DGM may be used as a
calibration standard for volume measurements in place of the
wet-test meter specified in section 10.1.1.2, provided that it is
calibrated initially and recalibrated periodically according to the
same procedures outlined in Method 5, section 10.3 with the
following exceptions: (a) the DGM is calibrated against a wet-test
meter having a capacity of 1 liter/rev (0.035 ft 3/rev) or 3
liters/rev (0.1 ft 3/rev) and having the capability of measuring
volume to within 1 percent; (b) the DGM is calibrated at 1
liter/min (0.035 cfm); and (c) the meter box of the Method 6
sampling train is calibrated at the same flow rate.
10.2 Temperature Sensors. Calibrate against mercury-in-glass
thermometers. An alternative mercury-free thermometer may be used
if the thermometer is, at a minimum, equivalent in terms of
performance or suitably effective for the specific temperature
measurement application.
10.3 Rate Meter. The rate meter need not be calibrated, but
should be cleaned and maintained according to the manufacturer's
instructions.
10.4 Barometer. Calibrate against a mercury barometer or
NIST-traceable barometer prior to the field test.
10.5 Barium Standard Solution. Standardize the barium
perchlorate or chloride solution against 25 ml of standard sulfuric
acid to which 100 ml of 100 percent isopropanol has been added. Run
duplicate analyses. Calculate the normality using the average of
duplicate analyses where the titrations agree within 1 percent or
0.2 ml, whichever is larger.
11.0 Analytical Procedure
11.1 Sample Loss Check. Note level of liquid in container and
confirm whether any sample was lost during shipment; note this
finding on the analytical data sheet. If a noticeable amount of
leakage has occurred, either void the sample or use methods,
subject to the approval of the Administrator, to correct the final
results.
11.2 Sample Analysis.
11.2.1 Transfer the contents of the storage container to a
100-ml volumetric flask, dilute to exactly 100 ml with water, and
mix the diluted sample.
11.2.2 Pipette a 20-ml aliquot of the diluted sample into a
250-ml Erlenmeyer flask and add 80 ml of 100 percent isopropanol
plus two to four drops of thorin indicator. While stirring the
solution, titrate to a pink endpoint using 0.0100 N barium standard
solution.
11.2.3 Repeat the procedures in section 11.2.2, and average the
titration volumes. Run a blank with each series of samples.
Replicate titrations must agree within 1 percent or 0.2 ml,
whichever is larger.
Note:
Protect the 0.0100 N barium standard solution from evaporation
at all times.
12.0 Data Analysis and Calculations
Carry out calculations, retaining at least one extra significant
figure beyond that of the acquired data. Round off figures after
final calculation.
12.1 Nomenclature CSO2 = Concentration of SO2, dry basis, corrected
to standard conditions, mg/dscm (lb/dscf). N = Normality of barium
standard titrant, meq/ml. Pbar = Barometric pressure, mm Hg (in.
Hg). Pstd = Standard absolute pressure, 760 mm Hg (29.92 in. Hg).
Tm = Average DGM absolute temperature, °K (°R). Tstd = Standard
absolute temperature, 293 °K (528 °R). Va = Volume of sample
aliquot titrated, ml. Vm = Dry gas volume as measured by the DGM,
dcm (dcf). Vm(std) = Dry gas volume measured by the DGM, corrected
to standard conditions, dscm (dscf). Vsoln = Total volume of
solution in which the SO2 sample is contained, 100 ml. Vt = Volume
of barium standard titrant used for the sample (average of
replicate titration), ml. Vtb = Volume of barium standard titrant
used for the blank, ml. Y = DGM calibration factor.
12.2 Dry Sample Gas Volume, Corrected to Standard
Conditions.
Where: K1 = 0.3855 °K/mm Hg for metric units,
K1 = 17.65 °R/in. Hg for English units.
12.3 SO2 Concentration.
Where: K2 = 32.03 mg SO2/meq for metric units,
K2 = 7.061 × 10−5 lb SO2/meq for English units. 13.0 Method
Performance
13.1 Range. The minimum detectable limit of the method has been
determined to be 3.4 mg SO2/m 3 (2.12 × 10−7 lb/ft 3). Although no
upper limit has been established, tests have shown that
concentrations as high as 80,000 mg/m 3 (0.005 lb/ft 3) of SO2 can
be collected efficiently at a rate of 1.0 liter/min (0.035 cfm) for
20 minutes in two midget impingers, each containing 15 ml of 3
percent H2O2. Based on theoretical calculations, the upper
concentration limit in a 20 liter (0.7 ft 3) sample is about 93,300
mg/m 3 (0.00583 lb/ft 3).
16.1 Nomenclature. Same as section 12.1, with the following
additions:
Bwa = Water vapor in ambient air, proportion by volume. Ma =
Molecular weight of the ambient air saturated at impinger
temperature, g/g-mole (lb/lb-mole). Ms = Molecular weight of the
sample gas saturated at impinger temperature, g/g-mole
(lb/lb-mole). Pc = Inlet vacuum reading obtained during the
calibration run, mm Hg (in. Hg). Psr = Inlet vacuum reading
obtained during the sampling run, mm Hg (in. Hg). Q std =
Volumetric flow rate through critical orifice, scm/min (scf/min).
Qstd = Average flow rate of pre-test and post-test calibration
runs, scm/min (scf/min). Tamb = Ambient absolute temperature of
air, °K (°R). Vsb = Volume of gas as measured by the soap bubble
meter, m 3 (ft 3).
Vsb(std) = Volume of gas as measured by the soap bubble meter,
corrected to standard conditions, scm (scf).
θ = Soap bubble travel time, min. θs = Time, min.
16.2 Critical Orifices for Volume and Rate Measurements. A
critical orifice may be used in place of the DGM specified in
section 6.1.1.10, provided that it is selected, calibrated, and
used as follows:
16.2.1 Preparation of Sampling Train. Assemble the sampling
train as shown in Figure 6-2. The rate meter and surge tank are
optional but are recommended in order to detect changes in the flow
rate.
Note:
The critical orifices can be adapted to a Method 6 type sampling
train as follows: Insert sleeve type, serum bottle stoppers into
two reducing unions. Insert the needle into the stoppers as shown
in Figure 6-3.
16.2.2 Selection of Critical Orifices.
16.2.2.1 The procedure that follows describes the use of
hypodermic needles and stainless steel needle tubings, which have
been found suitable for use as critical orifices. Other materials
and critical orifice designs may be used provided the orifices act
as true critical orifices, (i.e., a critical vacuum can be
obtained) as described in this section. Select a critical orifice
that is sized to operate at the desired flow rate. The needle sizes
and tubing lengths shown in Table 6-1 give the following
approximate flow rates.
16.2.2.2 Determine the suitability and the appropriate operating
vacuum of the critical orifice as follows: If applicable,
temporarily attach a rate meter and surge tank to the outlet of the
sampling train, if said equipment is not present (see section
16.2.1). Turn on the pump and adjust the valve to give an outlet
vacuum reading corresponding to about half of the atmospheric
pressure. Observe the rate meter reading. Slowly increase the
vacuum until a stable reading is obtained on the rate meter. Record
the critical vacuum, which is the outlet vacuum when the rate meter
first reaches a stable value. Orifices that do not reach a critical
value must not be used.
16.2.3 Field Procedures.
16.2.3.1 Leak-Check Procedure. A leak-check before the sampling
run is recommended, but not required. The leak-check procedure is
as follows: Temporarily attach a suitable (e.g., 0-40
ml/min) rotameter and surge tank, or a soap bubble meter and surge
tank to the outlet of the pump. Plug the probe inlet, pull an
outlet vacuum of at least 250 mm Hg (10 in. Hg), and note the flow
rate as indicated by the rotameter or bubble meter. A leakage rate
in excess of 2 percent of the average sampling rate (Q std) is not
acceptable. Carefully release the probe inlet plug before turning
off the pump.
16.2.3.2 Moisture Determination. At the sampling location, prior
to testing, determine the percent moisture of the ambient air using
the wet and dry bulb temperatures or, if appropriate, a relative
humidity meter.
16.2.3.3 Critical Orifice Calibration. At the sampling location,
prior to testing, calibrate the entire sampling train (i.e.,
determine the flow rate of the sampling train when operated at
critical conditions). Attach a 500-ml soap bubble meter to the
inlet of the probe, and operate the sampling train at an outlet
vacuum of 25 to 50 mm Hg (1 to 2 in. Hg) above the critical vacuum.
Record the information listed in Figure 6-4. Calculate the standard
volume of air measured by the soap bubble meter and the volumetric
flow rate using the equations below:
16.2.3.4 Sampling.
16.2.3.4.1 Operate the sampling train for sample collection at
the same vacuum used during the calibration run. Start the watch
and pump simultaneously. Take readings (temperature, rate meter,
inlet vacuum, and outlet vacuum) at least every 5 minutes. At the
end of the sampling run, stop the watch and pump
simultaneously.
16.2.3.4.2 Conduct a post-test calibration run using the
calibration procedure outlined in section 16.2.3.3. If the Qstd
obtained before and after the test differ by more than 5 percent,
void the test run; if not, calculate the volume of the gas measured
with the critical orifice using Equation 6-6 as follows:
16.2.3.4.3 If the percent difference between the molecular
weight of the ambient air at saturated conditions and the sample
gas is more that ±3 percent, then the molecular weight of the gas
sample must be considered in the calculations using the following
equation:
Note:
A post-test leak-check is not necessary because the post-test
calibration run results will indicate whether there is any
leakage.
16.2.3.4.4 Drain the ice bath, and purge the sampling train
using the procedure described in section 8.3.4.
16.3 Elimination of Ammonia Interference. The following
alternative procedures must be used in addition to those specified
in the method when sampling at sources having ammonia
emissions.
16.3.1 Sampling. The probe shall be maintained at 275 °C (527
°F) and equipped with a high-efficiency in-stack filter (glass
fiber) to remove particulate matter. The filter material shall be
unreactive to SO2. Whatman 934AH (formerly Reeve Angel 934AH)
filters treated as described in Reference 10 in section 17.0 of
Method 5 is an example of a filter that has been shown to work.
Where alkaline particulate matter and condensed moisture are
present in the gas stream, the filter shall be heated above the
moisture dew point but below 225 °C (437 °F).
16.3.2 Sample Recovery. Recover the sample according to section
8.4 except for discarding the contents of the midget bubbler. Add
the bubbler contents, including the rinsings of the bubbler with
water, to a separate polyethylene bottle from the rest of the
sample. Under normal testing conditions where sulfur trioxide will
not be present significantly, the tester may opt to delete the
midget bubbler from the sampling train. If an approximation of the
sulfur trioxide concentration is desired, transfer the contents of
the midget bubbler to a separate polyethylene bottle.
16.3.3 Sample Analysis. Follow the procedures in sections 11.1
and 11.2, except add 0.5 ml of 0.1 N HCl to the Erlenmeyer flask
and mix before adding the indicator. The following analysis
procedure may be used for an approximation of the sulfur trioxide
concentration. The accuracy of the calculated concentration will
depend upon the ammonia to SO2 ratio and the level of oxygen
present in the gas stream. A fraction of the SO2 will be counted as
sulfur trioxide as the ammonia to SO2 ratio and the sample oxygen
content increases. Generally, when this ratio is 1 or less and the
oxygen content is in the range of 5 percent, less than 10 percent
of the SO2 will be counted as sulfur trioxide. Analyze the peroxide
and isopropanol sample portions separately. Analyze the peroxide
portion as described above. Sulfur trioxide is determined by
difference using sequential titration of the isopropanol portion of
the sample. Transfer the contents of the isopropanol storage
container to a 100-ml volumetric flask, and dilute to exactly 100
ml with water. Pipette a 20-ml aliquot of this solution into a
250-ml Erlenmeyer flask, add 0.5 ml of 0.1 N HCl, 80 ml of 100
percent isopropanol, and two to four drops of thorin indicator.
Titrate to a pink endpoint using 0.0100 N barium perchlorate.
Repeat and average the titration volumes that agree within 1
percent or 0.2 ml, whichever is larger. Use this volume in Equation
6-2 to determine the sulfur trioxide concentration. From the flask
containing the remainder of the isopropanol sample, determine the
fraction of SO2 collected in the bubbler by pipetting 20-ml
aliquots into 250-ml Erlenmeyer flasks. Add 5 ml of 3 percent H2O2,
100 ml of 100 percent isopropanol, and two to four drips of thorin
indicator, and titrate as before. From this titration volume,
subtract the titrant volume determined for sulfur trioxide, and add
the titrant volume determined for the peroxide portion. This final
volume constitutes Vt, the volume of barium perchlorate used for
the SO2 sample.
17.0 References
1. Atmospheric Emissions from Sulfuric Acid Manufacturing
Processes. U.S. DHEW, PHS, Division of Air Pollution. Public Health
Service Publication No. 999-AP-13. Cincinnati, OH. 1965.
2. Corbett, P.F. The Determination of SO2 and SO3 in Flue Gases.
Journal of the Institute of Fuel. 24:237-243. 1961.
3. Matty, R.E., and E.K. Diehl. Measuring Flue-Gas SO2 and SO3.
Power. 101:94-97. November 1957.
4. Patton, W.F., and J.A. Brink, Jr. New Equipment and
Techniques for Sampling Chemical Process Gases. J. Air Pollution
Control Association. 13:162. 1963.
5. Rom, J.J. Maintenance, Calibration, and Operation of
Isokinetic Source Sampling Equipment. Office of Air Programs, U.S.
Environmental Protection Agency. Research Triangle Park, NC.
APTD-0576. March 1972.
6. Hamil, H.F., and D.E. Camann. Collaborative Study of Method
for the Determination of Sulfur Dioxide Emissions from Stationary
Sources (Fossil-Fuel Fired Steam Generators). U.S. Environmental
Protection Agency, Research Triangle Park, NC. EPA-650/4-74-024.
December 1973.
7. Annual Book of ASTM Standards. Part 31; Water, Atmospheric
Analysis. American Society for Testing and Materials. Philadelphia,
PA. 1974. pp. 40-42.
8. Knoll, J.E., and M.R. Midgett. The Application of EPA Method
6 to High Sulfur Dioxide Concentrations. U.S. Environmental
Protection Agency. Research Triangle Park, NC. EPA-600/4-76-038.
July 1976.
9. Westlin, P.R., and R.T. Shigehara. Procedure for Calibrating
and Using Dry Gas Volume Meters as Calibration Standards. Source
Evaluation Society Newsletter. 3(1):17-30. February
1978.
10. Yu, K.K. Evaluation of Moisture Effect on Dry Gas Meter
Calibration. Source Evaluation Society Newsletter.
5(1):24-28. February 1980.
11. Lodge, J.P., Jr., et al. The Use of Hypodermic
Needles as Critical Orifices in Air Sampling. J. Air Pollution
Control Association. 16:197-200. 1966.
12. Shigehara, R.T., and C.B. Sorrell. Using Critical Orifices
as Method 5 CalibrationStandards. Source Evaluation Society
Newsletter. 10:4-15. August 1985.
13. Curtis, F., Analysis of Method 6 Samples in the Presence of
Ammonia. Source Evaluation Society Newsletter. 13(1):9-15 February
1988.
18.0 Tables, Diagrams, Flowcharts and Validation Data
Table 6-1 - Approximate Flow Rates for
Various Needle Sizes
Needle size
(gauge)
Needle length
(cm)
Flow rate
(ml/min)
21
7.6
1,100
22
2.9
1,000
22
3.8
900
23
3.8
500
23
5.1
450
24
3.2
400
Method 6A - Determination of Sulfur Dioxide,
Moisture, and Carbon Dioxide From Fossil Fuel Combustion Sources
Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, Method 5,
Method 6, and Method 19.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
SO2
7449-09-05
3.4 mg SO2/m 3
(2.12 × 10−7 lb/ft 3)
CO2
124-38-9
N/A
H2O
7732-18-5
N/A
1.2 Applicability. This method is applicable for the
determination of sulfur dioxide (SO2) emissions from fossil fuel
combustion sources in terms of concentration (mg/dscm or lb/dscf)
and in terms of emission rate (ng/J or lb/10 6 Btu) and for the
determination of carbon dioxide (CO2) concentration (percent).
Moisture content (percent), if desired, may also be determined by
this method.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A gas sample is extracted from a sampling point in the
stack. The SO2 and the sulfur trioxide, including those fractions
in any sulfur acid mist, are separated. The SO2 fraction is
measured by the barium-thorin titration method. Moisture and CO2
fractions are collected in the same sampling train, and are
determined gravimetrically.
3.0 Definitions [Reserved] 4.0 Interferences
Same as Method 6, section 4.0.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user to establish appropriate safety and
health practices and determine the applicability of regulatory
limitations prior to performing this test method.
5.2 Corrosive reagents. Same as Method 6, section 5.2.
6.0 Equipment and Supplies
6.1 Sample Collection. Same as Method 6, section 6.1, with the
exception of the following:
6.1.1 Sampling Train. A schematic of the sampling train used in
this method is shown in Figure 6A-1.
6.1.1.1 Impingers and Bubblers. Two 30 = ml midget impingers
with a 1 = mm restricted tip and two 30 = ml midget bubblers with
unrestricted tips. Other types of impingers and bubblers
(e.g., Mae West for SO2 collection and rigid cylinders
containing Drierite for moisture absorbers), may be used with
proper attention to reagent volumes and levels, subject to the
approval of the Administrator.
6.1.1.2 CO2 Absorber. A sealable rigid cylinder or bottle with
an inside diameter between 30 and 90 mm , a length between 125 and
250 mm, and appropriate connections at both ends. The filter may be
a separate heated unit or may be within the heated portion of the
probe. If the filter is within the sampling probe, the filter
should not be within 15 cm of the probe inlet or any unheated
section of the probe, such as the connection to the first bubbler.
The probe and filter should be heated to at least 20 °C (68 °F)
above the source temperature, but not greater than 120 °C (248 °F).
The filter temperature (i.e., the sample gas temperature)
should be monitored to assure the desired temperature is
maintained. A heated Teflon connector may be used to connect the
filter holder or probe to the first impinger.
Note:
For applications downstream of wet scrubbers, a heated
out-of-stack filter (either borosilicate glass wool or glass fiber
mat) is necessary.
6.2 Sample Recovery. Same as Method 6, section 6.2.
6.3 Sample Analysis. Same as Method 6, section 6.3, with the
addition of a balance to measure within 0.05 g.
7.0 Reagents and Standards Note:
Unless otherwise indicated, all reagents must conform to the
specifications established by the Committee on Analytical Reagents
of the American Chemical Society. Where such specifications are not
available, use the best available grade.
7.1 Sample Collection. Same as Method 6, section 7.1, with the
addition of the following:
7.1.1 Drierite. Anhydrous calcium sulfate (CaSO4) desiccant, 8
mesh, indicating type is recommended.
Note:
Do not use silica gel or similar desiccant in this
application.
7.1.2 CO2 Absorbing Material. Ascarite II. Sodium
hydroxide-coated silica, 8- to 20-mesh.
7.2 Sample Recovery and Analysis. Same as Method 6, sections 7.2
and 7.3, respectively.
8.0 Sample Collection, Preservation, Transport, and Storage
8.1 Preparation of Sampling Train.
8.1.1 Measure 15 ml of 80 percent isopropanol into the first
midget bubbler and 15 ml of 3 percent hydrogen peroxide into each
of the two midget impingers (the second and third vessels in the
train) as described in Method 6, section 8.1. Insert the glass wool
into the top of the isopropanol bubbler as shown in Figure 6A-1.
Place about 25 g of Drierite into the second midget bubbler (the
fourth vessel in the train). Clean the outside of the bubblers and
impingers and allow the vessels to reach room temperature. Weigh
the four vessels simultaneously to the nearest 0.1 g, and record
this initial weight (mwi).
8.1.2 With one end of the CO2 absorber sealed, place glass wool
into the cylinder to a depth of about 1 cm (0.5 in.). Place about
150 g of CO2 absorbing material in the cylinder on top of the glass
wool, and fill the remaining space in the cylinder with glass wool.
Assemble the cylinder as shown in figure 6A-2. With the cylinder in
a horizontal position, rotate it around the horizontal axis. The
CO2 absorbing material should remain in position during the
rotation, and no open spaces or channels should be formed. If
necessary, pack more glass wool into the cylinder to make the CO2
absorbing material stable. Clean the outside of the cylinder of
loose dirt and moisture and allow the cylinder to reach room
temperature. Weigh the cylinder to the nearest 0.1 g, and record
this initial weight (mai).
8.1.3 Assemble the train as shown in figure 6A-1. Adjust the
probe heater to a temperature sufficient to prevent condensation
(see note in section 6.1). Place crushed ice and water around the
impingers and bubblers. Mount the CO2 absorber outside the water
bath in a vertical flow position with the sample gas inlet at the
bottom. Flexible tubing (e.g., Tygon) may be used to connect
the last SO2 absorbing impinger to the moisture absorber and to
connect the moisture absorber to the CO2 absorber. A second,
smaller CO2 absorber containing Ascarite II may be added in-line
downstream of the primary CO2 absorber as a breakthrough indicator.
Ascarite II turns white when CO2 is absorbed.
8.2 Sampling Train Leak-Check Procedure and Sample Collection.
Same as Method 6, sections 8.2 and 8.3, respectively.
8.3 Sample Recovery.
8.3.1 Moisture Measurement. Disconnect the isopropanol bubbler,
the SO2 impingers, and the moisture absorber from the sample train.
Allow about 10 minutes for them to reach room temperature, clean
the outside of loose dirt and moisture, and weigh them
simultaneously in the same manner as in section 8.1. Record this
final weight (mwf).
8.3.2 Peroxide Solution. Discard the contents of the isopropanol
bubbler and pour the contents of the midget impingers into a
leak-free polyethylene bottle for shipping. Rinse the two midget
impingers and connecting tubes with water, and add the washing to
the same storage container.
8.3.3 CO2 Absorber. Allow the CO2 absorber to warm to room
temperature (about 10 minutes), clean the outside of loose dirt and
moisture, and weigh to the nearest 0.1 g in the same manner as in
section 8.1. Record this final weight (maf). Discard used Ascarite
II material.
9.0 Quality Control
Same as Method 6, section 9.0.
10.0 Calibration and Standardization
Same as Method 6, section 10.0.
11.0 Analytical Procedure
11.1 Sample Analysis. The sample analysis procedure for SO2 is
the same as that specified in Method 6, section 11.0.
12.0 Data Analysis and Calculations
Same as Method 6, section 12.0, with the addition of the
following:
12.1 Nomenclature.
Cw = Concentration of moisture, percent. CCO2 = Concentration of
CO2, dry basis, percent. ESO2 = Emission rate of SO2, ng/J (lb/10 6
Btu). FC = Carbon F-factor from Method 19 for the fuel burned,
dscm/J (dscf/10 6 Btu). mwi = Initial weight of impingers,
bubblers, and moisture absorber, g. mwf = Final weight of
impingers, bubblers, and moisture absorber, g. mai = Initial weight
of CO2 absorber, g. maf = Final weight of CO2 absorber, g. mSO2 =
Mass of SO2 collected, mg. VCO2(std) = Equivalent volume of CO2
collected at standard conditions, dscm (dscf). Vw(std) = Equivalent
volume of moisture collected at standard conditions, scm (scf).
12.2 CO2 Volume Collected, Corrected to Standard Conditions.
Where: K3 = Equivalent volume of gaseous CO2 at
standard conditions, 5.467 × 10−4 dscm/g (1.930 × 10−2 dscf/g).
12.3 Moisture Volume Collected, Corrected to Standard
Conditions.
Where: K4 = Equivalent volume of water vapor at
standard conditions, 1.336 × 10−3 scm/g (4.717 × 10−2 scf/g).
13.1 Range and Precision. The minimum detectable limit and the
upper limit for the measurement of SO2 are the same as for Method
6. For a 20-liter sample, this method has a precision of ±0.5
percent CO2 for concentrations between 2.5 and 25 percent CO2 and
±1.0 percent moisture for moisture concentrations greater than 5
percent.
If the only emission measurement desired is in terms of emission
rate of SO2 (ng/J or lb/10 6 Btu), an abbreviated procedure may be
used. The differences between the above procedure and the
abbreviated procedure are described below.
16.1 Sampling Train. The sampling train is the same as that
shown in Figure 6A-1 and as described in section 6.1, except that
the dry gas meter is not needed.
16.2 Preparation of the Sampling Train. Follow the same
procedure as in section 8.1, except do not weigh the isopropanol
bubbler, the SO2 absorbing impingers, or the moisture absorber.
16.3 Sampling Train Leak-Check Procedure and Sample Collection.
Leak-check and operate the sampling train as described in section
8.2, except that dry gas meter readings, barometric pressure, and
dry gas meter temperatures need not be recorded during
sampling.
16.4 Sample Recovery. Follow the procedure in section 8.3,
except do not weigh the isopropanol bubbler, the SO2 absorbing
impingers, or the moisture absorber.
16.5 Sample Analysis. Analysis of the peroxide solution is the
same as that described in section 11.1.
Same as Method 6, section 17.0, References 1 through 8, with the
addition of the following:
1. Stanley, Jon and P.R. Westlin. An Alternate Method for Stack
Gas Moisture Determination. Source Evaluation Society Newsletter.
3(4). November 1978.
2. Whittle, Richard N. and P.R. Westlin. Air Pollution Test
Report: Development and Evaluation of an Intermittent Integrated
SO2/CO2 Emission Sampling Procedure. Environmental Protection
Agency, Emission Standard and Engineering Division, Emission
Measurement Branch. Research Triangle Park, NC. December 1979. 14
pp.
18.0 Tables, Diagrams, Flowcharts, and Validation Data Method 6B -
Determination of Sulfur Dioxide and Carbon Dioxide Daily Average
Emissions From Fossil Fuel Combustion Sources Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, Method 5,
Method 6, and Method 6A.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Sulfur dioxide
(SO2)
7449-09-05
3.4 mg SO2/m 3
(2.12 × 10−7 lb/ft 3)
Carbon dioxide
(CO2)
124-38-9
N/A
1.2 Applicability. This method is applicable for the
determination of SO2 emissions from combustion sources in terms of
concentration (ng/dscm or lb/dscf) and emission rate (ng/J or lb/10
6 Btu), and for the determination of CO2 concentration (percent) on
a daily (24 hours) basis.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A gas sample is extracted from the sampling point in the
stack intermittently over a 24-hour or other specified time period.
The SO2 fraction is measured by the barium-thorin titration method.
Moisture and CO2 fractions are collected in the same sampling
train, and are determined gravimetrically.
3.0 Definitions [Reserved] 4.0 Interferences
Same as Method 6, section 4.0.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user to establish appropriate safety and
health practices and determine the applicability of regulatory
limitations prior to performing this test method.
5.2 Corrosive Reagents. Same as Method 6, section 5.2.
6.0 Equipment and Supplies
Same as Method 6A, section 6.0, with the following exceptions
and additions:
6.1 The isopropanol bubbler is not used. An empty bubbler for
the collection of liquid droplets, that does not allow direct
contact between the collected liquid and the gas sample, may be
included in the sampling train.
6.2 For intermittent operation, include an industrial
timer-switch designed to operate in the “on” position at least 2
minutes continuously and “off” the remaining period over a
repeating cycle. The cycle of operation is designated in the
applicable regulation. At a minimum, the sampling operation should
include at least 12, equal, evenly-spaced periods per 24 hours.
6.3 Stainless steel sampling probes, type 316, are not
recommended for use with Method 6B because of potential sample
contamination due to corrosion. Glass probes or other types of
stainless steel, e.g., Hasteloy or Carpenter 20, are
recommended for long-term use.
Note:
For applications downstream of wet scrubbers, a heated
out-of-stack filter (either borosilicate glass wool or glass fiber
mat) is necessary. Probe and filter heating systems capable of
maintaining a sample gas temperature of between 20 and 120 °C (68
and 248 °F) at the filter are also required in these cases. The
electric supply for these heating systems should be continuous and
separate from the timed operation of the sample pump.
7.0 Reagents and Standards
Same as Method 6A, section 7.0, with the following
exceptions:
7.1 Isopropanol is not used for sampling.
7.2 The hydrogen peroxide absorbing solution shall be diluted to
no less than 6 percent by volume, instead of 3 percent as specified
in Methods 6 and 6A.
7.3 If the Method 6B sampling train is to be operated in a low
sample flow condition (less than 100 ml/min or 0.21 ft 3/hr),
molecular sieve material may be substituted for Ascarite II as the
CO2 absorbing material. The recommended molecular sieve material is
Union Carbide 1/16 inch pellets, 5 A°, or equivalent. Molecular
sieve material need not be discarded following the sampling run,
provided that it is regenerated as per the manufacturer's
instruction. Use of molecular sieve material at flow rates higher
than 100 ml/min (0.21 ft 3/hr) may cause erroneous CO2 results.
8.0 Sample Collection, Preservation, Transport, and Storage
8.1 Preparation of Sampling Train. Same as Method 6A, section
8.1, with the addition of the following:
8.1.1 The sampling train is assembled as shown in Figure 6A-1 of
Method 6A, except that the isopropanol bubbler is not included.
8.1.2 Adjust the timer-switch to operate in the “on” position
from 2 to 4 minutes on a 2-hour repeating cycle or other cycle
specified in the applicable regulation. Other timer sequences may
be used with the restriction that the total sample volume collected
is between 25 and 60 liters (0.9 and 2.1 ft 3) for the amounts of
sampling reagents prescribed in this method.
8.1.3 Add cold water to the tank until the impingers and
bubblers are covered at least two-thirds of their length. The
impingers and bubbler tank must be covered and protected from
intense heat and direct sunlight. If freezing conditions exist, the
impinger solution and the water bath must be protected.
Note:
Sampling may be conducted continuously if a low flow-rate sample
pump [20 to 40 ml/min (0.04 to 0.08 ft 3/hr) for the reagent
volumes described in this method] is used. If sampling is
continuous, the timer-switch is not necessary. In addition, if the
sample pump is designed for constant rate sampling, the rate meter
may be deleted. The total gas volume collected should be between 25
and 60 liters (0.9 and 2.1 ft 3) for the amounts of sampling
reagents prescribed in this method.
8.2 Sampling Train Leak-Check Procedure. Same as Method 6,
section 8.2.
8.3 Sample Collection.
8.3.1 The probe and filter (either in-stack, out-of-stack, or
both) must be heated to a temperature sufficient to prevent water
condensation.
8.3.2 Record the initial dry gas meter reading. To begin
sampling, position the tip of the probe at the sampling point,
connect the probe to the first impinger (or filter), and start the
timer and the sample pump. Adjust the sample flow to a constant
rate of approximately 1.0 liter/min (0.035 cfm) as indicated by the
rotameter. Observe the operation of the timer, and determine that
it is operating as intended (i.e., the timer is in the “on”
position for the desired period, and the cycle repeats as
required).
8.3.3 One time between 9 a.m. and 11 a.m. during the 24-hour
sampling period, record the dry gas meter temperature (Tm) and the
barometric pressure (P(bar)).
8.3.4 At the conclusion of the run, turn off the timer and the
sample pump, remove the probe from the stack, and record the final
gas meter volume reading. Conduct a leak-check as described in
section 8.2. If a leak is found, void the test run or use
procedures acceptable to the Administrator to adjust the sample
volume for leakage. Repeat the steps in sections 8.3.1 to 8.3.4 for
successive runs.
8.4 Sample Recovery. The procedures for sample recovery
(moisture measurement, peroxide solution, and CO2 absorber) are the
same as those in Method 6A, section 8.3.
9.0 Quality Control
Same as Method 6, section 9.0., with the exception of the
isopropanol-check.
10.0 Calibration and Standardization
Same as Method 6, section 10.0, with the addition of the
following:
10.1 Periodic Calibration Check. After 30 days of operation of
the test train, conduct a calibration check according to the same
procedures as the post-test calibration check (Method 6, section
10.1.2). If the deviation between initial and periodic calibration
factors exceeds 5 percent, use the smaller of the two factors in
calculations for the preceding 30 days of data, but use the most
recent calibration factor for succeeding test runs.
11.0 Analytical Procedures
11.1 Sample Loss Check and Analysis. Same as Method 6, sections
11.1 and 11.2, respectively.
12.0 Data Analysis and Calculations
Same as Method 6A, section 12.0, except that Pbar and Tm
correspond to the values recorded in section 8.3.3 of this method.
The values are as follows:
Pbar = Initial barometric pressure for the test period, mm Hg. Tm =
Absolute meter temperature for the test period, °K. 13.0 Method
Performance
13.1 Range.
13.1.1 Sulfur Dioxide. Same as Method 6.
13.1.2 Carbon Dioxide. Not determined.
13.2 Repeatability and Reproducibility. EPA-sponsored
collaborative studies were undertaken to determine the magnitude of
repeatability and reproducibility achievable by qualified testers
following the procedures in this method. The results of the studies
evolve from 145 field tests including comparisons with Methods 3
and 6. For measurements of emission rates from wet, flue gas
desulfurization units in (ng/J), the repeatability
(intra-laboratory precision) is 8.0 percent and the reproducibility
(inter-laboratory precision) is 11.1 percent.
Same as Method 6A, section 16.0, except that the timer is needed
and is operated as outlined in this method.
17.0 References
Same as Method 6A, section 17.0, with the addition of the
following:
1. Butler, Frank E., et. al. The Collaborative Test of Method
6B: Twenty-Four-Hour Analysis of SO2 and CO2. JAPCA. Vol. 33, No.
10. October 1983.
18.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
Method 6C - Determination of Sulfur Dioxide Emissions From
Stationary Sources (Instrumental Analyzer Procedure) 1.0 Scope and
Application What is Method 6C?
Method 6C is a procedure for measuring sulfur dioxide (SO2) in
stationary source emissions using a continuous instrumental
analyzer. Quality assurance and quality control requirements are
included to assure that you, the tester, collect data of known
quality. You must document your adherence to these specific
requirements for equipment, supplies, sample collection and
analysis, calculations, and data analysis.
This method does not completely describe all equipment,
supplies, and sampling and analytical procedures you will need but
refers to other methods for some of the details. Therefore, to
obtain reliable results, you should also have a thorough knowledge
of these additional test methods which are found in appendix A to
this part:
(a) Method 1 - Sample and Velocity Traverses for Stationary
Sources.
(b) Method 4 - Determination of Moisture Content in Stack
Gases.
(c) Method 6 - Determination of Sulfur Dioxide Emissions from
Stationary Sources.
(d) Method 7E - Determination of Nitrogen Oxides Emissions from
Stationary Sources (Instrumental Analyzer Procedure).
1.1 Analytes. What does this method determine? This
method measures the concentration of sulfur dioxide.
Analyte
CAS No.
Sensitivity
SO2
7446-09-5
Typically <2% of
Calibration Span.
1.2 Applicability. When is this method required? The use
of Method 6C may be required by specific New Source Performance
Standards, Clean Air Marketing rules, State Implementation Plans,
and permits where SO2 concentrations in stationary source emissions
must be measured, either to determine compliance with an applicable
emission standard or to conduct performance testing of a continuous
emission monitoring system (CEMS). Other regulations may also
require the use of Method 6C.
1.3 Data Quality Objectives. How good must my collected data
be? Refer to section 1.3 of Method 7E.
2.0 Summary of Method
In this method, you continuously sample the effluent gas and
convey the sample to an analyzer that measures the concentration of
SO2. You must meet the performance requirements of this method to
validate your data.
3.0 Definitions
Refer to section 3.0 of Method 7E for the applicable
definitions.
4.0 Interferences
Refer to Section 4.0 of Method 7E.
5.0 Safety
Refer to section 5.0 of Method 7E.
6.0 Equipment and Supplies
Figure 7E-1 of Method 7E is a schematic diagram of an acceptable
measurement system.
6.1 What do I need for the measurement system? The
essential components of the measurement system are the same as
those in sections 6.1 and 6.2 of Method 7E, except that the SO2
analyzer described in section 6.2 of this method must be used
instead of the analyzer described in section 6.2 of Method 7E. You
must follow the noted specifications in section 6.1 of Method
7E.
6.2 What analyzer must I use? You may use an instrument
that uses an ultraviolet, non-dispersive infrared, fluorescence, or
other detection principle to continuously measure SO2 in the gas
stream and meets the performance specifications in section 13.0.
The low-range and dual-range analyzer provisions in sections
6.2.8.1 and 6.2.8.2 of Method 7E apply.
7.0 Reagents and Standards
7.1 Calibration Gas. What calibration gases do I need?
Refer to section 7.1 of Method 7E for the calibration gas
requirements. Example calibration gas mixtures are listed
below.
(a) SO2 in nitrogen (N2).
(b) SO2 in air.
(c) SO2 and CO2 in N2.
(d) SO2 andO2 in N2.
(e) SO2/CO2/O2 gas mixture in N2.
(f) CO2/NOX gas mixture in N2.
(g) CO2/SO2/NOX gas mixture in N2.
7.2 Interference Check. What additional reagents do I need
for the interference check? The test gases for the interference
check are listed in Table 7E-3 of Method 7E. For the alternative
interference check, you must use the reagents described in section
7.0 of Method 6.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Sampling Site and Sampling Points. You must follow
the procedures of section 8.1 of Method 7E.
8.2 Initial Measurement System Performance Tests. You
must follow the procedures in section 8.2 of Method 7E. If a
dilution-type measurement system is used, the special
considerations in section 8.3 of Method 7E also apply.
8.3 Interference Check. You must follow the procedures of
section 8.2.7 of Method 7E to conduct an interference check,
substituting SO2 for NOX as the method pollutant. For dilution-type
measurement systems, you must use the alternative interference
check procedure in section 16 and a co-located, unmodified Method 6
sampling train.
8.4 Sample Collection. You must follow the procedures of
section 8.4 of Method 7E.
8.5 Post-Run System Bias Check and Drift Assessment. You
must follow the procedures of section 8.5 of Method 7E.
9.0 Quality Control
Follow quality control procedures in section 9.0 of Method
7E.
10.0 Calibration and Standardization
Follow the procedures for calibration and standardization in
section 10.0 of Method 7E.
11.0 Analytical Procedures
Because sample collection and analysis are performed together
(see section 8), additional discussion of the analytical procedure
is not necessary.
12.0 Calculations and Data Analysis
You must follow the applicable procedures for calculations and
data analysis in section 12.0 of Method 7E as applicable,
substituting SO2 for NOX as appropriate.
13.0 Method Performance
13.1 The specifications for the applicable performance checks
are the same as in section 13.0 of Method 7E.
13.2 Alternative Interference Check. The results are
acceptable if the difference between the Method 6C result and the
modified Method 6 result is less than 7.0 percent of the Method 6
result for each of the three test runs. For the purposes of
comparison, the Method 6 and 6C results must be expressed in the
same units of measure.
16.1 Alternative Interference Check. You may perform an
alternative interference check consisting of at least three
comparison runs between Method 6C and Method 6. This check
validates the Method 6C results at each particular source category
(type of facility) where the check is performed. When testing under
conditions of low concentrations (<15 ppm), this alternative
interference check is not allowed.
Note:
The procedure described below applies to non-dilution sampling
systems only. If this alternative interference check is used for a
dilution sampling system, use a standard Method 6 sampling train
and extract the sample directly from the exhaust stream at points
collocated with the Method 6C sample probe.
a. Build the modified Method 6 sampling train (flow control
valve, two midget impingers containing 3 percent hydrogen peroxide,
and dry gas meter) shown in Figure 6C-1. Connect the sampling train
to the sample bypass discharge vent. Record the dry gas meter
reading before you begin sampling. Simultaneously collect modified
Method 6 and Method 6C samples. Open the flow control valve in the
modified Method 6 train as you begin to sample with Method 6C.
Adjust the Method 6 sampling rate to 1 liter per minute (.10
percent). The sampling time per run must be the same as for Method
6 plus twice the average measurement system response time. If your
modified Method 6 train does not include a pump, you risk biasing
the results high if you over-pressurize the midget impingers and
cause a leak. You can reduce this risk by cautiously increasing the
flow rate as sampling begins.
b. After completing a run, record the final dry gas meter
reading, meter temperature, and barometric pressure. Recover and
analyze the contents of the midget impingers using the procedures
in Method 6. Determine the average gas concentration reported by
Method 6C for the run.
17.0 References
1. “EPA Traceability Protocol for Assay and Certification of
Gaseous Calibration Standards” September 1997 as amended,
EPA-600/R-97/121
18.0 Tables, Diagrams, Flowcharts, and Validation Data Method 7 -
Determination of Nitrogen Oxide Emissions From Stationary Sources
Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1 and Method 5.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Nitrogen oxides
(NOX), as NO2, including:
Nitric oxide
(NO)
10102-43-9
Nitrogen
dioxide (NO2)
10102-44-0
2-400 mg/dscm
1.2 Applicability. This method is applicable for the measurement
of nitrogen oxides (NOX) emitted from stationary sources.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sample methods.
2.0 Summary of Method
A grab sample is collected in an evacuated flask containing a
dilute sulfuric acid-hydrogen peroxide absorbing solution, and the
nitrogen oxides, except nitrous oxide, are measured
colorimetrically using the phenoldisulfonic acid (PDS)
procedure.
3.0 Definitions [Reserved] 4.0 Interferences
Biased results have been observed when sampling under conditions
of high sulfur dioxide concentrations. At or above 2100 ppm SO2,
use five times the H2O2 concentration of the Method 7 absorbing
solution. Laboratory tests have shown that high concentrations of
SO2 (about 2100 ppm) cause low results in Method 7 and 7A.
Increasing the H2O2 concentration to five times the original
concentration eliminates this bias. However, when no SO2 is
present, increasing the concentration by five times results in a
low bias.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user to establish appropriate safety and
health practices and to determine the applicability of regulatory
limitations prior to performing this test method.
5.2 Corrosive Reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water for at least 15 minutes. Remove
clothing under shower and decontaminate. Treat residual chemical
burns as thermal burns.
5.2.1 Hydrogen Peroxide (H2O2). Irritating to eyes, skin, nose,
and lungs.
5.2.2 Phenoldisulfonic Acid. Irritating to eyes and skin.
5.2.3 Sodium Hydroxide (NaOH). Causes severe damage to eyes and
skin. Inhalation causes irritation to nose, throat, and lungs.
Reacts exothermically with limited amounts of water.
5.2.4 Sulfuric Acid (H2SO4). Rapidly destructive to body tissue.
Will cause third degree burns. Eye damage may result in blindness.
Inhalation may be fatal from spasm of the larynx, usually within 30
minutes. May cause lung tissue damage with edema. 1 mg/m 3 for 8
hours will cause lung damage or, in higher concentrations, death.
Provide ventilation to limit inhalation. Reacts violently with
metals and organics.
5.2.5 Phenol. Poisonous and caustic. Do not handle with bare
hands as it is absorbed through the skin.
6.0 Equipment and Supplies
6.1 Sample Collection. A schematic of the sampling train used in
performing this method is shown in Figure 7-1. Other grab sampling
systems or equipment, capable of measuring sample volume to within
2.0 percent and collecting a sufficient sample volume to allow
analytical reproducibility to within 5 percent, will be considered
acceptable alternatives, subject to the approval of the
Administrator. The following items are required for sample
collection:
6.1.1 Probe. Borosilicate glass tubing, sufficiently heated to
prevent water condensation and equipped with an in-stack or heated
out-of-stack filter to remove particulate matter (a plug of glass
wool is satisfactory for this purpose). Stainless steel or Teflon
tubing may also be used for the probe. Heating is not necessary if
the probe remains dry during the purging period.
6.1.2 Collection Flask. Two-liter borosilicate, round bottom
flask, with short neck and 24/40 standard taper opening, protected
against implosion or breakage.
6.1.3 Flask Valve. T-bore stopcock connected to a 24/40 standard
taper joint.
6.1.4 Temperature Gauge. Dial-type thermometer, or other
temperature gauge, capable of measuring 1 °C (2 °F) intervals from
−5 to 50 °C (23 to 122 °F).
6.1.5 Vacuum Line. Tubing capable of withstanding a vacuum of 75
mm (3 in.) Hg absolute pressure, with “T” connection and T-bore
stopcock.
6.1.6 Vacuum Gauge. U-tube manometer, 1 meter (39 in.), with 1
mm (0.04 in.) divisions, or other gauge capable of measuring
pressure to within 2.5 mm (0.10 in.) Hg.
6.1.7 Pump. Capable of evacuating the collection flask to a
pressure equal to or less than 75 mm (3 in.) Hg absolute.
6.1.8 Squeeze Bulb. One-way.
6.1.9 Volumetric Pipette. 25-ml.
6.1.10 Stopcock and Ground Joint Grease. A high-vacuum,
high-temperature chlorofluorocarbon grease is required. Halocarbon
25-5S has been found to be effective.
6.1.11 Barometer. Mercury, aneroid, or other barometer capable
of measuring atmospheric pressure to within 2.5 mm (0.1 in.) Hg.
See note in Method 5, section 6.1.2.
6.2 Sample Recovery. The following items are required for sample
recovery:
6.2.1 Graduated Cylinder. 50-ml with 1 ml divisions.
6.2.5 Test Paper for Indicating pH. To cover the pH range of 7
to 14.
6.3 Analysis. The following items are required for analysis:
6.3.1 Volumetric Pipettes. Two 1-ml, two 2-ml, one 3-ml, one
4-ml, two 10-ml, and one 25-ml for each sample and standard.
6.3.2 Porcelain Evaporating Dishes. 175- to 250-ml capacity with
lip for pouring, one for each sample and each standard. The Coors
No. 45006 (shallowform, 195-ml) has been found to be satisfactory.
Alternatively, polymethyl pentene beakers (Nalge No. 1203, 150-ml),
or glass beakers (150-ml) may be used. When glass beakers are used,
etching of the beakers may cause solid matter to be present in the
analytical step; the solids should be removed by filtration.
6.3.3 Steam Bath. Low-temperature ovens or thermostatically
controlled hot plates kept below 70 °C (160 °F) are acceptable
alternatives.
6.3.4 Dropping Pipette or Dropper. Three required.
6.3.5 Polyethylene Policeman. One for each sample and each
standard.
6.3.6 Graduated Cylinder. 100-ml with 1-ml divisions.
6.3.7 Volumetric Flasks. 50-ml (one for each sample and each
standard), 100-ml (one for each sample and each standard, and one
for the working standard KNO3 solution), and 1000-ml (one).
6.3.8 Spectrophotometer. To measure at 410 nm.
6.3.9 Graduated Pipette. 10-ml with 0.1-ml divisions.
6.3.10 Test Paper for Indicating pH. To cover the pH range of 7
to 14.
6.3.11 Analytical Balance. To measure to within 0.1 mg.
7.0 Reagents and Standards
Unless otherwise indicated, it is intended that all reagents
conform to the specifications established by the Committee on
Analytical Reagents of the American Chemical Society, where such
specifications are available; otherwise, use the best available
grade.
7.1 Sample Collection. The following reagents are required for
sampling:
7.1.1 Water. Deionized distilled to conform to ASTM D 1193-77 or
91 Type 3 (incorporated by reference - see § 60.17). The KMnO4 test
for oxidizable organic matter may be omitted when high
concentrations of organic matter are not expected to be
present.
7.1.2 Absorbing Solution. Cautiously add 2.8 ml concentrated
H2SO4 to a 1-liter flask partially filled with water. Mix well, and
add 6 ml of 3 percent hydrogen peroxide, freshly prepared from 30
percent hydrogen peroxide solution. Dilute to 1 liter of water and
mix well. The absorbing solution should be used within 1 week of
its preparation. Do not expose to extreme heat or direct
sunlight.
7.2 Sample Recovery. The following reagents are required for
sample recovery:
7.2.1 Water. Same as in 7.1.1.
7.2.2 Sodium Hydroxide, 1 N. Dissolve 40 g NaOH in water, and
dilute to 1 liter.
7.3 Analysis. The following reagents and standards are required
for analysis:
7.3.1 Water. Same as in 7.1.1.
7.3.2 Fuming Sulfuric Acid. 15 to 18 percent by weight free
sulfur trioxide. HANDLE WITH CAUTION.
7.3.5 Potassium Nitrate (KNO3). Dried at 105 to 110 °C (221 to
230 °F) for a minimum of 2 hours just prior to preparation of
standard solution.
7.3.6 Standard KNO3 Solution. Dissolve exactly 2.198 g of dried
KNO3 in water, and dilute to 1 liter with water in a 1000-ml
volumetric flask.
7.3.7 Working Standard KNO3 Solution. Dilute 10 ml of the
standard solution to 100 ml with water. One ml of the working
standard solution is equivalent to 100 µg nitrogen dioxide
(NO2).
7.3.8 Phenoldisulfonic Acid Solution. Dissolve 25 g of pure
white phenol solid in 150 ml concentrated sulfuric acid on a steam
bath. Cool, add 75 ml fuming sulfuric acid (15 to 18 percent by
weight free sulfur trioxide - HANDLE WITH CAUTION), and heat at 100
°C (212 °F) for 2 hours. Store in a dark, stoppered bottle.
7.3.9 Concentrated Ammonium Hydroxide.
8.0 Sample Collection, Preservation, Storage and Transport
8.1 Sample Collection.
8.1.1 Flask Volume. The volume of the collection flask and flask
valve combination must be known prior to sampling. Assemble the
flask and flask valve, and fill with water to the stopcock. Measure
the volume of water to ±10 ml. Record this volume on the flask.
8.1.2 Pipette 25 ml of absorbing solution into a sample flask,
retaining a sufficient quantity for use in preparing the
calibration standards. Insert the flask valve stopper into the
flask with the valve in the “purge” position. Assemble the sampling
train as shown in Figure 7-1, and place the probe at the sampling
point. Make sure that all fittings are tight and leak-free, and
that all ground glass joints have been greased properly with a
high-vacuum, high temperature chlorofluorocarbon-based stopcock
grease. Turn the flask valve and the pump valve to their “evacuate”
positions. Evacuate the flask to 75 mm (3 in.) Hg absolute
pressure, or less. Evacuation to a pressure approaching the vapor
pressure of water at the existing temperature is desirable. Turn
the pump valve to its “vent” position, and turn off the pump. Check
for leakage by observing the manometer for any pressure
fluctuation. (Any variation greater than 10 mm (0.4 in.) Hg over a
period of 1 minute is not acceptable, and the flask is not to be
used until the leakage problem is corrected. Pressure in the flask
is not to exceed 75 mm (3 in.) Hg absolute at the time sampling is
commenced.) Record the volume of the flask and valve (Vf), the
flask temperature (Ti), and the barometric pressure. Turn the flask
valve counterclockwise to its “purge” position, and do the same
with the pump valve. Purge the probe and the vacuum tube using the
squeeze bulb. If condensation occurs in the probe and the flask
valve area, heat the probe, and purge until the condensation
disappears. Next, turn the pump valve to its “vent” position. Turn
the flask valve clockwise to its “evacuate” position, and record
the difference in the mercury levels in the manometer. The absolute
internal pressure in the flask (Pi) is equal to the barometric
pressure less the manometer reading. Immediately turn the flask
valve to the “sample” position, and permit the gas to enter the
flask until pressures in the flask and sample line (i.e.,
duct, stack) are equal. This will usually require about 15 seconds;
a longer period indicates a plug in the probe, which must be
corrected before sampling is continued. After collecting the
sample, turn the flask valve to its “purge” position, and
disconnect the flask from the sampling train.
8.1.3 Shake the flask for at least 5 minutes.
8.1.4 If the gas being sampled contains insufficient oxygen for
the conversion of NO to NO2 (e.g., an applicable subpart of
the standards may require taking a sample of a calibration gas
mixture of NO in N2), then introduce oxygen into the flask to
permit this conversion. Oxygen may be introduced into the flask by
one of three methods: (1) Before evacuating the sampling flask,
flush with pure cylinder oxygen, then evacuate flask to 75 mm (3
in.) Hg absolute pressure or less; or (2) inject oxygen into the
flask after sampling; or (3) terminate sampling with a minimum of
50 mm (2 in.) Hg vacuum remaining in the flask, record this final
pressure, and then vent the flask to the atmosphere until the flask
pressure is almost equal to atmospheric pressure.
8.2 Sample Recovery. Let the flask sit for a minimum of 16
hours, and then shake the contents for 2 minutes.
8.2.1 Connect the flask to a mercury filled U-tube manometer.
Open the valve from the flask to the manometer, and record the
flask temperature (Tf), the barometric pressure, and the difference
between the mercury levels in the manometer. The absolute internal
pressure in the flask (Pf) is the barometric pressure less the
manometer reading. Transfer the contents of the flask to a
leak-free polyethylene bottle. Rinse the flask twice with 5 ml
portions of water, and add the rinse water to the bottle. Adjust
the pH to between 9 and 12 by adding 1 N NaOH, dropwise (about 25
to 35 drops). Check the pH by dipping a stirring rod into the
solution and then touching the rod to the pH test paper. Remove as
little material as possible during this step. Mark the height of
the liquid level so that the container can be checked for leakage
after transport. Label the container to identify clearly its
contents. Seal the container for shipping.
9.0 Quality Control
Section
Quality control measure
Effect
10.1
Spectrophotometer
calibration
Ensure linearity of
spectrophotometer response to standards.
10.0 Calibration and Standardization
10.1 Spectrophotometer.
10.1.1 Optimum Wavelength Determination.
10.1.1.1 Calibrate the wavelength scale of the spectrophotometer
every 6 months. The calibration may be accomplished by using an
energy source with an intense line emission such as a mercury lamp,
or by using a series of glass filters spanning the measuring range
of the spectrophotometer. Calibration materials are available
commercially and from the National Institute of Standards and
Technology. Specific details on the use of such materials should be
supplied by the vendor; general information about calibration
techniques can be obtained from general reference books on
analytical chemistry. The wavelength scale of the spectrophotometer
must read correctly within 5 nm at all calibration points;
otherwise, repair and recalibrate the spectrophotometer. Once the
wavelength scale of the spectrophotometer is in proper calibration,
use 410 nm as the optimum wavelength for the measurement of the
absorbance of the standards and samples.
10.1.1.2 Alternatively, a scanning procedure may be employed to
determine the proper measuring wavelength. If the instrument is a
double-beam spectrophotometer, scan the spectrum between 400 and
415 nm using a 200 µg NO2 standard solution in the sample cell and
a blank solution in the reference cell. If a peak does not occur,
the spectrophotometer is probably malfunctioning and should be
repaired. When a peak is obtained within the 400 to 415 nm range,
the wavelength at which this peak occurs shall be the optimum
wavelength for the measurement of absorbance of both the standards
and the samples. For a single-beam spectrophotometer, follow the
scanning procedure described above, except scan separately the
blank and standard solutions. The optimum wavelength shall be the
wavelength at which the maximum difference in absorbance between
the standard and the blank occurs.
10.1.2 Determination of Spectrophotometer Calibration Factor Kc.
Add 0 ml, 2.0 ml, 4.0 ml, 6.0 ml, and 8.0 ml of the KNO3 working
standard solution (1 ml = 100 µg NO2) to a series of five 50-ml
volumetric flasks. To each flask, add 25 ml of absorbing solution
and 10 ml water. Add 1 N NaOH to each flask until the pH is between
9 and 12 (about 25 to 35 drops). Dilute to the mark with water. Mix
thoroughly, and pipette a 25-ml aliquot of each solution into a
separate porcelain evaporating dish. Beginning with the evaporation
step, follow the analysis procedure of section 11.2 until the
solution has been transferred to the 100-ml volumetric flask and
diluted to the mark. Measure the absorbance of each solution at the
optimum wavelength as determined in section 10.1.1. This
calibration procedure must be repeated on each day that samples are
analyzed. Calculate the spectrophotometer calibration factor as
shown in section 12.2.
10.1.3 Spectrophotometer Calibration Quality Control. Multiply
the absorbance value obtained for each standard by the Kc factor
(reciprocal of the least squares slope) to determine the distance
each calibration point lies from the theoretical calibration line.
The difference between the calculated concentration values and the
actual concentrations (i.e., 100, 200, 300, and 400 µg NO2)
should be less than 7 percent for all standards.
10.2 Barometer. Calibrate against a mercury barometer or
NIST-traceable barometer prior to the field test.
10.3 Temperature Gauge. Calibrate dial thermometers against
mercury-in-glass thermometers. An alternative mercury-free
thermometer may be used if the thermometer is, at a minimum,
equivalent in terms of performance or suitably effective for the
specific temperature measurement application.
10.4 Vacuum Gauge. Calibrate mechanical gauges, if used, against
a mercury manometer such as that specified in section 6.1.6.
10.5 Analytical Balance. Calibrate against standard weights.
11.0 Analytical Procedures
11.1 Sample Loss Check. Note the level of the liquid in the
container, and confirm whether any sample was lost during shipment.
Note this on the analytical data sheet. If a noticeable amount of
leakage has occurred, either void the sample or use methods,
subject to the approval of the Administrator, to correct the final
results.
11.2 Sample Preparation. Immediately prior to analysis, transfer
the contents of the shipping container to a 50 ml volumetric flask,
and rinse the container twice with 5 ml portions of water. Add the
rinse water to the flask, and dilute to mark with water; mix
thoroughly. Pipette a 25-ml aliquot into the porcelain evaporating
dish. Return any unused portion of the sample to the polyethylene
storage bottle. Evaporate the 25-ml aliquot to dryness on a steam
bath, and allow to cool. Add 2 ml phenoldisulfonic acid solution to
the dried residue, and triturate thoroughly with a polyethylene
policeman. Make sure the solution contacts all the residue. Add 1
ml water and 4 drops of concentrated sulfuric acid. Heat the
solution on a steam bath for 3 minutes with occasional stirring.
Allow the solution to cool, add 20 ml water, mix well by stirring,
and add concentrated ammonium hydroxide, dropwise, with constant
stirring, until the pH is 10 (as determined by pH paper). If the
sample contains solids, these must be removed by filtration
(centrifugation is an acceptable alternative, subject to the
approval of the Administrator) as follows: Filter through Whatman
No. 41 filter paper into a 100-ml volumetric flask. Rinse the
evaporating dish with three 5-ml portions of water. Filter these
three rinses. Wash the filter with at least three 15-ml portions of
water. Add the filter washings to the contents of the volumetric
flask, and dilute to the mark with water. If solids are absent, the
solution can be transferred directly to the 100-ml volumetric flask
and diluted to the mark with water.
11.3 Sample Analysis. Mix the contents of the flask thoroughly,
and measure the absorbance at the optimum wavelength used for the
standards (section 10.1.1), using the blank solution as a zero
reference. Dilute the sample and the blank with equal volumes of
water if the absorbance exceeds A4, the absorbance of the 400-µg
NO2 standard (see section 10.1.3).
12.0 Data Analysis and Calculations
Carry out the calculations, retaining at least one extra
significant figure beyond that of the acquired data. Round off
figures after final calculations.
12.1 12.1 Nomenclature
A = Absorbance of sample. A1 = Absorbance of the 100-µg NO2
standard. A2 = Absorbance of the 200-µg NO2 standard. A3 =
Absorbance of the 300-µg NO2 standard. A4 = Absorbance of the
400-µg NO2 standard. C = Concentration of NOX as NO2, dry basis,
corrected to standard conditions, mg/dsm 3 (lb/dscf). F = Dilution
factor (i.e., 25/5, 25/10, etc., required only if
sample dilution was needed to reduce the absorbance into the range
of the calibration). Kc = Spectrophotometer calibration factor. M =
Mass of NOX as NO2 in gas sample, µg. Pf = Final absolute pressure
of flask, mm Hg (in. Hg). Pi = Initial absolute pressure of flask,
mm Hg (in. Hg). Pstd = Standard absolute pressure, 760 mm Hg (29.92
in. Hg). Tf = Final absolute temperature of flask, °K (°R). Ti =
Initial absolute temperature of flask, °K (°R). Tstd = Standard
absolute temperature, 293 °K (528°R). Vsc = Sample volume at
standard conditions (dry basis), ml. Vf = Volume of flask and
valve, ml. Va = Volume of absorbing solution, 25 ml.
12.2 Spectrophotometer Calibration Factor.
12.3 Sample Volume, Dry Basis, Corrected to Standard
Conditions.
Where: K1 = 0.3858 °K/mm Hg for metric units,
K1 = 17.65 °R/in. Hg for English units.
12.4 Total µg NO2 per sample.
Where: 2 = 50/25, the aliquot factor. Note:
If other than a 25-ml aliquot is used for analysis, the factor 2
must be replaced by a corresponding factor.
12.5 Sample Concentration, Dry Basis, Corrected to Standard
Conditions.
Where: K2 = 10 3 (mg/m 3)/(µg/ml) for metric
units, K2 = 6.242 × 10−5 (lb/scf)/(µg/ml) for English units. 13.0
Method Performance
13.1 Range. The analytical range of the method has been
determined to be 2 to 400 milligrams NOX (as NO2) per dry standard
cubic meter, without having to dilute the sample.
1. Standard Methods of Chemical Analysis. 6th ed. New York, D.
Van Nostrand Co., Inc. 1962. Vol. 1, pp. 329-330.
2. Standard Method of Test for Oxides of Nitrogen in Gaseous
Combustion Products (Phenoldisulfonic Acid Procedure). In: 1968
Book of ASTM Standards, Part 26. Philadelphia, PA. 1968. ASTM
Designation D 1608-60, pp. 725-729.
3. Jacob, M.B. The Chemical Analysis of Air Pollutants. New
York. Interscience Publishers, Inc. 1960. Vol. 10, pp. 351-356.
4. Beatty, R.L., L.B. Berger, and H.H. Schrenk. Determination of
Oxides of Nitrogen by the Phenoldisulfonic Acid Method. Bureau of
Mines, U.S. Dept. of Interior. R.I. 3687. February 1943.
5. Hamil, H.F. and D.E. Camann. Collaborative Study of Method
for the Determination of Nitrogen Oxide Emissions from Stationary
Sources (Fossil Fuel-Fired Steam Generators). Southwest Research
Institute Report for Environmental Protection Agency. Research
Triangle Park, NC. October 5, 1973.
6. Hamil, H.F. and R.E. Thomas. Collaborative Study of Method
for the Determination of Nitrogen Oxide Emissions from Stationary
Sources (Nitric Acid Plants). Southwest Research Institute Report
for Environmental Protection Agency. Research Triangle Park, NC.
May 8, 1974.
7. Stack Sampling Safety Manual (Draft). U.S. Environmental
Protection Agency, Office of Air Quality Planning and Standards,
Research Triangle Park, NC. September 1978.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 7A -
Determination of Nitrogen Oxide Emissions From Stationary Sources
(Ion Chromatographic Method) Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 3, Method 5, and Method
7.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Nitrogen oxides
(NOX), as NO2, including:
Nitric oxide
(NO)
10102-43-9
Nitrogen
dioxide (NO2)
10102-44-0
65-655 ppmv
1.2 Applicability. This method is applicable for the
determination of NOX emissions from stationary sources.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
A grab sample is collected in an evacuated flask containing a
dilute sulfuric acid-hydrogen peroxide absorbing solution. The
nitrogen oxides, excluding nitrous oxide (N2O), are oxidized to
nitrate and measured by ion chromatography.
3.0 Definitions [Reserved] 4.0 Interferences
Biased results have been observed when sampling under conditions
of high sulfur dioxide concentrations. At or above 2100 ppm SO2,
use five times the H2O2 concentration of the Method 7 absorbing
solution. Laboratory tests have shown that high concentrations of
SO2 (about 2100 ppm) cause low results in Method 7 and 7A.
Increasing the H2O2 concentration to five times the original
concentration eliminates this bias. However, when no SO2 is
present, increasing the concentration by five times results in a
low bias.
5.0 Safety
5.1 This method may involve hazardous materials, operations, and
equipment. This test method may not address all of the safety
problems associated with its use. It is the responsibility of the
user of this test method to establish appropriate safety and health
practices and to determine the applicability of regulatory
limitations prior to performing this test method.
5.2 Corrosive reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water at least 15 minutes. Remove clothing
under shower and decontaminate. Treat residual chemical burns as
thermal burns.
5.2.1 Hydrogen Peroxide (H2O2). Irritating to eyes, skin, nose,
and lungs.
5.2.2 Sulfuric Acid (H2SO4). Rapidly destructive to body tissue.
Will cause third degree burns. Eye damage may result in blindness.
Inhalation may be fatal from spasm of the larynx, usually within 30
minutes. May cause lung tissue damage with edema. 3 mg/m 3 will
cause lung damage in uninitiated. 1 mg/m 3 for 8 hours will cause
lung damage or, in higher concentrations, death. Provide
ventilation to limit inhalation. Reacts violently with metals and
organics.
6.0 Equipment and Supplies
6.1 Sample Collection. Same as in Method 7, section 6.1.
6.2 Sample Recovery. Same as in Method 7, section 6.2, except
the stirring rod and pH paper are not needed.
6.3 Analysis. For the analysis, the following equipment and
supplies are required. Alternative instrumentation and procedures
will be allowed provided the calibration precision requirement in
section 10.1.2 can be met.
6.3.1 Volumetric Pipets. Class A;1-, 2-, 4-, 5-ml (two for the
set of standards and one per sample), 6-, 10-, and graduated 5-ml
sizes.
6.3.2 Volumetric Flasks. 50-ml (two per sample and one per
standard), 200-ml, and 1-liter sizes.
6.3.3 Analytical Balance. To measure to within 0.1 mg.
6.3.4 Ion Chromatograph. The ion chromatograph should have at
least the following components:
6.3.4.1 Columns. An anion separation or other column capable of
resolving the nitrate ion from sulfate and other species present
and a standard anion suppressor column (optional). Suppressor
columns are produced as proprietary items; however, one can be
produced in the laboratory using the resin available from BioRad
Company, 32nd and Griffin Streets, Richmond, California. Peak
resolution can be optimized by varying the eluent strength or
column flow rate, or by experimenting with alternative columns that
may offer more efficient separation. When using guard columns with
the stronger reagent to protect the separation column, the analyst
should allow rest periods between injection intervals to purge
possible sulfate buildup in the guard column.
6.3.4.2 Pump. Capable of maintaining a steady flow as required
by the system.
6.3.4.3 Flow Gauges. Capable of measuring the specified system
flow rate.
6.3.4.4 Conductivity Detector.
6.3.4.5 Recorder. Compatible with the output voltage range of
the detector.
7.0 Reagents and Standards
Unless otherwise indicated, it is intended that all reagents
conform to the specifications established by the Committee on
Analytical Reagents of the American Chemical Society, where such
specifications are available; otherwise, use the best available
grade.
7.1 Sample Collection. Same as Method 7, section 7.1.
7.2 Sample Recovery. Same as Method 7, section 7.1.1.
7.3 Analysis. The following reagents and standards are required
for analysis:
7.3.1 Water. Same as Method 7, section 7.1.1.
7.3.2 Stock Standard Solution, 1 mg NO2/ml. Dry an adequate
amount of sodium nitrate (NaNO3) at 105 to 110 °C (221 to 230 °F)
for a minimum of 2 hours just before preparing the standard
solution. Then dissolve exactly 1.847 g of dried NaNO3 in water,
and dilute to l liter in a volumetric flask. Mix well. This
solution is stable for 1 month and should not be used beyond this
time.
7.3.3 Working Standard Solution, 25 µg/ml. Dilute 5 ml of the
standard solution to 200 ml with water in a volumetric flask, and
mix well.
7.3.4 Eluent Solution. Weigh 1.018 g of sodium carbonate
(Na2CO3) and 1.008 g of sodium bicarbonate (NaHCO3), and dissolve
in 4 liters of water. This solution is 0.0024 M Na2CO3/0.003 M
NaHCO3. Other eluents appropriate to the column type and capable of
resolving nitrate ion from sulfate and other species present may be
used.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Sampling. Same as in Method 7, section 8.1.
8.2 Sample Recovery. Same as in Method 7, section 8.2, except
delete the steps on adjusting and checking the pH of the sample. Do
not store the samples more than 4 days between collection and
analysis.
9.0 Quality Control
Section
Quality control measure
Effect
10.1
Ion chromatographn
calibration
Ensure linearity of ion
chromatograph response to standards.
10.0 Calibration and Standardizations
10.1 Ion Chromatograph.
10.1.1 Determination of Ion Chromatograph Calibration Factor S.
Prepare a series of five standards by adding 1.0, 2.0, 4.0, 6.0,
and 10.0 ml of working standard solution (25 µg/ml) to a series of
five 50-ml volumetric flasks. (The standard masses will equal 25,
50, 100, 150, and 250 µg.) Dilute each flask to the mark with
water, and mix well. Analyze with the samples as described in
section 11.2, and subtract the blank from each value. Prepare or
calculate a linear regression plot of the standard masses in µg
(x-axis) versus their peak height responses in millimeters
(y-axis). (Take peak height measurements with symmetrical peaks; in
all other cases, calculate peak areas.) From this curve, or
equation, determine the slope, and calculate its reciprocal to
denote as the calibration factor, S.
10.1.2 Ion Chromatograph Calibration Quality Control. If any
point on the calibration curve deviates from the line by more than
7 percent of the concentration at that point, remake and reanalyze
that standard. This deviation can be determined by multiplying S
times the peak height response for each standard. The resultant
concentrations must not differ by more than 7 percent from each
known standard mass (i.e., 25, 50, 100, 150, and 250
µg).
10.2 Conductivity Detector. Calibrate according to
manufacturer's specifications prior to initial use.
10.3 Barometer. Calibrate against a mercury barometer.
10.4 Temperature Gauge. Calibrate dial thermometers against
mercury-in-glass thermometers. An alternative mercury-free
thermometer may be used if the thermometer is, at a minimum,
equivalent in terms of performance or suitably effective for the
specific temperature measurement application.
10.5 Vacuum Gauge. Calibrate mechanical gauges, if used, against
a mercury manometer such as that specified in section 6.1.6 of
Method 7.
10.6 Analytical Balance. Calibrate against standard weights.
11.0 Analytical Procedures
11.1 Sample Preparation.
11.1.1 Note on the analytical data sheet, the level of the
liquid in the container, and whether any sample was lost during
shipment. If a noticeable amount of leakage has occurred, either
void the sample or use methods, subject to the approval of the
Administrator, to correct the final results. Immediately before
analysis, transfer the contents of the shipping container to a
50-ml volumetric flask, and rinse the container twice with 5 ml
portions of water. Add the rinse water to the flask, and dilute to
the mark with water. Mix thoroughly.
11.1.2 Pipet a 5-ml aliquot of the sample into a 50-ml
volumetric flask, and dilute to the mark with water. Mix
thoroughly. For each set of determinations, prepare a reagent blank
by diluting 5 ml of absorbing solution to 50 ml with water.
(Alternatively, eluent solution may be used instead of water in all
sample, standard, and blank dilutions.)
11.2 Analysis.
11.2.1 Prepare a standard calibration curve according to section
10.1.1. Analyze the set of standards followed by the set of samples
using the same injection volume for both standards and samples.
Repeat this analysis sequence followed by a final analysis of the
standard set. Average the results. The two sample values must agree
within 5 percent of their mean for the analysis to be valid.
Perform this duplicate analysis sequence on the same day. Dilute
any sample and the blank with equal volumes of water if the
concentration exceeds that of the highest standard.
11.2.2 Document each sample chromatogram by listing the
following analytical parameters: injection point, injection volume,
nitrate and sulfate retention times, flow rate, detector
sensitivity setting, and recorder chart speed.
12.0 Data Analysis and Calculations
Carry out the calculations, retaining at least one extra
significant figure beyond that of the acquired data. Round off
figures after final calculations.
12.1 Sample Volume. Calculate the sample volume Vsc (in ml), on
a dry basis, corrected to standard conditions, using Equation 7-2
of Method 7.
12.2 Sample Concentration of NOX as NO2.
12.2.1 Calculate the sample concentration C (in mg/dscm) as
follows:
Where: H = Sample peak height, mm. S =
Calibration factor, µg/mm. F = Dilution factor (required only if
sample dilution was needed to reduce the concentration into the
range of calibration), dimensionless. 10 4 = 1:10 dilution times
conversion factor of: (mg/10 3 µg)(10 6 ml/m 3).
12.2.2 If desired, the concentration of NO2 may be calculated as
ppm NO2 at standard conditions as follows:
13.1 Range. The analytical range of the method is from 125 to
1250 mg NOX/m 3 as NO2 (65 to 655 ppmv), and higher concentrations
may be analyzed by diluting the sample. The lower detection limit
is approximately 19 mg/m 3 (10 ppmv), but may vary among
instruments.
1. Mulik, J.D., and E. Sawicki. Ion Chromatographic Analysis of
Environmental Pollutants. Ann Arbor, Ann Arbor Science Publishers,
Inc. Vol. 2, 1979.
2. Sawicki, E., J.D. Mulik, and E. Wittgenstein. Ion
Chromatographic Analysis of Environmental Pollutants. Ann Arbor,
Ann Arbor Science Publishers, Inc. Vol. 1. 1978.
3. Siemer, D.D. Separation of Chloride and Bromide from Complex
Matrices Prior to Ion Chromatographic Determination. Anal. Chem.
52(12):1874-1877. October 1980.
4. Small, H., T.S. Stevens, and W.C. Bauman. Novel Ion Exchange
Chromatographic Method Using Conductimetric Determination. Anal.
Chem. 47(11):1801. 1975.
5. Yu, K.K., and P.R. Westlin. Evaluation of Reference Method 7
Flask Reaction Time. Source Evaluation Society Newsletter.
4(4). November 1979. 10 pp.
6. Stack Sampling Safety Manual (Draft). U.S. Environmental
Protection Agency, Office of Air Quality Planning and Standard,
Research Triangle Park, NC. September 1978.
17.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
Method 7B - Determination of Nitrogen Oxide Emissions From
Stationary Sources (Ultraviolet Spectrophotometric Method) Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 5, and Method 7.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Nitrogen oxides
(NOX), as NO2, including:
Nitric oxide
(NO)
10102-43-9
Nitrogen
dioxide (NO2)
10102-44-0
30-786 ppmv
1.2 Applicability. This method is applicable for the
determination of NOX emissions from nitric acid plants.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A grab sample is collected in an evacuated flask containing
a dilute sulfuric acid-hydrogen peroxide absorbing solution; the
NOX, excluding nitrous oxide (N2O), are measured by ultraviolet
spectrophotometry.
5.1 This method may involve hazardous materials, operations, and
equipment. This test method may not address all of the safety
problems associated with its use. It is the responsibility of the
user of this test method to establish appropriate safety and health
practices and to determine the applicability of regulatory
limitations prior to performing this test method.
5.2 Corrosive reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water at least 15 minutes. Remove clothing
under shower and decontaminate. Treat residual chemical burn as
thermal burn.
5.2.1 Hydrogen Peroxide (H2O2). Irritating to eyes, skin, nose,
and lungs.
5.2.2 Sodium Hydroxide (NaOH). Causes severe damage to eyes and
skin. Inhalation causes irritation to nose, throat, and lungs.
Reacts exothermically with limited amounts of water.
5.2.3 Sulfuric Acid (H2SO4). Rapidly destructive to body tissue.
Will cause third degree burns. Eye damage may result in blindness.
Inhalation may be fatal from spasm of the larynx, usually within 30
minutes. May cause lung tissue damage with edema. 3 mg/m 3 will
cause lung damage in uninitiated. 1 mg/m 3 for 8 hours will cause
lung damage or, in higher concentrations, death. Provide
ventilation to limit inhalation. Reacts violently with metals and
organics.
6.0 Equipment and Supplies
6.1 Sample Collection. Same as Method 7, section 6.1.
6.2 Sample Recovery. The following items are required for sample
recovery:
6.2.1 Wash Bottle. Polyethylene or glass.
6.2.2 Volumetric Flasks. 100-ml (one for each sample).
6.3 Analysis. The following items are required for analysis:
6.3.1 Volumetric Pipettes. 5-, 10-, 15-, and 20-ml to make
standards and sample dilutions.
6.3.2 Volumetric Flasks. 1000- and 100-ml for preparing
standards and dilution of samples.
6.3.3 Spectrophotometer. To measure ultraviolet absorbance at
210 nm.
6.3.4 Analytical Balance. To measure to within 0.1 mg.
7.0 Reagents and Standards Note:
Unless otherwise indicated, all reagents are to conform to the
specifications established by the Committee on Analytical Reagents
of the American Chemical Society, where such specifications are
available. Otherwise, use the best available grade.
7.1 Sample Collection. Same as Method 7, section 7.1. It is
important that the amount of hydrogen peroxide in the absorbing
solution not be increased. Higher concentrations of peroxide may
interfere with sample analysis.
7.2 Sample Recovery. Same as Method 7, section 7.2.
7.3 Analysis. Same as Method 7, sections 7.3.1, 7.3.3, and
7.3.4, with the addition of the following:
7.3.1 Working Standard KNO3 Solution. Dilute 10 ml of the
standard solution to 1000 ml with water. One milliliter of the
working standard is equivalent to 10 µg NO2.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Sample Collection. Same as Method 7, section 8.1.
8.2 Sample Recovery.
8.2.1 Let the flask sit for a minimum of 16 hours, and then
shake the contents for 2 minutes.
8.2.2 Connect the flask to a mercury filled U-tube manometer.
Open the valve from the flask to the manometer, and record the
flask temperature (Tf), the barometric pressure, and the difference
between the mercury levels in the manometer. The absolute internal
pressure in the flask (Pf) is the barometric pressure less the
manometer reading.
8.2.3 Transfer the contents of the flask to a leak-free wash
bottle. Rinse the flask three times with 10-ml portions of water,
and add to the bottle. Mark the height of the liquid level so that
the container can be checked for leakage after transport. Label the
container to identify clearly its contents. Seal the container for
shipping.
9.0 Quality Control
Section
Quality control measure
Effect
10.1
Spectrophotometer
calibration
Ensures linearity of
spectrophotometer response to standards.
10.0 Calibration and Standardizations
Same as Method 7, sections 10.2 through 10.5, with the addition
of the following:
10.1 Determination of Spectrophotometer Standard Curve. Add 0
ml, 5 ml, 10 ml, 15 ml, and 20 ml of the KNO3 working standard
solution (1 ml = 10 µg NO2) to a series of five 100-ml volumetric
flasks. To each flask, add 5 ml of absorbing solution. Dilute to
the mark with water. The resulting solutions contain 0.0, 50, 100,
150, and 200 µg NO2, respectively. Measure the absorbance by
ultraviolet spectrophotometry at 210 nm, using the blank as a zero
reference. Prepare a standard curve plotting absorbance vs. µg
NO2.
Note:
If other than a 20-ml aliquot of sample is used for analysis,
then the amount of absorbing solution in the blank and standards
must be adjusted such that the same amount of absorbing solution is
in the blank and standards as is in the aliquot of sample used.
10.1.1 Calculate the spectrophotometer calibration factor as
follows:
Where: Mi = Mass of NO2 in standard i, µg. Ai =
Absorbance of NO2 standard i. n = Total number of calibration
standards.
10.1.2 For the set of calibration standards specified here,
Equation 7B-1 simplifies to the following:
10.2 Spectrophotometer Calibration Quality Control. Multiply the
absorbance value obtained for each standard by the Kc factor
(reciprocal of the least squares slope) to determine the distance
each calibration point lies from the theoretical calibration line.
The difference between the calculated concentration values and the
actual concentrations (i.e., 50, 100, 150, and 200 µg NO2)
should be less than 7 percent for all standards.
11.0 Analytical Procedures
11.1 Sample Loss Check. Note the level of the liquid in the
container, and confirm whether any sample was lost during shipment.
Note this on the analytical data sheet. If a noticeable amount of
leakage has occurred, either void the sample or use methods,
subject to the approval of the Administrator, to correct the final
results.
11.2 Sample Preparation. Immediately prior to analysis, transfer
the contents of the shipping container to a 100-ml volumetric
flask, and rinse the container twice with 5-ml portions of water.
Add the rinse water to the flask, and dilute to mark with
water.
11.3 Sample Analysis. Mix the contents of the flask thoroughly
and pipette a 20 ml-aliquot of sample into a 100-ml volumetric
flask. Dilute to the mark with water. Using the blank as zero
reference, read the absorbance of the sample at 210 nm.
11.4 Audit Sample Analysis. Same as Method 7, section 11.4,
except that a set of audit samples must be analyzed with each set
of compliance samples or once per analysis day, or once per week
when averaging continuous samples.
12.0 Data Analysis and Calculations
Same as Method 7, section 12.0, except replace section 12.3 with
the following:
12.1 Total µg NO2 Per Sample.
Where: 5 = 100/20, the aliquot factor. Note:
If other than a 20-ml aliquot is used for analysis, the factor 5
must be replaced by a corresponding factor.
13.0 Method Performance
13.1 Range. The analytical range of the method as outlined has
been determined to be 57 to 1500 milligrams NOX (as NO2) per dry
standard cubic meter, or 30 to 786 parts per million by volume
(ppmv) NOX.
1. National Institute for Occupational Safety and Health.
Recommendations for Occupational Exposure to Nitric Acid. In:
Occupational Safety and Health Reporter. Washington, D.C. Bureau of
National Affairs, Inc. 1976. p. 149.
2. Rennie, P.J., A.M. Sumner, and F.B. Basketter. Determination
of Nitrate in Raw, Potable, and Waste Waters by Ultraviolet
Spectrophotometry. Analyst. 104:837. September 1979.
17.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
Method 7C - Determination of Nitrogen Oxide Emissions From
Stationary Sources (Alkaline Permanganate/Colorimetric Method)
Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 3, Method 6 and Method
7.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS no.
Sensitivity
Nitrogen oxides
(NOX), as NO2, including:
Nitric oxide
(NO)
10102-43-9
Nitrogen
dioxide (NO2)
10102-44-07
ppmv
1.2 Applicability. This method applies to the measurement of NOX
emissions from fossil-fuel fired steam generators, electric utility
plants, nitric acid plants, or other sources as specified in the
regulations.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
An integrated gas sample is extracted from the stack and passed
through impingers containing an alkaline potassium permanganate
solution; NOX (NO + NO2) emissions are oxidized to NO2 and NO3.
Then NO3−is reduced to NO2−with cadmium, and the NO2−is analyzed
colorimetrically.
3.0 Definitions [Reserved] 4.0 Interferences
Possible interferents are sulfur dioxides (SO2) and ammonia
(NH3).
4.1 High concentrations of SO2 could interfere because SO2
consumes MnO4 (as does NOX) and, therefore, could reduce the NOX
collection efficiency. However, when sampling emissions from a
coal-fired electric utility plant burning 2.1 percent sulfur coal
with no control of SO2 emissions, collection efficiency was not
reduced. In fact, calculations show that sampling 3000 ppm SO2 will
reduce the MnO4 concentration by only 5 percent if all the SO2 is
consumed in the first impinger.
4.2 Ammonia (NH3) is slowly oxidized to NO3− by the absorbing
solution. At 100 ppm NH3 in the gas stream, an interference of 6
ppm NOX (11 mg NO2/m 3) was observed when the sample was analyzed
10 days after collection. Therefore, the method may not be
applicable to plants using NH3 injection to control NOX emissions
unless means are taken to correct the results. An equation has been
developed to allow quantification of the interference and is
discussed in Reference 5 of section 16.0.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Corrosive Reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water for at least 15 minutes. Remove
clothing under shower and decontaminate. Treat residual chemical
burns as thermal burns.
5.2.1 Hydrochloric Acid (HCl). Highly toxic and corrosive.
Causes severe damage to skin. Vapors are highly irritating to eyes,
skin, nose, and lungs, causing severe damage. May cause bronchitis,
pneumonia, or edema of lungs. Exposure to vapor concentrations of
0.13 to 0.2 percent can be lethal in minutes. Will react with
metals, producing hydrogen.
5.2.2 Oxalic Acid (COOH)2. Poisonous. Irritating to eyes, skin,
nose, and throat.
5.2.3 Sodium Hydroxide (NaOH). Causes severe damage to eye
tissues and to skin. Inhalation causes irritation to nose, throat,
and lungs. Reacts exothermically with small amounts of water.
6.1 Sample Collection and Sample Recovery. A schematic of the
Method 7C sampling train is shown in Figure 7C-1, and component
parts are discussed below. Alternative apparatus and procedures are
allowed provided acceptable accuracy and precision can be
demonstrated to the satisfaction of the Administrator.
6.1.1 Probe. Borosilicate glass tubing, sufficiently heated to
prevent water condensation and equipped with an in-stack or heated
out-of-stack filter to remove particulate matter (a plug of glass
wool is satisfactory for this purpose). Stainless steel or Teflon
tubing may also be used for the probe.
6.1.2 Impingers. Three restricted-orifice glass impingers,
having the specifications given in Figure 7C-2, are required for
each sampling train. The impingers must be connected in series with
leak-free glass connectors. Stopcock grease may be used, if
necessary, to prevent leakage. (The impingers can be fabricated by
a glass blower if not available commercially.)
6.1.3 Glass Wool, Stopcock Grease, Drying Tube, Valve, Pump,
Barometer, and Vacuum Gauge and Rotameter. Same as in Method 6,
sections 6.1.1.3, 6.1.1.4, 6.1.1.6, 6.1.1.7, 6.1.1.8, 6.1.2, and
6.1.3, respectively.
6.1.4 Rate Meter. Rotameter, or equivalent, accurate to within 2
percent at the selected flow rate of between 400 and 500 ml/min
(0.014 to 0.018 cfm). For rotameters, a range of 0 to 1 liter/min
(0 to 0.035 cfm) is recommended.
6.1.5 Volume Meter. Dry gas meter (DGM) capable of measuring the
sample volume under the sampling conditions of 400 to 500 ml/min
(0.014 to 0.018 cfm) for 60 minutes within an accuracy of 2
percent.
6.1.6 Filter. To remove NOX from ambient air, prepared by adding
20 g of 5-angstrom molecular sieve to a cylindrical tube
(e.g., a polyethylene drying tube).
6.1.7 Polyethylene Bottles. 1-liter, for sample recovery.
6.1.8 Funnel and Stirring Rods. For sample recovery.
6.2 Sample Preparation and Analysis.
6.2.1 Hot Plate. Stirring type with 50- by 10-mm Teflon-coated
stirring bars.
6.2.2 Beakers. 400-, 600-, and 1000-ml capacities.
6.2.3 Filtering Flask. 500-ml capacity with side arm.
6.2.4 Buchner Funnel. 75-mm ID, with spout equipped with a 13-mm
ID by 90-mm long piece of Teflon tubing to minimize possibility of
aspirating sample solution during filtration.
6.2.7 Volumetric Flasks. 100-, 200- or 250-, 500-, and 1000-ml
capacity.
6.2.8 Watch Glasses. To cover 600- and 1000-ml beakers.
6.2.9 Graduated Cylinders. 50- and 250-ml capacities.
6.2.10 Pipettes. Class A.
6.2.11 pH Meter. To measure pH from 0.5 to 12.0.
6.2.12 Burette. 50-ml with a micrometer type stopcock. (The
stopcock is Catalog No. 8225-t-05, Ace Glass, Inc., Post Office Box
996, Louisville, Kentucky 50201.) Place a glass wool plug in bottom
of burette. Cut off burette at a height of 43 cm (17 in.) from the
top of plug, and have a blower attach a glass funnel to top of
burette such that the diameter of the burette remains essentially
unchanged. Other means of attaching the funnel are acceptable.
6.2.13 Glass Funnel. 75-mm ID at the top.
6.2.14 Spectrophotometer. Capable of measuring absorbance at 540
nm; 1-cm cells are adequate.
6.2.15 Metal Thermometers. Bimetallic thermometers, range 0 to
150 °C (32 to 300 °F).
6.2.17 Parafilm “M.” Obtained from American Can Company,
Greenwich, Connecticut 06830.
6.2.18 CO2 Measurement Equipment. Same as in Method 3, section
6.0.
7.0 Reagents and Standards
Unless otherwise indicated, it is intended that all reagents
conform to the specifications established by the Committee on
Analytical Reagents of the American Chemical Society, where such
specifications are available; otherwise, use the best available
grade.
7.1 Sample Collection.
7.1.1 Water. Deionized distilled to conform to ASTM
Specification D 1193-77 or 91 Type 3 (incorporated by reference -
see § 60.17).
7.1.2 Potassium Permanganate, 4.0 Percent (w/w), Sodium
Hydroxide, 2.0 Percent (w/w) solution (KMnO4/NaOH solution).
Dissolve 40.0 g of KMnO4 and 20.0 g of NaOH in 940 ml of water.
7.2 Sample Preparation and Analysis.
7.2.1 Water. Same as in section 7.1.1.
7.2.2 Oxalic Acid Solution. Dissolve 48 g of oxalic acid
[(COOH)2·2H2O] in water, and dilute to 500 ml. Do not heat the
solution.
7.2.3 Sodium Hydroxide, 0.5 N. Dissolve 20 g of NaOH in water,
and dilute to 1 liter.
7.2.4 Sodium Hydroxide, 10 N. Dissolve 40 g of NaOH in water,
and dilute to 100 ml.
7.2.5 Ethylenediamine Tetraacetic Acid (EDTA) Solution, 6.5
percent (w/v). Dissolve 6.5 g of EDTA (disodium salt) in water, and
dilute to 100 ml. Dissolution is best accomplished by using a
magnetic stirrer.
7.2.6 Column Rinse Solution. Add 20 ml of 6.5 percent EDTA
solution to 960 ml of water, and adjust the pH to between 11.7 and
12.0 with 0.5 N NaOH.
7.2.7 Hydrochloric Acid (HCl), 2 N. Add 86 ml of concentrated
HCl to a 500 ml-volumetric flask containing water, dilute to
volume, and mix well. Store in a glass-stoppered bottle.
7.2.8 Sulfanilamide Solution. Add 20 g of sulfanilamide (melting
point 165 to 167 °C (329 to 333 °F)) to 700 ml of water. Add, with
mixing, 50 ml concentrated phosphoric acid (85 percent), and dilute
to 1000 ml. This solution is stable for at least 1 month, if
refrigerated.
7.2.9 N-(1-Naphthyl)-Ethylenediamine Dihydrochloride (NEDA)
Solution. Dissolve 0.5 g of NEDA in 500 ml of water. An aqueous
solution should have one absorption peak at 320 nm over the range
of 260 to 400 nm. NEDA that shows more than one absorption peak
over this range is impure and should not be used. This solution is
stable for at least 1 month if protected from light and
refrigerated.
7.2.10 Cadmium. Obtained from Matheson Coleman and Bell, 2909
Highland Avenue, Norwood, Ohio 45212, as EM Laboratories Catalog
No. 2001. Prepare by rinsing in 2 N HCl for 5 minutes until the
color is silver-grey. Then rinse the cadmium with water until the
rinsings are neutral when tested with pH paper. CAUTION: H2 is
liberated during preparation. Prepare in an exhaust hood away from
any flame or combustion source.
7.2.11 Sodium Nitrite (NaNO2) Standard Solution, Nominal
Concentration, 1000 µg NO2−/ml. Desiccate NaNO2 overnight.
Accurately weigh 1.4 to 1.6 g of NaNO2 (assay of 97 percent NaNO2
or greater), dissolve in water, and dilute to 1 liter. Calculate
the exact NO2-concentration using Equation 7C-1 in section 12.2.
This solution is stable for at least 6 months under laboratory
conditions.
7.2.12 Potassium Nitrate (KNO3) Standard Solution. Dry KNO3 at
110 °C (230 °F) for 2 hours, and cool in a desiccator. Accurately
weigh 9 to 10 g of KNO3 to within 0.1 mg, dissolve in water, and
dilute to 1 liter. Calculate the exact NO3− concentration using
Equation 7C-2 in section 12.3. This solution is stable for 2 months
without preservative under laboratory conditions.
7.2.13 Spiking Solution. Pipette 7 ml of the KNO3 standard into
a 100-ml volumetric flask, and dilute to volume.
7.2.14 Blank Solution. Dissolve 2.4 g of KMnO4 and 1.2 g of NaOH
in 96 ml of water. Alternatively, dilute 60 ml of KMnO4/NaOH
solution to 100 ml.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Preparation of Sampling Train. Add 200 ml of KMnO4/NaOH
solution (Section 7.1.2) to each of three impingers, and assemble
the train as shown in Figure 7C-1. Adjust the probe heater to a
temperature sufficient to prevent water condensation.
8.2 Leak-Checks. Same as in Method 6, section 8.2.
8.3 Sample Collection.
8.3.1 Record the initial DGM reading and barometric pressure.
Determine the sampling point or points according to the appropriate
regulations (e.g., § 60.46(b)(5) of 40 CFR Part 60).
Position the tip of the probe at the sampling point, connect the
probe to the first impinger, and start the pump. Adjust the sample
flow to a value between 400 and 500 ml/min (0.014 and 0.018 cfm).
CAUTION: DO NOT EXCEED THESE FLOW RATES. Once adjusted, maintain a
constant flow rate during the entire sampling run. Sample for 60
minutes. For relative accuracy (RA) testing of continuous emission
monitors, the minimum sampling time is 1 hour, sampling 20 minutes
at each traverse point.
Note:
When the SO2 concentration is greater than 1200 ppm, the
sampling time may have to be reduced to 30 minutes to eliminate
plugging of the impinger orifice with MnO2. For RA tests with SO2
greater than 1200 ppm, sample for 30 minutes (10 minutes at each
point).
8.3.2 Record the DGM temperature, and check the flow rate at
least every 5 minutes. At the conclusion of each run, turn off the
pump, remove the probe from the stack, and record the final
readings. Divide the sample volume by the sampling time to
determine the average flow rate. Conduct the mandatory post-test
leak-check. If a leak is found, void the test run, or use
procedures acceptable to the Administrator to adjust the sample
volume for the leakage.
8.4 CO2 Measurement. During sampling, measure the CO2 content of
the stack gas near the sampling point using Method 3. The
single-point grab sampling procedure is adequate, provided the
measurements are made at least three times (near the start, midway,
and before the end of a run), and the average CO2 concentration is
computed. The Orsat or Fyrite analyzer may be used for this
analysis.
8.5 Sample Recovery. Disconnect the impingers. Pour the contents
of the impingers into a 1-liter polyethylene bottle using a funnel
and a stirring rod (or other means) to prevent spillage. Complete
the quantitative transfer by rinsing the impingers and connecting
tubes with water until the rinsings are clear to light pink, and
add the rinsings to the bottle. Mix the sample, and mark the
solution level. Seal and identify the sample container.
9.0 Quality Control
Section
Quality control measure
Effect
8.2,
10.1-10.3
Sampling equipment leak-check
and calibration
Ensure accurate measurement of
sample volume.
10.4
Spectrophotometer
calibration
Ensure linearity of
spectrophotometer response to standards
11.3
Spiked sample analysis.
Ensure reduction efficiency of
column.
10.0 Calibration and Standardizations
10.1 Volume Metering System. Same as Method 6, section 10.1. For
detailed instructions on carrying out these calibrations, it is
suggested that section 3.5.2 of Reference 4 of section 16.0 be
consulted.
10.2 Temperature Sensors and Barometer. Same as in Method 6,
sections 10.2 and 10.4, respectively.
10.3 Check of Rate Meter Calibration Accuracy (Optional).
Disconnect the probe from the first impinger, and connect the
filter. Start the pump, and adjust the rate meter to read between
400 and 500 ml/min (0.014 and 0.018 cfm). After the flow rate has
stabilized, start measuring the volume sampled, as recorded by the
dry gas meter and the sampling time. Collect enough volume to
measure accurately the flow rate. Then calculate the flow rate.
This average flow rate must be less than 500 ml/min (0.018 cfm) for
the sample to be valid; therefore, it is recommended that the flow
rate be checked as above prior to each test.
10.4 Spectrophotometer.
10.4.1 Dilute 5.0 ml of the NaNO2 standard solution to 200 ml
with water. This solution nominally contains 25 µg NO2−/ml. Use
this solution to prepare calibration standards to cover the range
of 0.25 to 3.00 µg NO2−/ml. Prepare a minimum of three standards
each for the linear and slightly nonlinear (described below) range
of the curve. Use pipettes for all additions.
10.4.2 Measure the absorbance of the standards and a water blank
as instructed in section 11.5. Plot the net absorbance vs. µg
NO2−/ml. Draw a smooth curve through the points. The curve should
be linear up to an absorbance of approximately 1.2 with a slope of
approximately 0.53 absorbance units/µg NO2−/ml. The curve should
pass through the origin. The curve is slightly nonlinear from an
absorbance of 1.2 to 1.6.
11.0 Analytical Procedures
11.1 Sample Stability. Collected samples are stable for at least
four weeks; thus, analysis must occur within 4 weeks of
collection.
11.2 Sample Preparation.
11.2.1 Prepare a cadmium reduction column as follows: Fill the
burette with water. Add freshly prepared cadmium slowly, with
tapping, until no further settling occurs. The height of the
cadmium column should be 39 cm (15 in). When not in use, store the
column under rinse solution.
Note:
The column should not contain any bands of cadmium fines. This
may occur if regenerated cadmium is used and will greatly reduce
the column lifetime.
11.2.2 Note the level of liquid in the sample container, and
determine whether any sample was lost during shipment. If a
noticeable amount of leakage has occurred, the volume lost can be
determined from the difference between initial and final solution
levels, and this value can then be used to correct the analytical
result. Quantitatively transfer the contents to a 1-liter
volumetric flask, and dilute to volume.
11.2.3 Take a 100-ml aliquot of the sample and blank (unexposed
KMnO4/NaOH) solutions, and transfer to 400-ml beakers containing
magnetic stirring bars. Using a pH meter, add concentrated H2SO4
with stirring until a pH of 0.7 is obtained. Allow the solutions to
stand for 15 minutes. Cover the beakers with watch glasses, and
bring the temperature of the solutions to 50 °C (122 °F). Keep the
temperature below 60 °C (140 °F). Dissolve 4.8 g of oxalic acid in
a minimum volume of water, approximately 50 ml, at room
temperature. Do not heat the solution. Add this solution slowly, in
increments, until the KMnO4 solution becomes colorless. If the
color is not completely removed, prepare some more of the above
oxalic acid solution, and add until a colorless solution is
obtained. Add an excess of oxalic acid by dissolving 1.6 g of
oxalic acid in 50 ml of water, and add 6 ml of this solution to the
colorless solution. If suspended matter is present, add
concentrated H2SO4 until a clear solution is obtained.
11.2.4 Allow the samples to cool to near room temperature, being
sure that the samples are still clear. Adjust the pH to between
11.7 and 12.0 with 10 N NaOH. Quantitatively transfer the mixture
to a Buchner funnel containing GF/C filter paper, and filter the
precipitate. Filter the mixture into a 500-ml filtering flask. Wash
the solid material four times with water. When filtration is
complete, wash the Teflon tubing, quantitatively transfer the
filtrate to a 500-ml volumetric flask, and dilute to volume. The
samples are now ready for cadmium reduction. Pipette a 50-ml
aliquot of the sample into a 150-ml beaker, and add a magnetic
stirring bar. Pipette in 1.0 ml of 6.5 percent EDTA solution, and
mix.
11.3 Determine the correct stopcock setting to establish a flow
rate of 7 to 9 ml/min of column rinse solution through the cadmium
reduction column. Use a 50-ml graduated cylinder to collect and
measure the solution volume. After the last of the rinse solution
has passed from the funnel into the burette, but before air
entrapment can occur, start adding the sample, and collect it in a
250-ml graduated cylinder. Complete the quantitative transfer of
the sample to the column as the sample passes through the column.
After the last of the sample has passed from the funnel into the
burette, start adding 60 ml of column rinse solution, and collect
the rinse solution until the solution just disappears from the
funnel. Quantitatively transfer the sample to a 200-ml volumetric
flask (a 250-ml flask may be required), and dilute to volume. The
samples are now ready for NO2-analysis.
Note:
Two spiked samples should be run with every group of samples
passed through the column. To do this, prepare two additional 50-ml
aliquots of the sample suspected to have the highest
NO2-concentration, and add 1 ml of the spiking solution to these
aliquots. If the spike recovery or column efficiency (see section
12.2) is below 95 percent, prepare a new column, and repeat the
cadmium reduction.
11.5 Sample Analysis. Pipette 10 ml of sample into a culture
tube. Pipette in 10 ml of sulfanilamide solution and 1.4 ml of NEDA
solution. Cover the culture tube with parafilm, and mix the
solution. Prepare a blank in the same manner using the sample from
treatment of the unexposed KMnO4/NaOH solution. Also, prepare a
calibration standard to check the slope of the calibration curve.
After a 10-minute color development interval, measure the
absorbance at 540 nm against water. Read µg NO2−/ml from the
calibration curve. If the absorbance is greater than that of the
highest calibration standard, use less than 10 ml of sample, and
repeat the analysis. Determine the NO2−concentration using the
calibration curve obtained in section 10.4.
Note:
Some test tubes give a high blank NO2− value but culture tubes
do not.
11.6 Audit Sample Analysis. Same as in Method 7, section
11.4.
12.0 Data Analysis and Calculations
Carry out calculations, retaining at least one extra significant
figure beyond that of the acquired data. Round off figures after
final calculation.
12.1 Nomenclature.
B = Analysis of blank, µg NO2−/ml. C = Concentration of NOX as NO2,
dry basis, mg/dsm 3. E = Column efficiency, dimensionless K2 = 10−3
mg/µg. m = Mass of NOX, as NO2, in sample, µg. Pbar = Barometric
pressure, mm Hg (in. Hg). Pstd = Standard absolute pressure, 760 mm
Hg (29.92 in. Hg). s = Concentration of spiking solution, µg
NO3/ml. S = Analysis of sample, µg NO2−/ml. Tm = Average dry gas
meter absolute temperature, °K. Tstd = Standard absolute
temperature, 293 °K (528 °R). Vm(std) = Dry gas volume measured by
the dry gas meter, corrected to standard conditions, dscm (dscf).
Vm = Dry gas volume as measured by the dry gas meter, scm (scf). x
= Analysis of spiked sample, µg NO2−/ml. X = Correction factor for
CO2 collection = 100/(100 − %CO2(V/V)). y = Analysis of unspiked
sample, µg NO2−/ml. Y = Dry gas meter calibration factor. 1.0 ppm
NO = 1.247 mg NO/m 3 at STP. 1.0 ppm NO2 = 1.912 mg NO2/m 3 at STP.
1 ft 3 = 2.832 × 10−2 m 3.
12.2 NO2 Concentration. Calculate the NO2 concentration of the
solution (see section 7.2.11) using the following equation:
12.3 NO3 Concentration. Calculate the NO3 concentration of the
KNO3 solution (see section 7.2.12) using the following
equation:
12.4 Sample Volume, Dry Basis, Corrected to Standard
Conditions.
Where: K1 = 0.3855 °K/mm Hg for metric units.
K1 = 17.65 °R/in. Hg for English units.
12.5 Efficiency of Cadmium Reduction Column. Calculate this
value as follows:
Where: 200 = Final volume of sample and blank
after passing through the column, ml. 1.0 = Volume of spiking
solution added, ml. 46.01=µg NO2−/µmole. 62.01=µg NO3−/µmole.
12.6 Total µg NO2.
Where: 500 = Total volume of prepared sample,
ml. 50 = Aliquot of prepared sample processed through cadmium
column, ml. 100 = Aliquot of KMnO4/NaOH solution, ml. 1000 = Total
volume of KMnO4/NaOH solution, ml.
12.7 Sample Concentration.
13.0 Method Performance
13.1 Precision. The intra-laboratory relative standard deviation
for a single measurement is 2.8 and 2.9 percent at 201 and 268 ppm
NOX, respectively.
13.2 Bias. The method does not exhibit any bias relative to
Method 7.
13.3 Range. The lower detectable limit is 13 mg NOX/m 3, as NO2
(7 ppm NOX) when sampling at 500 ml/min for 1 hour. No upper limit
has been established; however, when using the recommended sampling
conditions, the method has been found to collect NOX emissions
quantitatively up to 1782 mg NOX/m 3, as NO2 (932 ppm NOX).
1. Margeson, J.H., W.J. Mitchell, J.C. Suggs, and M.R. Midgett.
Integrated Sampling and Analysis Methods for Determining NOX
Emissions at Electric Utility Plants. U.S. Environmental Protection
Agency, Research Triangle Park, NC. Journal of the Air Pollution
Control Association. 32:1210-1215. 1982.
2. Memorandum and attachment from J.H. Margeson, Source Branch,
Quality Assurance Division, Environmental Monitoring Systems
Laboratory, to The Record, EPA. March 30, 1983. NH3 Interference in
Methods 7C and 7D.
3. Margeson, J.H., J.C. Suggs, and M.R. Midgett. Reduction of
Nitrate to Nitrite with Cadmium. Anal. Chem. 52:1955-57.
1980.
4. Quality Assurance Handbook for Air Pollution Measurement
Systems. Volume III - Stationary Source Specific Methods. U.S.
Environmental Protection Agency. Research Triangle Park, NC.
Publication No. EPA-600/4-77-027b. August 1977.
5. Margeson, J.H., et al. An Integrated Method for
Determining NOX Emissions at Nitric Acid Plants. Analytical
Chemistry. 47 (11):1801. 1975.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 7D -
Determination of Nitrogen Oxide Emissions From Stationary Sources
(Alkaline-Permanganate/Ion Chromatographic Method) Note:
This method is not inclusive with respect to specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 3, Method 6, Method 7,
and Method 7C.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Nitrogen oxides
(NOX), as NO2, including:
Nitric oxide
(NO)
10102-43-9
Nitrogen
dioxide (NO2)
10102-44-0
7 ppmv
1.2 Applicability. This method applies to the measurement of NOX
emissions from fossil-fuel fired steam generators, electric utility
plants, nitric acid plants, or other sources as specified in the
regulations.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
An integrated gas sample is extracted from the stack and passed
through impingers containing an alkaline-potassium permanganate
solution; NOX (NO + NO2) emissions are oxidized to NO3−. Then NO3−
is analyzed by ion chromatography.
3.0 Definitions [Reserved] 4.0 Interferences
Same as in Method 7C, section 4.0.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Corrosive reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water for at least 15 minutes. Remove
clothing under shower and decontaminate. Treat residual chemical
burns as thermal burns.
5.2.1 Hydrogen Peroxide (H2O2). Irritating to eyes, skin, nose,
and lungs. 30% H2O2 is a strong oxidizing agent; avoid contact with
skin, eyes, and combustible material. Wear gloves when
handling.
5.2.2 Sodium Hydroxide (NaOH). Causes severe damage to eye
tissues and to skin. Inhalation causes irritation to nose, throat,
and lungs. Reacts exothermically with limited amounts of water.
6.1 Sample Collection and Sample Recovery. Same as Method 7C,
section 6.1. A schematic of the sampling train used in performing
this method is shown in Figure 7C-1 of Method 7C.
6.2 Sample Preparation and Analysis.
6.2.1 Magnetic Stirrer. With 25- by 10-mm Teflon-coated stirring
bars.
6.2.2 Filtering Flask. 500-ml capacity with sidearm.
6.2.3 Buchner Funnel. 75-mm ID, with spout equipped with a 13-mm
ID by 90-mm long piece of Teflon tubing to minimize possibility of
aspirating sample solution during filtration.
6.2.9 Ion Chromatograph. Equipped with an anion separator column
to separate NO3−, H3 + suppressor, and necessary auxiliary
equipment. Nonsuppressed and other forms of ion chromatography may
also be used provided that adequate resolution of NO3− is obtained.
The system must also be able to resolve and detect NO2−.
7.0 Reagents and Standards Note:
Unless otherwise indicated, it is intended that all reagents
conform to the specifications established by the Committee on
Analytical Reagents of the American Chemical Society, where such
specifications are available; otherwise, use the best available
grade.
7.1 Sample Collection.
7.1.1 Water. Deionized distilled to conform to ASTM
specification D 1193-77 or 91 Type 3 (incorporated by reference -
see § 60.17).
7.1.2 Potassium Permanganate, 4.0 Percent (w/w), Sodium
Hydroxide, 2.0 Percent (w/w). Dissolve 40.0 g of KMnO4 and 20.0 g
of NaOH in 940 ml of water.
7.2.3 Blank Solution. Dissolve 2.4 g of KMnO4 and 1.2 g of NaOH
in 96 ml of water. Alternatively, dilute 60 ml of KMnO4/NaOH
solution to 100 ml.
7.2.4 KNO3 Standard Solution. Dry KNO3 at 110 °C for 2 hours,
and cool in a desiccator. Accurately weigh 9 to 10 g of KNO3 to
within 0.1 mg, dissolve in water, and dilute to 1 liter. Calculate
the exact NO3− concentration using Equation 7D-1 in section 12.2.
This solution is stable for 2 months without preservative under
laboratory conditions.
7.2.5 Eluent, 0.003 M NaHCO3/0.0024 M Na2CO3. Dissolve 1.008 g
NaHCO3 and 1.018 g Na2CO3 in water, and dilute to 4 liters. Other
eluents capable of resolving nitrate ion from sulfate and other
species present may be used.
8.0 Sample Collection, Preservation, Transport, and Storage.
8.1 Sampling. Same as in Method 7C, section 8.1.
8.2 Sample Recovery. Same as in Method 7C, section 8.2.
8.3 Sample Preparation for Analysis.
Note:
Samples must be analyzed within 28 days of collection.
8.3.1 Note the level of liquid in the sample container, and
determine whether any sample was lost during shipment. If a
noticeable amount of leakage has occurred, the volume lost can be
determined from the difference between initial and final solution
levels, and this value can then be used to correct the analytical
result. Quantitatively transfer the contents to a 1-liter
volumetric flask, and dilute to volume.
8.3.2 Sample preparation can be started 36 hours after
collection. This time is necessary to ensure that all NO2− is
converted to NO3− in the collection solution. Take a 50-ml aliquot
of the sample and blank, and transfer to 250-ml Erlenmeyer flasks.
Add a magnetic stirring bar. Adjust the stirring rate to as fast a
rate as possible without loss of solution. Add 5 percent H2O2 in
increments of approximately 5 ml using a 5-ml pipette. When the
KMnO4 color appears to have been removed, allow the precipitate to
settle, and examine the supernatant liquid. If the liquid is clear,
the H2O2 addition is complete. If the KMnO4 color persists, add
more H2O2, with stirring, until the supernatant liquid is
clear.
Note:
The faster the stirring rate, the less volume of H2O2 that will
be required to remove the KMnO4.) Quantitatively transfer the
mixture to a Buchner funnel containing GF/C filter paper, and
filter the precipitate. The spout of the Buchner funnel should be
equipped with a 13-mm ID by 90-mm long piece of Teflon tubing. This
modification minimizes the possibility of aspirating sample
solution during filtration. Filter the mixture into a 500-ml
filtering flask. Wash the solid material four times with water.
When filtration is complete, wash the Teflon tubing, quantitatively
transfer the filtrate to a 250-ml volumetric flask, and dilute to
volume. The sample and blank are now ready for NO3−analysis.
9.0 Quality Control
Section
Quality control measure
Effect
8.2,
10.1-10.3
Sampling equipment leak-check
and calibration
Ensure accurate measurement of
sample volume.
10.4
Spectrophotometer
calibration
Ensure linearity of
spectrophotometer response to standards.
11.3
Spiked sample analysis
Ensure reduction efficiency of
column.
10.0 Calibration and Standardizations
10.1 Dry Gas Meter (DGM) System.
10.1.1 Initial Calibration. Same as in Method 6, section 10.1.1.
For detailed instructions on carrying out this calibration, it is
suggested that section 3.5.2 of Citation 4 in section 16.0 of
Method 7C be consulted.
10.1.2 Post-Test Calibration Check. Same as in Method 6, section
10.1.2.
10.2 Thermometers for DGM and Barometer. Same as in Method 6,
sections 10.2 and 10.4, respectively.
10.3 Ion Chromatograph.
10.3.1 Dilute a given volume (1.0 ml or greater) of the KNO3
standard solution to a convenient volume with water, and use this
solution to prepare calibration standards. Prepare at least four
standards to cover the range of the samples being analyzed. Use
pipettes for all additions. Run standards as instructed in section
11.2. Determine peak height or area, and plot the individual values
versus concentration in µg NO3−/ml.
10.3.2 Do not force the curve through zero. Draw a smooth curve
through the points. The curve should be linear. With the linear
curve, use linear regression to determine the calibration
equation.
11.0 Analytical Procedures
11.1 The following chromatographic conditions are recommended:
0.003 M NaHCO3/0.0024 Na2CO3 eluent solution (Section 7.2.5), full
scale range, 3 µMHO; sample loop, 0.5 ml; flow rate, 2.5 ml/min.
These conditions should give a NO3− retention time of approximately
15 minutes (Figure 7D-1).
11.2 Establish a stable baseline. Inject a sample of water, and
determine whether any NO3− appears in the chromatogram. If NO3− is
present, repeat the water load/injection procedure approximately
five times; then re-inject a water sample and observe the
chromatogram. When no NO3− is present, the instrument is ready for
use. Inject calibration standards. Then inject samples and a blank.
Repeat the injection of the calibration standards (to compensate
for any drift in response of the instrument). Measure the NO3− peak
height or peak area, and determine the sample concentration from
the calibration curve.
12.0 Data Analysis and Calculations
Carry out calculations, retaining at least one extra significant
figure beyond that of the acquired data. Round off figures after
final calculation.
12.1 Nomenclature. Same as in Method 7C, section 12.1.
12.2 NO3− concentration. Calculate the NO3− concentration in the
KNO3 standard solution (see section 7.2.4) using the following
equation:
12.3 Sample Volume, Dry Basis, Corrected to Standard Conditions.
Same as in Method 7C, section 12.4.
12.4 Total µg NO2 Per Sample.
Where: 250 = Volume of prepared sample, ml.
1000 = Total volume of KMnO4 solution, ml. 50 = Aliquot of
KMnO4/NaOH solution, ml. 46.01 = Molecular weight of NO3−. 62.01 =
Molecular weight of NO3−.
12.5 Sample Concentration. Same as in Method 7C, section
12.7.
13.0 Method Performance
13.1 Precision. The intra-laboratory relative standard deviation
for a single measurement is approximately 6 percent at 200 to 270
ppm NOX.
13.2 Bias. The method does not exhibit any bias relative to
Method 7.
13.3 Range. The lower detectable limit is similar to that of
Method 7C. No upper limit has been established; however, when using
the recommended sampling conditions, the method has been found to
collect NOX emissions quantitatively up to 1782 mg NOX/m 3, as NO2
(932 ppm NOX).
Same as Method 7C, section 16.0, References 1, 2, 4, and 5.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 7E -
Determination of Nitrogen Oxides Emissions From Stationary Sources
(Instrumental Analyzer Procedure) 1.0 Scope and Application What is
Method 7E?
Method 7E is a procedure for measuring nitrogen oxides (NOX) in
stationary source emissions using a continuous instrumental
analyzer. Quality assurance and quality control requirements are
included to assure that you, the tester, collect data of known
quality. You must document your adherence to these specific
requirements for equipment, supplies, sample collection and
analysis, calculations, and data analysis. This method does not
completely describe all equipment, supplies, and sampling and
analytical procedures you will need but refers to other methods for
some of the details. Therefore, to obtain reliable results, you
should also have a thorough knowledge of these additional test
methods which are found in appendix A to this part:
(a) Method 1 - Sample and Velocity Traverses for Stationary
Sources.
(b) Method 4 - Determination of Moisture Content in Stack
Gases.
1.1 Analytes. What does this method determine? This
method measures the concentration of nitrogen oxides as NO2.
Analyte
CAS No.
Sensitivity
Nitric oxide
(NO)
10102-43-9
Typically <2% of
Nitrogen dioxide
(NO2)
10102-44-0
Calibration Span.
1.2 Applicability. When is this method required? The use
of Method 7E may be required by specific New Source Performance
Standards, Clean Air Marketing rules, State Implementation Plans,
and permits where measurement of NOX concentrations in stationary
source emissions is required, either to determine compliance with
an applicable emissions standard or to conduct performance testing
of a continuous monitoring system (CEMS). Other regulations may
also require the use of Method 7E.
1.3 Data Quality Objectives (DQO). How good must my collected
data be? Method 7E is designed to provide high-quality data for
determining compliance with Federal and State emission standards
and for relative accuracy testing of CEMS. In these and other
applications, the principal objective is to ensure the accuracy of
the data at the actual emission levels encountered. To meet this
objective, the use of EPA traceability protocol calibration gases
and measurement system performance tests are required.
1.4 Data Quality Assessment for Low Emitters. Is performance
relief granted when testing low-emission units? Yes. For
low-emitting sources, there are alternative performance
specifications for analyzer calibration error, system bias, drift,
and response time. Also, the alternative dynamic spiking procedure
in section 16 may provide performance relief for certain
low-emitting units.
2.0 Summary of Method
In this method, a sample of the effluent gas is continuously
sampled and conveyed to the analyzer for measuring the
concentration of NOX. You may measure NO and NO2 separately or
simultaneously together but, for the purposes of this method, NOX
is the sum of NO and NO2. You must meet the performance
requirements of this method to validate your data.
3.0 Definitions
3.1 Analyzer Calibration Error, for non-dilution systems,
means the difference between the manufacturer certified
concentration of a calibration gas and the measured concentration
of the same gas when it is introduced into the analyzer in direct
calibration mode.
3.2 Calibration Curve means the relationship between an
analyzer's response to the injection of a series of calibration
gases and the actual concentrations of those gases.
3.3 Calibration Gas means the gas mixture containing NOX
at a known concentration and produced and certified in accordance
with “EPA Traceability Protocol for Assay and Certification of
Gaseous Calibration Standards,” September 1997, as amended August
25, 1999, EPA-600/R-97/121 or more recent updates. The tests for
analyzer calibration error, drift, and system bias require the use
of calibration gas prepared according to this protocol. If a zero
gas is used for the low-level gas, it must meet the requirements
under the definition for “zero air material” in 40 CFR 72.2 in
place of being prepared by the traceability protocol.
3.3.1 Low-Level Gas means a calibration gas with a
concentration that is less than 20 percent of the calibration span
and may be a zero gas.
3.3.2 Mid-Level Gas means a calibration gas with a
concentration that is 40 to 60 percent of the calibration span.
3.3.3 High-Level Gas means a calibration gas with a
concentration that is equal to the calibration span.
3.4Calibration Span means the upper limit of the
analyzer's calibration that is set by the choice of high-level
calibration gas. No valid run average concentration may exceed the
calibration span. To the extent practicable, the measured emissions
should be between 20 to 100 percent of the selected calibration
span. This may not be practicable in some cases of
low-concentration measurements or testing for compliance with an
emission limit when emissions are substantially less than the
limit. In such cases, calibration spans that are practicable to
achieving the data quality objectives without being excessively
high should be chosen.
3.5 Centroidal Area means the central area of the stack
or duct that is no greater than 1 percent of the stack or duct
cross section. This area has the same geometric shape as the stack
or duct.
3.6 Converter Efficiency Gas means a calibration gas with
a known NO or NO2 concentration and of Traceability Protocol
quality.
3.7 Data Recorder means the equipment that permanently
records the concentrations reported by the analyzer.
3.8 Direct Calibration Mode means introducing the
calibration gases directly into the analyzer (or into the assembled
measurement system at a point downstream of all sample conditioning
equipment) according to manufacturer's recommended calibration
procedure. This mode of calibration applies to non-dilution-type
measurement systems.
3.9 Drift means the difference between the pre- and
post-run system bias (or system calibration error) checks at a
specific calibration gas concentration level (i.e. low-,
mid- or high-).
3.10 Gas Analyzer means the equipment that senses the gas
being measured and generates an output proportional to its
concentration.
3.11 Interference Check means the test to detect analyzer
responses to compounds other than the compound of interest, usually
a gas present in the measured gas stream, that is not adequately
accounted for in the calibration procedure and may cause
measurement bias.
3.12 Low-Concentration Analyzer means any analyzer that
operates with a calibration span of 20 ppm NOX or lower. Each
analyzer model used routinely to measure low NOX concentrations
must pass a manufacturer's stability test (MST). An MST subjects
the analyzer to a range of line voltages and temperatures that
reflect potential field conditions to demonstrate its stability
following procedures similar to those provided in 40 CFR 53.23.
Ambient-level analyzers are exempt from the MST requirements of
section 16.3. A copy of this information must be included in each
test report. Table 7E-5 lists the criteria to be met.
3.13 Measurement System means all of the equipment used
to determine the NOX concentration. The measurement system
comprises six major subsystems: Sample acquisition, sample
transport, sample conditioning, calibration gas manifold, gas
analyzer, and data recorder.
3.14 Response Time means the time it takes the
measurement system to respond to a change in gas concentration
occurring at the sampling point when the system is operating
normally at its target sample flow rate or dilution ratio.
3.15 Run means a series of gas samples taken successively
from the stack or duct. A test normally consists of a specific
number of runs.
3.16 System Bias means the difference between a
calibration gas measured in direct calibration mode and in system
calibration mode. System bias is determined before and after each
run at the low- and mid- or high-concentration levels. For
dilution-type systems, pre- and post-run system calibration error
is measured rather than system bias.
3.17 System Calibration Error applies to dilution-type
systems and means the difference between the measured concentration
of low-, mid-, or high-level calibration gas and the certified
concentration for each gas when introduced in system calibration
mode. For dilution-type systems, a 3-point system calibration error
test is conducted in lieu of the analyzer calibration error test,
and 2-point system calibration error tests are conducted in lieu of
system bias tests.
3.18 System Calibration Mode means introducing the
calibration gases into the measurement system at the probe,
upstream of the filter and all sample conditioning components.
3.19 Test refers to the series of runs required by the
applicable regulation.
4.0 Interferences
Note that interferences may vary among instruments and that
instrument-specific interferences must be evaluated through the
interference test.
5.0 Safety
What safety measures should I consider when using this
method? This method may require you to work with hazardous
materials and in hazardous conditions. We encourage you to
establish safety procedures before using the method. Among other
precautions, you should become familiar with the safety
recommendations in the gas analyzer user's manual. Occupational
Safety and Health Administration (OSHA) regulations concerning
cylinder and noxious gases may apply. Nitric oxide and NO2 are
toxic and dangerous gases. Nitric oxide is immediately converted to
NO2 upon reaction with air. Nitrogen dioxide is a highly poisonous
and insidious gas. Inflammation of the lungs from exposure may
cause only slight pain or pass unnoticed, but the resulting edema
several days later may cause death. A concentration of 100 ppm is
dangerous for even a short exposure, and 200 ppm may be fatal.
Calibration gases must be handled with utmost care and with
adequate ventilation. Emission-level exposure to these gases should
be avoided.
6.0 Equipment and Supplies
The performance criteria in this method will be met or exceeded
if you are properly using equipment designed for this
application.
6.1 What do I need for the measurement system? You may use any
equipment and supplies meeting the following specifications:
(1) Sampling system components that are not evaluated in the
system bias or system calibration error test must be glass, Teflon,
or stainless steel. Other materials are potentially acceptable,
subject to approval by the Administrator.
(2) The interference, calibration error, and system bias
criteria must be met.
(3) Sample flow rate must be maintained within 10 percent of the
flow rate at which the system response time was measured.
(4) All system components (excluding sample conditioning
components, if used) must maintain the sample temperature above the
moisture dew point. Ensure minimal contact between any condensate
and the sample gas. Section 6.2 provides example equipment
specifications for a NOX measurement system. Figure 7E-1 is a
diagram of an example dry-basis measurement system that is likely
to meet the method requirements and is provided as guidance. For
wet-basis systems, you may use alternative equipment and supplies
as needed (some of which are described in Section 6.2), provided
that the measurement system meets the applicable performance
specifications of this method.
6.2 Measurement System Components
6.2.1 Sample Probe. Glass, stainless steel, or other
approved material, of sufficient length to traverse the sample
points.
6.2.2 Particulate Filter. An in-stack or out-of-stack
filter. The filter must be made of material that is non-reactive to
the gas being sampled. The filter media for out-of-stack filters
must be included in the system bias test. The particulate filter
requirement may be waived in applications where no significant
particulate matter is expected (e.g., for emission testing
of a combustion turbine firing natural gas).
6.2.3 Sample Line. The sample line from the probe to the
conditioning system/sample pump should be made of Teflon or other
material that does not absorb or otherwise alter the sample gas.
For a dry-basis measurement system (as shown in Figure 7E-1), the
temperature of the sample line must be maintained at a sufficiently
high level to prevent condensation before the sample conditioning
components. For wet-basis measurement systems, the temperature of
the sample line must be maintained at a sufficiently high level to
prevent condensation before the analyzer.
6.2.4 Conditioning Equipment. For dry basis measurements,
a condenser, dryer or other suitable device is required to remove
moisture continuously from the sample gas. Any equipment needed to
heat the probe or sample line to avoid condensation prior to the
sample conditioning component is also required.
For wet basis systems, you must keep the sample above its dew
point either by: (1) Heating the sample line and all sample
transport components up to the inlet of the analyzer (and, for
hot-wet extractive systems, also heating the analyzer) or (2) by
diluting the sample prior to analysis using a dilution probe
system. The components required to do either of the above are
considered to be conditioning equipment.
6.2.5 Sampling Pump. For systems similar to the one shown
in Figure 7E-1, a leak-free pump is needed to pull the sample gas
through the system at a flow rate sufficient to minimize the
response time of the measurement system. The pump may be
constructed of any material that is non-reactive to the gas being
sampled. For dilution-type measurement systems, an ejector pump
(eductor) is used to create a vacuum that draws the sample through
a critical orifice at a constant rate.
6.2.6 Calibration Gas Manifold. Prepare a system to allow
the introduction of calibration gases either directly to the gas
analyzer in direct calibration mode or into the measurement system,
at the probe, in system calibration mode, or both, depending upon
the type of system used. In system calibration mode, the system
should be able to flood the sampling probe and vent excess gas.
Alternatively, calibration gases may be introduced at the
calibration valve following the probe. Maintain a constant pressure
in the gas manifold. For in-stack dilution-type systems, a gas
dilution subsystem is required to transport large volumes of
purified air to the sample probe and a probe controller is needed
to maintain the proper dilution ratio.
6.2.7 Sample Gas Manifold. For the type of system shown
in Figure 7E-1, the sample gas manifold diverts a portion of the
sample to the analyzer, delivering the remainder to the by-pass
discharge vent. The manifold should also be able to introduce
calibration gases directly to the analyzer (except for
dilution-type systems). The manifold must be made of material that
is non-reactive to the gas sampled or the calibration gas and be
configured to safely discharge the bypass gas.
6.2.8 NOX Analyzer. An instrument that
continuously measures NOX in the gas stream and meets the
applicable specifications in section 13.0. An analyzer that
operates on the principle of chemiluminescence with an NO2 to NO
converter is one example of an analyzer that has been used
successfully in the past. Analyzers operating on other principles
may also be used provided the performance criteria in section 13.0
are met.
6.2.8.1 Dual Range Analyzers. For certain applications, a
wide range of gas concentrations may be encountered, necessitating
the use of two measurement ranges. Dual-range analyzers are readily
available for these applications. These analyzers are often
equipped with automated range-switching capability, so that when
readings exceed the full-scale of the low measurement range, they
are recorded on the high range. As an alternative to using a
dual-range analyzer, you may use two segments of a single, large
measurement scale to serve as the low and high ranges. In all
cases, when two ranges are used, you must quality-assure both
ranges using the proper sets of calibration gases. You must also
meet the interference, calibration error, system bias, and drift
checks. However, we caution that when you use two segments of a
large measurement scale for dual range purposes, it may be
difficult to meet the performance specifications on the low range
due to signal-to-noise ratio considerations.
6.2.8.2 Low Concentration Analyzer. When an analyzer is
routinely calibrated with a calibration span of 20 ppmv or less,
the manufacturer's stability test (MST) is required. See Table 7E-5
for test parameters.
6.2.9 Data Recording. A strip chart recorder,
computerized data acquisition system, digital recorder, or data
logger for recording measurement data may be used.
7.0 Reagents and Standards
7.1 Calibration Gas. What calibration gases do I need?
Your calibration gas must be NO in N2 and certified (or
recertified) within an uncertainty of 2.0 percent in accordance
with “EPA Traceability Protocol for Assay and Certification of
Gaseous Calibration Standards” September 1997, as amended August
25, 1999, EPA-600/R-97/121. Blended gases meeting the Traceability
Protocol are allowed if the additional gas components are shown not
to interfere with the analysis. If a zero gas is used for the
low-level gas, it must meet the requirements under the definition
for “zero air material” in 40 CFR 72.2. The calibration gas must
not be used after its expiration date. Except for applications
under part 75 of this chapter, it is acceptable to prepare
calibration gas mixtures from EPA Traceability Protocol gases in
accordance with Method 205 in appendix M to part 51 of this
chapter. For part 75 applications, the use of Method 205 is subject
to the approval of the Administrator. The goal and recommendation
for selecting calibration gases is to bracket the sample
concentrations. The following calibration gas concentrations are
required:
7.1.1 High-Level Gas. This concentration is chosen to set
the calibration span as defined in Section 3.4.
7.1.2 Mid-Level Gas. 40 to 60 percent of the calibration
span.
7.1.3 Low-Level Gas. Less than 20 percent of the
calibration span.
7.1.4 Converter Efficiency Gas. What reagents do I need for
the converter efficiency test? The converter efficiency gas is
a manufacturer-certified gas with a concentration sufficient to
show NO2 conversion at the concentrations encountered in the
source. A test gas concentration in the 40 to 60 ppm range is
suggested, but other concentrations may be more appropriate to
specific sources. For the test described in section 8.2.4.1, NO2 is
required. For the alternative converter efficiency tests in section
16.2, NO is required.
7.2 Interference Check. What reagents do I need for the
interference check? Use the appropriate test gases listed in
Table 7E-3 or others not listed that can potentially interfere (as
indicated by the test facility type, instrument manufacturer, etc.)
to conduct the interference check. These gases should be
manufacturer certified but do not have to be prepared by the EPA
traceability protocol.
8.0 Sample Collection, Preservation, Storage, and Transport
Emission Test Procedure
Since you are allowed to choose different options to comply with
some of the performance criteria, it is your responsibility to
identify the specific options you have chosen, to document that the
performance criteria for that option have been met, and to identify
any deviations from the method.
8.1 What sampling site and sampling points do I
select?
8.1.1 Unless otherwise specified in an applicable regulation or
by the Administrator, when this method is used to determine
compliance with an emission standard, conduct a stratification test
as described in section 8.1.2 to determine the sampling traverse
points to be used. For performance testing of continuous emission
monitoring systems, follow the sampling site selection and traverse
point layout procedures described in the appropriate performance
specification or applicable regulation (e.g., Performance
Specification 2 in appendix B to this part).
8.1.2 Determination of Stratification. Perform a stratification
test at each test site to determine the appropriate number of
sample traverse points. If testing for multiple pollutants or
diluents at the same site, a stratification test using only one
pollutant or diluent satisfies this requirement. A stratification
test is not required for small stacks that are less than 4 inches
in diameter. To test for stratification, use a probe of appropriate
length to measure the NOX (or pollutant of interest) concentration
at 12 traverse points located according to Table 1-1 or Table 1-2
of Method 1. Alternatively, you may measure at three points on a
line passing through the centroidal area. Space the three points at
16.7, 50.0, and 83.3 percent of the measurement line. Sample for a
minimum of twice the system response time (see section 8.2.6) at
each traverse point. Calculate the individual point and mean NOX
concentrations. If the concentration at each traverse point differs
from the mean concentration for all traverse points by no more
than: ±5.0 percent of the mean concentration; or ±0.5 ppm
(whichever is less restrictive), the gas stream is considered
unstratified, and you may collect samples from a single point that
most closely matches the mean. If the 5.0 percent or 0.5 ppm
criterion is not met, but the concentration at each traverse point
differs from the mean concentration for all traverse points by not
more than: ±10.0 percent of the mean concentration; or ±1.0 ppm
(whichever is less restrictive), the gas stream is considered to be
minimally stratified and you may take samples from three points.
Space the three points at 16.7, 50.0, and 83.3 percent of the
measurement line. Alternatively, if a 12-point stratification test
was performed and the emissions were shown to be minimally
stratified (all points within ± 10.0 percent of their mean or
within ±1.0 ppm), and if the stack diameter (or equivalent
diameter, for a rectangular stack or duct) is greater than 2.4
meters (7.8 ft), then you may use 3-point sampling and locate the
three points along the measurement line exhibiting the highest
average concentration during the stratification test at 0.4, 1.2
and 2.0 meters from the stack or duct wall. If the gas stream is
found to be stratified because the 10.0 percent or 1.0 ppm
criterion for a 3-point test is not met, locate 12 traverse points
for the test in accordance with Table 1-1 or Table 1-2 of Method
1.
8.2 Initial Measurement System Performance Tests. What
initial performance criteria must my system meet before I begin
collecting samples? Before measuring emissions, perform the
following procedures:
(a) Calibration gas verification,
(b) Measurement system preparation,
(c) Calibration error test,
(d) NO2 to NO conversion efficiency test, if applicable,
(e) System bias check,
(f) System response time test, and
(g) Interference check
8.2.1 Calibration Gas Verification. How must I verify the
concentrations of my calibration gases? Obtain a certificate from
the gas manufacturer documenting the quality of the gas. Confirm
that the manufacturer certification is complete and current. Ensure
that your calibration gas certifications have not expired. This
documentation should be available on-site for inspection. To the
extent practicable, select a high-level gas concentration that will
result in the measured emissions being between 20 and 100 percent
of the calibration span.
8.2.2 Measurement System Preparation. How do I prepare my
measurement system? Assemble, prepare, and precondition the
measurement system according to your standard operating procedure.
Adjust the system to achieve the correct sampling rate or dilution
ratio (as applicable).
8.2.3 Calibration Error Test. How do I confirm my analyzer
calibration is correct? After you have assembled, prepared and
calibrated your sampling system and analyzer, you must conduct a
3-point analyzer calibration error test (or a 3-point system
calibration error test for dilution systems) before the first run
and again after any failed system bias test (or 2-point system
calibration error test for dilution systems) or failed drift test.
Introduce the low-, mid-, and high-level calibration gases
sequentially. For non-dilution-type measurement systems, introduce
the gases in direct calibration mode. For dilution-type measurement
systems, introduce the gases in system calibration mode.
(1) For non-dilution systems, you may adjust the system to
maintain the correct flow rate at the analyzer during the test, but
you may not make adjustments for any other purpose. For dilution
systems, you must operate the measurement system at the appropriate
dilution ratio during all system calibration error checks, and may
make only the adjustments necessary to maintain the proper
ratio.
(2) Record the analyzer's response to each calibration gas on a
form similar to Table 7E-1. For each calibration gas, calculate the
analyzer calibration error using Equation 7E-1 in section 12.2 or
the system calibration error using Equation 7E-3 in section 12.4
(as applicable). The calibration error specification in section
13.1 must be met for the low-, mid-, and high-level gases. If the
calibration error specification is not met, take corrective action
and repeat the test until an acceptable 3-point calibration is
achieved.
8.2.4 NO2 to NO Conversion Efficiency Test. Before
or after each field test, you must conduct an NO2 to NO conversion
efficiency test if your system converts NO2 to NO before analyzing
for NOX. You may risk testing multiple facilities before performing
this test provided you pass this test at the conclusion of the
final facility test. A failed final conversion efficiency test in
this case will invalidate all tests performed subsequent to the
test in which the converter efficiency test was passed. Follow the
procedures in section 8.2.4.1, or 8.2.4.2. If desired, the
converter efficiency factor derived from this test may be used to
correct the test results for converter efficiency if the NO2
fraction in the measured test gas is known. Use Equation 7E-8 in
section 12.8 for this correction.
8.2.4.1 Introduce NO2 converter efficiency gas to the analyzer
in direct calibration mode and record the NOX concentration
displayed by the analyzer. Calculate the converter efficiency using
Equation 7E-7 in section 12.7. The specification for converter
efficiency in section 13.5 must be met. The user is cautioned that
state-of-the-art NO2 calibration gases may have limited shelf
lives, and this could affect the ability to pass the 90-percent
conversion efficiency requirement.
8.2.4.2 Alternatively, either of the procedures for determining
conversion efficiency using NO in section 16.2 may be used.
8.2.5 Initial System Bias and System Calibration Error Checks.
Before sampling begins, determine whether the high-level or
mid-level calibration gas best approximates the emissions and use
it as the upscale gas. Introduce the upscale gas at the probe
upstream of all sample conditioning components in system
calibration mode. Record the time it takes for the measured
concentration to increase to a value that is at least 95 percent or
within 0.5 ppm (whichever is less restrictive) of a stable response
for both the low-level and upscale gases. Continue to observe the
gas concentration reading until it has reached a final, stable
value. Record this value on a form similar to Table 7E-2.
(1) Next, introduce the low-level gas in system calibration mode
and record the time required for the concentration response to
decrease to a value that is within 5.0 percent or 0.5 ppm
(whichever is less restrictive) of the certified low-range gas
concentration. If the low-level gas is a zero gas, use the
procedures described above and observe the change in concentration
until the response is 0.5 ppm or 5.0 percent of the upscale gas
concentration (whichever is less restrictive).
(2) Continue to observe the low-level gas reading until it has
reached a final, stable value and record the result on a form
similar to Table 7E-2. Operate the measurement system at the normal
sampling rate during all system bias checks. Make only the
adjustments necessary to achieve proper calibration gas flow rates
at the analyzer.
(3) From these data, calculate the measurement system response
time (see section 8.2.6) and then calculate the initial system bias
using Equation 7E-2 in section 12.3. For dilution systems,
calculate the system calibration error in lieu of system bias using
equation 7E-3 in section 12.4. See section 13.2 for acceptable
performance criteria for system bias and system calibration error.
If the initial system bias (or system calibration error)
specification is not met, take corrective action. Then, you must
repeat the applicable calibration error test from section 8.2.3 and
the initial system bias (or 2-point system calibration error) check
until acceptable results are achieved, after which you may begin
sampling.
(Note: For dilution-type systems, data from the 3-point system
calibration error test described in section 8.2.3 may be used to
meet the initial 2-point system calibration error test requirement
of this section, if the calibration gases were injected as
described in this section, and if response time data were
recorded).
8.2.6 Measurement System Response Time. As described in
section 8.2.5, you must determine the measurement system response
time during the initial system bias (or 2-point system calibration
error) check. Observe the times required to achieve 95 percent of a
stable response for both the low-level and upscale gases. The
longer interval is the response time.
8.2.7 Interference Check. Conduct an interference
response test of the gas analyzer prior to its initial use in the
field. If you have multiple analyzers of the same make and model,
you need only perform this alternative interference check on one
analyzer. You may also meet the interference check requirement if
the instrument manufacturer performs this or a similar check on an
analyzer of the same make and model of the analyzer that you use
and provides you with documented results.
(1) You may introduce the appropriate interference test gases
(that are potentially encountered during a test; see examples in
Table 7E-3) into the analyzer separately or as mixtures. Test the
analyzer with the interference gas alone at the highest
concentration expected at a test source and again with the
interference gas and NOX at a representative NOX test
concentration. For analyzers measuring NOX greater than 20 ppm, use
a calibration gas with a NOX concentration of 80 to 100 ppm and set
this concentration equal to the calibration span. For analyzers
measuring less than 20 ppm NOX, select an NO concentration for the
calibration span that reflects the emission levels at the sources
to be tested, and perform the interference check at that level.
Measure the total interference response of the analyzer to these
gases in ppmv. Record the responses and determine the interference
using Table 7E-4. The specification in section 13.4 must be
met.
(2) A copy of this data, including the date completed and signed
certification, must be available for inspection at the test site
and included with each test report. This interference test is valid
for the life of the instrument unless major analytical components
(e.g., the detector) are replaced with different model
parts. If major components are replaced with different model parts,
the interference gas check must be repeated before returning the
analyzer to service. If major components are replaced, the
interference gas check must be repeated before returning the
analyzer to service. The tester must ensure that any specific
technology, equipment, or procedures that are intended to remove
interference effects are operating properly during testing.
8.3 Dilution-Type Systems - Special Considerations. When
a dilution-type measurement system is used, there are three
important considerations that must be taken into account to ensure
the quality of the emissions data. First, the critical orifice size
and dilution ratio must be selected properly so that the sample dew
point will be below the sample line and analyzer temperatures.
Second, a high-quality, accurate probe controller must be used to
maintain the dilution ratio during the test. The probe controller
should be capable of monitoring the dilution air pressure, eductor
vacuum, and sample flow rates. Third, differences between the
molecular weight of calibration gas mixtures and the stack gas
molecular weight must be addressed because these can affect the
dilution ratio and introduce measurement bias.
8.4 Sample Collection.
(1) Position the probe at the first sampling point. Purge the
system for at least two times the response time before recording
any data. Then, traverse all required sampling points, sampling at
each point for an equal length of time and maintaining the
appropriate sample flow rate or dilution ratio (as applicable). You
must record at least one valid data point per minute during the
test run.
(2) Each time the probe is removed from the stack and replaced,
you must recondition the sampling system for at least two times the
system response time prior to your next recording. If the average
of any run exceeds the calibration span value, that run is
invalid.
(3) You may satisfy the multipoint traverse requirement by
sampling sequentially using a single-hole probe or a multi-hole
probe designed to sample at the prescribed points with a flow
within 10 percent of mean flow rate. Notwithstanding, for
applications under part 75 of this chapter, the use of multi-hole
probes is subject to the approval of the Administrator.
8.5 Post-Run System Bias Check and Drift Assessment.
How do I confirm that each sample I collect is valid? After each
run, repeat the system bias check or 2-point system calibration
error check (for dilution systems) to validate the run. Do not make
adjustments to the measurement system (other than to maintain the
target sampling rate or dilution ratio) between the end of the run
and the completion of the post-run system bias or system
calibration error check. Note that for all post-run system bias or
2-point system calibration error checks, you may inject the
low-level gas first and the upscale gas last, or vice-versa. If
conducting a relative accuracy test or relative accuracy test
audit, consisting of nine runs or more, you may risk sampling for
up to three runs before performing the post-run bias or system
calibration error check provided you pass this test at the
conclusion of the group of three runs. A failed post-run bias or
system calibration error check in this case will invalidate all
runs subsequent to the last passed check. When conducting a
performance or compliance test, you must perform a post-run system
bias or system calibration error check after each individual test
run.
(1) If you do not pass the post-run system bias (or system
calibration error) check, then the run is invalid. You must
diagnose and fix the problem and pass another calibration error
test (Section 8.2.3) and system bias (or 2-point system calibration
error) check (Section 8.2.5) before repeating the run. Record the
system bias (or system calibration error) results on a form similar
to Table 7E-2.
(2) After each run, calculate the low-level and upscale drift,
using Equation 7E-4 in section 12.5. If the post-run low- and
upscale bias (or 2-point system calibration error) checks are
passed, but the low-or upscale drift exceeds the specification in
section 13.3, the run data are valid, but a 3-point calibration
error test and a system bias (or 2-point system calibration error)
check must be performed and passed before any more test runs are
done.
(3) For dilution systems, data from a 3-point system calibration
error test may be used to met the pre-run 2-point system
calibration error requirement for the first run in a test sequence.
Also, the post-run bias (or 2-point calibration error) check data
may be used as the pre-run data for the next run in the test
sequence at the discretion of the tester.
8.6 Alternative Interference and System Bias Checks (Dynamic
Spike Procedure). If I want to use the dynamic spike procedure to
validate my data, what procedure should I follow? Except for
applications under part 75 of this chapter, you may use the dynamic
spiking procedure and requirements provided in section 16.1 during
each test as an alternative to the interference check and the pre-
and post-run system bias checks. The calibration error test is
still required under this option. Use of the dynamic spiking
procedure for Part 75 applications is subject to the approval of
the Administrator.
8.7 Moisture correction. You must determine the moisture
content of the flue gas and correct the measured gas concentrations
to a dry basis using Method 4 or other appropriate methods, subject
to the approval of the Administrator, when the moisture basis (wet
or dry) of the measurements made with this method is different from
the moisture basis of either: (1) The applicable emissions limit;
or (2) the CEMS being evaluated for relative accuracy. Moisture
correction is also required if the applicable limit is in lb/mmBtu
and the moisture basis of the Method 7E NOX analyzer is different
from the moisture basis of the Method 3A diluent gas (CO2 or O2)
analyzer.
9.0 Quality Control What quality control measures must I take?
The following table is a summary of the mandatory, suggested,
and alternative quality assurance and quality control measures and
the associated frequency and acceptance criteria. All of the QC
data, along with the sample run data, must be documented and
included in the test report.
Summary Table of AQ/QC
Status
Process or element
QA/QC specification
Acceptance criteria
Checking frequency
S
Identify Data User
Regulatory Agency or other
primary end user of data
Before designing test.
S
Analyzer Design
Analyzer resolution or
sensitivity
<2.0% of full-scale
range
Manufacturer design.
M
Interference gas check
Sum of responses ≤2.5% of
calibration span Alternatively, sum of responses:
≤0.5 ppmv for calibration
spans of 5 to 10 ppmv
≤0.2 ppmv for calibration
spans <5 ppmv
See Table 7E-3
M
Calibration Gases
Traceability protocol (G1,
G2)
Valid certificate required
Uncertainty ≤2.0% of tag value
M
High-level gas
Equal to the calibration
span
Each test.
M
Mid-level gas
40 to 60% of calibration
span
Each test.
M
Low-level gas
<20% of calibration
span
Each test.
S
Data Recorder Design
Data resolution
≤0.5% of full-scale range
Manufacturer design.
S
Sample Extraction
Probe material
SS or quartz if stack >500
°F
East test.
M
Sample Extraction
Probe, filter and sample line
temperature
For dry-basis analyzers, keep
sample above the dew point by heating, prior to sample
conditioning
Each run.
For wet-basis analyzers, keep
sample above dew point at all times, by heating or dilution
S
Sample Extraction
Calibration valve
material
SS
Each test.
S
Sample Extraction
Sample pump material
Inert to sample
constituents
Each test.
S
Sample Extraction
Manifolding material
Inert to sample
constituents
Each test.
S
Moisture Removal
Equipment efficiency
<5% target compound
removal
Verified through system bias
check.
S
Particulate Removal
Filter inertness
Pass system bias check
Each bias check.
M
Analyzer & Calibration Gas
Performance
Analyzer calibration error (of
3-point system calibration error for dilution systems)
Within ±2.0 percent of the
calibration span of the analyzer for the low-, mid-, and high-level
calibration gases
Before initial run and after a
failed system bias test or drift test.
Alternative specification:
≤0.5 ppmv absolute difference
M
System Performance
System bias (or pre- and
post-run 2-point system calibration error for dilution
(Systems)
Within ±5.0% of the analyzer
calibration span for low-sacle and upscale calibration gases
Before and after each
run.
Alternative specification:
≤0.5 ppmv absolute difference
M
System Performance
System response time
Determines minimum sampling
time per point
During initial sampling system
bias test.
M
System Performance
Drift
≤3.0% of calibration span for
low-level and mid- or high-level gases
After each test run.
Alternative specification:
≤0.5 ppmv absolute difference
M
System Performance
NO2-NO conversion
efficiency
≥90% of certified test gas
concentration
Before or after each
test.
M
System Performance
Purge time
≥2 times system response
time
Before starting the first run
and when probe is removed from and re-inserted into the stack.
M
System Performance
Minimum sample time at each
point
Two times the system response
time
Each sample point.
M
System Performance
Stable sample flow rate
(surrogate for maintaining system response time)
Within 10% of flow rate
established during system response time check
Each run.
M
Sample Point Selection
Stratification test
All points within:
Prior to first run.
±5% of mean for 1-point
sampling
±10% of mean for 3-point
Alternatively, all points
within:
±0.5 ppm of mean for 1-point
sampling
±1.0 ppm of mean for 3-point
sampling
A
Multiple sample points
simultaneously
No. of openings in probe
Multi-hole probe with
verifiable constant flow through all holes within 10% of mean flow
rate (requires Administrative approval for Part 75)
Each run.
M
Data Recording
Frequency
≤1 minute average
During run.
S
Data Parameters
Sample concentration
range
All 1-minute averages within
calibration span
Each run.
M
Date Parameters
Average concentration for the
run
Run average ≤calibration
span
Each run.
S = Suggest.
M = Mandatory.
A = Alternative.
Agency.
10.0 Calibration and Standardization What measurement system
calibrations are required?
(1) The initial 3-point calibration error test as described in
section 8.2.3 and the system bias (or system calibration error)
checks described in section 8.2.5 are required and must meet the
specifications in section 13 before you start the test. Make all
necessary adjustments to calibrate the gas analyzer and data
recorder. Then, after the test commences, the system bias or system
calibration error checks described in section 8.5 are required
before and after each run. Your analyzer must be calibrated for all
species of NOX that it detects. Analyzers that measure NO and NO2
separately without using a converter must be calibrated with both
NO and NO2.
(2) You must include a copy of the manufacturer's certification
of the calibration gases used in the testing as part of the test
report. This certification must include the 13 documentation
requirements in the EPA Traceability Protocol For Assay and
Certification of Gaseous Calibration Standards, September 1997, as
amended August 25, 1999. When Method 205 is used to produce diluted
calibration gases, you must document that the specifications for
the gas dilution system are met for the test. You must also include
the date of the most recent dilution system calibration against
flow standards and the name of the person or manufacturer who
carried out the calibration in the test report.
11.0 Analytical Procedures
Because sample collection and analysis are performed together
(see section 8), additional discussion of the analytical procedure
is not necessary.
12.0 Calculations and Data Analysis
You must follow the procedures for calculations and data
analysis listed in this section.
12.1 Nomenclature. The terms used in the equations are
defined as follows:
ACE = Analyzer calibration error, percent of calibration span. BWS
= Moisture content of sample gas as measured by Method 4 or other
approved method, percent/100. CAvg = Average unadjusted gas
concentration indicated by data recorder for the test run, ppmv. CD
= Pollutant concentration adjusted to dry conditions, ppmv. CDir =
Measured concentration of a calibration gas (low, mid, or high)
when introduced in direct calibration mode, ppmv. CGas = Average
effluent gas concentration adjusted for bias, ppmv. CM = Average of
initial and final system calibration bias (or 2-point system
calibration error) check responses for the upscale calibration gas,
ppmv. CMA = Actual concentration of the upscale calibration gas,
ppmv. CNative = NOX concentration in the stack gas as calculated in
section 12.6, ppmv. CO = Average of the initial and final system
calibration bias (or 2-point system calibration error) check
responses from the low-level (or zero) calibration gas, ppmv. COA =
Actual concentration of the low-level calibration gas, ppmv. CS =
Measured concentration of a calibration gas (low, mid, or high)
when introduced in system calibration mode, ppmv. CSS =
Concentration of NOX measured in the spiked sample, ppmv. CSpike =
Concentration of NOX in the undiluted spike gas, ppmv. CCalc =
Calculated concentration of NOX in the spike gas diluted in the
sample, ppmv. CV = Manufacturer certified concentration of a
calibration gas (low, mid, or high), ppmv. CW = Pollutant
concentration measured under moist sample conditions, wet basis,
ppmv. CS = Calibration span, ppmv. D = Drift assessment, percent of
calibration span. DF = Dilution system dilution factor or spike gas
dilution factor, dimensionless. EffNO2 = NO2 to NO converter
efficiency, percent. NOXCorr = The NOX concentration corrected for
the converter efficiency, ppmv. NOXFinal = The final NOX
concentration observed during the converter efficiency test in
section 16.2.2, ppmv. NOXPeak = The highest NOX concentration
observed during the converter efficiency test in section 16.2.2,
ppmv. QSpike = Flow rate of spike gas introduced in system
calibration mode, L/min. QTotal = Total sample flow rate during the
spike test, L/min. R = Spike recovery, percent. SB = System bias,
percent of calibration span. SBi = Pre-run system bias, percent of
calibration span. SBfinal = Post-run system bias, percent of
calibration span. SCE = System calibration error, percent of
calibration span. SCEi = Pre-run system calibration error, percent
of calibration span. SCEFinal = Post-run system calibration error,
percent of calibration span.
12.2 Analyzer Calibration Error. For non-dilution
systems, use Equation 7E-1 to calculate the analyzer calibration
error for the low-, mid-, and high-level calibration gases.
12.3 System Bias. For non-dilution systems, use Equation
7E-2 to calculate the system bias separately for the low-level and
upscale calibration gases.
12.4 System Calibration Error. Use Equation 7E-3 to
calculate the system calibration error for dilution systems.
Equation 7E-3 applies to both the initial 3-point system
calibration error test and the subsequent 2-point calibration error
checks between test runs. In this equation, the term “Cs” refers to
the diluted calibration gas concentration measured by the
analyzer.
12.5 Drift Assessment. Use Equation 7E-4 to separately
calculate the low-level and upscale drift over each test run. For
dilution systems, replace “SBfinal” and “SBi” with “SCEfinal” and
“SCEi”, respectively, to calculate and evaluate drift.
12.6 Effluent Gas Concentration. For each test run,
calculate Cavg, the arithmetic average of all valid NOX
concentration values (e.g., 1-minute averages). Then adjust
the value of Cavg for bias using Equation 7E-5a if you use a
non-zero gas as your low-level calibration gas, or Equation 7E-5b
if you use a zero gas as your low-level calibration gas.
12.7 NO2 - NO Conversion Efficiency. If the NOX
converter efficiency test described in section 8.2.4.1 is
performed, calculate the efficiency using Equation 7E-7.
12.8 NO2 - NO Conversion Efficiency Correction. If desired,
calculate the total NOX concentration with a correction for
converter efficiency using Equation 7E-8.
12.9Alternative NO2 Converter Efficiency.
If the alternative procedure of section 16.2.2 is used, determine
the NOX concentration decrease from NOXPeak after the minimum
30-minute test interval using Equation 7E-9. This decrease from
NOXPeak must meet the requirement in section 13.5 for the converter
to be acceptable.
12.10 Moisture Correction. Use Equation 7E-10 if your
measurements need to be corrected to a dry basis.
12.11 Calculated Spike Gas Concentration and Spike Recovery
for the Example Alternative Dynamic Spiking Procedure in section
16.1.3. Use Equation 7E-11 to determine the calculated spike
gas concentration. Use Equation 7E-12 to calculate the spike
recovery.
13.0 Method Performance
13.1 Calibration Error. This specification is applicable
to both the analyzer calibration error and the 3-point system
calibration error tests described in section 8.2.3. At each
calibration gas level (low, mid, and high) the calibration error
must either be within ±2.0 percent of the calibration span.
Alternatively, the results are acceptable if |Cdir − Cv| or |Cs−Cv|
(as applicable) is ≤0.5 ppmv.
13.2 System Bias. This specification is applicable to
both the system bias and 2-point system calibration error tests
described in section 8.2.5 and 8.5. The pre- and post-run system
bias (or system calibration error) must be within ±5.0 percent of
the calibration span for the low-level and upscale calibration
gases. Alternatively, the results are acceptable if | Cs −Cdir | is
≤0.5 ppmv or if | Cs− Cv | is ≤0.5 ppmv (as applicable).
13.3 Drift. For each run, the low-level and upscale drift
must be less than or equal to 3.0 percent of the calibration span.
The drift is also acceptable if the pre- and post-run bias (or the
pre- and post-run system calibration error) responses do not differ
by more than 0.5 ppmv at each gas concentration (i.e. | Cs
post-run− Cs pre-run | ≤0.5 ppmv).
13.4 Interference Check. The total interference response
(i.e., the sum of the interference responses of all tested gaseous
components) must not be greater than 2.50 percent of the
calibration span for the analyzer tested. In summing the
interferences, use the larger of the absolute values obtained for
the interferent tested with and without the pollutant present. The
results are also acceptable if the sum of the responses does not
exceed 0.5 ppmv for a calibration span of 5 to 10 ppmv, or 0.2 ppmv
for a calibration span <5 ppmv.
13.5NO2 to NO Conversion Efficiency Test (as
applicable). The NO2 to NO conversion efficiency, calculated
according to Equation 7E-7, must be greater than or equal to 90
percent. The alternative conversion efficiency check, described in
section 16.2.2 and calculated according to Equation 7E-9, must not
result in a decrease from NOXPeak by more than 2.0 percent.
13.6 Alternative Dynamic Spike Procedure. Recoveries of
both pre-test spikes and post-test spikes must be within 100 ±10
percent. If the absolute difference between the calculated spike
value and measured spike value is equal to or less than 0.20 ppmv,
then the requirements of the ADSC are met.
16.1 Dynamic Spike Procedure. Except for applications
under part 75 of this chapter, you may use a dynamic spiking
procedure to validate your test data for a specific test matrix in
place of the interference check and pre- and post-run system bias
checks. For part 75 applications, use of this procedure is subject
to the approval of the Administrator. Best results are obtained for
this procedure when source emissions are steady and not varying.
Fluctuating emissions may render this alternative procedure
difficult to pass. To use this alternative, you must meet the
following requirements.
16.1.1 Procedure Documentation. You must detail the
procedure you followed in the test report, including how the spike
was measured, added, verified during the run, and calculated after
the test.
16.1.2 Spiking Procedure Requirements. The spikes must be
prepared from EPA Traceability Protocol gases. Your procedure must
be designed to spike field samples at two target levels both before
and after the test. Your target spike levels should bracket the
average sample NOX concentrations. The higher target concentration
must be less than the calibration span. You must collect at least 5
data points for each target concentration. The spiking procedure
must be performed before the first run and repeated after the last
run of the test program.
16.1.3 Example Spiking Procedure. Determine the NO
concentration needed to generate concentrations that are 50 and 150
percent of the anticipated NOX concentration in the stack at the
total sampling flow rate while keeping the spike flow rate at or
below 10 percent of this total. Use a mass flow meter (accurate
within 2.0 percent) to generate these NO spike gas concentrations
at a constant flow rate. Use Equation 7E-11 in section 12.11 to
determine the calculated spike concentration in the collected
sample.
(1) Prepare the measurement system and conduct the analyzer
calibration error test as described in sections 8.2.2 and 8.2.3.
Following the sampling procedures in section 8.1, determine the
stack NOX concentration and use this concentration as the average
stack concentration (Cavg) for the first spike level, or if
desired, for both pre-test spike levels. Introduce the first level
spike gas into the system in system calibration mode and begin
sample collection. Wait for at least two times the system response
time before measuring the spiked sample concentration. Then record
at least five successive 1-minute averages of the spiked sample
gas. Monitor the spike gas flow rate and maintain at the determined
addition rate. Average the five 1-minute averages and determine the
spike recovery using Equation 7E-12. Repeat this procedure for the
other pre-test spike level. The recovery at each level must be
within the limits in section 13.6 before proceeding with the
test.
(2) Conduct the number of runs required for the test. Then
repeat the above procedure for the post-test spike evaluation. The
last run of the test may serve as the average stack concentration
for the post-test spike test calculations. The results of the
post-test spikes must meet the limits in section 13.6.
16.2 Alternative NO2 to NO Conversion Efficiency
Procedures. You may use either of the following procedures to
determine converter efficiency in place of the procedure in section
8.2.4.1.
16.2.1 The procedure for determining conversion efficiency using
NO in 40 CFR 86.123-78.
16.2.2 Bag Procedure. Perform the analyzer calibration error
test to document the calibration (both NO and NOX modes, as
applicable). Fill a Tedlar or equivalent bag approximately half
full with either ambient air, pure oxygen, or an oxygen standard
gas with at least 19.5 percent by volume oxygen content. Fill the
remainder of the bag with mid- to high-level NO in N2 (or other
appropriate concentration) calibration gas. (Note that the
concentration of the NO standard should be sufficiently high enough
for the diluted concentration to be easily and accurately measured
on the scale used. The size of the bag should be large enough to
accommodate the procedure and time required. Verify through the
manufacturer that the Tedlar alternative is suitable for NO and
make this verifed information available for inspection.)
(1) Immediately attach the bag to the inlet of the NOX analyzer
(or external converter if used). In the case of a dilution-system,
introduce the gas at a point upstream of the dilution assembly.
Measure the NOX concentration for a period of 30 minutes. If the
NOX concentration drops more than 2 percent absolute from the peak
value observed, then the NO2 converter has failed to meet the
criteria of this test. Take corrective action. The highest NOX
value observed is considered to be NOXPeak. The final NOX value
observed is considered to be NOXfinal.
(2) [Reserved]
16.3 Manufacturer's Stability Test. A manufacturer's
stability test is required for all analyzers that routinely measure
emissions below 20 ppmv and is optional but recommended for other
analyzers. This test evaluates each analyzer model by subjecting it
to the tests listed in Table 7E-5 following procedures similar to
those in 40 CFR 53.23 for thermal stability and insensitivity to
supply voltage variations. If the analyzer will be used under
temperature conditions that are outside the test conditions in
Table B-4 of Part 53.23, alternative test temperatures that better
reflect the analyzer field environment should be used. Alternative
procedures or documentation that establish the analyzer's stability
over the appropriate line voltages and temperatures are
acceptable.
17.0 References
1. “ERA Traceability Protocol for Assay and Certification of
Gaseous Calibration Standards” September 1997 as amended,
ERA-600/R-97/121.
18.0 Tables, Diagrams, Flowcharts, and Validation Data
Table 7E-3 - Example Interference Check Gas
Concentrations
Potential
interferent gas 1
Concentrations
2 sample conditioning type
Hot wet
Dried
CO2
5 and 15%
5 and 15%
H2O
25%
1%
NO
15 ppmv
15 ppmv
NO2
15 ppmv
15 ppmv
N2O
10 ppmv
10 ppmv
CO
50 ppmv
50 ppmv
NH3
10 ppmv
10 ppmv
CH4
50 ppmv
50 ppmv
SO2
20 ppmv
20 ppmv
H2
50 ppmv
50 ppmv
HCl
10 ppmv
10 ppmv
1 Any applicable gas may be
eliminated or tested at a reduced level if the manufacturer has
provided reliable means for limiting or scrubbing that gas to a
specified level.
2 As practicable, gas
concentrations should be the highest expected at test sites.
Table 7E-4 - Interference Response Date of Test: Analyzer Type:
Model No.: Serial No: Calibration Span:
Test gas type
Concentration
(ppm)
Analyzer
response
Sum of
Responses
% of
Calibration Span
Table 7E-5 - Manufacturer Stability
Test
Test description
Acceptance criteria
(note 1)
Thermal
Stability
Temperature range when drift
does not exceed 3.0% of analyzer range over a 12-hour run when
measured with NOX present @ 80% of calibration span.
Fault
Conditions
Identify conditions which,
when they occur, result in performance which is not in compliance
with the Manufacturer's Stability Test criteria. These are to be
indicated visually or electrically to alert the operator of the
problem.
Insensitivity to
Supply Voltage Variations
±10.0% (or manufacturers
alternative) variation from nominal voltage must produce a drift of
≤2.0% of calibration span for either zero or concentration ≥80% NOX
present.
Analyzer
Calibration Error
For a low-, medium-, and
high-calibration gas, the difference between the manufacturer
certified value and the analyzer response in direct calibration
mode, no more than 2.0% of calibration span.
Note 1: If the instrument is to be used as a
Low Range analyzer, all tests must be performed at a calibration
span of 20 ppm or less.
Method 8 - Determination of Sulfuric Acid and Sulfur Dioxide
Emissions From Stationary Sources Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, Method 5,
and Method 6.
1.2 Applicability. This method is applicable for the
determination of H2SO4 (including H2SO4 mist and SO3) and gaseous
SO2 emissions from stationary sources.
Note:
Filterable particulate matter may be determined along with H2SO4
and SO2 (subject to the approval of the Administrator) by inserting
a heated glass fiber filter between the probe and isopropanol
impinger (see section 6.1.1 of Method 6). If this option is chosen,
particulate analysis is gravimetric only; sulfuric acid is not
determined separately.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
A gas sample is extracted isokinetically from the stack. The
H2SO4 and the SO2 are separated, and both fractions are measured
separately by the barium-thorin titration method.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Possible interfering agents of this method are fluorides,
free ammonia, and dimethyl aniline. If any of these interfering
agents is present (this can be determined by knowledge of the
process), alternative methods, subject to the approval of the
Administrator, are required.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Corrosive reagents. Same as Method 6, section 5.2.
6.0 Equipment and Supplies
6.1 Sample Collection. Same as Method 5, section 6.1, with the
following additions and exceptions:
6.1.1 Sampling Train. A schematic of the sampling train used in
this method is shown in Figure 8-1; it is similar to the Method 5
sampling train, except that the filter position is different, and
the filter holder does not have to be heated. See Method 5, section
6.1.1, for details and guidelines on operation and maintenance.
6.1.1.1 Probe Nozzle. Borosilicate or quartz glass with a sharp,
tapered leading edge and coupled to the probe liner using a
polytetrafluoroethylene (PTFE) or glass-lined union (e.g.,
fused silica, Slico, or equivalent). When the stack temperature
exceeds 210 °C (410 °F), a leak-free ground glass fitting or other
leak free, non-contaminating fitting must be used to couple the
nozzle to the probe liner. It is also acceptable to use a one-piece
glass nozzle/liner assembly. The angle of the taper shall be ≤30°,
and the taper shall be on the outside to preserve a constant
internal diameter. The probe nozzle shall be of the button-hook or
elbow design, unless otherwise specified by the Administrator.
Other materials of construction may be used, subject to the
approval of the Administrator. A range of nozzle sizes suitable for
isokinetic sampling should be available. Typical nozzle sizes range
from 0.32 to 1.27 cm ( 1/8 to 1/2 in) inside diameter (ID) in
increments of 0.16 cm ( 1/16 in). Larger nozzles sizes are also
available if higher volume sampling trains are used.
6.1.1.2 Probe Liner. Borosilicate or quartz glass, with a
heating system to prevent visible condensation during sampling. Do
not use metal probe liners.
6.1.1.3 Filter Holder. Borosilicate glass, with a glass frit
filter support and a silicone rubber gasket. Other gasket materials
(e.g., Teflon or Viton) may be used, subject to the approval
of the Administrator. The holder design shall provide a positive
seal against leakage from the outside or around the filter. The
filter holder shall be placed between the first and second
impingers. Do not heat the filter holder.
6.1.1.4 Impingers. Four, of the Greenburg-Smith design, as shown
in Figure 8-1. The first and third impingers must have standard
tips. The second and fourth impingers must be modified by replacing
the insert with an approximately 13-mm ( 1/2-in.) ID glass tube,
having an unconstricted tip located 13 mm ( 1/2 in.) from the
bottom of the impinger. Similar collection systems, subject to the
approval of the Administrator, may be used.
6.1.1.5 Temperature Sensor. Thermometer, or equivalent, to
measure the temperature of the gas leaving the impinger train to
within 1 °C (2 °F).
6.2 Sample Recovery. The following items are required for sample
recovery:
6.2.1 Wash Bottles. Two polyethylene or glass bottles,
500-ml.
6.2.2 Graduated Cylinders. Two graduated cylinders (volumetric
flasks may be used), 250-ml, 1-liter.
6.2.3 Storage Bottles. Leak-free polyethylene bottles, 1-liter
size (two for each sampling run).
6.2.4 Trip Balance. 500-g capacity, to measure to ±0.5 g
(necessary only if a moisture content analysis is to be done).
6.3 Analysis. The following items are required for sample
analysis:
6.3.1 Pipettes. Volumetric 10-ml, 100-ml.
6.3.2 Burette. 50-ml.
6.3.3 Erlenmeyer Flask. 250-ml (one for each sample, blank, and
standard).
6.3.4 Graduated Cylinder. 100-ml.
6.3.5 Dropping Bottle. To add indicator solution, 125-ml
size.
7.0 Reagents and Standards Note:
Unless otherwise indicated, all reagents are to conform to the
specifications established by the Committee on Analytical Reagents
of the American Chemical Society, where such specifications are
available. Otherwise, use the best available grade.
7.1 Sample Collection. The following reagents are required for
sample collection:
7.1.1 Filters and Silica Gel. Same as in Method 5, sections
7.1.1 and 7.1.2, respectively.
7.1.2 Water. Same as in Method 6, section 7.1.1.
7.1.3 Isopropanol, 80 Percent by Volume. Mix 800 ml of
isopropanol with 200 ml of water.
Note:
Check for peroxide impurities using the procedure outlined in
Method 6, section 7.1.2.1.
7.1.4 Hydrogen Peroxide (H 2O 2), 3 Percent by Volume. Dilute
100 ml of 30 percent H2O2) to 1 liter with water. Prepare fresh
daily.
7.1.5 Crushed Ice.
7.2 Sample Recovery. The reagents and standards required for
sample recovery are:
7.2.1 Water. Same as in section 7.1.2.
7.2.2 Isopropanol, 80 Percent. Same as in section 7.1.3.
7.3 Sample Analysis. Same as Method 6, section 7.3.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Pretest Preparation. Same as Method 5, section 8.1, except
that filters should be inspected but need not be desiccated,
weighed, or identified. If the effluent gas can be considered dry
(i.e., moisture-free), the silica gel need not be weighed.
8.2 Preliminary Determinations. Same as Method 5, section
8.2.
8.3 Preparation of Sampling Train. Same as Method 5, section
8.3, with the following exceptions:
8.3.1 Use Figure 8-1 instead of Figure 5-1.
8.3.2 Replace the second sentence of Method 5, section 8.3.1
with: Place 100 ml of 80 percent isopropanol in the first impinger,
100 ml of 3 percent H2O2 in both the second and third impingers;
retain a portion of each reagent for use as a blank solution. Place
about 200 g of silica gel in the fourth impinger.
8.3.3 Ignore any other statements in section 8.3 of Method 5
that are obviously not applicable to the performance of Method
8.
Note:
If moisture content is to be determined by impinger analysis,
weigh each of the first three impingers (plus absorbing solution)
to the nearest 0.5 g, and record these weights. Weigh also the
silica gel (or silica gel plus container) to the nearest 0.5 g, and
record.)
8.4 Metering System Leak-Check Procedure. Same as Method 5,
section 8.4.1.
8.5 Pretest Leak-Check Procedure. Follow the basic procedure in
Method 5, section 8.4.2, noting that the probe heater shall be
adjusted to the minimum temperature required to prevent
condensation, and also that verbage such as “* * * plugging the
inlet to the filter holder * * * ” found in section 8.4.2.2 of
Method 5 shall be replaced by “ * * * plugging the inlet to the
first impinger * * * ”. The pretest leak-check is recommended, but
is not required.
8.6 Sampling Train Operation. Follow the basic procedures in
Method 5, section 8.5, in conjunction with the following special
instructions:
8.6.1 Record the data on a sheet similar to that shown in Figure
8-2 (alternatively, Figure 5-2 in Method 5 may be used). The
sampling rate shall not exceed 0.030 m 3/min (1.0 cfm) during the
run. Periodically during the test, observe the connecting line
between the probe and first impinger for signs of condensation. If
condensation does occur, adjust the probe heater setting upward to
the minimum temperature required to prevent condensation. If
component changes become necessary during a run, a leak-check shall
be performed immediately before each change, according to the
procedure outlined in section 8.4.3 of Method 5 (with appropriate
modifications, as mentioned in section 8.5 of this method); record
all leak rates. If the leakage rate(s) exceeds the specified rate,
the tester shall either void the run or plan to correct the sample
volume as outlined in section 12.3 of Method 5. Leak-checks
immediately after component changes are recommended, but not
required. If these leak-checks are performed, the procedure in
section 8.4.2 of Method 5 (with appropriate modifications) shall be
used.
8.6.2 After turning off the pump and recording the final
readings at the conclusion of each run, remove the probe from the
stack. Conduct a post-test (mandatory) leak-check as outlined in
section 8.4.4 of Method 5 (with appropriate modifications), and
record the leak rate. If the post-test leakage rate exceeds the
specified acceptable rate, either correct the sample volume, as
outlined in section 12.3 of Method 5, or void the run.
8.6.3 Drain the ice bath and, with the probe disconnected, purge
the remaining part of the train by drawing clean ambient air
through the system for 15 minutes at the average flow rate used for
sampling.
Note:
Clean ambient air can be provided by passing air through a
charcoal filter. Alternatively, ambient air (without cleaning) may
be used.
8.7 Calculation of Percent Isokinetic. Same as Method 5, section
8.6.
8.8 Sample Recovery. Proper cleanup procedure begins as soon as
the probe is removed from the stack at the end of the sampling
period. Allow the probe to cool. Treat the samples as follows:
8.8.1 Container No. 1.
8.8.1.1 If a moisture content analysis is to be performed, clean
and weigh the first impinger (plus contents) to the nearest 0.5 g,
and record this weight.
8.8.1.2 Transfer the contents of the first impinger to a 250-ml
graduated cylinder. Rinse the probe, first impinger, all connecting
glassware before the filter, and the front half of the filter
holder with 80 percent isopropanol. Add the isopropanol rinse
solution to the cylinder. Dilute the contents of the cylinder to
225 ml with 80 percent isopropanol, and transfer the cylinder
contents to the storage container. Rinse the cylinder with 25 ml of
80 percent isopropanol, and transfer the rinse to the storage
container. Add the filter to the solution in the storage container
and mix. Seal the container to protect the solution against
evaporation. Mark the level of liquid on the container, and
identify the sample container.
8.8.2 Container No. 2.
8.8.2.1 If a moisture content analysis is to be performed, clean
and weigh the second and third impingers (plus contents) to the
nearest 0.5 g, and record the weights. Also, weigh the spent silica
gel (or silica gel plus impinger) to the nearest 0.5 g, and record
the weight.
8.8.2.2 Transfer the solutions from the second and third
impingers to a 1-liter graduated cylinder. Rinse all connecting
glassware (including back half of filter holder) between the filter
and silica gel impinger with water, and add this rinse water to the
cylinder. Dilute the contents of the cylinder to 950 ml with water.
Transfer the solution to a storage container. Rinse the cylinder
with 50 ml of water, and transfer the rinse to the storage
container. Mark the level of liquid on the container. Seal and
identify the sample container.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
7.1.3
Isopropanol check
Ensure acceptable level of
peroxide impurities in isopropanol.
8.4, 8.5,
10.1
Sampling equipment leak-check
and calibration
Ensure accurate measurement of
stack gas flow rate, sample volume.
10.2
Barium standard solution
standardization
Ensure normality
determination.
11.2
Replicate titrations
Ensure precision of titration
determinations.
9.2 Volume Metering System Checks. Same as Method 5, section
9.2.
10.0 Calibration and Standardization
10.1 Sampling Equipment. Same as Method 5, section 10.0.
10.2 Barium Standard Solution. Same as Method 6, section
10.5.
11.0 Analytical Procedure
11.1. Sample Loss. Same as Method 6, section 11.1.
11.2. Sample Analysis.
11.2.1 Container No. 1. Shake the container holding the
isopropanol solution and the filter. If the filter breaks up, allow
the fragments to settle for a few minutes before removing a sample
aliquot. Pipette a 100-ml aliquot of this solution into a 250-ml
Erlenmeyer flask, add 2 to 4 drops of thorin indicator, and titrate
to a pink endpoint using 0.0100 N barium standard solution. Repeat
the titration with a second aliquot of sample, and average the
titration values. Replicate titrations must agree within 1 percent
or 0.2 ml, whichever is greater.
11.2.2 Container No. 2. Thoroughly mix the solution in the
container holding the contents of the second and third impingers.
Pipette a 10-ml aliquot of sample into a 250-ml Erlenmeyer flask.
Add 40 ml of isopropanol, 2 to 4 drops of thorin indicator, and
titrate to a pink endpoint using 0.0100 N barium standard solution.
Repeat the titration with a second aliquot of sample, and average
the titration values. Replicate titrations must agree within 1
percent or 0.2 ml, whichever is greater.
11.2.3 Blanks. Prepare blanks by adding 2 to 4 drops of thorin
indicator to 100 ml of 80 percent isopropanol. Titrate the blanks
in the same manner as the samples.
12.0 Data Analysis and Calculations
Carry out calculations retaining at least one extra significant
figure beyond that of the acquired data. Round off figures after
final calculation.
12.1 Nomenclature. Same as Method 5, section 12.1, with
the following additions and exceptions:
CH2SO4 = Sulfuric acid (including SO3) concentration, g/dscm
(lb/dscf). CSO2 = Sulfur dioxide concentration, g/dscm (lb/dscf). N
= Normality of barium perchlorate titrant, meq/ml. Va = Volume of
sample aliquot titrated, 100 ml for H2SO4 and 10 ml for SO2. Vsoln
= Total volume of solution in which the sample is contained, 1000
ml for the SO2 sample and 250 ml for the H2SO4 sample. Vt = Volume
of barium standard solution titrant used for the sample, ml. Vtb =
Volume of barium standard solution titrant used for the blank, ml.
12.2 Average Dry Gas Meter Temperature and Average Orifice
Pressure Drop. See data sheet (Figure 8-2).
12.3 Dry Gas Volume. Same as Method 5, section 12.3.
12.4 Volume of Water Vapor Condensed and Moisture Content.
Calculate the volume of water vapor using Equation 5-2 of Method 5;
the weight of water collected in the impingers and silica gel can
be converted directly to milliliters (the specific gravity of water
is 1 g/ml). Calculate the moisture content of the stack gas (Bws)
using Equation 5-3 of Method 5. The note in section 12.5 of Method
5 also applies to this method. Note that if the effluent gas stream
can be considered dry, the volume of water vapor and moisture
content need not be calculated.
Where: K3 = 0.04904 g/meq for metric units, K3
= 1.081 × 10−4 lb/meq for English units.
12.6 Sulfur Dioxide Concentration.
Where: K4 = 0.03203 g/meq for metric units, K4
= 7.061 × 10−5 lb/meq for English units.
12.7 Isokinetic Variation. Same as Method 5, section 12.11.
12.8 Stack Gas Velocity and Volumetric Flow Rate. Calculate the
average stack gas velocity and volumetric flow rate, if needed,
using data obtained in this method and the equations in sections
12.6 and 12.7 of Method 2.
13.0 Method Performance
13.1 Analytical Range. Collaborative tests have shown that the
minimum detectable limits of the method are 0.06 mg/m 3 (4 × 10−9
lb/ft 3) for H2SO4 and 1.2 mg/m 3 (74 × 10−9 lb/ft 3) for SO2. No
upper limits have been established. Based on theoretical
calculations for 200 ml of 3 percent H2O2 solution, the upper
concentration limit for SO2 in a 1.0 m 3 (35.3 ft 3) gas sample is
about 12,000 mg/m 3 (7.7 × 10−4 lb/ft 3). The upper limit can be
extended by increasing the quantity of peroxide solution in the
impingers.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 9 - Visual
Determination of the Opacity of Emissions From Stationary Sources
Many stationary sources discharge visible emissions into the
atmosphere; these emissions are usually in the shape of a plume.
This method involves the determination of plume opacity by
qualified observers. The method includes procedures for the
training and certification of observers, and procedures to be used
in the field for determination of plume opacity. The appearance of
a plume as viewed by an observer depends upon a number of
variables, some of which may be controllable and some of which may
not be controllable in the field. Variables which can be controlled
to an extent to which they no longer exert a significant influence
upon plume appearance include: Angle of the observer with respect
to the plume; angle of the observer with respect to the sun; point
of observation of attached and detached steam plume; and angle of
the observer with respect to a plume emitted from a rectangular
stack with a large length to width ratio. The method includes
specific criteria applicable to these variables.
Other variables which may not be controllable in the field are
luminescence and color contrast between the plume and the
background against which the plume is viewed. These variables exert
an influence upon the appearance of a plume as viewed by an
observer, and can affect the ability of the observer to accurately
assign opacity values to the observed plume. Studies of the theory
of plume opacity and field studies have demonstrated that a plume
is most visible and presents the greatest apparent opacity when
viewed against a contrasting background. It follows from this, and
is confirmed by field trials, that the opacity of a plume, viewed
under conditions where a contrasting background is present can be
assigned with the greatest degree of accuracy. However, the
potential for a positive error is also the greatest when a plume is
viewed under such contrasting conditions. Under conditions
presenting a less contrasting background, the apparent opacity of a
plume is less and approaches zero as the color and luminescence
contrast decrease toward zero. As a result, significant negative
bias and negative errors can be made when a plume is viewed under
less contrasting conditions. A negative bias decreases rather than
increases the possibility that a plant operator will be cited for a
violation of opacity standards due to observer error.
Studies have been undertaken to determine the magnitude of
positive errors which can be made by qualified observers while
reading plumes under contrasting conditions and using the
procedures set forth in this method. The results of these studies
(field trials) which involve a total of 769 sets of 25 readings
each are as follows:
(1) For black plumes (133 sets at a smoke generator), 100
percent of the sets were read with a positive error 1 of less than
7.5 percent opacity; 99 percent were read with a positive error of
less than 5 percent opacity.
1 For a set, positive error = average opacity determined by
observers' 25 observations - average opacity determined from
transmissometer's 25 recordings.
(2) For white plumes (170 sets at a smoke generator, 168 sets at
a coal-fired power plant, 298 sets at a sulfuric acid plant), 99
percent of the sets were read with a positive error of less than
7.5 percent opacity; 95 percent were read with a positive error of
less than 5 percent opacity.
The positive observational error associated with an average of
twenty-five readings is therefore established. The accuracy of the
method must be taken into account when determining possible
violations of applicable opacity standards.
1. Principle and Applicability
1.1 Principle. The opacity of emissions from stationary sources
is determined visually by a qualified observer.
1.2 Applicability. This method is applicable for the
determination of the opacity of emissions from stationary sources
pursuant to § 60.11(b) and for qualifying observers for visually
determining opacity of emissions.
2. Procedures
The observer qualified in accordance with section 3 of this
method shall use the following procedures for visually determining
the opacity of emissions:
2.1 Position. The qualified observer shall stand at a distance
sufficient to provide a clear view of the emissions with the sun
oriented in the 140° sector to his back. Consistent with
maintaining the above requirement, the observer shall, as much as
possible, make his observations from a position such that his line
of vision is approximately perpendicular to the plume direction,
and when observing opacity of emissions from rectangular outlets
(e.g., roof monitors, open baghouses, noncircular stacks),
approximately perpendicular to the longer axis of the outlet. The
observer's line of sight should not include more than one plume at
a time when multiple stacks are involved, and in any case the
observer should make his observations with his line of sight
perpendicular to the longer axis of such a set of multiple stacks
(e.g., stub stacks on baghouses).
2.2 Field Records. The observer shall record the name of the
plant, emission location, type facility, observer's name and
affiliation, a sketch of the observer's position relative to the
source, and the date on a field data sheet (Figure 9-1). The time,
estimated distance to the emission location, approximate wind
direction, estimated wind speed, description of the sky condition
(presence and color of clouds), and plume background are recorded
on a field data sheet at the time opacity readings are initiated
and completed.
2.3 Observations. Opacity observations shall be made at the
point of greatest opacity in that portion of the plume where
condensed water vapor is not present. The observer shall not look
continuously at the plume, but instead shall observe the plume
momentarily at 15-second intervals.
2.3.1 Attached Steam Plumes. When condensed water vapor is
present within the plume as it emerges from the emission outlet,
opacity observations shall be made beyond the point in the plume at
which condensed water vapor is no longer visible. The observer
shall record the approximate distance from the emission outlet to
the point in the plume at which the observations are made.
2.3.2 Detached Steam Plume. When water vapor in the plume
condenses and becomes visible at a distinct distance from the
emission outlet, the opacity of emissions should be evaluated at
the emission outlet prior to the condensation of water vapor and
the formation of the steam plume.
2.4 Recording Observations. Opacity observations shall be
recorded to the nearest 5 percent at 15-second intervals on an
observational record sheet. (See Figure 9-2 for an example.) A
minimum of 24 observations shall be recorded. Each momentary
observation recorded shall be deemed to represent the average
opacity of emissions for a 15-second period.
2.5 Data Reduction. Opacity shall be determined as an average of
24 consecutive observations recorded at 15-second intervals. Divide
the observations recorded on the record sheet into sets of 24
consecutive observations. A set is composed of any 24 consecutive
observations. Sets need not be consecutive in time and in no case
shall two sets overlap. For each set of 24 observations, calculate
the average by summing the opacity of the 24 observations and
dividing this sum by 24. If an applicable standard specifies an
averaging time requiring more than 24 observations, calculate the
average for all observations made during the specified time period.
Record the average opacity on a record sheet. (See Figure 9-1 for
an example.)
3. Qualifications and Testing
3.1 Certification Requirements. To receive certification as a
qualified observer, a candidate must be tested and demonstrate the
ability to assign opacity readings in 5 percent increments to 25
different black plumes and 25 different white plumes, with an error
not to exceed 15 percent opacity on any one reading and an average
error not to exceed 7.5 percent opacity in each category.
Candidates shall be tested according to the procedures described in
section 3.2. Smoke generators used pursuant to section 3.2 shall be
equipped with a smoke meter which meets the requirements of section
3.3.
The certification shall be valid for a period of 6 months, at
which time the qualification procedure must be repeated by any
observer in order to retain certification.
3.2 Certification Procedure. The certification test consists of
showing the candidate a complete run of 50 plumes - 25 black plumes
and 25 white plumes - generated by a smoke generator. Plumes within
each set of 25 black and 25 white runs shall be presented in random
order. The candidate assigns an opacity value to each plume and
records his observation on a suitable form. At the completion of
each run of 50 readings, the score of the candidate is determined.
If a candidate fails to qualify, the complete run of 50 readings
must be repeated in any retest. The smoke test may be administered
as part of a smoke school or training program, and may be preceded
by training or familiarization runs of the smoke generator during
which candidates are shown black and white plumes of known
opacity.
3.3 Smoke Generator Specifications. Any smoke generator used for
the purposes of section 3.2 shall be equipped with a smoke meter
installed to measure opacity across the diameter of the smoke
generator stack. The smoke meter output shall display instack
opacity based upon a pathlength equal to the stack exit diameter,
on a full 0 to 100 percent chart recorder scale. The smoke meter
optical design and performance shall meet the specifications shown
in Table 9-1. The smoke meter shall be calibrated as prescribed in
section 3.3.1 prior to the conduct of each smoke reading test. At
the completion of each test, the zero and span drift shall be
checked and if the drift exceeds ±1 percent opacity, the condition
shall be corrected prior to conducting any subsequent test runs.
The smoke meter shall be demonstrated, at the time of installation,
to meet the specifications listed in Table 9-1. This demonstration
shall be repeated following any subsequent repair or replacement of
the photocell or associated electronic circuitry including the
chart recorder or output meter, or every 6 months, whichever occurs
first.
Table 9-1 - Smoke Meter Design and
Performance Specifications
Parameter
Specification
a. Light
source
Incandescent lamp operated at
nominal rated voltage.
b. Spectral
response of photocell
Photopic (daylight spectral
response of the human eye - Citation 3).
c. Angle of
view
15° maximum total angle.
d. Angle of
projection
15° maximum total angle.
e. Calibration
error
±3% opacity, maximum.
f. Zero and span
drift
±1% opacity, 30 minutes.
g. Response
time
5 seconds.
3.3.1 Calibration. The smoke meter is calibrated after allowing
a minimum of 30 minutes warmup by alternately producing simulated
opacity of 0 percent and 100 percent. When stable response at 0
percent or 100 percent is noted, the smoke meter is adjusted to
produce an output of 0 percent or 100 percent, as appropriate. This
calibration shall be repeated until stable 0 percent and 100
percent readings are produced without adjustment. Simulated 0
percent and 100 percent opacity values may be produced by
alternately switching the power to the light source on and off
while the smoke generator is not producing smoke.
3.3.2 Smoke Meter Evaluation. The smoke meter design and
performance are to be evaluated as follows:
3.3.2.1 Light Source. Verify from manufacturer's data and from
voltage measurements made at the lamp, as installed, that the lamp
is operated within ±5 percent of the nominal rated voltage.
3.3.2.2 Spectral Response of Photocell. Verify from
manufacturer's data that the photocell has a photopic response;
i.e., the spectral sensitivity of the cell shall closely
approximate the standard spectral-luminosity curve for photopic
vision which is referenced in (b) of Table 9-1.
Figure 9-2 - Observation Record
Page __ of __
Company
Observer
Location
Type facility
Test Number
Point of emissions
Date
Hr.
Min.
Seconds
Steam plume
(check if applicable)
Comments
0
15
30
45
Attached
Detached
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
Figure 9-2 - Observation Record
(Continued)
Page __ of __
Company
Observer
Location
Type facility
Test Number
Point of emissions
Date
Hr.
Min.
Seconds
Steam plume
(check if applicable)
Comments
0
15
30
45
Attached
Detached
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
3.3.2.3 Angle of View. Check construction geometry to ensure
that the total angle of view of the smoke plume, as seen by the
photocell, does not exceed 15°. The total angle of view may be
calculated from: θ = 2 tan−1d/2L, where θ = total angle of view; d
= the sum of the photocell diameter + the diameter of the limiting
aperture; and L = the distance from the photocell to the limiting
aperture. The limiting aperture is the point in the path between
the photocell and the smoke plume where the angle of view is most
restricted. In smoke generator smoke meters this is normally an
orifice plate.
3.3.2.4 Angle of Projection. Check construction geometry to
ensure that the total angle of projection of the lamp on the smoke
plume does not exceed 15°. The total angle of projection may be
calculated from: θ = 2 tan−1d/2L, where θ = total angle of
projection; d = the sum of the length of the lamp filament + the
diameter of the limiting aperture; and L = the distance from the
lamp to the limiting aperture.
3.3.2.5 Calibration Error. Using neutral-density filters of
known opacity, check the error between the actual response and the
theoretical linear response of the smoke meter. This check is
accomplished by first calibrating the smoke meter according to
3.3.1 and then inserting a series of three neutral-density filters
of nominal opacity of 20, 50, and 75 percent in the smoke meter
pathlength. Filters calibrated within ±2 percent shall be used.
Care should be taken when inserting the filters to prevent stray
light from affecting the meter. Make a total of five nonconsecutive
readings for each filter. The maximum error on any one reading
shall be 3 percent opacity.
3.3.2.6 Zero and Span Drift. Determine the zero and span drift
by calibrating and operating the smoke generator in a normal manner
over a 1-hour period. The drift is measured by checking the zero
and span at the end of this period.
3.3.2.7 Response Time. Determine the response time by producing
the series of five simulated 0 percent and 100 percent opacity
values and observing the time required to reach stable response.
Opacity values of 0 percent and 100 percent may be simulated by
alternately switching the power to the light source off and on
while the smoke generator is not operating.
4. Bibliography
1. Air Pollution Control District Rules and Regulations, Los
Angeles County Air Pollution Control District, Regulation IV,
Prohibitions, Rule 50.
2. Weisburd, Melvin I., Field Operations and Enforcement Manual
for Air, U.S. Environmental Protection Agency, Research Triangle
Park, NC. APTD-1100, August 1972, pp. 4.1-4.36.
3. Condon, E.U., and Odishaw, H., Handbook of Physics,
McGraw-Hill Co., New York, NY, 1958, Table 3.1, p. 6-52.
Alternate Method 1 - Determination of the Opacity of Emissions From
Stationary Sources Remotely by Lidar
This alternate method provides the quantitative determination of
the opacity of an emissions plume remotely by a mobile lidar system
(laser radar; Light Detection and Ranging). The method includes
procedures for the calibration of the lidar and procedures to be
used in the field for the lidar determination of plume opacity. The
lidar is used to measure plume opacity during either day or
nighttime hours because it contains its own pulsed light source or
transmitter. The operation of the lidar is not dependent upon
ambient lighting conditions (light, dark, sunny or cloudy).
The lidar mechanism or technique is applicable to measuring
plume opacity at numerous wavelengths of laser radiation. However,
the performance evaluation and calibration test results given in
support of this method apply only to a lidar that employs a ruby
(red light) laser [Reference 5.1].
1. Principle and Applicability
1.1 Principle. The opacity of visible emissions from stationary
sources (stacks, roof vents, etc.) is measured remotely by a mobile
lidar (laser radar).
1.2 Applicability. This method is applicable for the remote
measurement of the opacity of visible emissions from stationary
sources during both nighttime and daylight conditions, pursuant to
40 CFR § 60.11(b). It is also applicable for the calibration and
performance verification of the mobile lidar for the measurement of
the opacity of emissions. A performance/design specification for a
basic lidar system is also incorporated into this method.
1.3 Definitions.
Azimuth angle: The angle in the horizontal plane that designates
where the laser beam is pointed. It is measured from an arbitrary
fixed reference line in that plane.
Backscatter: The scattering of laser light in a direction
opposite to that of the incident laser beam due to reflection from
particulates along the beam's atmospheric path which may include a
smoke plume.
Backscatter signal: The general term for the lidar return signal
which results from laser light being backscattered by atmospheric
and smoke plume particulates.
Convergence distance: The distance from the lidar to the point
of overlap of the lidar receiver's field-of-view and the laser
beam.
Elevation angle: The angle of inclination of the laser beam
referenced to the horizontal plane.
Far region: The region of the atmosphere's path along the lidar
line-of-sight beyond or behind the plume being measured.
Lidar: Acronym for Light Detection and Ranging.
Lidar range: The range or distance from the lidar to a point of
interest along the lidar line-of-sight.
Near region: The region of the atmospheric path along the lidar
line-of-sight between the lidar's convergence distance and the
plume being measured.
Opacity: One minus the optical transmittance of a smoke plume,
screen target, etc.
Pick interval: The time or range intervals in the lidar
backscatter signal whose minimum average amplitude is used to
calculate opacity. Two pick intervals are required, one in the near
region and one in the far region.
Plume: The plume being measured by lidar.
Plume signal: The backscatter signal resulting from the laser
light pulse passing through a plume.
1/R 2Correction: The correction made for the systematic decrease
in lidar backscatter signal amplitude with range.
Reference signal: The backscatter signal resulting from the
laser light pulse passing through ambient air.
Sample interval: The time period between successive samples for
a digital signal or between successive measurements for an analog
signal.
Signal spike: An abrupt, momentary increase and decrease in
signal amplitude.
Source: The source being tested by lidar.
Time reference: The time (to) when the laser pulse emerges from
the laser, used as the reference in all lidar time or range
measurements.
2. Procedures
The mobile lidar calibrated in accordance with Paragraph 3 of
this method shall use the following procedures for remotely
measuring the opacity of stationary source emissions:
2.1 Lidar Position. The lidar shall be positioned at a distance
from the plume sufficient to provide an unobstructed view of the
source emissions. The plume must be at a range of at least 50
meters or three consecutive pick intervals (whichever is greater)
from the lidar's transmitter/receiver convergence distance along
the line-of-sight. The maximum effective opacity measurement
distance of the lidar is a function of local atmospheric
conditions, laser beam diameter, and plume diameter. The test
position of the lidar shall be selected so that the diameter of the
laser beam at the measurement point within the plume shall be no
larger than three-fourths the plume diameter. The beam diameter is
calculated by Equation (AM1-1):
D(lidar) = A + Rφ≤0.75 D(Plume) (AM1-1) Where: D(Plume) = diameter
of the plume (cm), φ = laser beam divergence measured in radians R
= range from the lidar to the source (cm) D(Lidar) = diameter of
the laser beam at range R (cm), A = diameter of the laser beam or
pulse where it leaves the laser. The lidar range, R, is obtained by
aiming and firing the laser at the emissions source structure
immediately below the outlet. The range value is then determined
from the backscatter signal which consists of a signal spike
(return from source structure) and the atmospheric backscatter
signal [Reference 5.1]. This backscatter signal should be recorded.
When there is more than one source of emissions in the immediate
vicinity of the plume, the lidar shall be positioned so that the
laser beam passes through only a single plume, free from any
interference of the other plumes for a minimum of 50 meters or
three consecutive pick intervals (whichever is greater) in each
region before and beyond the plume along the line-of-sight
(determined from the backscatter signals). The lidar shall
initially be positioned so that its line-of-sight is approximately
perpendicular to the plume.
When measuring the opacity of emissions from rectangular outlets
(e.g., roof monitors, open baghouses, noncircular stacks, etc.),
the lidar shall be placed in a position so that its line-of-sight
is approximately perpendicular to the longer (major) axis of the
outlet.
2.2 Lidar Operational Restrictions. The lidar receiver shall not
be aimed within an angle of ±15° (cone angle) of the sun.
This method shall not be used to make opacity measurements if
thunderstorms, snowstorms, hail storms, high wind, high-ambient
dust levels, fog or other atmospheric conditions cause the
reference signals to consistently exceed the limits specified in
section 2.3.
2.3 Reference Signal Requirements. Once placed in its proper
position for opacity measurement, the laser is aimed and fired with
the line-of-sight near the outlet height and rotated horizontally
to a position clear of the source structure and the associated
plume. The backscatter signal obtained from this position is called
the ambient-air or reference signal. The lidar operator shall
inspect this signal [Section V of Reference 5.1] to: (1) determine
if the lidar line-of-sight is free from interference from other
plumes and from physical obstructions such as cables, power lines,
etc., for a minimum of 50 meters or three consecutive pick
intervals (whichever is greater) in each region before and beyond
the plume, and (2) obtain a qualitative measure of the homogeneity
of the ambient air by noting any signal spikes.
Should there be any signal spikes on the reference signal within
a minimum of 50 meters or three consecutive pick intervals
(whichever is greater) in each region before and beyond the plume,
the laser shall be fired three more times and the operator shall
inspect the reference signals on the display. If the spike(s)
remains, the azimuth angle shall be changed and the above
procedures conducted again. If the spike(s) disappears in all three
reference signals, the lidar line-of-sight is acceptable if there
is shot-to-shot consistency and there is no interference from other
plumes.
Shot-to-shot consistency of a series of reference signals over a
period of twenty seconds is verified in either of two ways. (1) The
lidar operator shall observe the reference signal amplitudes. For
shot-to-shot consistency the ratio of Rf to Rn [amplitudes of the
near and far region pick intervals (Section 2.6.1)] shall vary by
not more than ±6% between shots; or (2) the lidar operator shall
accept any one of the reference signals and treat the other two as
plume signals; then the opacity for each of the subsequent
reference signals is calculated (Equation AM1-2). For shot-to-shot
consistency, the opacity values shall be within ±3% of 0% opacity
and the associated So values less than or equal to 8% (full scale)
[Section 2.6].
If a set of reference signals fails to meet the requirements of
this section, then all plume signals [Section 2.4] from the last
set of acceptable reference signals to the failed set shall be
discarded.
2.3.1 Initial and Final Reference Signals. Three reference
signals shall be obtained within a 90-second time period prior to
any data run. A final set of three reference signals shall be
obtained within three (3) minutes after the completion of the same
data run.
2.3.2 Temporal Criterion for Additional Reference Signals. An
additional set of reference signals shall be obtained during a data
run if there is a change in wind direction or plume drift of 30° or
more from the direction that was prevalent when the last set of
reference signals was obtained. An additional set of reference
signals shall also be obtained if there is an increase in value of
SIn (near region standard deviation, Equation AM1-5) or SIf (far
region standard deviation, Equation AM1-6) that is greater than 6%
(full scale) over the respective values calculated from the
immediately previous plume signal, and this increase in value
remains for 30 seconds or longer. An additional set of reference
signals shall also be obtained if there is a change in amplitude in
either the near or the far region of the plume signal, that is
greater than 6% of the near signal amplitude and this change in
amplitude remains for 30 seconds or more.
2.4 Plume Signal Requirements. Once properly aimed, the lidar is
placed in operation with the nominal pulse or firing rate of six
pulses/minute (1 pulse/10 seconds). The lidar operator shall
observe the plume backscatter signals to determine the need for
additional reference signals as required by section 2.3.2. The
plume signals are recorded from lidar start to stop and are called
a data run. The length of a data run is determined by operator
discretion. Short-term stops of the lidar to record additional
reference signals do not constitute the end of a data run if plume
signals are resumed within 90 seconds after the reference signals
have been recorded, and the total stop or interrupt time does not
exceed 3 minutes.
2.4.1 Non-hydrated Plumes. The laser shall be aimed at the
region of the plume which displays the greatest opacity. The lidar
operator must visually verify that the laser is aimed clearly above
the source exit structure.
2.4.2 Hydrated Plumes. The lidar will be used to measure the
opacity of hydrated or so-called steam plumes. As listed in the
reference method, there are two types, i.e., attached and detached
steam plumes.
2.4.2.1 Attached Steam Plumes. When condensed water vapor is
present within a plume, lidar opacity measurements shall be made at
a point within the residual plume where the condensed water vapor
is no longer visible. The laser shall be aimed into the most dense
region (region of highest opacity) of the residual plume.
During daylight hours the lidar operator locates the most dense
portion of the residual plume visually. During nighttime hours a
high-intensity spotlight, night vision scope, or low light level
TV, etc., can be used as an aid to locate the residual plume. If
visual determination is ineffective, the lidar may be used to
locate the most dense region of the residual plume by repeatedly
measuring opacity, along the longitudinal axis or center of the
plume from the emissions outlet to a point just beyond the steam
plume. The lidar operator should also observe color differences and
plume reflectivity to ensure that the lidar is aimed completely
within the residual plume. If the operator does not obtain a clear
indication of the location of the residual plume, this method shall
not be used.
Once the region of highest opacity of the residual plume has
been located, aiming adjustments shall be made to the laser
line-of-sight to correct for the following: movement to the region
of highest opacity out of the lidar line-of-sight (away from the
laser beam) for more than 15 seconds, expansion of the steam plume
(air temperature lowers and/or relative humidity increases) so that
it just begins to encroach on the field-of-view of the lidar's
optical telescope receiver, or a decrease in the size of the steam
plume (air temperature higher and/or relative humidity decreases)
so that regions within the residual plume whose opacity is higher
than the one being monitored, are present.
2.4.2.2 Detached Steam Plumes. When the water vapor in a
hydrated plume condenses and becomes visible at a finite distance
from the stack or source emissions outlet, the opacity of the
emissions shall be measured in the region of the plume clearly
above the emissions outlet and below condensation of the water
vapor.
During daylight hours the lidar operators can visually determine
if the steam plume is detached from the stack outlet. During
nighttime hours a high-intensity spotlight, night vision scope, low
light level TV, etc., can be used as an aid in determining if the
steam plume is detached. If visual determination is ineffective,
the lidar may be used to determine if the steam plume is detached
by repeatedly measuring plume opacity from the outlet to the steam
plume along the plume's longitudinal axis or center line. The lidar
operator should also observe color differences and plume
reflectivity to detect a detached plume. If the operator does not
obtain a clear indication of the location of the detached plume,
this method shall not be used to make opacity measurements between
the outlet and the detached plume.
Once the determination of a detached steam plume has been
confirmed, the laser shall be aimed into the region of highest
opacity in the plume between the outlet and the formation of the
steam plume. Aiming adjustments shall be made to the lidar's
line-of-sight within the plume to correct for changes in the
location of the most dense region of the plume due to changes in
wind direction and speed or if the detached steam plume moves
closer to the source outlet encroaching on the most dense region of
the plume. If the detached steam plume should move too close to the
source outlet for the lidar to make interference-free opacity
measurements, this method shall not be used.
2.5 Field Records. In addition to the recording recommendations
listed in other sections of this method the following records
should be maintained. Each plume measured should be uniquely
identified. The name of the facility, type of facility, emission
source type, geographic location of the lidar with respect to the
plume, and plume characteristics should be recorded. The date of
the test, the time period that a source was monitored, the time (to
the nearest second) of each opacity measurement, and the sample
interval should also be recorded. The wind speed, wind direction,
air temperature, relative humidity, visibility (measured at the
lidar's position), and cloud cover should be recorded at the
beginning and end of each time period for a given source. A small
sketch depicting the location of the laser beam within the plume
should be recorded.
If a detached or attached steam plume is present at the
emissions source, this fact should be recorded. Figures AM1-I and
AM1-II are examples of logbook forms that may be used to record
this type of data. Magnetic tape or paper tape may also be used to
record data.
2.6 Opacity Calculation and Data Analysis. Referring to the
reference signal and plume signal in Figure AM1-III, the measured
opacity (Op) in percent for each lidar measurement is calculated
using Equation AM1-2. (Op = 1−Tp; Tp is the plume
transmittance.)
Where: In = near-region pick interval signal
amplitude, plume signal, 1/R 2 corrected, If = far-region pick
interval signal amplitude, plume signal, 1/R 2 corrected, Rn =
near-region pick interval signal amplitude, reference signal, 1/R 2
corrected, and Rf = far-region pick interval signal amplitude,
reference signal, 1/R 2 corrected.
The 1/R 2 correction to the plume and reference signal
amplitudes is made by multiplying the amplitude for each successive
sample interval from the time reference, by the square of the lidar
time (or range) associated with that sample interval [Reference
5.1].
The first step in selecting the pick intervals for Equation
AM1-2 is to divide the plume signal amplitude by the reference
signal amplitude at the same respective ranges to obtain a
“normalized” signal. The pick intervals selected using this
normalized signal, are a minimum of 15 m (100 nanoseconds) in
length and consist of at least 5 contiguous sample intervals. In
addition, the following criteria, listed in order of importance,
govern pick interval selection. (1) The intervals shall be in a
region of the normalized signal where the reference signal meets
the requirements of section 2.3 and is everywhere greater than
zero. (2) The intervals (near and far) with the minimum average
amplitude are chosen. (3) If more than one interval with the same
minimum average amplitude is found, the interval closest to the
plume is chosen. (4) The standard deviation, So, for the calculated
opacity shall be 8% or less. (So is calculated by Equation
AM1-7).
If So is greater than 8%, then the far pick interval shall be
changed to the next interval of minimal average amplitude. If So is
still greater than 8%, then this procedure is repeated for the far
pick interval. This procedure may be repeated once again for the
near pick interval, but if So remains greater than 8%, the plume
signal shall be discarded.
The reference signal pick intervals, Rn and Rf, must be chosen
over the same time interval as the plume signal pick intervals, In
and If, respectively [Figure AM1-III]. Other methods of selecting
pick intervals may be used if they give equivalent results.
Field-oriented examples of pick interval selection are available in
Reference 5.1.
The average amplitudes for each of the pick intervals, In, If,
Rn, Rf, shall be calculated by averaging the respective individual
amplitudes of the sample intervals from the plume signal and the
associated reference signal each corrected for 1/R 2. The amplitude
of In shall be calculated according to Equation (AM-3).
Where: Ini = the amplitude of the ith sample
interval (near-region), Σ = sum of the individual amplitudes for
the sample intervals, m = number of sample intervals in the pick
interval, and In = average amplitude of the near-region pick
interval.
Similarly, the amplitudes for If, Rn, and Rf are calculated with
the three expressions in Equation (AM1-4).
The standard deviation, SIn, of the set of amplitudes for the
near-region pick interval, In, shall be calculated using Equation
(AM1-5).
Similarly, the standard deviations SIf, SRn, and SRf are
calculated with the three expressions in Equation (AM1-6).
The standard deviation, So,
for each associated opacity value, Op, shall be calculated using
Equation (AM1-7).
The calculated values of In, If, Rn, Rf, SIn, SIf, SRn, SRf, Op,
and So should be recorded. Any plume signal with an So greater than
8% shall be discarded.
2.6.1 Azimuth Angle Correction. If the azimuth angle correction
to opacity specified in this section is performed, then the
elevation angle correction specified in section 2.6.2 shall not be
performed. When opacity is measured in the residual region of an
attached steam plume, and the lidar line-of-sight is not
perpendicular to the plume, it may be necessary to correct the
opacity measured by the lidar to obtain the opacity that would be
measured on a path perpendicular to the plume. The following
method, or any other method which produces equivalent results,
shall be used to determine the need for a correction, to calculate
the correction, and to document the point within the plume at which
the opacity was measured.
Figure AM1-IV(b) shows the geometry of the opacity correction.
L′ is the path through the plume along which the opacity
measurement is made. P′ is the path perpendicular to the plume at
the same point. The angle ε is the angle between L′ and the plume
center line. The angle (π/2-ε), is the angle between the L′ and P′.
The measured opacity, Op, measured along the path L′ shall be
corrected to obtain the corrected opacity, Opc, for the path P′,
using Equation (AM1-8).
The correction in Equation (AM1-8) shall be
performed if the inequality in Equation (AM1-9) is true.
Figure AM1-IV(a) shows the geometry used to calculate ε and the
position in the plume at which the lidar measurement is made. This
analysis assumes that for a given lidar measurement, the range from
the lidar to the plume, the elevation angle of the lidar from the
horizontal plane, and the azimuth angle of the lidar from an
arbitrary fixed reference in the horizontal plane can all be
obtained directly.
Rs =
range from lidar to source* βs = elevation angle of Rs* Rp = range
from lidar to plume at the opacity measurement point* βp =
elevation angle of Rp* Ra = range from lidar to plume at some
arbitrary point, Pa, so the drift angle of the plume can be
determined* βa = elevation angle of Ra* α = angle between Rp and Ra
R′s = projection of Rs in the horizontal plane R′p = projection of
Rp in the horizontal plane R′a = projection of Ra in the horizontal
plane ψ′ = angle between R′s and R′p* α′ = angle between R′p and
R′a* R≤ = distance from the source to the opacity measurement point
projected in the horizontal plane Rθ = distance from opacity
measurement point Pp to the point in the plume Pa.
The correction angle ε shall be determined using Equation
AM1-10.
*Obtained directly from lidar. These values should be
recorded.
Where: α = Cos−1 (Cosβp Cosβa Cosα′ + Sinβp Sinβa), and Rθ = (Rp2 +
Ra2 − 2 Rp Ra Cosα) 1/2
R≤, the distance from the source to the opacity measurement
point projected in the horizontal plane, shall be determined using
Equation AM1-11.
Where: R′s = Rs Cos βs, and R′p = Rp Cos βp. In
the special case where the plume centerline at the opacity
measurement point is horizontal, parallel to the ground, Equation
AM1-12 may be used to determine ε instead of Equation AM1-10.
Where: R″s = (R′ 2s + Rp 2Sin 2βp)1/2. If the
angle ε is such that ε≤30° or ε ≥150°, the azimuth angle correction
shall not be performed and the associated opacity value shall be
discarded.
2.6.2 Elevation Angle Correction. An individual lidar-measured
opacity, Op, shall be corrected for elevation angle if the laser
elevation or inclination angle, βp [Figure AM1-V], is greater than
or equal to the value calculated in Equation AM1-13.
The measured opacity, Op, along the lidar path
L, is adjusted to obtain the corrected opacity, Opc, for the actual
plume (horizontal) path, P, by using Equation (AM1-14).
Where: βp = lidar elevation or inclination
angle, Op = measured opacity along path L, and Opc = corrected
opacity for the actual plume thickness P.
The values for βp, Op and Opc should be recorded.
2.6.3 Determination of Actual Plume Opacity. Actual opacity of
the plume shall be determined by Equation AM1-15.
2.6.4 Calculation of Average Actual Plume Opacity. The average
of the actual plume opacity, Opa, shall be calculated as the
average of the consecutive individual actual opacity values, Opa,
by Equation AM1-16.
Where: (Opa)k = the kth actual opacity value in
an averaging interval containing n opacity values; k is a summing
index. Σ = the sum of the individual actual opacity values. n = the
number of individual actual opacity values contained in the
averaging interval. Opa = average actual opacity calculated over
the averaging interval. 3. Lidar Performance Verification
The lidar shall be subjected to two types of performance
verifications that shall be performed in the field. The annual
calibration, conducted at least once a year, shall be used to
directly verify operation and performance of the entire lidar
system. The routine verification, conducted for each emission
source measured, shall be used to insure proper performance of the
optical receiver and associated electronics.
3.1 Annual Calibration Procedures. Either a plume from a smoke
generator or screen targets shall be used to conduct this
calibration.
If the screen target method is selected, five screens shall be
fabricated by placing an opaque mesh material over a narrow frame
(wood, metal extrusion, etc.). The screen shall have a surface area
of at least one square meter. The screen material should be chosen
for precise optical opacities of about 10, 20, 40, 60, and 80%.
Opacity of each target shall be optically determined and should be
recorded. If a smoke generator plume is selected, it shall meet the
requirements of section 3.3 of Reference Method 9. This calibration
shall be performed in the field during calm (as practical)
atmospheric conditions. The lidar shall be positioned in accordance
with section 2.1.
The screen targets must be placed perpendicular to and
coincident with the lidar line-of-sight at sufficient height above
the ground (suggest about 30 ft) to avoid ground-level dust
contamination. Reference signals shall be obtained just prior to
conducting the calibration test.
The lidar shall be aimed through the center of the plume within
1 stack diameter of the exit, or through the geometric center of
the screen target selected. The lidar shall be set in operation for
a 6-minute data run at a nominal pulse rate of 1 pulse every 10
seconds. Each backscatter return signal and each respective opacity
value obtained from the smoke generator transmissometer, shall be
obtained in temporal coincidence. The data shall be analyzed and
reduced in accordance with section 2.6 of this method. This
calibration shall be performed for 0% (clean air), and at least
five other opacities (nominally 10, 20, 40, 60, and 80%).
The average of the lidar opacity values obtained during a
6-minute calibration run shall be calculated and should be
recorded. Also the average of the opacity values obtained from the
smoke generator transmissometer for the same 6-minute run shall be
calculated and should be recorded.
Alternate calibration procedures that do not meet the above
requirements but produce equivalent results may be used.
3.2 Routine Verification Procedures. Either one of two
techniques shall be used to conduct this verification. It shall be
performed at least once every 4 hours for each emission source
measured. The following parameters shall be directly verified.
1) The opacity value of 0% plus a minimum of 5 (nominally 10,
20, 40, 60, and 80%) opacity values shall be verified through the
PMT detector and data processing electronics.
2) The zero-signal level (receiver signal with no optical signal
from the source present) shall be inspected to insure that no
spurious noise is present in the signal. With the entire lidar
receiver and analog/digital electronics turned on and adjusted for
normal operating performance, the following procedures shall be
used for Techniques 1 and 2, respectively.
3.2.1 Procedure for Technique 1. This test shall be performed
with no ambient or stray light reaching the PMT detector. The
narrow band filter (694.3 nanometers peak) shall be removed from
its position in front of the PMT detector. Neutral density filters
of nominal opacities of 10, 20, 40, 60, and 80% shall be used. The
recommended test configuration is depicted in Figure AM1-VI.
The zero-signal level shall be measured and should be recorded,
as indicated in Figure AM1-VI(a). This simulated clear-air or 0%
opacity value shall be tested in using the selected light source
depicted in Figure AM1-VI(b).
The light source either shall be a continuous wave (CW) laser
with the beam mechanically chopped or a light emitting diode
controlled with a pulse generator (rectangular pulse). (A laser
beam may have to be attenuated so as not to saturate the PMT
detector). This signal level shall be measured and should be
recorded. The opacity value is calculated by taking two pick
intervals [Section 2.6] about 1 microsecond apart in time and using
Equation (AM1-2) setting the ratio Rn/Rf = 1. This calculated value
should be recorded.
The simulated clear-air signal level is also employed in the
optical test using the neutral density filters. Using the test
configuration in Figure AM1-VI(c), each neutral density filter
shall be separately placed into the light path from the light
source to the PMT detector. The signal level shall be measured and
should be recorded. The opacity value for each filter is calculated
by taking the signal level for that respective filter (If),
dividing it by the 0% opacity signal level (In) and performing the
remainder of the calculation by Equation (AM1-2) with Rn/Rf = 1.
The calculated opacity value for each filter should be
recorded.
The neutral density filters used for Technique 1 shall be
calibrated for actual opacity with accuracy of ±2% or better. This
calibration shall be done monthly while the filters are in use and
the calibrated values should be recorded.
3.2.2 Procedure for Technique 2. An optical generator (built-in
calibration mechanism) that contains a light-emitting diode (red
light for a lidar containing a ruby laser) is used. By injecting an
optical signal into the lidar receiver immediately ahead of the PMT
detector, a backscatter signal is simulated. With the entire lidar
receiver electronics turned on and adjusted for normal operating
performance, the optical generator is turned on and the simulation
signal (corrected for 1/R 2) is selected with no plume spike signal
and with the opacity value equal to 0%. This simulated clear-air
atmospheric return signal is displayed on the system's video
display. The lidar operator then makes any fine adjustments that
may be necessary to maintain the system's normal operating
range.
The opacity values of 0% and the other five values are selected
one at a time in any order. The simulated return signal data should
be recorded. The opacity value shall be calculated. This
measurement/calculation shall be performed at least three times for
each selected opacity value. While the order is not important, each
of the opacity values from the optical generator shall be verified.
The calibrated optical generator opacity value for each selection
should be recorded.
The optical generator used for Technique 2 shall be calibrated
for actual opacity with an accuracy of ±1% or better. This
calibration shall be done monthly while the generator is in use and
calibrated value should be recorded.
Alternate verification procedures that do not meet the above
requirements but produce equivalent results may be used.
3.3 Deviation. The permissible error for the annual calibration
and routine verification are:
3.3.1 Annual Calibration Deviation.
3.3.1.1 Smoke Generator. If the lidar-measured average opacity
for each data run is not within ±5% (full scale) of the respective
smoke generator's average opacity over the range of 0% through 80%,
then the lidar shall be considered out of calibration.
3.3.1.2 Screens. If the lidar-measured average opacity for each
data run is not within ±3% (full scale) of the
laboratory-determined opacity for each respective simulation screen
target over the range of 0% through 80%, then the lidar shall be
considered out of calibration.
3.3.2 Routine Verification Error. If the lidar-measured average
opacity for each neutral density filter (Technique 1) or optical
generator selection (Technique 2) is not within ±3% (full scale) of
the respective laboratory calibration value then the lidar shall be
considered non-operational.
4. Performance/Design Specification for Basic Lidar System
4.1 Lidar Design Specification. The essential components of the
basic lidar system are a pulsed laser (transmitter), optical
receiver, detector, signal processor, recorder, and an aiming
device that is used in aiming the lidar transmitter and receiver.
Figure AM1-VII shows a functional block diagram of a basic lidar
system.
4.2 Performance Evaluation Tests. The owner of a lidar system
shall subject such a lidar system to the performance verification
tests described in section 3, prior to first use of this method.
The annual calibration shall be performed for three separate,
complete runs and the results of each should be recorded. The
requirements of section 3.3.1 must be fulfilled for each of the
three runs.
Once the conditions of the annual calibration are fulfilled the
lidar shall be subjected to the routine verification for three
separate complete runs. The requirements of section 3.3.2 must be
fulfilled for each of the three runs and the results should be
recorded. The Administrator may request that the results of the
performance evaluation be submitted for review.
5. References
5.1 The Use of Lidar for Emissions Source Opacity Determination,
U.S. Environmental Protection Agency, National Enforcement
Investigations Center, Denver, CO. EPA-330/1-79-003-R, Arthur W.
Dybdahl, current edition [NTIS No. PB81-246662].
5.2 Field Evaluation of Mobile Lidar for the Measurement of
Smoke Plume Opacity, U.S. Environmental Protection Agency, National
Enforcement Investigations Center, Denver, CO. EPA/NEIC-TS-128,
February 1976.
5.3 Remote Measurement of Smoke Plume Transmittance Using Lidar,
C. S. Cook, G. W. Bethke, W. D. Conner (EPA/RTP). Applied Optics
11, pg 1742. August 1972.
5.4 Lidar Studies of Stack Plumes in Rural and Urban
Environments, EPA-650/4-73-002, October 1973.
5.5 American National Standard for the Safe Use of Lasers ANSI Z
136.1-176, March 8, 1976.
5.6 U.S. Army Technical Manual TB MED 279, Control of Hazards to
Health from Laser Radiation, February 1969.
5.7 Laser Institute of America Laser Safety Manual, 4th
Edition.
5.8 U.S. Department of Health, Education and Welfare,
Regulations for the Administration and Enforcement of the Radiation
Control for Health and Safety Act of 1968, January 1976.
5.9 Laser Safety Handbook, Alex Mallow, Leon Chabot, Van
Nostrand Reinhold Co., 1978.
Method 10 - Determination of Carbon Monoxide Emissions From
Stationary Sources (Instrumental Analyzer Procedure) 1.0 Scope and
Application What is Method 10?
Method 10 is a procedure for measuring carbon monoxide (CO) in
stationary source emissions using a continuous instrumental
analyzer. Quality assurance and quality control requirements are
included to assure that you, the tester, collect data of known
quality. You must document your adherence to these specific
requirements for equipment, supplies, sample collection and
analysis, calculations, and data analysis. This method does not
completely describe all equipment, supplies, and sampling and
analytical procedures you will need but refers to other methods for
some of the details. Therefore, to obtain reliable results, you
should also have a thorough knowledge of these additional test
methods which are found in appendix A to this part:
(a) Method 1 - Sample and Velocity Traverses for Stationary
Sources.
(b) Method 4 - Determination of Moisture Content in Stack
Gases.
(c) Method 7E - Determination of Nitrogen Oxides Emissions from
Stationary Sources (Instrumental Analyzer Procedure).
1.1 Analytes. What does this method determine? This
method measures the concentration of carbon monoxide.
Analyte
CAS No.
Sensitivity
CO
630-08-0
Typically <2% of
Calibration Span.
1.2 Applicability. When is this method required? The use
of Method 10 may be required by specific New Source Performance
Standards, State Implementation Plans, and permits where CO
concentrations in stationary source emissions must be measured,
either to determine compliance with an applicable emission standard
or to conduct performance testing of a continuous emission
monitoring system (CEMS). Other regulations may also require the
use of Method 10.
1.3 Data Quality Objectives. Refer to section 1.3 of
Method 7E.
2.0 Summary of Method
In this method, you continuously or intermittently sample the
effluent gas and convey the sample to an analyzer that measures the
concentration of CO. You must meet the performance requirements of
this method to validate your data.
3.0 Definitions
Refer to section 3.0 of Method 7E for the applicable
definitions.
4.0 Interferences
Substances having a strong absorption of infrared energy may
interfere to some extent in some analyzers. Instrumental correction
may be used to compensate for the interference. You may also use
silica gel and ascarite traps to eliminate the interferences. If
this option is used, correct the measured gas volume for the carbon
dioxide (CO2) removed in the trap.
5.0 Safety
Refer to section 5.0 of Method 7E.
6.0 Equipment and Supplies What do I need for the measurement
system?
6.1 Continuous Sampling. Figure 7E-1 of Method 7E is a
schematic diagram of an acceptable measurement system. The
components are the same as those in sections 6.1 and 6.2 of Method
7E, except that the CO analyzer described in section 6.2 of this
method must be used instead of the analyzer described in section
6.2 of Method 7E. You must follow the noted specifications in
section 6.1 of Method 7E except that the requirements to use
stainless steel, Teflon, or non-reactive glass filters do not
apply. Also, a heated sample line is not required to transport dry
gases or for systems that measure the CO concentration on a dry
basis.
6.2 Integrated Sampling.
6.2.1 Air-Cooled Condenser or Equivalent. To remove any
excess moisture.
6.2.2 Valve. Needle valve, or equivalent, to adjust flow
rate.
6.2.3 Pump. Leak-free diaphragm type, or equivalent, to
transport gas.
6.2.4 Rate Meter. Rotameter, or equivalent, to measure a
flow range from 0 to 1.0 liter per minute (0.035 cfm).
6.2.5 Flexible Bag. Tedlar, or equivalent, with a capacity of 60
to 90 liters (2 to 3 ft 3). (Verify through the manufacturer that
the Tedlar alternative is suitable for CO and make this verified
information available for inspection.) Leak-test the bag in the
laboratory before using by evacuating with a pump followed by a dry
gas meter. When the evacuation is complete, there should be no flow
through the meter.
6.2.6 Sample Tank. Stainless steel or aluminum tank equipped
with a pressure indicator with a minimum volume of 4 liters.
6.3 What analyzer must I use? You must use an instrument
that continuously measures CO in the gas stream and meets the
specifications in section 13.0. The dual-range analyzer provisions
in section 6.2.8.1 of Method 7E apply.
7.0 Reagents and Standards
7.1 Calibration Gas. What calibration gases do I need?
Refer to section 7.1 of Method 7E for the calibration gas
requirements.
7.2 Interference Check. What additional reagents do I need
for the interference check? Use the appropriate test gases
listed in Table 7E-3 of Method 7E (i.e., potential interferents, as
identified by the instrument manufacturer) to conduct the
interference check.
8.0 Sample Collection, Preservation, Storage, and Transport
Emission Test Procedure
8.1 Sampling Site and Sampling Points. You must follow
section 8.1 of Method 7E.
8.2 Initial Measurement System Performance Tests. You
must follow the procedures in section 8.2 of Method 7E. If a
dilution-type measurement system is used, the special
considerations in section 8.3 of Method 7E also apply.
8.3 Interference Check. You must follow the procedures of
section 8.2.7 of Method 7E.
8.4 Sample Collection.
8.4.1 Continuous Sampling. You must follow the procedures
of section 8.4 of Method 7E.
8.4.2 Integrated Sampling. Evacuate the flexible bag or sample
tank. Set up the equipment as shown in Figure 10-1 with the bag
disconnected. Place the probe in the stack and purge the sampling
line. Connect the bag, making sure that all connections are
leak-free. Sample at a rate proportional to the stack velocity. If
needed, the CO2 content of the gas may be determined by using the
Method 3 integrated sample procedures, or by weighing an ascarite
CO2 removal tube used and computing CO2 concentration from the gas
volume sampled and the weight gain of the tube. Data may be
recorded on a form similar to Table 10-1. If a sample tank is used
for sample collection, follow procedures similar to those in
sections 8.1.2, 8.2.3, 8.3, and 12.4 of Method 25 as appropriate to
prepare the tank, conduct the sampling, and correct the measured
sample concentration.
8.5 Post-Run System Bias Check, Drift Assessment, and
Alternative Dynamic Spike Procedure. You must follow the
procedures in sections 8.5 and 8.6 of Method 7E.
9.0 Quality Control
Follow the quality control procedures in section 9.0 of Method
7E.
10.0 Calibration and Standardization
Follow the procedures for calibration and standardization in
section 10.0 of Method 7E.
11.0 Analytical Procedures
Because sample collection and analysis are performed together
(see section 8), additional discussion of the analytical procedure
is not necessary.
12.0 Calculations and Data Analysis
You must follow the procedures for calculations and data
analysis in section 12.0 of Method 7E, as applicable, substituting
CO for NOX as applicable.
12.1 Concentration Correction for CO2 Removal.
Correct the CO concentration for CO2 removal (if applicable) using
Eq. 10-1.
Where: CAvg = Average gas concentration for the
test run, ppm. CCO stack = Average unadjusted stack gas CO
concentration indicated by the data recorder for the test run,
ppmv. FCO2 = Volume fraction of CO2 in the sample, i.e., percent
CO2 from Orsat analysis divided by 100. 13.0 Method Performance
The specifications for analyzer calibration error, system bias,
drift, interference check, and alternative dynamic spike procedure
are the same as in section 13.0 of Method 7E.
The dynamic spike procedure and the manufacturer stability test
are the same as in sections 16.1 and 16.3 of Method 7E
17.0 References
1. “EPA Traceability Protocol for Assay and Certification of
Gaseous Calibration Standards - September 1997 as amended,
EPA-600/R-97/121
18.0 Tables, Diagrams, Flowcharts, and Validation Data
Table 10-1 - Field Data
[Integrated sampling]
Location: Date:
Test:
Operator:
Clock Time
Rotameter Reading liters/min
(cfm)
Comments
Method 10A - Determination of Carbon Monoxide Emissions in
Certifying Continuous Emission Monitoring Systems at Petroleum
Refineries Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 4, and Method 5.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Carbon monoxide
(CO)
630-08-0
3 ppmv
1.2 Applicability. This method is applicable for the
determination of CO emissions at petroleum refineries. This method
serves as the reference method in the relative accuracy test for
nondispersive infrared (NDIR) CO continuous emission monitoring
systems (CEMS) that are required to be installed in petroleum
refineries on fluid catalytic cracking unit catalyst regenerators
(§ 60.105(a)(2) of this part).
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
An integrated gas sample is extracted from the stack, passed
through an alkaline permanganate solution to remove sulfur oxides
and nitrogen oxides, and collected in a Tedlar or equivalent bag.
(Verify through the manufacturer that the Tedlar alternative is
suitable for NO and make this verified information available for
inspection.) The CO concentration in the sample is measured
spectrophotometrically using the reaction of CO with
p-sulfaminobenzoic acid.
3.0 Definitions [Reserved] 4.0 Interferences
Sulfur oxides, nitric oxide, and other acid gases interfere with
the colorimetric reaction. They are removed by passing the sampled
gas through an alkaline potassium permanganate scrubbing solution.
Carbon dioxide (CO2) does not interfere, but, because it is removed
by the scrubbing solution, its concentration must be measured
independently and an appropriate volume correction made to the
sampled gas.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method. The analyzer users manual should be consulted for
specific precautions to be taken with regard to the analytical
procedure.
5.2 Corrosive reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water for at least 15 minutes. Remove
clothing under shower and decontaminate. Treat residual chemical
burns as thermal burns.
5.2.1 Sodium Hydroxide (NaOH). Causes severe damage to eyes and
skin. Inhalation causes irritation to nose, throat, and lungs.
Reacts exothermically with limited amounts of water.
6.0 Equipment and Supplies
6.1 Sample Collection. The sampling train shown in Figure 10A-1
is required for sample collection. Component parts are described
below:
6.1.1 Probe. Stainless steel, sheathed Pyrex glass, or
equivalent, equipped with a glass wool plug to remove particulate
matter.
6.1.2 Sample Conditioning System. Three Greenburg-Smith
impingers connected in series with leak-free connections.
6.1.3 Pump. Leak-free pump with stainless steel and Teflon parts
to transport sample at a flow rate of 300 ml/min (0.01 ft 3/min) to
the flexible bag.
6.1.4 Surge Tank. Installed between the pump and the rate meter
to eliminate the pulsation effect of the pump on the rate
meter.
6.1.5 Rate Meter. Rotameter, or equivalent, to measure flow rate
at 300 ml/min (0.01 ft 3/min). Calibrate according to section
10.2.
6.1.6 Flexible Bag. Tedlar, or equivalent, with a capacity of 10
liters (0.35 ft 3) and equipped with a sealing quick-connect plug.
The bag must be leak-free according to section 8.1. For protection,
it is recommended that the bag be enclosed within a rigid
container.
6.1.7 Sample Tank. Stainless steel or aluminum tank equipped
with a pressure indicator with a minimum volume of 10 liters.
6.1.8 Valves. Stainless-steel needle valve to adjust flow rate,
and stainless-steel 3-way valve, or equivalent.
6.1.9 CO2 Analyzer. Fyrite, or equivalent, to measure CO2
concentration to within 0.5 percent.
6.1.10 Volume Meter. Dry gas meter, capable of measuring the
sample volume under calibration conditions of 300 ml/min (0.01 ft
3/min) for 10 minutes.
6.1.11 Pressure Gauge. A water filled U-tube manometer, or
equivalent, of about 30 cm (12 in.) to leak-check the flexible
bag.
6.2 Sample Analysis.
6.2.1 Spectrophotometer. Single- or double-beam to measure
absorbance at 425 and 600 nm. Slit width should not exceed 20
nm.
6.2.2 Spectrophotometer Cells. 1-cm pathlength.
6.2.3 Vacuum Gauge. U-tube mercury manometer, 1 meter (39 in.),
with 1-mm divisions, or other gauge capable of measuring pressure
to within 1 mm Hg.
6.2.4 Pump. Capable of evacuating the gas reaction bulb to a
pressure equal to or less than 40 mm Hg absolute, equipped with
coarse and fine flow control valves.
6.2.5 Barometer. Mercury, aneroid, or other barometer capable of
measuring atmospheric pressure to within 1 mm Hg.
6.2.6 Reaction Bulbs. Pyrex glass, 100-ml with Teflon stopcock
(Figure 10A-2), leak-free at 40 mm Hg, designed so that 10 ml of
the colorimetric reagent can be added and removed easily and
accurately. Commercially available gas sample bulbs such as Supelco
Catalog No. 2-2161 may also be used.
6.2.7 Manifold. Stainless steel, with connections for three
reaction bulbs and the appropriate connections for the manometer
and sampling bag as shown in Figure 10A-3.
6.2.8 Pipets. Class A, 10-ml size.
6.2.9 Shaker Table. Reciprocating-stroke type such as Eberbach
Corporation, Model 6015. A rocking arm or rotary-motion type shaker
may also be used. The shaker must be large enough to accommodate at
least six gas sample bulbs simultaneously. It may be necessary to
construct a table top extension for most commercial shakers to
provide sufficient space for the needed bulbs (Figure 10A-4).
6.2.10 Valve. Stainless steel shut-off valve.
6.2.11 Analytical Balance. Capable of weighing to 0.1 mg.
7.0 Reagents and Standards
Unless otherwise indicated, all reagents shall conform to the
specifications established by the Committee on Analytical Reagents
of the American Chemical Society, where such specifications are
available; otherwise, the best available grade shall be used.
7.1 Sample Collection.
7.1.1 Water. Deionized distilled, to conform to ASTM D 1193-77
or 91, Type 3 (incorporated by reference - see § 60.17). If high
concentrations of organic matter are not expected to be present,
the potassium permanganate test for oxidizable organic matter may
be omitted.
7.1.2 Alkaline Permanganate Solution, 0.25 M KMnO4/1.5 M Sodium
Hydroxide (NaOH). Dissolve 40 g KMnO4 and 60 g NaOH in
approximately 900 ml water, cool, and dilute to 1 liter.
7.2 Sample Analysis.
7.2.1 Water. Same as in section 7.1.1.
7.2.2 1 M Sodium Hydroxide Solution. Dissolve 40 g NaOH in
approximately 900 ml of water, cool, and dilute to 1 liter.
7.2.3 0.1 M NaOH Solution. Dilute 50 ml of the 1 M NaOH solution
prepared in section 7.2.2 to 500 ml.
7.2.4 0.1 M Silver Nitrate (AgNO3) Solution. Dissolve 8.5 g
AgNO3 in water, and dilute to 500 ml.
7.2.5 0.1 M Para-Sulfaminobenzoic Acid (p-SABA) Solution.
Dissolve 10.0 g p-SABA in 0.1 M NaOH, and dilute to 500 ml with 0.1
M NaOH.
7.2.6 Colorimetric Solution. To a flask, add 100 ml of 0.1 M
p-SABA solution and 100 ml of 0.1 M AgNO3 solution. Mix, and add 50
ml of 1 M NaOH with shaking. The resultant solution should be clear
and colorless. This solution is acceptable for use for a period of
2 days.
7.2.7 Standard Gas Mixtures. Traceable to National Institute of
Standards and Technology (NIST) standards and containing between 50
and 1000 ppm CO in nitrogen. At least two concentrations are needed
to span each calibration range used (Section 10.3). The calibration
gases must be certified by the manufacturer to be within 2 percent
of the specified concentrations.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Sample Bag or Tank Leak-Checks. While a leak-check is
required after bag or sample tank use, it should also be done
before the bag or sample tank is used for sample collection. The
tank should be leak-checked according to the procedure specified in
section 8.1.2 of Method 25. The bag should be leak-checked in the
inflated and deflated condition according to the following
procedure:
8.1.1 Connect the bag to a water manometer, and pressurize the
bag to 5 to 10 cm H2O (2 to 4 in H2O). Allow the bag to stand for
60 minutes. Any displacement in the water manometer indicates a
leak.
8.1.2 Evacuate the bag with a leakless pump that is connected to
the downstream side of a flow indicating device such as a 0- to
100-ml/min rotameter or an impinger containing water. When the bag
is completely evacuated, no flow should be evident if the bag is
leak-free.
8.2 Sample Collection.
8.2.1 Evacuate and leak check the sample bag or tank as
specified in section 8.1. Assemble the apparatus as shown in Figure
10A-1. Loosely pack glass wool in the tip of the probe. Place 400
ml of alkaline permanganate solution in the first two impingers and
250 ml in the third. Connect the pump to the third impinger, and
follow this with the surge tank, rate meter, and 3-way valve. Do
not connect the bag or sample tank to the system at this time.
8.2.2 Leak-check the sampling system by plugging the probe
inlet, opening the 3-way valve, and pulling a vacuum of
approximately 250 mm Hg on the system while observing the rate
meter for flow. If flow is indicated on the rate meter, do not
proceed further until the leak is found and corrected.
8.2.3 Purge the system with sample gas by inserting the probe
into the stack and drawing the sample gas through the system at 300
ml/min ±10 percent for 5 minutes. Connect the evacuated bag or
sample tank to the system, record the starting time, and sample at
a rate of 300 ml/min for 30 minutes, or until the bag is nearly
full, or the sample tank reaches ambient pressure. Record the
sampling time, the barometric pressure, and the ambient
temperature. Purge the system as described above immediately before
each sample.
8.2.4 The scrubbing solution is adequate for removing sulfur
oxides and nitrogen oxides from 50 liters (1.8 ft 3) of stack gas
when the concentration of each is less than 1,000 ppm and the CO2
concentration is less than 15 percent. Replace the scrubber
solution after every fifth sample.
8.3 Carbon Dioxide Measurement. Measure the CO2 content in the
stack to the nearest 0.5 percent each time a CO sample is
collected. A simultaneous grab sample analyzed by the Fyrite
analyzer is acceptable.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
8.1
Sampling equipment leak-checks
and calibration
Ensure accuracy and precision
of sampling measurements.
10.3
Spectrophotometer
calibration
Ensure linearity of
spectrophotometer response to standards.
9.2 Volume Metering System Checks. Same as Method 5, section
9.2.
10.0 Calibration and Standardization Note:
Maintain a laboratory log of all calibrations.
10.1 Gas Bulb Calibration. Weigh the empty bulb to the nearest
0.1 g. Fill the bulb to the stopcock with water, and again weigh to
the nearest 0.1 g. Subtract the tare weight, and calculate the
volume in liters to three significant figures using the density of
water at the measurement temperature. Record the volume on the
bulb. Alternatively, mark an identification number on the bulb, and
record the volume in a notebook.
10.2 Rate Meter Calibration. Assemble the system as shown in
Figure 10A-1 (the impingers may be removed), and attach a volume
meter to the probe inlet. Set the rotameter at 300 ml/min, record
the volume meter reading, start the pump, and pull ambient air
through the system for 10 minutes. Record the final volume meter
reading. Repeat the procedure and average the results to determine
the volume of gas that passed through the system.
10.3 Spectrophotometer Calibration Curve.
10.3.1 Collect the standards as described in section 8.2.
Prepare at least two sets of three bulbs as standards to span the 0
to 400 or 400 to 1000 ppm range. If any samples span both
concentration ranges, prepare a calibration curve for each range
using separate reagent blanks. Prepare a set of three bulbs
containing colorimetric reagent but no CO to serve as a reagent
blank. Analyze each standard and blank according to the sample
analysis procedure of section 11.0 Reject the standard set where
any of the individual bulb absorbances differs from the set mean by
more than 10 percent.
10.3.2 Calculate the average absorbance for each set (3 bulbs)
of standards using Equation 10A-1 and Table 10A-1. Construct a
graph of average absorbance for each standard against its
corresponding concentration. Draw a smooth curve through the
points. The curve should be linear over the two concentration
ranges discussed in section 13.3.
11.0 Analytical Procedure
11.1 Assemble the system shown in Figure 10A-3, and record the
information required in Table 10A-1 as it is obtained. Pipet 10.0
ml of the colorimetric reagent into each gas reaction bulb, and
attach the bulbs to the system. Open the stopcocks to the reaction
bulbs, but leave the valve to the bag closed. Turn on the pump,
fully open the coarse-adjust flow valve, and slowly open the
fine-adjust valve until the pressure is reduced to at least 40 mm
Hg. Now close the coarse adjust valve, and observe the manometer to
be certain that the system is leak-free. Wait a minimum of 2
minutes. If the pressure has increased less than 1 mm Hg, proceed
as described below. If a leak is present, find and correct it
before proceeding further.
11.2 Record the vacuum pressure (Pv) to the nearest 1 mm Hg, and
close the reaction bulb stopcocks. Open the bag valve, and allow
the system to come to atmospheric pressure. Close the bag valve,
open the pump coarse adjust valve, and evacuate the system again.
Repeat this fill/evacuation procedure at least twice to flush the
manifold completely. Close the pump coarse adjust valve, open the
bag valve, and let the system fill to atmospheric pressure. Open
the stopcocks to the reaction bulbs, and let the entire system come
to atmospheric pressure. Close the bulb stopcocks, remove the
bulbs, record the room temperature and barometric pressure (Pbar,
to nearest mm Hg), and place the bulbs on the shaker table with
their main axis either parallel to or perpendicular to the plane of
the table top. Purge the bulb-filling system with ambient air for
several minutes between samples. Shake the samples for exactly 2
hours.
11.3 Immediately after shaking, measure the absorbance (A) of
each bulb sample at 425 nm if the concentration is less than or
equal to 400 ppm CO or at 600 nm if the concentration is above 400
ppm.
Note:
This may be accomplished with multiple bulb sets by sequentially
collecting sets and adding to the shaker at staggered intervals,
followed by sequentially removing sets from the shaker for
absorbance measurement after the two-hour designated intervals have
elapsed.
11.4 Use a small portion of the sample to rinse a
spectrophotometer cell several times before taking an aliquot for
analysis. If one cell is used to analyze multiple samples, rinse
the cell with deionized distilled water several times between
samples. Prepare and analyze standards and a reagent blank as
described in section 10.3. Use water as the reference. Reject the
analysis if the blank absorbance is greater than 0.1. All
conditions should be the same for analysis of samples and
standards. Measure the absorbances as soon as possible after
shaking is completed.
11.5 Determine the CO concentration of each bag sample using the
calibration curve for the appropriate concentration range as
discussed in section 10.3.
12.0 Calculations and Data Analysis
Carry out calculations retaining at least one extra decimal
figure beyond that of the acquired data. Round off figures after
final calculation.
12.1 Nomenclature.
A = Sample absorbance, uncorrected for the reagent blank. Ar =
Absorbance of the reagent blank. As = Average sample absorbance per
liter, units/liter. Bw = Moisture content in the bag sample. C = CO
concentration in the stack gas, dry basis, ppm. Cb = CO
concentration of the bag sample, dry basis, ppm. Cg = CO
concentration from the calibration curve, ppm. F = Volume fraction
of CO2 in the stack. n = Number of reaction bulbs used per bag
sample. Pb = Barometric pressure, mm Hg. Pv = Residual pressure in
the sample bulb after evacuation, mm Hg. Pw = Vapor pressure of H2O
in the bag (from Table 10A-2), mm Hg. Vb = Volume of the sample
bulb, liters. Vr = Volume of reagent added to the sample bulb,
0.0100 liter.
12.2 Average Sample Absorbance per Liter. Calculate As for each
gas bulb using Equation 10A-1, and record the value in Table 10A-1.
Calculate the average As for each bag sample, and compare the three
values to the average. If any single value differs by more than 10
percent from the average, reject this value, and calculate a new
average using the two remaining values.
Note:
A and Ar must be at the same wavelength.
12.3 CO Concentration in the Bag. Calculate Cb using Equations
10A-2 and 10A-3. If condensate is visible in the bag, calculate Bw
using Table 10A-2 and the temperature and barometric pressure in
the analysis room. If condensate is not visible, calculate Bw using
the temperature and barometric pressure at the sampling site.
12.4 CO Concentration in the Stack.
13.0 Method Performance
13.1 Precision. The estimated intralaboratory standard deviation
of the method is 3 percent of the mean for gas samples analyzed in
duplicate in the concentration range of 39 to 412 ppm. The
interlaboratory precision has not been established.
13.2 Accuracy. The method contains no significant biases when
compared to an NDIR analyzer calibrated with NIST standards.
13.3 Range. Approximately 3 to 1800 ppm CO. Samples having
concentrations below 400 ppm are analyzed at 425 nm, and samples
having concentrations above 400 ppm are analyzed at 600 nm.
13.4 Sensitivity. The detection limit is 3 ppmv based on a
change in concentration equal to three times the standard deviation
of the reagent blank solution.
13.5 Stability. The individual components of the colorimetric
reagent are stable for at least one month. The colorimetric reagent
must be used within two days after preparation to avoid excessive
blank correction. The samples in the bag should be stable for at
least one week if the bags are leak-free.
1. Butler, F.E., J.E. Knoll, and M.R. Midgett. Development and
Evaluation of Methods for Determining Carbon Monoxide Emissions.
U.S. Environmental Protection Agency, Research Triangle Park, N.C.
June 1985. 33 pp.
2. Ferguson, B.B., R.E. Lester, and W.J. Mitchell. Field
Evaluation of Carbon Monoxide and Hydrogen Sulfide Continuous
Emission Monitors at an Oil Refinery. U.S. Environmental Protection
Agency, Research Triangle Park, N.C. Publication No.
EPA-600/4-82-054. August 1982. 100 pp.
3. Lambert, J.L., and R.E. Weins. Induced Colorimetric Method
for Carbon Monoxide. Analytical Chemistry. 46(7):929-930.
June 1974.
4. Levaggi, D.A., and M. Feldstein. The Colorimetric
Determination of Low Concentrations of Carbon Monoxide. Industrial
Hygiene Journal. 25:64-66. January-February 1964.
5. Repp, M. Evaluation of Continuous Monitors For Carbon
Monoxide in Stationary Sources. U.S. Environmental Protection
Agency. Research Triangle Park, N.C. Publication No.
EPA-600/2-77-063. March 1977. 155 pp.
6. Smith, F., D.E. Wagoner, and R.P. Donovan. Guidelines for
Development of a Quality Assurance Program: Volume VIII -
Determination of CO Emissions from Stationary Sources by NDIR
Spectrometry. U.S. Environmental Protection Agency. Research
Triangle Park, N.C. Publication No. EPA-650/4-74-005-h. February
1975. 96 pp.
17.0 Tables, Diagrams, Flowcharts, and Validation Data
Table 10A-1 - Data Recording Sheet for
Samples Analyzed in Triplicate
Sample
No./type
Room
temp
°C
Stack
%CO2
Bulb
No.
Bulb
vol.
liters
Reagent
vol. in
bulb,
liter
Partial
pressure
of
gas in
bulb,
mm Hg
Pb,
mm Hg
Shaking
time,
min
Abs
versus
water
A-Ar
As
Avg As
blank
Std. 1
Std. 2
Sample 1
Sample 2
Sample 3
Table 10A-2 - Moisture Correction
Temperature °C
Vapor
pressure of
H2O, mm Hg
Temperature °C
Vapor
pressure of
H2, mm Hg
4
6.1
18
15.5
6
7.0
20
17.5
8
8.0
22
19.8
10
9.2
24
22.4
12
10.5
26
25.2
14
12.0
28
28.3
16
13.6
30
31.8
Method 10B -
Determination of Carbon Monoxide Emissions From Stationary Sources
Note:
This method is not inclusive with respect to specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 4, Method 10A, and Method
25.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Carbon monoxide
(CO)
630-08-0
Not determined.
1.2 Applicability. This method applies to the measurement of CO
emissions at petroleum refineries and from other sources when
specified in an applicable subpart of the regulations.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 An integrated gas sample is extracted from the sampling
point, passed through a conditioning system to remove
interferences, and collected in a Tedlar or equivalent bag. (Verify
through the manufacturer that the Tedlar alternative is suitable
for NO and make this verifying information available for
inspection.) The CO is separated from the sample by gas
chromatography (GC) and catalytically reduced to methane (CH4)
which is determined by flame ionization detection (FID). The
analytical portion of this method is identical to applicable
sections in Method 25 detailing CO measurement.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Carbon dioxide (CO2) and organics potentially can interfere
with the analysis. Most of the CO2 is removed from the sample by
the alkaline permanganate conditioning system; any residual CO2 and
organics are separated from the CO by GC.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method. The analyzer users manual should be consulted for
specific precautions concerning the analytical procedure.
6.0 Equipment and Supplies
6.1 Sample Collection. Same as in Method 10A, section 6.1
(paragraphs 6.1.1 through 6.1.11).
6.2 Sample Analysis. A GC/FID analyzer, capable of quantifying
CO in the sample and consisting of at least the following major
components, is required for sample analysis. [Alternatively,
complete Method 25 analytical systems (Method 25, section 6.3) are
acceptable alternatives when calibrated for CO and operated in
accordance with the Method 25 analytical procedures (Method 25,
section 11.0).]
6.2.1 Separation Column. A column capable of separating CO from
CO2 and organic compounds that may be present. A 3.2-mm ( 1/8-in.)
OD stainless steel column packed with 1.7 m (5.5 ft.) of 60/80 mesh
Carbosieve S-II (available from Supelco) has been used successfully
for this purpose.
6.2.2 Reduction Catalyst. Same as in Method 25, section
6.3.1.2.
6.2.3 Sample Injection System. Same as in Method 25, Section
6.3.1.4, equipped to accept a sample line from the bag.
6.2.4 Flame Ionization Detector. Meeting the linearity
specifications of section 10.3 and having a minimal instrument
range of 10 to 1,000 ppm CO.
6.2.5 Data Recording System. Analog strip chart recorder or
digital integration system, compatible with the FID, for
permanently recording the analytical results.
7.0 Reagents and Standards
7.1 Sample Collection. Same as in Method 10A, section 7.1.
7.2 Sample Analysis.
7.2.1 Carrier, Fuel, and Combustion Gases. Same as in Method 25,
sections 7.2.1, 7.2.2, and 7.2.3, respectively.
7.2.2 Calibration Gases. Three standard gases with nominal CO
concentrations of 20, 200, and 1,000 ppm CO in nitrogen. The
calibration gases shall be certified by the manufacturer to be ±2
percent of the specified concentrations.
7.2.3 Reduction Catalyst Efficiency Check Calibration Gas.
Standard CH4 gas with a nominal concentration of 1,000 ppm in
air.
8.0 Sample Collection, Preservation, Storage, and Transport
Same as in Method 10A, section 8.0.
9.0 Quality Control
Section
Quality control measure
Effect
8.0
Sample bag/sampling system
leak-checks
Ensures that negative bias
introduced through leakage is minimized.
10.1
Carrier gas blank check
Ensures that positive bias
introduced by contamination of carrier gas is less than 5
ppmv.
10.2
Reduction catalyst efficiency
check
Ensures that negative bias
introduced by inefficient reduction catalyst is less than 5
percent.
10.3
Analyzer calibration
Ensures linearity of analyzer
response to standards.
11.2
Triplicate sample
analyses
Ensures precision of
analytical results.
10.0 Calibration and Standardization
10.1 Carrier Gas Blank Check. Analyze each new tank of carrier
gas with the GC analyzer according to section 11.2 to check for
contamination. The corresponding concentration must be less than 5
ppm for the tank to be acceptable for use.
10.2 Reduction Catalyst Efficiency Check. Prior to initial use,
the reduction catalyst shall be tested for reduction efficiency.
With the heated reduction catalyst bypassed, make triplicate
injections of the 1,000 ppm CH4 gas (Section 7.2.3) to calibrate
the analyzer. Repeat the procedure using 1,000 ppm CO gas (Section
7.2.2) with the catalyst in operation. The reduction catalyst
operation is acceptable if the CO response is within 5 percent of
the certified gas value.
10.3 Analyzer Calibration. Perform this test before the system
is first placed into operation. With the reduction catalyst in
operation, conduct a linearity check of the analyzer using the
standards specified in section 7.2.2. Make triplicate injections of
each calibration gas, and then calculate the average response
factor (area/ppm) for each gas, as well as the overall mean of the
response factor values. The instrument linearity is acceptable if
the average response factor of each calibration gas is within 2.5
percent of the overall mean value and if the relative standard
deviation (calculated in section 12.8 of Method 25) for each set of
triplicate injections is less than 2 percent. Record the overall
mean of the response factor values as the calibration response
factor (R).
11.0 Analytical Procedure
11.1 Preparation for Analysis. Before putting the GC analyzer
into routine operation, conduct the calibration procedures listed
in section 10.0. Establish an appropriate carrier flow rate and
detector temperature for the specific instrument used.
11.2 Sample Analysis. Purge the sample loop with sample, and
then inject the sample. Analyze each sample in triplicate, and
calculate the average sample area (A). Determine the bag CO
concentration according to section 12.2.
12.0 Calculations and Data Analysis
Carry out calculations retaining at least one extra significant
figure beyond that of the acquired data. Round off results only
after the final calculation.
12.1 Nomenclature.
A = Average sample area. Bw = Moisture content in the bag sample,
fraction. C = CO concentration in the stack gas, dry basis, ppm. Cb
= CO concentration in the bag sample, dry basis, ppm. F = Volume
fraction of CO2 in the stack, fraction. Pbar = Barometric pressure,
mm Hg. Pw = Vapor pressure of the H2O in the bag (from Table 10A-2,
Method 10A), mm Hg. R = Mean calibration response factor, area/ppm.
12.2 CO Concentration in the Bag. Calculate Cb using Equations
10B-1 and 10B-2. If condensate is visible in the bag, calculate Bw
using Table 10A-2 of Method 10A and the temperature and barometric
pressure in the analysis room. If condensate is not visible,
calculate Bw using the temperature and barometric pressure at the
sampling site.
Same as in Method 25, section 16.0, with the addition of the
following:
1. Butler, F.E, J.E. Knoll, and M.R. Midgett. Development and
Evaluation of Methods for Determining Carbon Monoxide Emissions.
Quality Assurance Division, Environmental Monitoring Systems
Laboratory, U.S. Environmental Protection Agency, Research Triangle
Park, NC. June 1985. 33 pp.
17.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
[36 FR 24877, Dec. 23, 1971] Editorial Note:For Federal Register
citations affecting appendix A-4 to part 60, see the List of CFR
sections Affected, which appears in the Finding Aids section of the
printed volume and at www.govinfo.gov.
Appendix A-5 to Part 60 - Test Methods 11 through 15A
40:9.0.1.1.1.0.1.1.5 : Appendix A
Appendix A-5 to Part 60 - Test Methods 11 through 15A Method 11 -
Determination of hydrogen sulfide content of fuel gas streams in
petroleum refineries Method 12 - Determination of inorganic lead
emissions from stationary sources Method 13A - Determination of
total fluoride emissions from stationary sources - SPADNS zirconium
lake method Method 13B - Determination of total fluoride emissions
from stationary sources - Specific ion electrode method Method 14 -
Determination of fluoride emissions from potroom roof monitors for
primary aluminum plants Method 14A - Determination of Total
Fluoride Emissions from Selected Sources at Primary Aluminum
Production Facilities Method 15 - Determination of hydrogen
sulfide, carbonyl sulfide, and carbon disulfide emissions from
stationary sources Method 15A - Determination of total reduced
sulfur emissions from sulfur recovery plants in petroleum
refineries
The test methods in this appendix are referred to in § 60.8
(Performance Tests) and § 60.11 (Compliance With Standards and
Maintenance Requirements) of 40 CFR part 60, subpart A (General
Provisions). Specific uses of these test methods are described in
the standards of performance contained in the subparts, beginning
with Subpart D.
Within each standard of performance, a section title “Test
Methods and Procedures” is provided to: (1) Identify the test
methods to be used as reference methods to the facility subject to
the respective standard and (2) identify any special instructions
or conditions to be followed when applying a method to the
respective facility. Such instructions (for example, establish
sampling rates, volumes, or temperatures) are to be used either in
addition to, or as a substitute for procedures in a test method.
Similarly, for sources subject to emission monitoring requirements,
specific instructions pertaining to any use of a test method as a
reference method are provided in the subpart or in Appendix B.
Inclusion of methods in this appendix is not intended as an
endorsement or denial of their applicability to sources that are
not subject to standards of performance. The methods are
potentially applicable to other sources; however, applicability
should be confirmed by careful and appropriate evaluation of the
conditions prevalent at such sources.
The approach followed in the formulation of the test methods
involves specifications for equipment, procedures, and performance.
In concept, a performance specification approach would be
preferable in all methods because this allows the greatest
flexibility to the user. In practice, however, this approach is
impractical in most cases because performance specifications cannot
be established. Most of the methods described herein, therefore,
involve specific equipment specifications and procedures, and only
a few methods in this appendix rely on performance criteria.
Minor changes in the test methods should not necessarily affect
the validity of the results and it is recognized that alternative
and equivalent methods exist. section 60.8 provides authority for
the Administrator to specify or approve (1) equivalent methods, (2)
alternative methods, and (3) minor changes in the methodology of
the test methods. It should be clearly understood that unless
otherwise identified all such methods and changes must have prior
approval of the Administrator. An owner employing such methods or
deviations from the test methods without obtaining prior approval
does so at the risk of subsequent disapproval and retesting with
approved methods.
Within the test methods, certain specific equipment or
procedures are recognized as being acceptable or potentially
acceptable and are specifically identified in the methods. The
items identified as acceptable options may be used without approval
but must be identified in the test report. The potentially
approvable options are cited as “subject to the approval of the
Administrator” or as “or equivalent.” Such potentially approvable
techniques or alternatives may be used at the discretion of the
owner without prior approval. However, detailed descriptions for
applying these potentially approvable techniques or alternatives
are not provided in the test methods. Also, the potentially
approvable options are not necessarily acceptable in all
applications. Therefore, an owner electing to use such potentially
approvable techniques or alternatives is responsible for: (1)
assuring that the techniques or alternatives are in fact applicable
and are properly executed; (2) including a written description of
the alternative method in the test report (the written method must
be clear and must be capable of being performed without additional
instruction, and the degree of detail should be similar to the
detail contained in the test methods); and (3) providing any
rationale or supporting data necessary to show the validity of the
alternative in the particular application. Failure to meet these
requirements can result in the Administrator's disapproval of the
alternative.
Method 11 - Determination of Hydrogen Sulfide Content of Fuel Gas
Streams in Petroleum Refineries 1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Hydrogen sulfide
(H2S)
7783-06-4
8 mg/m 3 - 740 mg/m
3, (6 ppm - 520 ppm).
1.2 Applicability. This method is applicable for the
determination of the H2S content of fuel gas streams at petroleum
refineries.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A sample is extracted from a source and passed through a
series of midget impingers containing a cadmium sulfate (CdSO4)
solution; H2S is absorbed, forming cadmium sulfide (CdS). The
latter compound is then measured iodometrically.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Any compound that reduces iodine (I2) or oxidizes the iodide
ion will interfere in this procedure, provided it is collected in
the CdSO4 impingers. Sulfur dioxide in concentrations of up to
2,600 mg/m 3 is removed with an impinger containing a hydrogen
peroxide (H2O2) solution. Thiols precipitate with H2S. In the
absence of H2S, only traces of thiols are collected. When
methane-and ethane-thiols at a total level of 300 mg/m 3 are
present in addition to H2S, the results vary from 2 percent low at
an H2S concentration of 400 mg/m 3 to 14 percent high at an H2S
concentration of 100 mg/m 3. Carbonyl sulfide at a concentration of
20 percent does not interfere. Certain carbonyl-containing
compounds react with iodine and produce recurring end points.
However, acetaldehyde and acetone at concentrations of 1 and 3
percent, respectively, do not interfere.
4.2 Entrained H2O2 produces a negative interference equivalent
to 100 percent of that of an equimolar quantity of H2S. Avoid the
ejection of H2O2 into the CdSO4 impingers.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Corrosive reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water for at least 15 minutes. Remove
clothing under shower and decontaminate. Treat residual chemical
burns as thermal burns.
5.2.1 Hydrogen Peroxide. Irritating to eyes, skin, nose, and
lungs. 30% H2O2 is a strong oxidizing agent. Avoid contact with
skin, eyes, and combustible material. Wear gloves when
handling.
5.2.2 Hydrochloric Acid. Highly toxic. Vapors are highly
irritating to eyes, skin, nose, and lungs, causing severe damage.
May cause bronchitis, pneumonia, or edema of lungs. Exposure to
concentrations of 0.13 to 0.2 percent can be lethal in minutes.
Will react with metals, producing hydrogen.
6.0 Equipment and Supplies
6.1 Sample Collection. The following items are needed for sample
collection:
6.1.1 Sampling Line. Teflon tubing, 6- to 7- mm ( 1/4-in.) ID,
to connect the sampling train to the sampling valve.
6.1.2 Impingers. Five midget impingers, each with 30-ml
capacity. The internal diameter of the impinger tip must be 1 mm
±0.05 mm. The impinger tip must be positioned 4 to 6 mm from the
bottom of the impinger.
6.1.3 Tubing. Glass or Teflon connecting tubing for the
impingers.
6.1.4 Ice Water Bath. To maintain absorbing solution at a low
temperature.
6.1.5 Drying Tube. Tube packed with 6- to 16- mesh
indicating-type silica gel, or equivalent, to dry the gas sample
and protect the meter and pump. If the silica gel has been used
previously, dry at 175 °C (350 °F) for 2 hours. New silica gel may
be used as received. Alternatively, other types of desiccants
(equivalent or better) may be used, subject to approval of the
Administrator.
Note:
Do not use more than 30 g of silica gel. Silica gel adsorbs
gases such as propane from the fuel gas stream, and use of
excessive amounts of silica gel could result in errors in the
determination of sample volume.
6.1.6 Sampling Valve. Needle valve, or equivalent, to adjust gas
flow rate. Stainless steel or other corrosion-resistant
material.
6.1.7 Volume Meter. Dry gas meter (DGM), sufficiently accurate
to measure the sample volume within 2 percent, calibrated at the
selected flow rate (about 1.0 liter/min) and conditions actually
encountered during sampling. The meter shall be equipped with a
temperature sensor (dial thermometer or equivalent) capable of
measuring temperature to within 3 °C (5.4 °F). The gas meter should
have a petcock, or equivalent, on the outlet connector which can be
closed during the leak-check. Gas volume for one revolution of the
meter must not be more than 10 liters.
6.1.8 Rate Meter. Rotameter, or equivalent, to measure flow
rates in the range from 0.5 to 2 liters/min (1 to 4 ft 3/hr).
6.1.9 Graduated Cylinder. 25-ml size.
6.1.10 Barometer. Mercury, aneroid, or other barometer capable
of measuring atmospheric pressure to within 2.5 mm Hg (0.1 in. Hg).
In many cases, the barometric reading may be obtained from a nearby
National Weather Service station, in which case, the station value
(which is the absolute barometric pressure) shall be requested and
an adjustment for elevation differences between the weather station
and the sampling point shall be applied at a rate of minus 2.5 mm
Hg (0.1 in Hg) per 30 m (100 ft) elevation increase or vice-versa
for elevation decrease.
6.1.11 U-tube Manometer. 0-; to 30-cm water column, for
leak-check procedure.
6.1.12 Rubber Squeeze Bulb. To pressurize train for
leak-check.
6.1.13 Tee, Pinchclamp, and Connecting Tubing. For
leak-check.
6.1.14 Pump. Diaphragm pump, or equivalent. Insert a small surge
tank between the pump and rate meter to minimize the pulsation
effect of the diaphragm pump on the rate meter. The pump is used
for the air purge at the end of the sample run; the pump is not
ordinarily used during sampling, because fuel gas streams are
usually sufficiently pressurized to force sample gas through the
train at the required flow rate. The pump need not be leak-free
unless it is used for sampling.
6.1.15 Needle Valve or Critical Orifice. To set air purge flow
to 1 liter/min.
6.1.16 Tube Packed with Active Carbon. To filter air during
purge.
6.1.17 Volumetric Flask. One 1000-ml.
6.1.18 Volumetric Pipette. One 15-ml.
6.1.19 Pressure-Reduction Regulator. Depending on the sampling
stream pressure, a pressure-reduction regulator may be needed to
reduce the pressure of the gas stream entering the Teflon sample
line to a safe level.
6.1.20 Cold Trap. If condensed water or amine is present in the
sample stream, a corrosion-resistant cold trap shall be used
immediately after the sample tap. The trap shall not be operated
below 0 °C (32 °F) to avoid condensation of C3 or C4
hydrocarbons.
6.2 Sample Recovery. The following items are needed for sample
recovery:
6.3.4 Volumetric Pipettes. One 25-ml; two each 50- and
100-ml.
6.3.5 Volumetric Flasks. One 1000-ml; two 500-ml.
6.3.6 Graduated Cylinders. One each 10- and 100-ml.
7.0 Reagents and Standards Note:
Unless otherwise indicated, it is intended that all reagents
conform to the specifications established by the Committee on
Analytical Reagents of the American Chemical Society, where such
specifications are available. Otherwise, use the best available
grade.
7.1 Sample Collection. The following reagents are required for
sample collection:
7.1.1 CdSO4 Absorbing Solution. Dissolve 41 g of 3CdSO48H2O and
15 ml of 0.1 M sulfuric acid in a 1-liter volumetric flask that
contains approximately 3/4 liter of water. Dilute to volume with
deionized, distilled water. Mix thoroughly. The pH should be 3
±0.1. Add 10 drops of Dow-Corning Antifoam B. Shake well before
use. This solution is stable for at least one month. If Antifoam B
is not used, a more labor-intensive sample recovery procedure is
required (see section 11.2).
7.1.2 Hydrogen Peroxide, 3 Percent. Dilute 30 percent H2O2 to 3
percent as needed. Prepare fresh daily.
7.1.3 Water. Deionized distilled to conform to ASTM D 1193-77 or
91, Type 3 (incorporated by reference - see § 60.17). The KMnO4
test for oxidizable organic matter may be omitted when high
concentrations of organic matter are not expected to be
present.
7.2 Sample Recovery. The following reagents are needed for
sample recovery:
7.2.1 Water. Same as section 7.1.3.
7.2.2 Hydrochloric Acid (HCl) Solution, 3 M. Add 240 ml of
concentrated HCl (specific gravity 1.19) to 500 ml of water in a
1-liter volumetric flask. Dilute to 1 liter with water. Mix
thoroughly.
7.2.3 Iodine (I2) Solution, 0.1 N. Dissolve 24 g of potassium
iodide (KI) in 30 ml of water. Add 12.7 g of resublimed iodine (I2)
to the KI solution. Shake the mixture until the I2 is completely
dissolved. If possible, let the solution stand overnight in the
dark. Slowly dilute the solution to 1 liter with water, with
swirling. Filter the solution if it is cloudy. Store solution in a
brown-glass reagent bottle.
7.2.4 Standard I2 Solution, 0.01 N. Pipette 100.0 ml of the 0.1
N iodine solution into a 1-liter volumetric flask, and dilute to
volume with water. Standardize daily as in section 10.2.1. This
solution must be protected from light. Reagent bottles and flasks
must be kept tightly stoppered.
7.3 Sample Analysis. The following reagents and standards are
needed for sample analysis:
7.3.1 Water. Same as in section 7.1.3.
7.3.2 Standard Sodium Thiosulfate Solution, 0.1 N. Dissolve 24.8
g of sodium thiosulfate pentahydrate (Na2S2O3·5H2O) or 15.8 g of
anhydrous sodium thiosulfate (Na2S2O3) in 1 liter of water, and add
0.01 g of anhydrous sodium carbonate (Na2CO3) and 0.4 ml of
chloroform (CHCl3) to stabilize. Mix thoroughly by shaking or by
aerating with nitrogen for approximately 15 minutes, and store in a
glass-stoppered, reagent bottle. Standardize as in section
10.2.2.
7.3.3 Standard Sodium Thiosulfate Solution, 0.01 N. Pipette 50.0
ml of the standard 0.1 N Na2S2O3 solution into a volumetric flask,
and dilute to 500 ml with water.
Note:
A 0.01 N phenylarsine oxide (C6H5AsO) solution may be prepared
instead of 0.01 N Na2S2O3 (see section 7.3.4).
7.3.4 Standard Phenylarsine Oxide Solution, 0.01 N. Dissolve
1.80 g of (C6H5AsO) in 150 ml of 0.3 N sodium hydroxide. After
settling, decant 140 ml of this solution into 800 ml of water.
Bring the solution to pH 6-7 with 6 N HCl, and dilute to 1 liter
with water. Standardize as in section 10.2.3.
7.3.5 Starch Indicator Solution. Suspend 10 g of soluble starch
in 100 ml of water, and add 15 g of potassium hydroxide (KOH)
pellets. Stir until dissolved, dilute with 900 ml of water, and let
stand for 1 hour. Neutralize the alkali with concentrated HCl,
using an indicator paper similar to Alkacid test ribbon, then add 2
ml of glacial acetic acid as a preservative.
Note:
Test starch indicator solution for decomposition by titrating
with 0.01 N I2 solution, 4 ml of starch solution in 200 ml of water
that contains 1 g of KI. If more than 4 drops of the 0.01 N I2
solution are required to obtain the blue color, a fresh solution
must be prepared.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Sampling Train Preparation. Assemble the sampling train as
shown in Figure 11-1, connecting the five midget impingers in
series. Place 15 ml of 3 percent H2O2 solution in the first
impinger. Leave the second impinger empty. Place 15 ml of the CdSO4
solution in the third, fourth, and fifth impingers. Place the
impinger assembly in an ice water bath container, and place water
and crushed ice around the impingers. Add more ice during the run,
if needed.
8.2 Leak-Check Procedure.
8.2.1 Connect the rubber bulb and manometer to the first
impinger, as shown in Figure 11-1. Close the petcock on the DGM
outlet. Pressurize the train to 25 cm water with the bulb, and
close off the tubing connected to the rubber bulb. The train must
hold 25 cm water pressure with not more than a 1 cm drop in
pressure in a 1-minute interval. Stopcock grease is acceptable for
sealing ground glass joints.
8.2.2 If the pump is used for sampling, it is recommended, but
not required, that the pump be leak-checked separately, either
prior to or after the sampling run. To leak-check the pump, proceed
as follows: Disconnect the drying tube from the impinger assembly.
Place a vacuum gauge at the inlet to either the drying tube or the
pump, pull a vacuum of 250 mm Hg (10 in. Hg), plug or pinch off the
outlet of the flow meter, and then turn off the pump. The vacuum
should remain stable for at least 30 seconds. If performed prior to
the sampling run, the pump leak-check should precede the leak-check
of the sampling train described immediately above; if performed
after the sampling run, the pump leak-check should follow the
sampling train leak-check.
8.3 Purge the connecting line between the sampling valve and the
first impinger by disconnecting the line from the first impinger,
opening the sampling valve, and allowing process gas to flow
through the line for one to two minutes. Then, close the sampling
valve, and reconnect the line to the impinger train. Open the
petcock on the dry gas meter outlet. Record the initial DGM
reading.
8.4 Open the sampling valve, and then adjust the valve to obtain
a rate of approximately 1 liter/min (0.035 cfm). Maintain a
constant (±10 percent) flow rate during the test. Record the DGM
temperature.
8.5 Sample for at least 10 minutes. At the end of the sampling
time, close the sampling valve, and record the final volume and
temperature readings. Conduct a leak-check as described in Section
8.2. A yellow color in the final cadmium sulfate impinger indicates
depletion of the absorbing solution. An additional cadmium sulfate
impinger should be added for subsequent samples and the sample with
yellow color in the final impinger should be voided.
8.6 Disconnect the impinger train from the sampling line.
Connect the charcoal tube and the pump as shown in Figure 11-1.
Purge the train [at a rate of 1 liter/min (0.035 ft 3/min)] with
clean ambient air for 15 minutes to ensure that all H2S is removed
from the H2O2. For sample recovery, cap the open ends, and remove
the impinger train to a clean area that is away from sources of
heat. The area should be well lighted, but not exposed to direct
sunlight.
8.7 Sample Recovery.
8.7.1 Discard the contents of the H2O2 impinger. Carefully rinse
with water the contents of the third, fourth, and fifth impingers
into a 500-ml iodine flask.
Note:
The impingers normally have only a thin film of CdS remaining
after a water rinse. If Antifoam B was not used or if significant
quantities of yellow CdS remain in the impingers, the alternative
recovery procedure in section 11.2 must be used.
8.7.2 Proceed to section 11 for the analysis.
9.0 Quality Control
Section
Quality control measure
Effect
8.2, 10.1
Sampling equipment leak-check
and calibration
Ensure accurate measurement of
sample volume.
11.2
Replicate titrations of
blanks
Ensure precision of titration
determinations.
10.0 Calibration and Standardization Note:
Maintain a log of all calibrations.
10.1 Calibration. Calibrate the sample collection equipment as
follows.
10.1.1 Dry Gas Meter.
10.1.1.1 Initial Calibration. The DGM shall be calibrated before
its initial use in the field. Proceed as follows: First, assemble
the following components in series: Drying tube, needle valve,
pump, rotameter, and DGM. Then, leak-check the metering system as
follows: Place a vacuum gauge (at least 760 mm Hg) at the inlet to
the drying tube, and pull a vacuum of 250 mm Hg (10 in. Hg); plug
or pinch off the outlet of the flow meter, and then turn off the
pump. The vacuum shall remain stable for at least 30 seconds.
Carefully release the vacuum gauge before releasing the flow meter
end. Next, calibrate the DGM (at the sampling flow rate specified
by the method) as follows: Connect an appropriately sized wet-test
meter (e.g., 1 liter per revolution) to the inlet of the
drying tube. Make three independent calibration runs, using at
least five revolutions of the DGM per run. Calculate the
calibration factor, Y (wet-test meter calibration volume divided by
the DGM volume, both volumes adjusted to the same reference
temperature and pressure), for each run, and average the results.
If any Y value deviates by more than 2 percent from the average,
the DGM is unacceptable for use. Otherwise, use the average as the
calibration factor for subsequent test runs.
10.1.1.2 Post-Test Calibration Check. After each field test
series, conduct a calibration check as in section 10.1.1.1, above,
except for the following two variations: (a) three or more
revolutions of the DGM may be used and (b) only two independent
runs need be made. If the calibration factor does not deviate by
more than 5 percent from the initial calibration factor (determined
in section 10.1.1.1), then the DGM volumes obtained during the test
series are acceptable. If the calibration factor deviates by more
than 5 percent, recalibrate the DGM as in section 10.1.1.1, and for
the calculations, use the calibration factor (initial or
recalibration) that yields the lower gas volume for each test
run.
10.1.2 Temperature Sensors. Calibrate against mercury-in-glass
thermometers. An alternative mercury-free thermometer may be used
if the thermometer is at a minimum equivalent in terms of
performance or suitably effective for the specific temperature
measurement application.
10.1.3 Rate Meter. The rate meter need not be calibrated, but
should be cleaned and maintained according to the manufacturer's
instructions.
10.1.4 Barometer. Calibrate against a mercury barometer.
10.2 Standardization.
10.2.1 Iodine Solution Standardization. Standardize the 0.01 N
I2 solution daily as follows: Pipette 25 ml of the I2 solution into
a 125-ml Erlenmeyer flask. Add 2 ml of 3 M HCl. Titrate rapidly
with standard 0.01 N Na2S2O3 solution or with 0.01 N C6H5AsO until
the solution is light yellow, using gentle mixing. Add four drops
of starch indicator solution, and continue titrating slowly until
the blue color just disappears. Record the volume of Na2S2O3
solution used, VSI, or the volume of C6H5AsO solution used, VAI, in
ml. Repeat until replicate values agree within 0.05 ml. Average the
replicate titration values which agree within 0.05 ml, and
calculate the exact normality of the I2 solution using Equation
11-3. Repeat the standardization daily.
10.2.2 Sodium Thiosulfate Solution Standardization. Standardize
the 0.1 N Na2S2O3 solution as follows: Oven-dry potassium
dichromate (K2Cr2O7) at 180 to 200 °C (360 to 390 °F). To the
nearest milligram, weigh 2 g of the dichromate (W). Transfer the
dichromate to a 500-ml volumetric flask, dissolve in water, and
dilute to exactly 500 ml. In a 500-ml iodine flask, dissolve
approximately 3 g of KI in 45 ml of water, then add 10 ml of 3 M
HCl solution. Pipette 50 ml of the dichromate solution into this
mixture. Gently swirl the contents of the flask once, and allow it
to stand in the dark for 5 minutes. Dilute the solution with 100 to
200 ml of water, washing down the sides of the flask with part of
the water. Titrate with 0.1 N Na2S2O3 until the solution is light
yellow. Add 4 ml of starch indicator and continue titrating slowly
to a green end point. Record the volume of Na2S2O3 solution used,
VS, in ml. Repeat until replicate values agree within 0.05 ml.
Calculate the normality using Equation 11-1. Repeat the
standardization each week or after each test series, whichever time
is shorter.
10.2.3 Phenylarsine Oxide Solution Standardization. Standardize
the 0.01 N C6H5AsO (if applicable) as follows: Oven-dry K2Cr2O7 at
180 to 200 °C (360 to 390 °F). To the nearest milligram, weigh 2 g
of the dichromate (W). Transfer the dichromate to a 500-ml
volumetric flask, dissolve in water, and dilute to exactly 500 ml.
In a 500-ml iodine flask, dissolve approximately 0.3 g of KI in 45
ml of water, then add 10 ml of 3 M HCl. Pipette 5 ml of the
dichromate solution into the iodine flask. Gently swirl the
contents of the flask once, and allow it to stand in the dark for 5
minutes. Dilute the solution with 100 to 200 ml of water, washing
down the sides of the flask with part of the water. Titrate with
0.01 N C6H5AsO until the solution is light yellow. Add 4 ml of
starch indicator, and continue titrating slowly to a green end
point. Record the volume of C6H5AsO used, VA, in ml. Repeat until
replicate analyses agree within 0.05 ml. Calculate the normality
using Equation 11-2. Repeat the standardization each week or after
each test series, whichever time is shorter.
11.0 Analytical Procedure
Conduct the titration analyses in a clean area away from direct
sunlight.
11.1 Pipette exactly 50 ml of 0.01 N I2 solution into a 125-ml
Erlenmeyer flask. Add 10 ml of 3 M HCl to the solution.
Quantitatively rinse the acidified I2 into the iodine flask.
Stopper the flask immediately, and shake briefly.
11.2 Use these alternative procedures if Antifoam B was not used
or if significant quantities of yellow CdS remain in the impingers.
Extract the remaining CdS from the third, fourth, and fifth
impingers using the acidified I2 solution. Immediately after
pouring the acidified I2 into an impinger, stopper it and shake for
a few moments, then transfer the liquid to the iodine flask. Do not
transfer any rinse portion from one impinger to another; transfer
it directly to the iodine flask. Once the acidified I2 solution has
been poured into any glassware containing CdS, the container must
be tightly stoppered at all times except when adding more solution,
and this must be done as quickly and carefully as possible. After
adding any acidified I2 solution to the iodine flask, allow a few
minutes for absorption of the H2S before adding any further rinses.
Repeat the I2 extraction until all CdS is removed from the
impingers. Extract that part of the connecting glassware that
contains visible CdS. Quantitatively rinse all the I2 from the
impingers, connectors, and the beaker into the iodine flask using
water. Stopper the flask and shake briefly.
11.3 Allow the iodine flask to stand about 30 minutes in the
dark for absorption of the H2S into the I2, then complete the
titration analysis as outlined in sections 11.5 and 11.6.
Note:
Iodine evaporates from acidified I2 solutions. Samples to which
acidified I2 has been added may not be stored, but must be analyzed
in the time schedule stated above.
11.4 Prepare a blank by adding 45 ml of CdSO4 absorbing solution
to an iodine flask. Pipette exactly 50 ml of 0.01 N I2 solution
into a 125-ml Erlenmeyer flask. Add 10 ml of 3 M HCl. Stopper the
flask, shake briefly, let stand 30 minutes in the dark, and titrate
with the samples.
Note:
The blank must be handled by exactly the same procedure as that
used for the samples.
11.5 Using 0.01 N Na2S2O3 solution (or 0.01 N C6H5AsO, if
applicable), rapidly titrate each sample in an iodine flask using
gentle mixing, until solution is light yellow. Add 4 ml of starch
indicator solution, and continue titrating slowly until the blue
color just disappears. Record the volume of Na2S2O3 solution used,
VTT, or the volume of C6H5AsO solution used, VAT, in ml.
11.6 Titrate the blanks in the same manner as the samples. Run
blanks each day until replicate values agree within 0.05 ml.
Average the replicate titration values which agree within 0.05
ml.
12.0 Data Analysis and Calculations
Carry out calculations, retaining at least one extra significant
figure beyond that of the acquired data. Round off figures only
after the final calculation.
12.1 Nomenclature.
CH2S = Concentration of H2S at standard conditions, mg/dscm. NA =
Normality of standard C6H5AsO solution, g-eq/liter. NI = Normality
of standard I2 solution, g-eq/liter. NS = Normality of standard
(≃0.1 N) Na2S2O3 solution, g-eq/liter. NT = Normality of standard
(≃0.01 N) Na2S2O3 solution, assumed to be 0.1 NS, g-eq/liter. Pbar
= Barometric pressure at the sampling site, mm Hg. Pstd = Standard
absolute pressure, 760 mm Hg. Tm = Average DGM temperature, °K.
Tstd = Standard absolute temperature, 293 °K. VA = Volume of
C6H5AsO solution used for standardization, ml. VAI = Volume of
standard C6H5AsO solution used for titration analysis, ml. VI =
Volume of standard I2 solution used for standardization, ml. VIT =
Volume of standard I2 solution used for titration analysis,
normally 50 ml. Vm = Volume of gas sample at meter conditions,
liters. Vm(std) = Volume of gas sample at standard conditions,
liters. VSI = Volume of “0.1 N Na2S2O3 solution used for
standardization, ml. VT = Volume of standard (≃0.01 N) Na2S2O3
solution used in standardizing iodine solution (see section
10.2.1), ml. VTT = Volume of standard (∼0.01 N) Na2S2O3 solution
used for titration analysis, ml. W = Weight of K2Cr2O7 used to
standardize Na2s2O3 or C6H5AsO solutions, as applicable (see
sections 10.2.2 and 10.2.3), g. Y = DGM calibration factor.
12.2 Normality of the Standard (≃0.1 N) Sodium Thiosulfate
Solution.
Where: 2.039 = Conversion factor = (6 g-eq
I2/mole K2Cr2O7) (1,000 ml/liter)/(294.2 g K2Cr2O7/mole) (10
aliquot factor)
12.3 Normality of Standard Phenylarsine Oxide Solution (if
applicable).
Where: 0.2039 = Conversion factor. = (6 g-eq
I2/mole K2Cr2O7) (1,000 ml/liter)/(294.2 g K2Cr2O7/mole) (100
aliquot factor)
12.4 Normality of Standard Iodine Solution.
Note:
If C6H5AsO is used instead of Na2S2O3, replace NT and VT in
Equation 11-3 with NA and VAS, respectively (see sections 10.2.1
and 10.2.3).
12.5 Dry Gas Volume. Correct the sample volume measured by the
DGM to standard conditions (20 °C and 760 mm Hg).
12.6 Concentration of H2S. Calculate the concentration of H2S in
the gas stream at standard conditions using Equation 11-5:
If C6H5AsO is used instead of NaS22O3, replace NA and VAT in
Equation 11-5 with NA and VAT, respectively (see sections 11.5 and
10.2.3).
13.0 Method Performance
13.1 Precision. Collaborative testing has shown the
intra-laboratory precision to be 2.2 percent and the
inter-laboratory precision to be 5 percent.
13.2 Bias. The method bias was shown to be −4.8 percent when
only H2S was present. In the presence of the interferences cited in
section 4.0, the bias was positive at low H2S concentration and
negative at higher concentrations. At 230 mg H2S/m 3, the level of
the compliance standard, the bias was + 2.7 percent. Thiols had no
effect on the precision.
1. Determination of Hydrogen Sulfide, Ammoniacal Cadmium
Chloride Method. API Method 772-54. In: Manual on Disposal of
Refinery Wastes, Vol. V: Sampling and Analysis of Waste Gases and
Particulate Matter. American Petroleum Institute, Washington, D.C.
1954.
2. Tentative Method of Determination of Hydrogen Sulfide and
Mercaptan Sulfur in Natural Gas. Natural Gas Processors
Association, Tulsa, OK. NGPA Publication No. 2265-65. 1965.
3. Knoll, J.D., and M.R. Midgett. Determination of Hydrogen
Sulfide in Refinery Fuel Gases. Environmental Monitoring Series,
Office of Research and Development, USEPA. Research Triangle Park,
NC 27711. EPA 600/4-77-007.
4. Scheil, G.W., and M.C. Sharp. Standardization of Method 11 at
a Petroleum Refinery. Midwest Research Institute Draft Report for
USEPA. Office of Research and Development. Research Triangle Park,
NC 27711. EPA Contract No. 68-02-1098. August 1976. EPA
600/4-77-088a (Volume 1) and EPA 600/4-77-088b (Volume 2).
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 12 -
Determination of Inorganic Lead Emissions From Stationary Sources
Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, and Method
5.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Inorganic Lead
Compounds as lead (Pb)
7439-92-1
see section 13.3.
1.2 Applicability. This method is applicable for the
determination of inorganic lead emissions from stationary sources,
only as specified in an applicable subpart of the regulations.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 Particulate and gaseous Pb emissions are withdrawn
isokinetically from the source and are collected on a filter and in
dilute nitric acid. The collected samples are digested in acid
solution and are analyzed by atomic absorption spectrophotometry
using an air/acetylene flame.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Copper. High concentrations of copper may interfere with the
analysis of Pb at 217.0 nm. This interference can be avoided by
analyzing the samples at 283.3 nm.
4.2 Matrix Effects. Analysis for Pb by flame atomic absorption
spectrophotometry is sensitive to the chemical composition and to
the physical properties (e.g., viscosity, pH) of the sample.
The analytical procedure requires the use of the Method of Standard
Additions to check for these matrix effects, and requires sample
analysis using the Method of Standard Additions if significant
matrix effects are found to be present.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Corrosive Reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water at least 15 minutes. Remove clothing
under shower and decontaminate. Treat residual chemical burn as
thermal burn.
5.2.1 Hydrogen Peroxide (H2O2). Irritating to eyes, skin, nose,
and lungs.
5.2.2 Nitric Acid (HNO3). Highly corrosive to eyes, skin, nose,
and lungs. Vapors cause bronchitis, pneumonia, or edema of lungs.
Reaction to inhalation may be delayed as long as 30 hours and still
be fatal. Provide ventilation to limit exposure. Strong oxidizer.
Hazardous reaction may occur with organic materials such as
solvents.
6.0 Equipment and Supplies
6.1 Sample Collection. A schematic of the sampling train used in
performing this method is shown in Figure 12-1 in section 18.0; it
is similar to the Method 5 train. The following items are needed
for sample collection:
6.1.1 Probe Nozzle, Probe Liner, Pitot Tube, Differential
Pressure Gauge, Filter Holder, Filter Heating System, Temperature
Sensor, Metering System, Barometer, and Gas Density Determination
Equipment. Same as Method 5, sections 6.1.1.1 through 6.1.1.7,
6.1.1.9, 6.1.2, and 6.1.3, respectively.
6.1.2 Impingers. Four impingers connected in series with
leak-free ground glass fittings or any similar leak-free
noncontaminating fittings are needed. For the first, third, and
fourth impingers, use the Greenburg-Smith design, modified by
replacing the tip with a 1.3 cm ( 1/2 in.) ID glass tube extending
to about 1.3 cm ( 1/2 in.) from the bottom of the flask. For the
second impinger, use the Greenburg-Smith design with the standard
tip.
6.1.3 Temperature Sensor. Place a temperature sensor, capable of
measuring temperature to within 1 °C (2 °F) at the outlet of the
fourth impinger for monitoring purposes.
6.2 Sample Recovery. The following items are needed for sample
recovery:
6.2.1 Probe-Liner and Probe-Nozzle Brushes, Petri Dishes,
Graduated Cylinder and/or Balance, Plastic Storage Containers, and
Funnel and Rubber Policeman. Same as Method 5, sections 6.2.1 and
6.2.4 through 6.2.7, respectively.
6.2.2 Wash Bottles. Glass (2).
6.2.3 Sample Storage Containers. Chemically resistant,
borosilicate glass bottles, for 0.1 N nitric acid (HNO3) impinger
and probe solutions and washes, 1000-ml. Use screw-cap liners that
are either rubber-backed Teflon or leak-free and resistant to
chemical attack by 0.1 N HNO3. (Narrow mouth glass bottles have
been found to be less prone to leakage.)
6.2.4 Funnel. Glass, to aid in sample recovery.
6.3 Sample Analysis. The following items are needed for sample
analysis:
6.3.1 Atomic Absorption Spectrophotometer. With lead hollow
cathode lamp and burner for air/acetylene flame.
6.3.2 Hot Plate.
6.3.3 Erlenmeyer Flasks. 125-ml, 24/40 standard taper.
6.3.4 Membrane Filters. Millipore SCWPO 4700, or equivalent.
6.3.5 Filtration Apparatus. Millipore vacuum filtration unit, or
equivalent, for use with the above membrane filter.
6.3.6 Volumetric Flasks. 100-ml, 250-ml, and 1000-ml.
7.0 Reagents and Standards Note:
Unless otherwise indicated, it is intended that all reagents
conform to the specifications established by the Committee on
Analytical Reagents of the American Chemical Society, where such
specifications are available; otherwise, use the best available
grade.
7.1 Sample Collection. The following reagents are needed for
sample collection:
7.1.1 Filter. Gelman Spectro Grade, Reeve Angel 934 AH, MSA 1106
BH, all with lot assay for Pb, or other high-purity glass fiber
filters, without organic binder, exhibiting at least 99.95 percent
efficiency (<0.05 percent penetration) on 0.3 micron dioctyl
phthalate smoke particles. Conduct the filter efficiency test using
ASTM D 2986-71, 78, or 95a (incorporated by reference - see §
60.17) or use test data from the supplier's quality control
program.
7.1.2 Silica Gel and Crushed Ice. Same as Method 5, sections
7.1.2 and 7.1.4, respectively.
7.1.3 Water. Deionized distilled, to conform to ASTM D 1193-77
or 91, Type 3 (incorporated by reference - see § 60.17). If high
concentrations of organic matter are not expected to be present,
the potassium permanganate test for oxidizable organic matter may
be omitted.
7.1.4 Nitric Acid, 0.1 N. Dilute 6.5 ml of concentrated HNO3 to
1 liter with water. (It may be desirable to run blanks before field
use to eliminate a high blank on test samples.)
7.2 Sample Recovery. 0.1 N HNO3 (Same as in section 7.1.4
above).
7.3 Sample Analysis. The following reagents and standards are
needed for sample analysis:
7.3.1 Water. Same as in section 7.1.3.
7.3.2 Nitric Acid, Concentrated.
7.3.3 Nitric Acid, 50 Percent (v/v). Dilute 500 ml of
concentrated HNO3 to 1 liter with water.
7.3.4 Stock Lead Standard Solution, 1000 µg Pb/ml. Dissolve
0.1598 g of lead nitrate [Pb(NO3)2] in about 60 ml water, add 2 ml
concentrated HNO3, and dilute to 100 ml with water.
7.3.5 Working Lead Standards. Pipet 0.0, 1.0, 2.0, 3.0, 4.0, and
5.0 ml of the stock lead standard solution (Section 7.3.4) into
250-ml volumetric flasks. Add 5 ml of concentrated HNO3 to each
flask, and dilute to volume with water. These working standards
contain 0.0, 4.0, 8.0, 12.0, 16.0, and 20.0 µg Pb/ml, respectively.
Prepare, as needed, additional standards at other concentrations in
a similar manner.
7.3.6 Air. Suitable quality for atomic absorption
spectrophotometry.
7.3.7 Acetylene. Suitable quality for atomic absorption
spectrophotometry.
7.3.8 Hydrogen Peroxide, 3 Percent (v/v). Dilute 10 ml of 30
percent H2O2 to 100 ml with water.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Pretest Preparation. Follow the same general procedure given
in Method 5, section 8.1, except that the filter need not be
weighed.
8.2 Preliminary Determinations. Follow the same general
procedure given in Method 5, section 8.2.
8.3 Preparation of Sampling Train. Follow the same general
procedure given in Method 5, section 8.3, except place 100 ml of
0.1 N HNO3 (instead of water) in each of the first two impingers.
As in Method 5, leave the third impinger empty and transfer
approximately 200 to 300 g of preweighed silica gel from its
container to the fourth impinger. Set up the train as shown in
Figure 12-1.
8.4 Leak-Check Procedures. Same as Method 5, section 8.4.
8.5 Sampling Train Operation. Same as Method 5, section 8.5.
8.6 Calculation of Percent Isokinetic. Same as Method 5, section
8.6.
8.7 Sample Recovery. Same as Method 5, sections 8.7.1 through
8.7.6.1, with the addition of the following:
8.7.1 Container No. 2 (Probe).
8.7.1.1 Taking care that dust on the outside of the probe or
other exterior surfaces does not get into the sample,
quantitatively recover sample matter and any condensate from the
probe nozzle, probe fitting, probe liner, and front half of the
filter holder by washing these components with 0.1 N HNO3 and
placing the wash into a glass sample storage container. Measure and
record (to the nearest 2 ml) the total amount of 0.1 N HNO3 used
for these rinses. Perform the 0.1 N HNO3 rinses as follows:
8.7.1.2 Carefully remove the probe nozzle, and rinse the inside
surfaces with 0.1 N HNO3 from a wash bottle while brushing with a
stainless steel, Nylon-bristle brush. Brush until the 0.1 N HNO3
rinse shows no visible particles, then make a final rinse of the
inside surface with 0.1 N HNO3.
8.7.1.3 Brush and rinse with 0.1 N HNO3 the inside parts of the
Swagelok fitting in a similar way until no visible particles
remain.
8.7.1.4 Rinse the probe liner with 0.1 N HNO3. While rotating
the probe so that all inside surfaces will be rinsed with 0.1 N
HNO3, tilt the probe, and squirt 0.1 N HNO3 into its upper end. Let
the 0.1 N HNO3 drain from the lower end into the sample container.
A glass funnel may be used to aid in transferring liquid washes to
the container. Follow the rinse with a probe brush. Hold the probe
in an inclined position, squirt 0.1 N HNO3 into the upper end of
the probe as the probe brush is being pushed with a twisting action
through the probe; hold the sample container underneath the lower
end of the probe, and catch any 0.1 N HNO3 and sample matter that
is brushed from the probe. Run the brush through the probe three
times or more until no visible sample matter is carried out with
the 0.1 N HNO3 and none remains on the probe liner on visual
inspection. With stainless steel or other metal probes, run the
brush through in the above prescribed manner at least six times,
since metal probes have small crevices in which sample matter can
be entrapped. Rinse the brush with 0.1 N HNO3, and quantitatively
collect these washings in the sample container. After the brushing,
make a final rinse of the probe as described above.
8.7.1.5 It is recommended that two people clean the probe to
minimize loss of sample. Between sampling runs, keep brushes clean
and protected from contamination.
8.7.1.6 Brush and rinse with 0.1 N HNO3 the inside of the front
half of the filter holder. Brush and rinse each surface three times
or more, if needed, to remove visible sample matter. Make a final
rinse of the brush and filter holder. After all 0.1 N HNO3 washings
and sample matter are collected in the sample container, tighten
the lid on the sample container so that the fluid will not leak out
when it is shipped to the laboratory. Mark the height of the fluid
level to determine whether leakage occurs during transport. Label
the container to identify its contents clearly.
8.7.2 Container No. 3 (Silica Gel). Note the color of the
indicating silica gel to determine if it has been completely spent,
and make a notation of its condition. Transfer the silica gel from
the fourth impinger to the original container, and seal. A funnel
may be used to pour the silica gel from the impinger and a rubber
policeman may be used to remove the silica gel from the impinger.
It is not necessary to remove the small amount of particles that
may adhere to the walls and are difficult to remove. Since the gain
in weight is to be used for moisture calculations, do not use any
water or other liquids to transfer the silica gel. If a balance is
available in the field, follow the procedure for Container No. 3 in
section 11.4.2.
8.7.3 Container No. 4 (Impingers). Due to the large quantity of
liquid involved, the impinger solutions may be placed in several
containers. Clean each of the first three impingers and connecting
glassware in the following manner:
8.7.3.1 Cap the impinger ball joints.
8.7.3.2. Rotate and agitate each impinger, so that the impinger
contents might serve as a rinse solution.
8.7.3.3 Treat the impingers as follows: Make a notation of any
color or film in the liquid catch. Measure the liquid that is in
the first three impingers by weighing it to within 0.5 g at a
minimum by using a balance. Record the weight of liquid present.
The liquid weight is needed, along with the silica gel data, to
calculate the stack gas moisture content (see Method 5, Figure
5-6).
8.7.3.4. Transfer the contents to Container No. 4.
Note:
In sections 8.7.3.5 and 8.7.3.6, measure and record the total
amount of 0.1 N HNO3 used for rinsing.
8.7.3.5. Pour approximately 30 ml of 0.1 N HNO3 into each of the
first three impingers and agitate the impingers. Drain the 0.1 N
HNO3 through the outlet arm of each impinger into Container No. 4.
Repeat this operation a second time; inspect the impingers for any
abnormal conditions.
8.7.3.6 Rinse the insides of each piece of connecting glassware
for the impingers twice with 0.1 N HNO3; transfer this rinse into
Container No. 4. Do not rinse or brush the glass-fritted filter
support. Mark the height of the fluid level to determine whether
leakage occurs during transport. Label the container to identify
its contents clearly.
8.8 Blanks.
8.8.1 Nitric Acid. Save 200 ml of the 0.1 N HNO3 used for
sampling and cleanup as a blank. Take the solution directly from
the bottle being used and place into a glass sample container
labeled “0.1 N HNO3 blank.”
8.8.2 Filter. Save two filters from each lot of filters used in
sampling. Place these filters in a container labeled “filter
blank.”
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
8.4, 10.1
Sampling equipment leak-checks
and calibration
Ensure accuracy and precision
of sampling measurements.
10.2
Spectrophotometer
calibration
Ensure linearity of
spectrophotometer response to standards.
11.5
Check for matrix effects
Eliminate matrix effects.
9.2 Volume Metering System Checks. Same as Method 5, section
9.2.
10.0 Calibration and Standardizations Note:
Maintain a laboratory log of all calibrations.
10.1 Sampling Equipment. Same as Method 5, section 10.0.
10.2 Spectrophotometer.
10.2.1 Measure the absorbance of the standard solutions using
the instrument settings recommended by the spectrophotometer
manufacturer. Repeat until good agreement (±3 percent) is obtained
between two consecutive readings. Plot the absorbance (y-axis)
versus concentration in µg Pb/ml (x-axis). Draw or compute a
straight line through the linear portion of the curve. Do not force
the calibration curve through zero, but if the curve does not pass
through the origin or at least lie closer to the origin than ±0.003
absorbance units, check for incorrectly prepared standards and for
curvature in the calibration curve.
10.2.2 To determine stability of the calibration curve, run a
blank and a standard after every five samples, and recalibrate as
necessary.
11.0 Analytical Procedures
11.1 Sample Loss Check. Prior to analysis, check the liquid
level in Containers Number 2 and Number 4. Note on the analytical
data sheet whether leakage occurred during transport. If a
noticeable amount of leakage occurred, either void the sample or
take steps, subject to the approval of the Administrator, to adjust
the final results.
11.2 Sample Preparation.
11.2.1 Container No. 1 (Filter). Cut the filter into strips and
transfer the strips and all loose particulate matter into a 125-ml
Erlenmeyer flask. Rinse the petri dish with 10 ml of 50 percent
HNO3 to ensure a quantitative transfer, and add to the flask.
Note:
If the total volume required in section 11.2.3 is expected to
exceed 80 ml, use a 250-ml flask in place of the 125-ml flask.
11.2.2 Containers No. 2 and No. 4 (Probe and Impingers). Combine
the contents of Containers No. 2 and No. 4, and evaporate to
dryness on a hot plate.
11.2.3 Sample Extraction for Lead.
11.2.3.1 Based on the approximate stack gas particulate
concentration and the total volume of stack gas sampled, estimate
the total weight of particulate sample collected. Next, transfer
the residue from Containers No. 2 and No. 4 to the 125-ml
Erlenmeyer flask that contains the sampling filter using a rubber
policeman and 10 ml of 50 percent HNO3 for every 100 mg of sample
collected in the train or a minimum of 30 ml of 50 percent HNO3,
whichever is larger.
11.2.3.2 Place the Erlenmeyer flask on a hot plate, and heat
with periodic stirring for 30 minutes at a temperature just below
boiling. If the sample volume falls below 15 ml, add more 50
percent HNO3. Add 10 ml of 3 percent H2O2, and continue heating for
10 minutes. Add 50 ml of hot (80 °C, 176 °F) water, and heat for 20
minutes. Remove the flask from the hot plate, and allow to cool.
Filter the sample through a Millipore membrane filter, or
equivalent, and transfer the filtrate to a 250-ml volumetric flask.
Dilute to volume with water.
11.2.4 Filter Blank. Cut each filter into strips, and place each
filter in a separate 125-ml Erlenmeyer flask. Add 15 ml of 50
percent HNO3, and treat as described in section 11.2.3 using 10 ml
of 3 percent H2O2 and 50 ml of hot water. Filter and dilute to a
total volume of 100 ml using water.
11.2.5 Nitric Acid Blank, 0.1 N. Take the entire 200 ml of 0.1 N
HNO3 to dryness on a steam bath, add 15 ml of 50 percent HNO3, and
treat as described in section 11.2.3 using 10 ml of 3 percent H202
and 50 ml of hot water. Dilute to a total volume of 100 ml using
water.
11.3 Spectrophotometer Preparation. Turn on the power; set the
wavelength, slit width, and lamp current; and adjust the background
corrector as instructed by the manufacturer's manual for the
particular atomic absorption spectrophotometer. Adjust the burner
and flame characteristics as necessary.
11.4 Analysis.
11.4.1 Lead Determination. Calibrate the spectrophotometer as
outlined in section 10.2, and determine the absorbance for each
source sample, the filter blank, and 0.1 N HNO3 blank. Analyze each
sample three times in this manner. Make appropriate dilutions, as
needed, to bring all sample Pb concentrations into the linear
absorbance range of the spectrophotometer. Because instruments vary
between manufacturers, no detailed operating instructions will be
given here. Instead, the instructions provided with the particular
instrument should be followed. If the Pb concentration of a sample
is at the low end of the calibration curve and high accuracy is
required, the sample can be taken to dryness on a hot plate and the
residue dissolved in the appropriate volume of water to bring it
into the optimum range of the calibration curve.
11.4.2 Container No. 3 (Silica Gel). This step may be conducted
in the field. Weigh the spent silica gel (or silica gel plus
impinger) to the nearest 0.5 g; record this weight.
11.5 Check for Matrix Effects. Use the Method of Standard
Additions as follows to check at least one sample from each source
for matrix effects on the Pb results:
11.5.1 Add or spike an equal volume of standard solution to an
aliquot of the sample solution.
11.5.2 Measure the absorbance of the resulting solution and the
absorbance of an aliquot of unspiked sample.
11.5.3 Calculate the Pb concentration Cm in µg/ml of the sample
solution using Equation 12-1 in section 12.5.
Volume corrections will not be required if the solutions as
analyzed have been made to the same final volume. Therefore, Cm and
Ca represent Pb concentration before dilutions.
Method of Standard Additions procedures described on pages 9-4
and 9-5 of the section entitled “General Information” of the Perkin
Elmer Corporation Atomic Absorption Spectrophotometry Manual,
Number 303-0152 (Reference 1 in section 17.0) may also be used. In
any event, if the results of the Method of Standard Additions
procedure used on the single source sample do not agree to within
±5 percent of the value obtained by the routine atomic absorption
analysis, then reanalyze all samples from the source using the
Method of Standard Additions procedure.
12.0 Data Analysis and Calculations
12.1 Nomenclature.
Am = Absorbance of the sample solution.
An = Cross-sectional area of nozzle, m 2 (ft 2).
At = Absorbance of the spiked sample solution.
Bws = Water in the gas stream, proportion by volume.
Ca = Lead concentration in standard solution, µg/ml.
Cm = Lead concentration in sample solution analyzed during check
for matrix effects, µg/ml.
Cs = Lead concentration in stack gas, dry basis, converted to
standard conditions, mg/dscm (gr/dscf).
I = Percent of isokinetic sampling.
L1 = Individual leakage rate observed during the leak-check
conducted prior to the first component change, m 3/min (ft
3/min).
La = Maximum acceptable leakage rate for either a pretest
leak-check or for a leak-check following a component change; equal
to 0.00057 m 3/min (0.020 cfm) or 4 percent of the average sampling
rate, whichever is less.
Li = Individual leakage rate observed during the leak-check
conducted prior to the “ith” component change (i = 1, 2, 3 * * *
n), m 3/min (cfm).
Lp = Leakage rate observed during the post-test leak-check, m
3/min (cfm).
mt = Total weight of lead collected in the sample, µg.
Mw = Molecular weight of water, 18.0 g/g-mole (18.0
lb/lb-mole).
Pbar = Barometric pressure at the sampling site, mm Hg (in.
Hg).
Ps = Absolute stack gas pressure, mm Hg (in. Hg).
Pstd = Standard absolute pressure, 760 mm Hg (29.92 in. Hg).
R = Ideal gas constant, 0.06236 [(mm Hg) (m 3)]/[(°K) (g-mole)]
{21.85 [(in. Hg) (ft 3)]/[(°R) (lb-mole)]}.
Tm = Absolute average dry gas meter temperature (see Figure 5-3
of Method 5), °K (°R).
Tstd = Standard absolute temperature, 293 °K (528 °R).
vs = Stack gas velocity, m/sec (ft/sec).
Vm = Volume of gas sample as measured by the dry gas meter, dry
basis, m 3 (ft 3).
Vm(std) = Volume of gas sample as measured by the dry gas meter,
corrected to standard conditions, m 3 (ft 3).
Vw(std) = Volume of water vapor collected in the sampling train,
corrected to standard conditions, m 3 (ft 3).
Y = Dry gas meter calibration factor.
ΔH = Average pressure differential across the orifice meter (see
Figure 5-3 of Method 5), mm H2O (in. H2O).
θ = Total sampling time, min.
θl = Sampling time interval, from the beginning of a run until
the first component change, min.
θi = Sampling time interval, between two successive component
changes, beginning with the interval between the first and second
changes, min.
θp = Sampling time interval, from the final (nth) component
change until the end of the sampling run, min.
12.2 Average Dry Gas Meter Temperatures (Tm) and Average Orifice
Pressure Drop (ΔH). See data sheet (Figure 5-3 of Method 5).
12.3 Dry Gas Volume, Volume of Water Vapor Condensed, and
Moisture Content. Using data obtained in this test, calculate
Vm(std), Vw(std), and Bws according to the procedures outlined in
Method 5, sections 12.3 through 12.5.
12.4 Total Lead in Source Sample. For each source sample,
correct the average absorbance for the contribution of the filter
blank and the 0.1 N HNO3 blank. Use the calibration curve and this
corrected absorbance to determine the Pb concentration in the
sample aspirated into the spectrophotometer. Calculate the total Pb
content mt (in µg) in the original source sample; correct for all
the dilutions that were made to bring the Pb concentration of the
sample into the linear range of the spectrophotometer.
12.5 Sample Lead Concentration. Calculate the Pb concentration
of the sample using the following equation:
12.6 Lead Concentration. Calculate the stack gas Pb
concentration Cs using Equation 12-2:
Where: K3 = 0.001 mg/µg for metric units. =
1.54 × 10−5 gr/µg for English units
12.7 Stack Gas Velocity and Volumetric Flow Rate. Calculate the
average stack gas velocity and volumetric flow rate using data
obtained in this method and the equations in sections 12.2 and 12.3
of Method 2.
12.8 Isokinetic Variation. Same as Method 5, section 12.11.
13.0 Method Performance
13.1 Precision. The within-laboratory precision, as measured by
the coefficient of variation, ranges from 0.2 to 9.5 percent
relative to a run-mean concentration. These values were based on
tests conducted at a gray iron foundry, a lead storage battery
manufacturing plant, a secondary lead smelter, and a lead recovery
furnace of an alkyl lead manufacturing plant. The concentrations
encountered during these tests ranged from 0.61 to 123.3 mg Pb/m
3.
13.2 Analytical Range. For a minimum analytical accuracy of ±10
percent, the lower limit of the range is 100 µg. The upper limit
can be extended considerably by dilution.
13.3 Analytical Sensitivity. Typical sensitivities for a
1-percent change in absorption (0.0044 absorbance units) are 0.2
and 0.5 µg Pb/ml for the 217.0 and 283.3 nm lines,
respectively.
16.1 Simultaneous Determination of Particulate Matter and Lead
Emissions. Method 12 may be used to simultaneously determine Pb and
particulate matter provided:
(1) A glass fiber filter with a low Pb background is used and
this filter is checked, desiccated and weighed per section 8.1 of
Method 5,
(2) An acetone rinse, as specified by Method 5, sections 7.2 and
8.7.6.2, is used to remove particulate matter from the probe and
inside of the filter holder prior to and kept separate from the 0.1
N HNO3 rinse of the same components,
(3) The recovered filter, the acetone rinse, and an acetone
blank (Method 5, section 7.2) are subjected to the gravimetric
analysis of Method 5, sections 6.3 and 11.0 prior to the analysis
for Pb as described below, and
(4) The entire train contents, including the 0.1 N HNO3
impingers, filter, acetone and 0.1 N HNO3 probe rinses are treated
and analyzed for Pb as described in sections 8.0 and 11.0 of this
method.
16.2 Filter Location. A filter may be used between the third and
fourth impingers provided the filter is included in the analysis
for Pb.
16.3 In-Stack Filter. An in-stack filter may be used provided:
(1) A glass-lined probe and at least two impingers, each containing
100 ml of 0.1 N HNO3 after the in-stack filter, are used and (2)
the probe and impinger contents are recovered and analyzed for Pb.
Recover sample from the nozzle with acetone if a particulate
analysis is to be made as described in section 16.1 of this
method.
16.4 Inductively Coupled Plasma-Atomic Emission Spectrometry
(ICP-AES) Analysis. ICP-AES may be used as an alternative to atomic
absorption analysis provided the following conditions are met:
16.4.1 Sample collection/recovery, sample loss check, and sample
preparation procedures are as defined in sections 8.0, 11.1, and
11.2, respectively, of this method.
16.4.2 Analysis shall be conducted following Method 6010D of
SW-846 (incorporated by reference, see § 60.17). The limit of
detection for the ICP-AES must be demonstrated according to section
15.0 of Method 301 in appendix A of part 63 of this chapter and
must be no greater than one-third of the applicable emission limit.
Perform a check for matrix effects according to section 11.5 of
this method.
16.5 Inductively Coupled Plasma-Mass Spectrometry (ICP-MS)
Analysis. ICP-MS may be used as an alternative to atomic absorption
analysis provided the following conditions are met:
16.5.1 Sample collection/recovery, sample loss check, and sample
preparation procedures are as defined in sections 8.0, 11.1, and
11.2, respectively of this method.
16.5.2 Analysis shall be conducted following Method 6020B of
SW-846 (incorporated by reference, see § 60.17). The limit of
detection for the ICP-MS must be demonstrated according to section
15.0 of Method 301 in appendix A to part 63 of this chapter and
must be no greater than one-third of the applicable emission limit.
Use the multipoint calibration curve option in section 10.4 of
Method 6020B and perform a check for matrix effects according to
section 11.5 of this method.
17.0 References
Same as Method 5, section 17.0, References 2, 3, 4, 5, and 7,
with the addition of the following:
1. Perkin Elmer Corporation. Analytical Methods for Atomic
Absorption Spectrophotometry. Norwalk, Connecticut. September
1976.
2. American Society for Testing and Materials. Annual Book of
ASTM Standards, Part 31: Water, Atmospheric Analysis. Philadelphia,
PA 1974. p. 40-42.
3. Kelin, R., and C. Hach. Standard Additions - Uses and
Limitations in Spectrophotometric Analysis. Amer. Lab.
9:21-27. 1977.
4. Mitchell, W.J., and M.R. Midgett. Determining Inorganic and
Alkyl Lead Emissions from Stationary Sources. U.S. Environmental
Protection Agency. Emission Monitoring and Support Laboratory.
Research Triangle Park, NC. (Presented at National APCA Meeting,
Houston. June 26, 1978).
18.0 Tables, Diagrams, Flowcharts, and Validation Data Method 13A -
Determination of Total Fluoride Emissions From Stationary Sources
(Spadns Zirconium Lake Method) Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, and Method
5.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Total fluorides as
Fluorine
7782-41-4
Not determined.
1.2 Applicability. This method is applicable for the
determination of fluoride (F−) emissions from sources as specified
in the regulations. It does not measure fluorocarbons, such as
Freons.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary
Gaseous and particulate F− are withdrawn isokinetically from the
source and collected in water and on a filter. The total F− is then
determined by the SPADNS Zirconium Lake Colorimetric method.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Chloride. Large quantities of chloride will interfere with
the analysis, but this interference can be prevented by adding
silver sulfate into the distillation flask (see section 11.3). If
chloride ion is present, it may be easier to use the specific ion
electrode method of analysis (Method 13B).
4.2 Grease. Grease on sample-exposed surfaces may cause low F−
results due to adsorption.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Corrosive Reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water at least 15 minutes. Remove clothing
under shower and decontaminate. Treat residual chemical burn as
thermal burn.
5.2.1 Hydrochloric Acid (HCl). Highly toxic. Vapors are highly
irritating to eyes, skin, nose, and lungs, causing severe damage.
May cause bronchitis, pneumonia, or edema of lungs. Exposure to
concentrations of 0.13 to 0.2 percent can be lethal in minutes.
Will react with metals, producing hydrogen.
5.2.2 Sodium Hydroxide (NaOH). Causes severe damage to eye
tissues and to skin. Inhalation causes irritation to nose, throat,
and lungs. Reacts exothermically with limited amounts of water.
5.2.3 Sulfuric Acid (H2SO4). Rapidly destructive to body tissue.
Will cause third degree burns. Eye damage may result in blindness.
Inhalation may be fatal from spasm of the larynx, usually within 30
minutes. May cause lung tissue damage with edema. 1 mg/m 3 for 8
hours will cause lung damage or, in higher concentrations, death.
Provide ventilation to limit inhalation. Reacts violently with
metals and organics.
6.0 Equipment and Supplies
6.1 Sample Collection. A schematic of the sampling train used in
performing this method is shown in Figure 13A-1; it is similar to
the Method 5 sampling train except that the filter position is
interchangeable. The sampling train consists of the following
components:
6.1.1 Probe Nozzle, Pitot Tube, Differential Pressure Gauge,
Filter Heating System, Temperature Sensor, Metering System,
Barometer, and Gas Density Determination Equipment. Same as Method
5, sections 6.1.1.1, 6.1.1.3 through 6.1.1.7, 6.1.1.9, 6.1.2, and
6.1.3, respectively. The filter heating system and temperature
sensor are needed only when moisture condensation is a problem.
6.1.2 Probe Liner. Borosilicate glass or 316 stainless steel.
When the filter is located immediately after the probe, a probe
heating system may be used to prevent filter plugging resulting
from moisture condensation, but the temperature in the probe shall
not be allowed to exceed 120 ±14 °C (248 ±25 °F).
6.1.3 Filter Holder. With positive seal against leakage from the
outside or around the filter. If the filter is located between the
probe and first impinger, use borosilicate glass or stainless steel
with a 20-mesh stainless steel screen filter support and a silicone
rubber gasket; do not use a glass frit or a sintered metal filter
support. If the filter is located between the third and fourth
impingers, borosilicate glass with a glass frit filter support and
a silicone rubber gasket may be used. Other materials of
construction may be used, subject to the approval of the
Administrator.
6.1.4 Impingers. Four impingers connected as shown in Figure
13A-1 with ground-glass (or equivalent), vacuum-tight fittings. For
the first, third, and fourth impingers, use the Greenburg-Smith
design, modified by replacing the tip with a 1.3-cm ( 1/2 in.) ID
glass tube extending to 1.3 cm ( 1/2 in.) from the bottom of the
flask. For the second impinger, use a Greenburg-Smith impinger with
the standard tip. Modifications (e.g., flexible connections
between the impingers or materials other than glass) may be used,
subject to the approval of the Administrator. Place a temperature
sensor, capable of measuring temperature to within 1 °C (2 °F), at
the outlet of the fourth impinger for monitoring purposes.
6.2 Sample Recovery. The following items are needed for sample
recovery:
6.2.1 Probe-liner and Probe-Nozzle Brushes, Wash Bottles,
Graduated Cylinder and/or Balance, Plastic Storage Containers,
Funnel and Rubber Policeman, and Funnel. Same as Method 5, sections
6.2.1, 6.2.2 and 6.2.5 to 6.2.8, respectively.
6.2.2 Sample Storage Container. Wide-mouth, high-density
polyethylene bottles for impinger water samples, 1 liter.
6.3 Sample Preparation and Analysis. The following items are
needed for sample preparation and analysis:
6.3.1 Distillation Apparatus. Glass distillation apparatus
assembled as shown in Figure 13A-2.
6.3.2 Bunsen Burner.
6.3.3 Electric Muffle Furnace. Capable of heating to 600 °C
(1100 °F).
6.3.4 Crucibles. Nickel, 75- to 100-ml.
6.3.5 Beakers. 500-ml and 1500-ml.
6.3.6 Volumetric Flasks. 50-ml.
6.3.7 Erlenmeyer Flasks or Plastic Bottles. 500-ml.
6.3.8 Constant Temperature Bath. Capable of maintaining a
constant temperature of ±1.0 °C at room temperature conditions.
6.3.9 Balance. 300-g capacity, to measure to ±0.5 g.
6.3.10 Spectrophotometer. Instrument that measures absorbance at
570 nm and provides at least a 1-cm light path.
6.3.11 Spectrophotometer Cells. 1-cm path length.
7.0 Reagents and Standards
Unless otherwise indicated, all reagents are to conform to the
specifications established by the Committee on Analytical Reagents
of the American Chemical Society, where such specifications are
available. Otherwise, use the best available grade.
7.1 Sample Collection. The following reagents are needed for
sample collection:
7.1.1 Filters.
7.1.1.1 If the filter is located between the third and fourth
impingers, use a Whatman No. 1 filter, or equivalent, sized to fit
the filter holder.
7.1.1.2 If the filter is located between the probe and first
impinger, use any suitable medium (e.g., paper, organic
membrane) that can withstand prolonged exposure to temperatures up
to 135 °C (275 °F), and has at least 95 percent collection
efficiency (<5 percent penetration) for 0.3 µm dioctyl phthalate
smoke particles. Conduct the filter efficiency test before the test
series, using ASTM D 2986-71, 78, or 95a (incorporated by reference
- see § 60.17), or use test data from the supplier's quality
control program. The filter must also have a low F− blank value
(<0.015 mg F−/cm 2 of filter area). Before the test series,
determine the average F− blank value of at least three filters
(from the lot to be used for sampling) using the applicable
procedures described in sections 8.3 and 8.4 of this method. In
general, glass fiber filters have high and/or variable F− blank
values, and will not be acceptable for use.
7.1.2 Water. Deionized distilled, to conform to ASTM D 1193-77
or 91, Type 3 (incorporated by reference - see § 60.17). If high
concentrations of organic matter are not expected to be present,
the potassium permanganate test for oxidizable organic matter may
be deleted.
7.1.3 Silica Gel, Crushed Ice, and Stopcock Grease. Same as
Method 5, sections 7.1.2, 7.1.4, and 7.1.5, respectively.
7.2 Sample Recovery. Water, as described in section 7.1.2, is
needed for sample recovery.
7.3 Sample Preparation and Analysis. The following reagents and
standards are needed for sample preparation and analysis:
7.3.2 Phenolphthalein Indicator. Dissolve 0.1 g of
phenolphthalein in a mixture of 50 ml of 90 percent ethanol and 50
ml of water.
7.3.3 Silver Sulfate (Ag2SO4).
7.3.4 Sodium Hydroxide (NaOH), Pellets.
7.3.5 Sulfuric Acid (H2SO4), Concentrated.
7.3.6 Sulfuric Acid, 25 Percent (v/v). Mix 1 part of
concentrated H2SO4 with 3 parts of water.
7.3.7 Filters. Whatman No. 541, or equivalent.
7.3.8 Hydrochloric Acid (HCl), Concentrated.
7.3.9 Water. Same as in section 7.1.2.
7.3.10 Fluoride Standard Solution, 0.01 mg F−/ml. Dry
approximately 0.5 g of sodium fluoride (NaF) in an oven at 110 °C
(230 °F) for at least 2 hours. Dissolve 0.2210 g of NaF in 1 liter
of water. Dilute 100 ml of this solution to 1 liter with water.
7.3.11 SPADNS Solution [4,5
Dihydroxyl-3-(p-Sulfophenylazo)-2,7-Naphthalene-Disulfonic Acid
Trisodium Salt]. Dissolve 0.960 ±0.010 g of SPADNS reagent in 500
ml water. If stored in a well-sealed bottle protected from the
sunlight, this solution is stable for at least 1 month.
7.3.12 Spectrophotometer Zero Reference Solution. Add 10 ml of
SPADNS solution to 100 ml water, and acidify with a solution
prepared by diluting 7 ml of concentrated HCl to 10 ml with
deionized, distilled water. Prepare daily.
7.3.13 SPADNS Mixed Reagent. Dissolve 0.135 ±0.005 g of zirconyl
chloride octahydrate (ZrOCl2 8H2O) in 25 ml of water. Add 350 ml of
concentrated HCl, and dilute to 500 ml with deionized, distilled
water. Mix equal volumes of this solution and SPADNS solution to
form a single reagent. This reagent is stable for at least 2
months.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Pretest Preparation. Follow the general procedure given in
Method 5, section 8.1, except that the filter need not be
weighed.
8.2 Preliminary Determinations. Follow the general procedure
given in Method 5, section 8.2, except that the nozzle size must be
selected such that isokinetic sampling rates below 28 liters/min
(1.0 cfm) can be maintained.
8.3 Preparation of Sampling Train. Follow the general procedure
given in Method 5, section 8.3, except for the following variation:
Assemble the train as shown in Figure 13A-1 with the filter between
the third and fourth impingers. Alternatively, if a 20-mesh
stainless steel screen is used for the filter support, the filter
may be placed between the probe and first impinger. A filter
heating system to prevent moisture condensation may be used, but
shall not allow the temperature to exceed 120 ±14 °C (248 ±25 °F).
Record the filter location on the data sheet (see section 8.5).
8.4 Leak-Check Procedures. Follow the leak-check procedures
given in Method 5, section 8.4.
8.5 Sampling Train Operation. Follow the general procedure given
in Method 5, section 8.5, keeping the filter and probe temperatures
(if applicable) at 120 ±14 °C (248 ±25 °F) and isokinetic sampling
rates below 28 liters/min (1.0 cfm). For each run, record the data
required on a data sheet such as the one shown in Method 5, Figure
5-3.
8.6 Sample Recovery. Proper cleanup procedure begins as soon as
the probe is removed from the stack at the end of the sampling
period. Allow the probe to cool.
8.6.1 When the probe can be safely handled, wipe off all
external particulate matter near the tip of the probe nozzle, and
place a cap over it to keep from losing part of the sample. Do not
cap off the probe tip tightly while the sampling train is cooling
down as this would create a vacuum in the filter holder, thus
drawing water from the impingers into the filter holder.
8.6.2 Before moving the sample train to the cleanup site, remove
the probe from the sample train, wipe off any silicone grease, and
cap the open outlet of the probe. Be careful not to lose any
condensate that might be present. Remove the filter assembly, wipe
off any silicone grease from the filter holder inlet, and cap this
inlet. Remove the umbilical cord from the last impinger, and cap
the impinger. After wiping off any silicone grease, cap off the
filter holder outlet and any open impinger inlets and outlets.
Ground-glass stoppers, plastic caps, or serum caps may be used to
close these openings.
8.6.3 Transfer the probe and filter-impinger assembly to the
cleanup area. This area should be clean and protected from the wind
so that the chances of contaminating or losing the sample will be
minimized.
8.6.4 Inspect the train prior to and during disassembly, and
note any abnormal conditions. Treat the samples as follows:
8.6.4.1 Container No. 1 (Probe, Filter, and Impinger
Catches).
8.6.4.1.1 Using a graduated cylinder, measure to the nearest ml,
and record the volume of the water in the first three impingers;
include any condensate in the probe in this determination. Transfer
the impinger water from the graduated cylinder into a polyethylene
container. Add the filter to this container. (The filter may be
handled separately using procedures subject to the Administrator's
approval.) Taking care that dust on the outside of the probe or
other exterior surfaces does not get into the sample, clean all
sample-exposed surfaces (including the probe nozzle, probe fitting,
probe liner, first three impingers, impinger connectors, and filter
holder) with water. Use less than 500 ml for the entire wash. Add
the washings to the sample container. Perform the water rinses as
follows:
8.6.4.1.2 Carefully remove the probe nozzle and rinse the inside
surface with water from a wash bottle. Brush with a Nylon bristle
brush, and rinse until the rinse shows no visible particles, after
which make a final rinse of the inside surface. Brush and rinse the
inside parts of the Swagelok fitting with water in a similar
way.
8.6.4.1.3 Rinse the probe liner with water. While squirting the
water into the upper end of the probe, tilt and rotate the probe so
that all inside surfaces will be wetted with water. Let the water
drain from the lower end into the sample container. A funnel (glass
or polyethylene) may be used to aid in transferring the liquid
washes to the container. Follow the rinse with a probe brush. Hold
the probe in an inclined position, and squirt water into the upper
end as the probe brush is being pushed with a twisting action
through the probe. Hold the sample container underneath the lower
end of the probe, and catch any water and particulate matter that
is brushed from the probe. Run the brush through the probe three
times or more. With stainless steel or other metal probes, run the
brush through in the above prescribed manner at least six times
since metal probes have small crevices in which particulate matter
can be entrapped. Rinse the brush with water, and quantitatively
collect these washings in the sample container. After the brushing,
make a final rinse of the probe as described above.
8.6.4.1.4 It is recommended that two people clean the probe to
minimize sample losses. Between sampling runs, keep brushes clean
and protected from contamination.
8.6.4.1.5 Rinse the inside surface of each of the first three
impingers (and connecting glassware) three separate times. Use a
small portion of water for each rinse, and brush each
sample-exposed surface with a Nylon bristle brush, to ensure
recovery of fine particulate matter. Make a final rinse of each
surface and of the brush.
8.6.4.1.6 After ensuring that all joints have been wiped clean
of the silicone grease, brush and rinse with water the inside of
the filter holder (front-half only, if filter is positioned between
the third and fourth impingers). Brush and rinse each surface three
times or more if needed. Make a final rinse of the brush and filter
holder.
8.6.4.1.7 After all water washings and particulate matter have
been collected in the sample container, tighten the lid so that
water will not leak out when it is shipped to the laboratory. Mark
the height of the fluid level to transport. Label the container
clearly to identify its contents.
8.6.4.2 Container No. 2 (Sample Blank). Prepare a blank by
placing an unused filter in a polyethylene container and adding a
volume of water equal to the total volume in Container No. 1.
Process the blank in the same manner as for Container No. 1.
8.6.4.3 Container No. 3 (Silica Gel). Note the color of the
indicating silica gel to determine whether it has been completely
spent, and make a notation of its condition. Transfer the silica
gel from the fourth impinger to its original container, and seal. A
funnel may be used to pour the silica gel and a rubber policeman to
remove the silica gel from the impinger. It is not necessary to
remove the small amount of dust particles that may adhere to the
impinger wall and are difficult to remove. Since the gain in weight
is to be used for moisture calculations, do not use any water or
other liquids to transfer the silica gel. If a balance is available
in the field, follow the analytical procedure for Container No. 3
in section 11.4.2.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
8.4, 10.1
Sampling equipment leak-check
and calibration
Ensure accurate measurement of
stack gas flow rate and sample volume.
10.2
Spectrophotometer
calibration
Evaluate analytical technique,
preparation of standards.
11.3.3
Interference/recovery
efficiency check during distillation
Minimize negative effects of
used acid.
9.2 Volume Metering System Checks. Same as Method 5, section
9.2.
10.0 Calibration and Standardization Note:
Maintain a laboratory log of all calibrations.
10.1 Sampling Equipment. Calibrate the probe nozzle, pitot tube,
metering system, probe heater, temperature sensors, and barometer
according to the procedures outlined in Method 5, sections 10.1
through 10.6. Conduct the leak-check of the metering system
according to the procedures outlined in Method 5, section
8.4.1.
10.2 Spectrophotometer.
10.2.1 Prepare the blank standard by adding 10 ml of SPADNS
mixed reagent to 50 ml of water.
10.2.2 Accurately prepare a series of standards from the 0.01 mg
F−/ml standard fluoride solution (Section 7.3.10) by diluting 0, 2,
4, 6, 8, 10, 12, and 14 ml to 100 ml with deionized, distilled
water. Pipet 50 ml from each solution, and transfer each to a
separate 100-ml beaker. Then add 10 ml of SPADNS mixed reagent
(Section 7.3.13) to each. These standards will contain 0, 10, 20,
30, 40, 50, 60, and 70 µg F−(0 to 1.4 µg/ml), respectively.
10.2.3 After mixing, place the blank and calibration standards
in a constant temperature bath for 30 minutes before reading the
absorbance with the spectrophotometer. Adjust all samples to this
same temperature before analyzing.
10.2.4 With the spectrophotometer at 570 nm, use the blank
standard to set the absorbance to zero. Determine the absorbance of
the standards.
10.2.5 Prepare a calibration curve by plotting µg F−/50 ml
versus absorbance on linear graph paper. Prepare the standard curve
initially and thereafter whenever the SPADNS mixed reagent is newly
made. Also, run a calibration standard with each set of samples
and, if it differs from the calibration curve by more than ±2
percent, prepare a new standard curve.
11.0 Analytical Procedures
11.1 Sample Loss Check. Note the liquid levels in Containers No.
1 and No. 2, determine whether leakage occurred during transport,
and note this finding on the analytical data sheet. If noticeable
leakage has occurred, either void the sample or use methods,
subject to the approval of the Administrator, to correct the final
results.
11.2 Sample Preparation. Treat the contents of each sample
container as described below:
11.2.1 Container No. 1 (Probe, Filter, and Impinger Catches).
Filter this container's contents, including the sampling filter,
through Whatman No. 541 filter paper, or equivalent, into a 1500-ml
beaker.
11.2.1.1 If the filtrate volume exceeds 900 ml, make the
filtrate basic (red to phenolphthalein) with NaOH, and evaporate to
less than 900 ml.
11.2.1.2 Place the filtered material (including sampling filter)
in a nickel crucible, add a few ml of water, and macerate the
filters with a glass rod.
11.2.1.2.1 Add 100 mg CaO to the crucible, and mix the contents
thoroughly to form a slurry. Add two drops of phenolphthalein
indicator. Place the crucible in a hood under infrared lamps or on
a hot plate at low heat. Evaporate the water completely. During the
evaporation of the water, keep the slurry basic (red to
phenolphthalein) to avoid loss of F−. If the indicator turns
colorless (acidic) during the evaporation, add CaO until the color
turns red again.
11.2.1.2.2 After evaporation of the water, place the crucible on
a hot plate under a hood, and slowly increase the temperature until
the Whatman No. 541 and sampling filters char. It may take several
hours to char the filters completely.
11.2.1.2.3 Place the crucible in a cold muffle furnace.
Gradually (to prevent smoking) increase the temperature to 600 °C
(1100 °F), and maintain this temperature until the contents are
reduced to an ash. Remove the crucible from the furnace, and allow
to cool.
11.2.1.2.4 Add approximately 4 g of crushed NaOH to the
crucible, and mix. Return the crucible to the muffle furnace, and
fuse the sample for 10 minutes at 600 °C.
11.2.1.2.5 Remove the sample from the furnace, and cool to
ambient temperature. Using several rinsings of warm water, transfer
the contents of the crucible to the beaker containing the filtrate.
To ensure complete sample removal, rinse finally with two 20-ml
portions of 25 percent H2SO4, and carefully add to the beaker. Mix
well, and transfer to a 1-liter volumetric flask. Dilute to volume
with water, and mix thoroughly. Allow any undissolved solids to
settle.
11.2.2 Container No. 2 (Sample Blank). Treat in the same manner
as described in section 11.2.1 above.
11.2.3 Adjustment of Acid/Water Ratio in Distillation Flask.
Place 400 ml of water in the distillation flask, and add 200 ml of
concentrated H2SO4. Add some soft glass beads and several small
pieces of broken glass tubing, and assemble the apparatus as shown
in Figure 13A-2. Heat the flask until it reaches a temperature of
175 °C (347 °F) to adjust the acid/water ratio for subsequent
distillations. Discard the distillate.
Caution: Use a protective shield when carrying out this
procedure. Observe standard precautions when mixing H2SO4 with
water. Slowly add the acid to the flask with constant swirling.
11.3 Distillation.
11.3.1 Cool the contents of the distillation flask to below 80
°C (180 °F). Pipet an aliquot of sample containing less than 10.0
mg F− directly into the distillation flask, and add water to make a
total volume of 220 ml added to the distillation flask. (To
estimate the appropriate aliquot size, select an aliquot of the
solution, and treat as described in section 11.4.1. This will be an
approximation of the F− content because of possible interfering
ions.)
Note:
If the sample contains chloride, add 5 mg of Ag2SO4 to the flask
for every mg of chloride.
11.3.2 Place a 250-ml volumetric flask at the condenser exit.
Heat the flask as rapidly as possible with a Bunsen burner, and
collect all the distillate up to 175 °C (347 °F). During heatup,
play the burner flame up and down the side of the flask to prevent
bumping. Conduct the distillation as rapidly as possible (15
minutes or less). Slow distillations have been found to produce low
F− recoveries. Be careful not to exceed 175 °C (347 °F) to avoid
causing H2SO4 to distill over. If F− distillation in the mg range
is to be followed by a distillation in the fractional mg range, add
220 ml of water and distill it over as in the acid adjustment step
to remove residual F− from the distillation system.
11.3.3 The acid in the distillation flask may be used until
there is carry-over of interferences or poor F− recovery. Check for
interference and for recovery efficiency every tenth distillation
using a water blank and a standard solution. Change the acid
whenever the F− recovery is less than 90 percent or the blank value
exceeds 0.1 µg/ml.
11.4 Sample Analysis.
11.4.1 Containers No. 1 and No. 2.
11.4.1.1 After distilling suitable aliquots from Containers No.
1 and No. 2 according to section 11.3, dilute the distillate in the
volumetric flasks to exactly 250 ml with water, and mix thoroughly.
Pipet a suitable aliquot of each sample distillate (containing 10
to 40 µg F−/ml) into a beaker, and dilute to 50 ml with water. Use
the same aliquot size for the blank. Add 10 ml of SPADNS mixed
reagent (Section 7.3.13), and mix thoroughly.
11.4.1.2 After mixing, place the sample in a
constant-temperature bath containing the standard solutions for 30
minutes before reading the absorbance on the spectrophotometer.
Note:
After the sample and colorimetric reagent are mixed, the color
formed is stable for approximately 2 hours. Also, a 3 °C (5.4 °F)
temperature difference between the sample and standard solutions
produces an error of approximately 0.005 mg F−/liter. To avoid this
error, the absorbencies of the sample and standard solutions must
be measured at the same temperature.
11.4.1.3 Set the spectrophotometer to zero absorbance at 570 nm
with the zero reference solution (Section 7.3.12), and check the
spectrophotometer calibration with the standard solution (Section
7.3.10). Determine the absorbance of the samples, and determine the
concentration from the calibration curve. If the concentration does
not fall within the range of the calibration curve, repeat the
procedure using a different size aliquot.
11.4.2 Container No. 3 (Silica Gel). Weigh the spent silica gel
(or silica gel plus impinger) to the nearest 0.5 g using a balance.
This step may be conducted in the field.
12.0 Data Analysis and Calculations
Carry out calculations, retaining at least one extra significant
figure beyond that of the acquired data. Round off figures after
final calculation. Other forms of the equations may be used,
provided that they yield equivalent results.
12.1 Nomenclature.
Ad = Aliquot of distillate taken for color development, ml. At =
Aliquot of total sample added to still, ml. Bws = Water vapor in
the gas stream, portion by volume. Cs = Concentration of F− in
stack gas, mg/dscm (gr/dscf). Fc = F− concentration from the
calibration curve, µg. Ft = Total F− in sample, mg. Tm = Absolute
average dry gas meter (DGM) temperature (see Figure 5-3 of Method
5), °K (°R). Ts = Absolute average stack gas temperature (see
Figure 5-3 of Method 5), °K (°R). Vd = Volume of distillate as
diluted, ml. Vm(std) = Volume of gas sample as measured by DGM at
standard conditions, dscm (dscf). Vt = Total volume of F− sample,
after final dilution, ml. Vw(std) = Volume of water vapor in the
gas sample at standard conditions, scm (scf)
12.2 Average DGM Temperature and Average Orifice Pressure Drop
(see Figure 5-3 of Method 5).
12.3 Dry Gas Volume. Calculate Vm(std), and adjust for leakage,
if necessary, using Equation 5-1 of Method 5.
12.4 Volume of Water Vapor and Moisture Content. Calculate
Vw(std) and Bws from the data obtained in this method. Use
Equations 5-2 and 5-3 of Method 5.
12.5 Total Fluoride in Sample. Calculate the amount of F− in the
sample using the following equation:
12.6 Fluoride Concentration in Stack Gas. Determine the F−
concentration in the stack gas using the following equation:
12.7 Isokinetic Variation. Same as Method 5, section 12.11.
13.0 Method Performance
The following estimates are based on a collaborative test done
at a primary aluminum smelter. In the test, six laboratories each
sampled the stack simultaneously using two sampling trains for a
total of 12 samples per sampling run. Fluoride concentrations
encountered during the test ranged from 0.1 to 1.4 mg F−/m 3.
13.1 Precision. The intra- and inter-laboratory standard
deviations, which include sampling and analysis errors, were 0.044
mg F−/m 3 with 60 degrees of freedom and 0.064 mg F−/m 3 with five
degrees of freedom, respectively.
13.2 Bias. The collaborative test did not find any bias in the
analytical method.
13.3 Range. The range of this method is 0 to 1.4 µg F−/ml.
16.1 Compliance with ASTM D 3270-73T, 80, 91, or 95
(incorporated by reference - see § 60.17) “Analysis of Fluoride
Content of the Atmosphere and Plant Tissues (Semiautomated Method)
is an acceptable alternative for the requirements specified in
sections 11.2, 11.3, and 11.4.1 when applied to suitable aliquots
of Containers 1 and 2 samples.
17.0 References
1. Bellack, Ervin. Simplified Fluoride Distillation Method. J.
of the American Water Works Association. 50:5306. 1958.
2. Mitchell, W.J., J.C. Suggs, and F.J. Bergman. Collaborative
Study of EPA Method 13A and Method 13B. Publication No.
EPA-300/4-77-050. U.S. Environmental Protection Agency, Research
Triangle Park, NC. December 1977.
3. Mitchell, W.J., and M.R. Midgett. Adequacy of Sampling Trains
and Analytical Procedures Used for Fluoride. Atm. Environ.
10:865-872. 1976.
18.0 Tables, Diagrams, Flowcharts, and Validation Data Method 13B -
Determination of Total Fluoride Emissions From Stationary Sources
(Specific Ion Electrode Method) Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, Method 5,
and Method 13A.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Total fluorides as
Fluorine
7782-41-4
Not determined.
1.2 Applicability. This method is applicable for the
determination of fluoride (F−) emissions from sources as specified
in the regulations. It does not measure fluorocarbons, such as
Freons.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary
Gaseous and particulate F− are withdrawn isokinetically from the
source and collected in water and on a filter. The total F− is then
determined by the specific ion electrode method.
3.0 Definitions [Reserved] 4.0 Interferences
Grease on sample-exposed surfaces may cause low F− results
because of adsorption.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method does not purport to
address all of the safety problems associated with its use. It is
the responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Corrosive Reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water at least 15 minutes. Remove clothing
under shower and decontaminate. Treat residual chemical burn as
thermal burn.
5.2.1 Sodium Hydroxide (NaOH). Causes severe damage to eye
tissues and to skin. Inhalation causes irritation to nose, throat,
and lungs. Reacts exothermically with limited amounts of water.
5.2.2 Sulfuric Acid (H2SO4). Rapidly destructive to body tissue.
Will cause third degree burns. Eye damage may result in blindness.
Inhalation may be fatal from spasm of the larynx, usually within 30
minutes. May cause lung tissue damage with edema. 1 mg/m 3 for 8
hours will cause lung damage or, in higher concentrations, death.
Provide ventilation to limit inhalation. Reacts violently with
metals and organics.
6.0 Equipment and Supplies
6.1 Sample Collection and Sample Recovery. Same as Method 13A,
sections 6.1 and 6.2, respectively.
6.2 Sample Preparation and Analysis. The following items are
required for sample preparation and analysis:
6.2.1 Distillation Apparatus, Bunsen Burner, Electric Muffle
Furnace, Crucibles, Beakers, Volumetric Flasks, Erlenmeyer Flasks
or Plastic Bottles, Constant Temperature Bath, and Balance. Same as
Method 13A, sections 6.3.1 to 6.3.9, respectively.
6.2.2 Fluoride Ion Activity Sensing Electrode.
6.2.3 Reference Electrode. Single junction, sleeve type.
6.2.4 Electrometer. A pH meter with millivolt-scale capable of
±0.1-mv resolution, or a specific ion meter made specifically for
specific ion electrode use.
6.2.5 Magnetic Stirrer and Tetrafluoroethylene (TFE)
Fluorocarbon-Coated Stirring Bars.
6.2.6 Beakers. Polyethylene, 100-ml.
7.0 Reagents and Standards
Unless otherwise indicated, all reagents are to conform to the
specifications established by the Committee on Analytical Reagents
of the American Chemical Society, where such specifications are
available. Otherwise, use the best available grade.
7.1 Sample Collection and Sample Recovery. Same as Method 13A,
sections 7.1 and 7.2, respectively.
7.2 Sample Preparation and Analysis. The following reagents and
standards are required for sample analysis:
7.2.2 Phenolphthalein Indicator. Dissolve 0.1 g phenolphthalein
in a mixture of 50 ml of 90 percent ethanol and 50 ml water.
7.2.3 Sodium Hydroxide (NaOH), Pellets.
7.2.4 Sulfuric Acid (H2SO4), Concentrated.
7.2.5 Filters. Whatman No. 541, or equivalent.
7.2.6 Water. Same as section 7.1.2 of Method 13A.
7.2.7 Sodium Hydroxide, 5 M. Dissolve 20 g of NaOH in 100 ml of
water.
7.2.8 Sulfuric Acid, 25 Percent (v/v). Mix 1 part of
concentrated H2SO4 with 3 parts of water.
7.2.9 Total Ionic Strength Adjustment Buffer (TISAB). Place
approximately 500 ml of water in a 1-liter beaker. Add 57 ml of
glacial acetic acid, 58 g of sodium chloride, and 4 g of
cyclohexylene dinitrilo tetraacetic acid. Stir to dissolve. Place
the beaker in a water bath and cool to 20 °C (68 °F). Slowly add 5
M NaOH to the solution, measuring the pH continuously with a
calibrated pH/reference electrode pair, until the pH is 5.3. Pour
into a 1-liter volumetric flask, and dilute to volume with
deionized, distilled water. Commercially prepared TISAB may be
substituted for the above.
7.2.10 Fluoride Standard Solution, 0.1 M. Oven dry approximately
10 g of sodium fluoride (NaF) for a minimum of 2 hours at 110 °C
(230 °F), and store in a desiccator. Then add 4.2 g of NaF to a
1-liter volumetric flask, and add enough water to dissolve. Dilute
to volume with water.
8.0 Sample Collection, Preservation, Storage, and Transport
Same as Method 13A, section 8.0.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
8.0, 10.1
Sampling equipment leak-check
and calibration
Ensure accurate measurement of
stack gas flow rate and sample volume.
10.2
Fluoride electrode
Evaluate analytical technique,
preparation of standards.
11.1
Interference/recovery
efficiency-check during distillation
Minimize negative effects of
used acid.
9.2 Volume Metering System Checks. Same as Method 5, section
9.2.
10.0 Calibration and Standardizations Note:
Maintain a laboratory log of all calibrations.
10.1 Sampling Equipment. Same as Method 13A, section 10.1.
10.2 Fluoride Electrode. Prepare fluoride standardizing
solutions by serial dilution of the 0.1 M fluoride standard
solution. Pipet 10 ml of 0.1 M fluoride standard solution into a
100-ml volumetric flask, and make up to the mark with water for a
10−2 M standard solution. Use 10 ml of 10−2 M solution to make a
10−3 M solution in the same manner. Repeat the dilution procedure,
and make 10−4 and 10−5 M solutions.
10.2.1 Pipet 50 ml of each standard into a separate beaker. Add
50 ml of TISAB to each beaker. Place the electrode in the most
dilute standard solution. When a steady millivolt reading is
obtained, plot the value on the linear axis of semilog graph paper
versus concentration on the log axis. Plot the nominal value for
concentration of the standard on the log axis, (e.g., when
50 ml of 10−2 M standard is diluted with 50 ml of TISAB, the
concentration is still designated “10−2 M”).
10.2.2 Between measurements, soak the fluoride sensing electrode
in water for 30 seconds, and then remove and blot dry. Analyze the
standards going from dilute to concentrated standards. A
straight-line calibration curve will be obtained, with nominal
concentrations of 10−4, 10−3, 10−2, 10−1 fluoride molarity on the
log axis plotted versus electrode potential (in mv) on the linear
scale. Some electrodes may be slightly nonlinear between 10−5 and
10−4 M. If this occurs, use additional standards between these two
concentrations.
10.2.3 Calibrate the fluoride electrode daily, and check it
hourly. Prepare fresh fluoride standardizing solutions daily (10−2
M or less). Store fluoride standardizing solutions in polyethylene
or polypropylene containers.
Note:
Certain specific ion meters have been designed specifically for
fluoride electrode use and give a direct readout of fluoride ion
concentration. These meters may be used in lieu of calibration
curves for fluoride measurements over a narrow concentration
ranges. Calibrate the meter according to the manufacturer's
instructions.
11.0 Analytical Procedures
11.1 Sample Loss Check, Sample Preparation, and Distillation.
Same as Method 13A, sections 11.1 through 11.3, except that the
note following section 11.3.1 is not applicable.
11.2 Analysis.
11.2.1 Containers No. 1 and No. 2. Distill suitable aliquots
from Containers No. 1 and No. 2. Dilute the distillate in the
volumetric flasks to exactly 250 ml with water, and mix thoroughly.
Pipet a 25-ml aliquot from each of the distillate into separate
beakers. Add an equal volume of TISAB, and mix. The sample should
be at the same temperature as the calibration standards when
measurements are made. If ambient laboratory temperature fluctuates
more than ±2 °C from the temperature at which the calibration
standards were measured, condition samples and standards in a
constant-temperature bath before measurement. Stir the sample with
a magnetic stirrer during measurement to minimize electrode
response time. If the stirrer generates enough heat to change
solution temperature, place a piece of temperature insulating
material, such as cork, between the stirrer and the beaker. Hold
dilute samples (below 10−4 M fluoride ion content) in polyethylene
beakers during measurement.
11.2.2 Insert the fluoride and reference electrodes into the
solution. When a steady millivolt reading is obtained, record it.
This may take several minutes. Determine concentration from the
calibration curve. Between electrode measurements, rinse the
electrode with water.
11.2.3 Container No. 3 (Silica Gel). Same as in Method 13A,
section 11.4.2.
12.0 Data Analysis and Calculations
Carry out calculations, retaining at least one extra significant
figure beyond that of the acquired data. Round off figures after
final calculation.
12.1 Nomenclature. Same as Method 13A, section 12.1, with the
addition of the following:
M = F− concentration from calibration curve, molarity.
12.2 Average DGM Temperature and Average Orifice Pressure Drop,
Dry Gas Volume, Volume of Water Vapor and Moisture Content,
Fluoride Concentration in Stack Gas, and Isokinetic Variation. Same
as Method 13A, sections 12.2 to 12.4, 12.6, and 12.7,
respectively.
12.3 Total Fluoride in Sample. Calculate the amount of F− in the
sample using Equation 13B-1:
The following estimates are based on a collaborative test done
at a primary aluminum smelter. In the test, six laboratories each
sampled the stack simultaneously using two sampling trains for a
total of 12 samples per sampling run. Fluoride concentrations
encountered during the test ranged from 0.1 to 1.4 mg F−/m 3.
13.1 Precision. The intra-laboratory and inter-laboratory
standard deviations, which include sampling and analysis errors,
are 0.037 mg F−/m 3 with 60 degrees of freedom and 0.056 mg F−/m 3
with five degrees of freedom, respectively.
13.2 Bias. The collaborative test did not find any bias in the
analytical method.
13.3 Range. The range of this method is 0.02 to 2,000 µg F−/ml;
however, measurements of less than 0.1 µg F−/ml require extra
care.
16.1 Compliance with ASTM D 3270-73T, 91, 95 “Analysis for
Fluoride Content of the Atmosphere and Plant Tissues (Semiautomated
Method)” is an acceptable alternative for the distillation and
analysis requirements specified in sections 11.1 and 11.2 when
applied to suitable aliquots of Containers 1 and 2 samples.
17.0 References
Same as Method 13A, section 16.0, References 1 and 2, with the
following addition:
1. MacLeod, Kathryn E., and Howard L. Crist. Comparison of the
SPADNS-Zirconium Lake and Specific Ion Electrode Methods of
Fluoride Determination in Stack Emission Samples. Analytical
Chemistry. 45:1272-1273. 1973.
18.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
Method 14 - Determination of Fluoride Emissions From Potroom Roof
Monitors for Primary Aluminum Plants Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, Method 5,
Method 13A, and Method 13B.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Total fluorides as
Fluorine
7782-41-4
Not determined.
1.2 Applicability. This method is applicable for the
determination of fluoride emissions from roof monitors at primary
aluminum reduction plant potroom groups.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 Gaseous and particulate fluoride roof monitor emissions are
drawn into a permanent sampling manifold through several large
nozzles. The sample is transported from the sampling manifold to
ground level through a duct. The fluoride content of the gas in the
duct is determined using either Method 13A or Method 13B. Effluent
velocity and volumetric flow rate are determined using anemometers
located in the roof monitor.
3.0 Definitions
Potroom means a building unit which houses a group of
electrolytic cells in which aluminum is produced.
Potroom group means an uncontrolled potroom, a potroom
which is controlled individually, or a group of potrooms or potroom
segments ducted to a common control system.
Roof monitor means that portion of the roof of a potroom
where gases not captured at the cell exit from the potroom.
4.0 Interferences
Same as section 4.0 of either Method 13A or Method 13B, with the
addition of the following:
4.1 Magnetic Field Effects. Anemometer readings can be affected
by potroom magnetic field effects. section 6.1 provides for
minimization of this interference through proper shielding or
encasement of anemometer components.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Corrosive Reagents. Same as section 5.2 of either Method 13A
or Method 13B.
6.0 Equipment and Supplies
Same as section 6.0 of either Method 13A or Method 13B, as
applicable, with the addition of the following:
6.1 Velocity Measurement Apparatus.
6.1.1 Anemometer Specifications. Propeller anemometers, or
equivalent. Each anemometer shall meet the following
specifications:
6.1.1.1 Its propeller shall be made of polystyrene, or similar
material of uniform density. To ensure uniformity of performance
among propellers, it is desirable that all propellers be made from
the same mold.
6.1.1.2 The propeller shall be properly balanced, to optimize
performance.
6.1.1.3 When the anemometer is mounted horizontally, its
threshold velocity shall not exceed 15 m/min (50 ft/min).
6.1.1.4 The measurement range of the anemometer shall extend to
at least 600 m/min (2,000 ft/min).
6.1.1.5 The anemometer shall be able to withstand prolonged
exposure to dusty and corrosive environments; one way of achieving
this is to purge the bearings of the anemometer continuously with
filtered air during operation.
6.1.1.6 All anemometer components shall be properly shielded or
encased, such that the performance of the anemometer is
uninfluenced by potroom magnetic field effects.
6.1.1.7 A known relationship shall exist between the electrical
output signal from the anemometer generator and the propeller shaft
rpm (see section 10.2.1). Anemometers having other types of output
signals (e.g., optical) may be used, subject to the approval
of the Administrator. If other types of anemometers are used, there
must be a known relationship between output signal and shaft rpm
(see section 10.2.2).
6.1.1.8 Each anemometer shall be equipped with a suitable
readout system (see section 6.1.3).
6.1.2 Anemometer Installation Requirements.
6.1.2.1 Single, Isolated Potroom. If the affected facility
consists of a single, isolated potroom (or potroom segment),
install at least one anemometer for every 85 m (280 ft) of roof
monitor length. If the length of the roof monitor divided by 85 m
(280 ft) is not a whole number, round the fraction to the nearest
whole number to determine the number of anemometers needed. For
monitors that are less than 130 m (430 ft) in length, use at least
two anemometers. Divide the monitor cross-section into as many
equal areas as anemometers, and locate an anemometer at the
centroid of each equal area. See exception in section 6.1.2.3.
6.1.2.2 Two or More Potrooms. If the affected facility consists
of two or more potrooms (or potroom segments) ducted to a common
control device, install anemometers in each potroom (or segment)
that contains a sampling manifold. Install at least one anemometer
for every 85 m (280 ft) of roof monitor length of the potroom (or
segment). If the potroom (or segment) length divided by 85 m (280
ft) is not a whole number, round the fraction to the nearest whole
number to determine the number of anemometers needed. If the
potroom (or segment) length is less than 130 m (430 ft), use at
least two anemometers. Divide the potroom (or segment) monitor
cross-section into as many equal areas as anemometers, and locate
an anemometer at the centroid of each equal area. See exception in
section 6.1.2.3.
6.1.2.3 Placement of Anemometer at the Center of Manifold. At
least one anemometer shall be installed in the immediate vicinity
(i.e., within 10 m (33 ft)) of the center of the manifold
(see section 6.2.1). For its placement in relation to the width of
the monitor, there are two alternatives. The first is to make a
velocity traverse of the width of the roof monitor where an
anemometer is to be placed and install the anemometer at a point of
average velocity along this traverse. The traverse may be made with
any suitable low velocity measuring device, and shall be made
during normal process operating conditions. The second alternative
is to install the anemometer half-way across the width of the roof
monitor. In this latter case, the velocity traverse need not be
conducted.
6.1.3 Recorders. Recorders that are equipped with suitable
auxiliary equipment (e.g., transducers) for converting the
output signal from each anemometer to a continuous recording of air
flow velocity or to an integrated measure of volumetric flowrate
shall be used. A suitable recorder is one that allows the output
signal from the propeller anemometer to be read to within 1 percent
when the velocity is between 100 and 120 m/min (330 and 390
ft/min). For the purpose of recording velocity, “continuous” shall
mean one readout per 15-minute or shorter time interval. A constant
amount of time shall elapse between readings. Volumetric flow rate
may be determined by an electrical count of anemometer revolutions.
The recorders or counters shall permit identification of the
velocities or flowrates measured by each individual anemometer.
6.1.4 Pitot Tube. Standard-type pitot tube, as described in
section 6.7 of Method 2, and having a coefficient of 0.99
±0.01.
6.1.5 Pitot Tube (Optional). Isolated, Type S pitot, as
described in section 6.1 of Method 2, and having a known
coefficient, determined as outlined in section 4.1 of Method 2.
6.1.6 Differential Pressure Gauge. Inclined manometer, or
equivalent, as described in section 6.1.2 of Method 2.
6.2 Roof Monitor Air Sampling System.
6.2.1 Manifold System and Ductwork. A minimum of one manifold
system shall be installed for each potroom group. The manifold
system and ductwork shall meet the following specifications:
6.2.1.1 The manifold system and connecting duct shall be
permanently installed to draw an air sample from the roof monitor
to ground level. A typical installation of a duct for drawing a
sample from a roof monitor to ground level is shown in Figure 14-1
in section 17.0. A plan of a manifold system that is located in a
roof monitor is shown in Figure 14-2. These drawings represent a
typical installation for a generalized roof monitor. The dimensions
on these figures may be altered slightly to make the manifold
system fit into a particular roof monitor, but the general
configuration shall be followed.
6.2.1.2 There shall be eight nozzles, each having a diameter of
0.40 to 0.50 m.
6.2.1.3 The length of the manifold system from the first nozzle
to the eighth shall be 35 m (115 ft) or eight percent of the length
of the potroom (or potroom segment) roof monitor, whichever is
greater. Deviation from this requirement is subject to the approval
of the Administrator.
6.2.1.4 The duct leading from the roof monitor manifold system
shall be round with a diameter of 0.30 to 0.40 m (1.0 to 1.3 ft).
All connections in the ductwork shall be leak-free.
6.2.1.5 As shown in Figure 14-2, each of the sample legs of the
manifold shall have a device, such as a blast gate or valve, to
enable adjustment of the flow into each sample nozzle.
6.2.1.6 The manifold system shall be located in the immediate
vicinity of one of the propeller anemometers (see section 8.1.1.4)
and as close as possible to the midsection of the potroom (or
potroom segment). Avoid locating the manifold system near the end
of a potroom or in a section where the aluminum reduction pot
arrangement is not typical of the rest of the potroom (or potroom
segment). The sample nozzles shall be centered in the throat of the
roof monitor (see Figure 14-1).
6.2.1.7 All sample-exposed surfaces within the nozzles,
manifold, and sample duct shall be constructed with 316 stainless
steel. Alternatively, aluminum may be used if a new ductwork is
conditioned with fluoride-laden roof monitor air for a period of
six weeks before initial testing. Other materials of construction
may be used if it is demonstrated through comparative testing, to
the satisfaction of the Administrator, that there is no loss of
fluorides in the system.
6.2.1.8 Two sample ports shall be located in a vertical section
of the duct between the roof monitor and the exhaust fan (see
section 6.2.2). The sample ports shall be at least 10 duct
diameters downstream and three diameters upstream from any flow
disturbance such as a bend or contraction. The two sample ports
shall be situated 90° apart. One of the sample ports shall be
situated so that the duct can be traversed in the plane of the
nearest upstream duct bend.
6.2.2 Exhaust Fan. An industrial fan or blower shall be attached
to the sample duct at ground level (see Figure 14-1). This exhaust
fan shall have a capacity such that a large enough volume of air
can be pulled through the ductwork to maintain an isokinetic
sampling rate in all the sample nozzles for all flow rates normally
encountered in the roof monitor. The exhaust fan volumetric flow
rate shall be adjustable so that the roof monitor gases can be
drawn isokinetically into the sample nozzles. This control of flow
may be achieved by a damper on the inlet to the exhauster or by any
other workable method.
6.3 Temperature Measurement Apparatus. To monitor and record the
temperature of the roof monitor effluent gas, and consisting of the
following:
6.3.1 Temperature Sensor. A temperature sensor shall be
installed in the roof monitor near the sample duct. The temperature
sensor shall conform to the specifications outlined in Method 2,
section 6.3.
6.3.2 Signal Transducer. Transducer, to change the temperature
sensor voltage output to a temperature readout.
6.3.3 Thermocouple Wire. To reach from roof monitor to signal
transducer and recorder.
6.3.4 Recorder. Suitable recorder to monitor the output from the
thermocouple signal transducer.
7.0 Reagents and Standards
Same as section 7.0 of either Method 13A or Method 13B, as
applicable.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Roof Monitor Velocity Determination.
8.1.1 Velocity Estimate(s) for Setting Isokinetic Flow. To
assist in setting isokinetic flow in the manifold sample nozzles,
the anticipated average velocity in the section of the roof monitor
containing the sampling manifold shall be estimated before each
test run. Any convenient means to make this estimate may be used
(e.g., the velocity indicated by the anemometer in the
section of the roof monitor containing the sampling manifold may be
continuously monitored during the 24-hour period before the test
run). If there is question as to whether a single estimate of
average velocity is adequate for an entire test run (e.g.,
if velocities are anticipated to be significantly different during
different potroom operations), the test run may be divided into two
or more “sub-runs,” and a different estimated average velocity may
be used for each sub-run (see section 8.4.2).
8.1.2 Velocity Determination During a Test Run. During the
actual test run, record the velocity or volumetric flowrate
readings of each propeller anemometer in the roof monitor. Readings
shall be taken from each anemometer at equal time intervals of 15
minutes or less (or continuously).
8.2 Temperature Recording. Record the temperature of the roof
monitor effluent gases at least once every 2 hours during the test
run.
8.3 Pretest Ductwork Conditioning. During the 24-hour period
immediately preceding the test run, turn on the exhaust fan, and
draw roof monitor air through the manifold system and ductwork.
Adjust the fan to draw a volumetric flow through the duct such that
the velocity of gas entering the manifold nozzles approximates the
average velocity of the air exiting the roof monitor in the
vicinity of the sampling manifold.
8.4.1 Initial Adjustment. Before the test run (or first sub-run,
if applicable; see sections 8.1.1 and 8.4.2), adjust the fan such
that air enters the manifold sample nozzles at a velocity equal to
the appropriate estimated average velocity determined under section
8.1.1. Use Equation 14-1 (Section 12.2.2) to determine the correct
stream velocity needed in the duct at the sampling location, in
order for sample gas to be drawn isokinetically into the manifold
nozzles. Next, verify that the correct stream velocity has been
achieved, by performing a pitot tube traverse of the sample duct
(using either a standard or Type S pitot tube); use the procedure
outlined in Method 2.
8.4.2 Adjustments During Run. If the test run is divided into
two or more “sub-runs” (see section 8.1.1), additional isokinetic
rate adjustment(s) may become necessary during the run. Any such
adjustment shall be made just before the start of a sub-run, using
the procedure outlined in section 8.4.1 above.
Note:
Isokinetic rate adjustments are not permissible during a
sub-run.
8.5 Pretest Preparation, Preliminary Determinations, Preparation
of Sampling Train, Leak-Check Procedures, Sampling Train Operation,
and Sample Recovery. Same as Method 13A, sections 8.1 through 8.6,
with the exception of the following:
8.5.1 A single train shall be used for the entire sampling run.
Alternatively, if two or more sub-runs are performed, a separate
train may be used for each sub-run; note, however, that if this
option is chosen, the area of the sampling nozzle shall be the same
(±2 percent) for each train. If the test run is divided into
sub-runs, a complete traverse of the duct shall be performed during
each sub-run.
8.5.2 Time Per Run. Each test run shall last 8 hours or more; if
more than one run is to be performed, all runs shall be of
approximately the same (±10 percent) length. If questions exist as
to the representativeness of an 8-hour test, a longer period should
be selected. Conduct each run during a period when all normal
operations are performed underneath the sampling manifold. For most
recently-constructed plants, 24 hours are required for all potroom
operations and events to occur in the area beneath the sampling
manifold. During the test period, all pots in the potroom group
shall be operated such that emissions are representative of normal
operating conditions in the potroom group.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality Control Measure
Effect
8.0, 10.0
Sampling equipment leak-check
and calibration
Ensure accurate measurement of
gas flow rate in duct and of sample volume.
10.3, 10.4
Initial and periodic
performance checks of roof monitor effluent gas characterization
apparatus
Ensure accurate and precise
measurement of roof monitor effluent gas temperature and flow
rate.
11.0
Interference/recovery
efficiency check during distillation
Minimize negative effects of
used acid.
9.2 Volume Metering System Checks. Same as Method 5, section
9.2.
10.0 Calibration and Standardization
Same as section 10.0 of either Method 13A or Method 13B, as
applicable, with the addition of the following:
10.1 Manifold Intake Nozzles. The manifold intake nozzles shall
be calibrated when the manifold system is installed or,
alternatively, the manifold may be preassembled and the nozzles
calibrated on the ground prior to installation. The following
procedures shall be observed:
10.1.1 Adjust the exhaust fan to draw a volumetric flow rate
(refer to Equation 14-1) such that the entrance velocity into each
manifold nozzle approximates the average effluent velocity in the
roof monitor.
10.1.2 Measure the velocity of the air entering each nozzle by
inserting a standard pitot tube into a 2.5 cm or less diameter hole
(see Figure 14-2) located in the manifold between each blast gate
(or valve) and nozzle. Note that a standard pitot tube is used,
rather than a type S, to eliminate possible velocity measurement
errors due to cross-section blockage in the small (0.13 m diameter)
manifold leg ducts. The pitot tube tip shall be positioned at the
center of each manifold leg duct. Take care to ensure that there is
no leakage around the pitot tube, which could affect the indicated
velocity in the manifold leg.
10.1.3 If the velocity of air being drawn into each nozzle is
not the same, open or close each blast gate (or valve) until the
velocity in each nozzle is the same. Fasten each blast gate (or
valve) so that it will remain in position, and close the pitot port
holes.
10.2 Initial Calibration of Propeller Anemometers.
10.2.1 Anemometers that meet the specifications outlined in
section 6.1.1 need not be calibrated, provided that a reference
performance curve relating anemometer signal output to air velocity
(covering the velocity range of interest) is available from the
manufacturer. If a reference performance curve is not available
from the manufacturer, such a curve shall be generated.
For the purpose of this method, a “reference” performance curve
is defined as one that has been derived from primary standard
calibration data, with the anemometer mounted vertically. “Primary
standard” data are obtainable by: (a) direct calibration of one or
more of the anemometers by the National Institute of Standards and
Technology (NIST); (b) NIST-traceable calibration; or (c)
Calibration by direct measurement of fundamental parameters such as
length and time (e.g., by moving the anemometers through
still air at measured rates of speed, and recording the output
signals).
10.2.2 Anemometers having output signals other than electrical
(e.g., optical) may be used, subject to the approval of the
Administrator. If other types of anemometers are used, a reference
performance curve shall be generated, using procedures subject to
the approval of the Administrator.
10.2.3 The reference performance curve shall be derived from at
least the following three points: 60 ±15, 900 ±100, and 1800 ±100
rpm.
10.3 Initial Performance Checks. Conduct these checks within 60
days before the first performance test.
10.3.1 Anemometers. A performance-check shall be conducted as
outlined in sections 10.3.1.1 through 10.3.1.3. Alternatively, any
other suitable method that takes into account the signal output,
propeller condition, and threshold velocity of the anemometer may
be used, subject to the approval of the Administrator.
10.3.1.1 Check the signal output of the anemometer by using an
accurate rpm generator (see Figure 14-3) or synchronous motors to
spin the propeller shaft at each of the three rpm settings
described in section 10.2.3, and measuring the output signal at
each setting. If, at each setting, the output signal is within 5
percent of the manufacturer's value, the anemometer can be used. If
the anemometer performance is unsatisfactory, the anemometer shall
either be replaced or repaired.
10.3.1.2 Check the propeller condition, by visually inspecting
the propeller, making note of any significant damage or warpage;
damaged or deformed propellers shall be replaced.
10.3.1.3 Check the anemometer threshold velocity as follows:
With the anemometer mounted as shown in Figure 14-4(A), fasten a
known weight (a straight-pin will suffice) to the anemometer
propeller at a fixed distance from the center of the propeller
shaft. This will generate a known torque; for example, a 0.1-g
weight, placed 10 cm from the center of the shaft, will generate a
torque of 1.0 g-cm. If the known torque causes the propeller to
rotate downward, approximately 90° [see Figure 14-4(B)], then the
known torque is greater than or equal to the starting torque; if
the propeller fails to rotate approximately 90°, the known torque
is less than the starting torque. By trying different combinations
of weight and distance, the starting torque of a particular
anemometer can be satisfactorily estimated. Once an estimate of the
starting torque has been obtained, the threshold velocity of the
anemometer (for horizontal mounting) can be estimated from a graph
such as Figure 14-5 (obtained from the manufacturer). If the
horizontal threshold velocity is acceptable [<15 m/min (50
ft/min), when this technique is used], the anemometer can be used.
If the threshold velocity of an anemometer is found to be
unacceptably high, the anemometer shall either be replaced or
repaired.
10.3.2 Recorders and Counters. Check the calibration of each
recorder and counter (see section 6.1.2) at a minimum of three
points, approximately spanning the expected range of velocities.
Use the calibration procedures recommended by the manufacturer, or
other suitable procedures (subject to the approval of the
Administrator). If a recorder or counter is found to be out of
calibration by an average amount greater than 5 percent for the
three calibration points, replace or repair the system; otherwise,
the system can be used.
10.3.3 Temperature Measurement Apparatus. Check the calibration
of the Temperature Measurement Apparatus, using the procedures
outlined in section 10.3 of Method 2, at temperatures of 0, 100,
and 150 °C (32, 212, and 302 °F). If the calibration is off by more
than 5 °C (9 °F) at any of the temperatures, repair or replace the
apparatus; otherwise, the apparatus can be used.
10.4 Periodic Performance Checks. Repeat the procedures outlined
in section 10.3 no more than 12 months after the initial
performance checks. If the above systems pass the performance
checks (i.e., if no repair or replacement of any component
is necessary), continue with the performance checks on a 12-month
interval basis. However, if any of the above systems fail the
performance checks, repair or replace the system(s) that failed,
and conduct the periodic performance checks on a 3-month interval
basis, until sufficient information (to the satisfaction of the
Administrator) is obtained to establish a modified performance
check schedule and calculation procedure.
Note:
If any of the above systems fails the 12-month periodic
performance checks, the data for the past year need not be
recalculated.
11.0 Analytical Procedures
Same as section 11.0 of either Method 13A or Method 13B.
12.0 Data Analysis and Calculations
Same as section 12.0 of either Method 13A or Method 13B, as
applicable, with the following additions and exceptions:
12.1 Nomenclature.
A = Roof monitor open area, m 2 (ft 2). Bws = Water vapor in the
gas stream, portion by volume. Cs = Average fluoride concentration
in roof monitor air, mg F/dscm (gr/dscf). Dd = Diameter of duct at
sampling location, m (ft). Dn = Diameter of a roof monitor manifold
nozzle, m (ft). F = Emission Rate multiplication factor,
dimensionless. Ft = Total fluoride mass collected during a
particular sub-run (from Equation 13A-1 of Method 13A or Equation
13B-1 of Method 13B), mg F− (gr F−). Md = Mole fraction of dry gas,
dimensionless. Prm = Pressure in the roof monitor; equal to
barometric pressure for this application. Qsd = Average volumetric
flow from roof monitor at standard conditions on a dry basis, m
3/min. Trm = Average roof monitor temperature (from section 8.2),
°C ( °F). Vd = Desired velocity in duct at sampling location,
m/sec. Vm = Anticipated average velocity (from section 8.1.1) in
sampling duct, m/sec. Vmt = Arithmetic mean roof monitor effluent
gas velocity, m/sec. Vs = Actual average velocity in the sampling
duct (from Equation 2-9 of Method 2 and data obtained from Method
13A or 13B), m/sec.
12.2 Isokinetic Sampling Check.
12.2.1 Calculate the arithmetic mean of the roof monitor
effluent gas velocity readings (vm) as measured by the anemometer
in the section of the roof monitor containing the sampling
manifold. If two or more sub-runs have been performed, the average
velocity for each sub-run may be calculated separately.
12.2.2 Calculate the expected average velocity (vd) in the duct,
corresponding to each value of vm obtained under section 12.2.1,
using Equation 14-1.
Where: 8 = number of required manifold nozzles.
60 = sec/min.
12.2.3 Calculate the actual average velocity (vs) in the
sampling duct for each run or sub-run according to Equation 2-9 of
Method 2, using data obtained during sampling (Section 8.0 of
Method 13A).
12.2.4 Express each vs value from section 12.2.3 as a percentage
of the corresponding vd value from section 12.2.2.
12.2.4.1 If vs is less than or equal to 120 percent of vd, the
results are acceptable (note that in cases where the above
calculations have been performed for each sub-run, the results are
acceptable if the average percentage for all sub-runs is less than
or equal to 120 percent).
12.2.4.2 If vs is more than 120 percent of vd, multiply the
reported emission rate by the following factor:
12.3 Average Velocity of Roof Monitor Effluent Gas. Calculate
the arithmetic mean roof monitor effluent gas velocity (vmt) using
all the velocity or volumetric flow readings from section
8.1.2.
12.4 Average Temperature of Roof Monitor Effluent Gas. Calculate
the arithmetic mean roof monitor effluent gas temperature (Tm)
using all the temperature readings recorded in section 8.2.
12.5 Concentration of Fluorides in Roof Monitor Effluent
Gas.
12.5.1 If a single sampling train was used throughout the run,
calculate the average fluoride concentration for the roof monitor
using Equation 13A-2 of Method 13A.
12.5.2 If two or more sampling trains were used (i.e.,
one per sub-run), calculate the average fluoride concentration for
the run using Equation 14-3:
Where: n = Total number of sub-runs.
12.6 Mole Fraction of Dry Gas.
12.7 Average Volumetric Flow Rate of Roof Monitor Effluent Gas.
Calculate the arithmetic mean volumetric flow rate of the roof
monitor effluent gases using Equation 14-5.
Where: K1 = 0.3858 K/mm Hg for metric units, =
17.64 °R/in. Hg for English units. 13.0 Method Performance
[Reserved] 14.0 Pollution Prevention [Reserved] 15.0 Waste
Management [Reserved] 16.0 References
Same as section 16.0 of either Method 13A or Method 13B, as
applicable, with the addition of the following:
1. Shigehara, R.T. A Guideline for Evaluating Compliance Test
Results (Isokinetic Sampling Rate Criterion). U.S. Environmental
Protection Agency, Emission Measurement Branch, Research Triangle
Park, NC. August 1977.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 14A -
Determination of Total Fluoride Emissions from Selected Sources at
Primary Aluminum Production Facilities Note:
This method does not include all the specifications (e.g.,
equipment and supplies) and procedures (e.g., sampling) essential
to its performance. Some material is incorporated by reference from
other methods in this part. Therefore, to obtain reliable results,
persons using this method should have a thorough knowledge of at
least the following additional test methods: Method 5, Methods 13A
and 13B, and Method 14 of this appendix.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Total
fluorides
None assigned
Not determined.
Includes hydrogen
fluoride
007664-39-3
Not determined.
1.2 Applicability. This method is applicable for the
determination of total fluorides (TF) emissions from sources
specified in the applicable regulation. This method was developed
by consensus with the Aluminum Association and the U.S.
Environmental Protection Agency (EPA).
2.0 Summary of Method
2.1 Total fluorides, in the form of solid and gaseous fluorides,
are withdrawn from the ascending air stream inside of an aluminum
reduction potroom and, prior to exiting the potroom roof monitor,
into a specific cassette arrangement. The cassettes are connected
by tubing to flowmeters and a manifold system that allows for the
equal distribution of volume pulled through each cassette, and
finally to a dry gas meter. The cassettes have a specific internal
arrangement of one unaltered cellulose filter and support pad in
the first section of the cassette for solid fluoride retention and
two cellulose filters with support pads that are impregnated with
sodium formate for the chemical absorption of gaseous fluorides in
the following two sections of the cassette. A minimum of eight
cassettes shall be used for a potline and shall be strategically
located at equal intervals across the potroom roof so as to
encompass a minimum of 8 percent of the total length of the
potroom. A greater number of cassettes may be used should the
regulated facility choose to do so. The mass flow rate of
pollutants is determined with anemometers and temperature sensing
devices located immediately below the opening of the roof monitor
and spaced evenly within the cassette group.
3.0 Definitions
3.1 Cassette. A segmented, styrene acrylonitrile cassette
configuration with three separate segments and a base, for the
purpose of this method, to capture and retain fluoride from potroom
gases.
3.2 Cassette arrangement. The cassettes, tubing, manifold
system, flowmeters, dry gas meter, and any other related equipment
associated with the actual extraction of the sample gas stream.
3.3 Cassette group. That section of the potroom roof monitor
where a distinct group of cassettes is located.
3.4 Potline. A single, discrete group of electrolytic reduction
cells electrically connected in series, in which alumina is reduced
to form aluminum.
3.5 Potroom. A building unit that houses a group of electrolytic
reduction cells in which aluminum is produced.
3.6 Potroom group. An uncontrolled potroom, a potroom that is
controlled individually, or a group of potrooms or potroom segments
ducted to a common primary control system.
3.7 Primary control system. The equipment used to capture the
gases and particulate matter generated during the reduction process
and the emission control device(s) used to remove pollutants prior
to discharge of the cleaned gas to the atmosphere.
3.8 Roof monitor. That portion of the roof of a potroom building
where gases, not captured at the cell, exit from the potroom.
3.9 Total fluorides (TF). Elemental fluorine and all fluoride
compounds as measured by Methods 13A or 13B of this appendix or by
an approved alternative method.
4.0 Interferences and Known Limitations
4.1 There are two principal categories of limitations that must
be addressed when using this method. The first category is sampling
bias and the second is analytical bias. Biases in sampling can
occur when there is an insufficient number of cassettes located
along the roof monitor of a potroom or if the distribution of those
cassettes is spatially unequal. Known sampling biases also can
occur when there are leaks within the cassette arrangement and if
anemometers and temperature devices are not providing accurate
data. Applicable instruments must be properly calibrated to avoid
sampling bias. Analytical biases can occur when instrumentation is
not calibrated or fails calibration and the instrument is used out
of proper calibration. Additionally, biases can occur in the
laboratory if fusion crucibles retain residual fluorides over
lengthy periods of use. This condition could result in falsely
elevated fluoride values. Maintaining a clean work environment in
the laboratory is crucial to producing accurate values.
4.2 Biases during sampling can be avoided by properly spacing
the appropriate number of cassettes along the roof monitor,
conducting leak checks of the cassette arrangement, calibrating the
dry gas meter every 30 days, verifying the accuracy of individual
flowmeters (so that there is no more than 5 percent difference in
the volume pulled between any two flowmeters), and calibrating or
replacing anemometers and temperature sensing devices as necessary
to maintain true data generation.
4.3 Analytical biases can be avoided by calibrating instruments
according to the manufacturer's specifications prior to conducting
any analyses, by performing internal and external audits of up to
10 percent of all samples analyzed, and by rotating individual
crucibles as the “blank” crucible to detect any potential residual
fluoride carry-over to samples. Should any contamination be
discovered in the blank crucible, the crucible shall be thoroughly
cleaned to remove any detected residual fluorides and a “blank”
analysis conducted again to evaluate the effectiveness of the
cleaning. The crucible shall remain in service as long as no
detectable residual fluorides are present.
5.0 Safety
5.1 This method may involve the handling of hazardous materials
in the analytical phase. This method does not purport to address
all of the potential safety hazards associated with its use. It is
the responsibility of the user to establish appropriate safety and
health practices and determine the applicability of regulatory
limitations prior to performing this test method.
5.2 Corrosive reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water for at least 15 minutes. Remove
clothing under shower and decontaminate. Treat residual chemical
burn as thermal burn.
5.3 Sodium Hydroxide (NaOH). Causes severe damage to eyes and
skin. Inhalation causes irritation to nose, throat, and lungs.
Reacts exothermically with limited amounts of water.
5.4 Perchloric Acid (HClO4). Corrosive to eyes, skin, nose, and
throat. Provide ventilation to limit exposure. Very strong
oxidizer. Keep separate from water and oxidizable materials to
prevent vigorous evolution of heat, spontaneous combustion, or
explosion. Heat solutions containing HClO4 only in hoods
specifically designed for HClO4.
6.0 Equipment and Supplies
6.1 Sampling.
6.1.1 Cassette arrangement. The cassette itself is a
three-piece, styrene acrylonitrile cassette unit (a Gelman Sciences
product), 37 millimeter (mm), with plastic connectors. In the first
section (the intake section), an untreated Gelman Sciences 37 mm,
0.8 micrometer (µm) DM-800 metricel membrane filter and cellulose
support pad, or equivalent, is situated. In the second and third
segments of the cassette there is placed one each of Gelman
Sciences 37 mm, 5 µm GLA-5000 low-ash PVC filter with a cellulose
support pad or equivalent product. Each of these two filters and
support pads shall have been immersed in a solution of 10 percent
sodium formate (volume/volume in an ethyl alcohol solution). The
impregnated pads shall be placed in the cassette segments while
still wet and heated at 50 °C (122 °F) until the pad is completely
dry. It is important to check for a proper fit of the filter and
support pad to the cassette segment to ensure that there are no
areas where gases could bypass the filter. Once all of the cassette
segments have been prepared, the cassette shall be assembled and a
plastic plug shall be inserted into the exhaust hole of the
cassette. Prior to placing the cassette into service, the space
between each segment shall be taped with an appropriately durable
tape to prevent the infiltration of gases through the points of
connection, and an aluminum nozzle shall be inserted into the
intake hole of the cassette. The aluminum nozzle shall have a short
section of tubing placed over the opening of the nozzle, with the
tubing plugged to prevent dust from entering the nozzle and to
prepare the nozzle for the cassette arrangement leak check. An
alternate nozzle type can be used if historical results or
scientific demonstration of applicability can be shown.
6.1.2 Anemometers and temperature sensing devices. To calculate
the mass flow rate of TF from the roof monitor under standard
conditions, anemometers that meet the specifications in section
2.1.1 in Method 14 of this appendix or an equivalent device
yielding equivalent information shall be used. A recording
mechanism capable of accurately recording the exit gas temperature
at least every 2 hours shall be used.
6.1.3 Barometer. To correct the volumetric flow from the potline
roof monitor to standard conditions, a mercury (Hg), aneroid, or
other barometer capable of measuring atmospheric pressure to within
2.5 mm [0.1 inch (in)] Hg shall be used.
Note:
The barometric reading may be obtained from a nearby National
Weather Service Station. In this case, the station value (which is
absolute barometric pressure) shall be requested and an adjustment
for elevation differences between the weather station and the
sampling point shall be made at a rate of minus 2.5 mm (0.1 in) Hg
per 30 meters (m) [100 feet (ft)] elevation increase or plus 2.5 mm
(0.1 in) Hg per 30 m (100 ft) elevation decrease.
6.2 Sample recovery.
6.2.1 Hot plate.
6.2.2 Muffle furnace.
6.2.3 Nickel crucible.
6.2.4 Stirring rod. Teflon.
6.2.5 Volumetric flask. 50-milliliter (ml).
6.2.6 Plastic vial. 50-ml.
6.3 Analysis.
6.3.1 Primary analytical method. An automated analyzer having
the following components or equivalent: a multichannel
proportioning pump, multiposition sampler, voltage stabilizer,
colorimeter, instrument recording device, microdistillation
apparatus, flexible Teflon ® heating bath, vacuum pump, pulse
suppressers and an air flow system.
6.3.2 Secondary analytical method. Specific Ion Electrode
(SIE).
7.0 Reagents and Standards
7.1 Water. Deionized distilled to conform to ASTM Specification
D 1193-77, Type 3 (incorporated by reference in § 60.17(a)(22) of
this part). The KMnO4 test for oxidizable organic matter may be
omitted when high concentrations of organic matter are not expected
to be present.
7.2 Calcium oxide.
7.3 Sodium hydroxide (NaOH). Pellets.
7.4 Perchloric acid (HClO4). Mix 1:1 with water. Sulfuric acid
(H2SO4) may be used in place of HClO4.
7.5 Audit samples. The audit samples discussed in section 9.1
shall be prepared from reagent grade, water soluble stock reagents,
or purchased as an aqueous solution from a commercial supplier. If
the audit stock solution is purchased from a commercial supplier,
the standard solution must be accompanied by a certificate of
analysis or an equivalent proof of fluoride concentration.
8.0 Sample Collection and Analysis
8.1 Preparing cassette arrangement for sampling. The cassettes
are initially connected to flexible tubing. The tubing is connected
to flowmeters and a manifold system. The manifold system is
connected to a dry gas meter (Research Appliance Company model
201009 or equivalent). The length of tubing is managed by
pneumatically or electrically operated hoists located in the roof
monitor, and the travel of the tubing is controlled by encasing the
tubing in aluminum conduit. The tubing is lowered for cassette
insertion by operating a control box at floor level. Once the
cassette has been securely inserted into the tubing and the leak
check performed, the tubing and cassette are raised to the roof
monitor level using the floor level control box. Arrangements
similar to the one described are acceptable if the scientific
sample collection principles are followed.
8.2 Test run sampling period. A test run shall comprise a
minimum of a 24-hour sampling event encompassing at least eight
cassettes per potline (or four cassettes per potroom group).
Monthly compliance shall be based on three test runs during the
month. Test runs of greater than 24 hours are allowed; however,
three such runs shall be conducted during the month.
8.3 Leak-check procedures.
8.3.1 Pretest leak check. A pretest leak-check is recommended;
however, it is not required. To perform a pretest leak-check after
the cassettes have been inserted into the tubing, isolate the
cassette to be leak-checked by turning the valves on the manifold
to stop all flows to the other sampling points connected to the
manifold and meter. The cassette, with the plugged tubing section
securing the intake of the nozzle, is subjected to the highest
vacuum expected during the run. If no leaks are detected, the
tubing plug can be briefly removed as the dry gas meter is rapidly
turned off.
8.3.2 Post-test leak check. A leak check is required at the
conclusion of each test run for each cassette. The leak check shall
be performed in accordance with the procedure outlined in section
8.3.1 of this method except that it shall be performed at a vacuum
greater than the maximum vacuum reached during the test run. If the
leakage rate is found to be no greater than 4 percent of the
average sampling rate, the results are acceptable. If the leakage
rate is greater than 4 percent of the average sampling rate, either
record the leakage rate and correct the sampling volume as
discussed in section 12.4 of this method or void the test run if
the minimum number of cassettes were used. If the number of
cassettes used was greater than the minimum required, discard the
leaking cassette and use the remaining cassettes for the emission
determination.
8.3.3 Anemometers and temperature sensing device placement.
Install the recording mechanism to record the exit gas temperature.
Anemometers shall be installed as required in section 6.1.2 of
Method 14 of this appendix, except replace the word “manifold” with
“cassette group” in section 6.1.2.3. These two different
instruments shall be located near each other along the roof
monitor. See conceptual configurations in Figures 14A-1, 14A-2, and
14A-3 of this method. Fewer temperature devices than anemometers
may be used if at least one temperature device is located within
the span of the cassette group. Other anemometer location siting
scenarios may be acceptable as long as the exit velocity of the
roof monitor gases is representative of the entire section of the
potline being sampled.
8.4 Sampling. The actual sample run shall begin with the removal
of the tubing and plug from the cassette nozzle. Each cassette is
then raised to the roof monitor area, the dry gas meter is turned
on, and the flowmeters are set to the calibration point, which
allows an equal volume of sampled gas to enter each cassette. The
dry gas meter shall be set to a range suitable for the specific
potroom type being sampled that will yield valid data known from
previous experience or a range determined by the use of the
calculation in section 12 of this method. Parameters related to the
test run that shall be recorded, either during the test run or
after the test run if recording devices are used, include:
anemometer data, roof monitor exit gas temperature, dry gas meter
temperature, dry gas meter volume, and barometric pressure. At the
conclusion of the test run, the cassettes shall be lowered, the dry
gas meter turned off, and the volume registered on the dry gas
meter recorded. The post-test leak check procedures described in
section 8.3.2 of this method shall be performed. All data relevant
to the test shall be recorded on a field data sheet and maintained
on file.
8.5 Sample recovery.
8.5.1 The cassettes shall be brought to the laboratory with the
intake nozzle contents protected with the section of plugged tubing
previously described. The exterior of cassettes shall carefully be
wiped free of any dust or debris, making sure that any falling dust
or debris does not present a potential laboratory contamination
problem.
8.5.2 Carefully remove all tape from the cassettes and remove
the initial filter, support pad, and all loose solids from the
first (intake) section of the cassette. Fold the filter and support
pad several times and, along with all loose solids removed from the
interior of the first section of the cassette, place them into a
nickel crucible. Using water, wash the interior of the nozzle into
the same nickel crucible. Add 0.1 gram (g) [±0.1 milligram (mg)] of
calcium oxide and a sufficient amount of water to make a loose
slurry. Mix the contents of the crucible thoroughly with a Teflon”
stirring rod. After rinsing any adhering residue from the stirring
rod back into the crucible, place the crucible on a hot plate or in
a muffle furnace until all liquid is evaporated and allow the
mixture to gradually char for 1 hour.
8.5.3 Transfer the crucible to a cold muffle furnace and ash at
600 °C (1,112 °F). Remove the crucible after the ashing phase and,
after the crucible cools, add 3.0 g (±0.1 g) of NaOH pellets. Place
this mixture in a muffle furnace at 600 °C (1,112 °F) for 3
minutes. Remove the crucible and roll the melt so as to reach all
of the ash with the molten NaOH. Let the melt cool to room
temperature. Add 10 to 15 ml of water to the crucible and place it
on a hot plate at a low temperature setting until the melt is soft
or suspended. Transfer the contents of the crucible to a 50-ml
volumetric flask. Rinse the crucible with 20 ml of 1:1 perchloric
acid or 20 ml of 1:1 sulfuric acid in two (2) 10 ml portions. Pour
the acid rinse slowly into the volumetric flask and swirl the flask
after each addition. Cool to room temperature. The product of this
procedure is particulate fluorides.
8.5.4 Gaseous fluorides can be isolated for analysis by folding
the gaseous fluoride filters and support pads to approximately 1/4
of their original size and placing them in a 50-ml plastic vial. To
the vial add exactly 10 ml of water and leach the sample for a
minimum of 1 hour. The leachate from this process yields the
gaseous fluorides for analysis.
9.0 Quality Control
9.1 Laboratory auditing. Laboratory audits of specific and known
concentrations of fluoride shall be submitted to the laboratory
with each group of samples submitted for analysis. An auditor shall
prepare and present the audit samples as a “blind” evaluation of
laboratory performance with each group of samples submitted to the
laboratory. The audits shall be prepared to represent
concentrations of fluoride that could be expected to be in the low,
medium and high range of actual results. Average recoveries of all
three audits must equal 90 to 110 percent for acceptable results;
otherwise, the laboratory must investigate procedures and
instruments for potential problems.
Note:
The analytical procedure allows for the analysis of individual
or combined filters and pads from the cassettes provided that equal
volumes (±10 percent) are sampled through each cassette.
10.0 Calibrations
10.1 Equipment evaluations. To ensure the integrity of this
method, periodic calibrations and equipment replacements are
necessary.
10.1.1 Metering system. At 30-day intervals the metering system
shall be calibrated. Connect the metering system inlet to the
outlet of a wet test meter that is accurate to 1 percent. Refer to
Figure 5-4 of Method 5 of this appendix. The wet-test meter shall
have a capacity of 30 liters/revolution [1 cubic foot (ft
3)/revolution]. A spirometer of 400 liters (14 ft 3) or more
capacity, or equivalent, may be used for calibration; however, a
wet-test meter is usually more practical. The wet-test meter shall
be periodically tested with a spirometer or a liquid displacement
meter to ensure the accuracy. Spirometers or wet-test meters of
other sizes may be used, provided that the specified accuracies of
the procedure are maintained. Run the metering system pump for
about 15 min. with the orifice manometer indicating a median
reading as expected in field use to allow the pump to warm up and
to thoroughly wet the interior of the wet-test meter. Then, at each
of a minimum of three orifice manometer settings, pass an exact
quantity of gas through the wet-test meter and record the volume
indicated by the dry gas meter. Also record the barometric
pressure, the temperatures of the wet test meter, the inlet
temperatures of the dry gas meter, and the temperatures of the
outlet of the dry gas meter. Record all calibration data on a form
similar to the one shown in Figure 5-5 of Method 5 of this appendix
and calculate Y, the dry gas meter calibration factor, and ΔH@, the
orifice calibration factor at each orifice setting. Allowable
tolerances for Y and ΔH@ are given in Figure 5-6 of Method 5 of
this appendix. Allowable tolerances for Y and ΔH@ are given in
Figure 5-5 of Method 5 of this appendix.
10.1.2 Estimating volumes for initial test runs. For a
facility's initial test runs, the regulated facility must have a
target or desired volume of gases to be sampled and a target range
of volumes to use during the calibration of the dry gas meter. Use
Equations 14A-1 and 14A-2 in section 12 of this method to derive
the target dry gas meter volume (Fv) for these purposes.
10.1.3 Calibration of anemometers and temperature sensing
devices. If the standard anemometers in Method 14 of this appendix
are used, the calibration and integrity evaluations in sections
10.3.1.1 through 10.3.1.3 of Method 14 of this appendix shall be
used as well as the recording device described in section 2.1.3 of
Method 14. The calibrations or complete change-outs of anemometers
shall take place at a minimum of once per year. The temperature
sensing and recording devices shall be calibrated according to the
manufacturer's specifications.
10.1.4 Calibration of flowmeters. The calibration of flowmeters
is necessary to ensure that an equal volume of sampled gas is
entering each of the individual cassettes and that no large
differences, which could possibly bias the sample, exist between
the cassettes.
10.1.4.1 Variable area, 65 mm flowmeters or equivalent shall be
used. These flowmeters can be mounted on a common base for
convenience. These flowmeters shall be calibrated by attaching a
prepared cassette, complete with filters and pads, to the flowmeter
and then to the system manifold. This manifold is an aluminum
cylinder with valved inlets for connections to the
flowmeters/cassettes and one outlet to a dry gas meter. The
connection is then made to the wet-test meter and finally to a dry
gas meter. All connections are made with tubing.
10.1.4.2 Turn the dry gas meter on for 15 min. in preparation
for the calibration. Turn the dry gas meter off and plug the intake
hole of the cassette. Turn the dry gas meter back on to evaluate
the entire system for leaks. If the dry gas meter shows a leakage
rate of less than 0.02 ft 3/min at 10 in. of Hg vacuum as noted on
the dry gas meter, the system is acceptable to further
calibration.
10.1.4.3 With the dry gas meter turned on and the flow indicator
ball at a selected flow rate, record the exact amount of gas pulled
through the flowmeter by taking measurements from the wet test
meter after exactly 10 min. Record the room temperature and
barometric pressure. Conduct this test for all flowmeters in the
system with all flowmeters set at the same indicator ball reading.
When all flowmeters have gone through the procedure above, correct
the volume pulled through each flowmeter to standard conditions.
The acceptable difference between the highest and lowest flowmeter
rate is 5 percent. Should one or more flowmeters be outside of the
acceptable limit of 5 percent, repeat the calibration procedure at
a lower or higher indicator ball reading until all flowmeters show
no more than 5 percent difference among them.
10.1.4.4 This flowmeter calibration shall be conducted at least
once per year.
10.1.5 Miscellaneous equipment calibrations. Miscellaneous
equipment used such as an automatic recorder/ printer used to
measure dry gas meter temperatures shall be calibrated according to
the manufacturer's specifications in order to maintain the accuracy
of the equipment.
11.0 Analytical Procedure
11.1 The preferred primary analytical determination of the
individual isolated samples or the combined particulate and gaseous
samples shall be performed by an automated methodology. The
analytical method for this technology shall be based on the
manufacturer's instructions for equipment operation and shall also
include the analysis of five standards with concentrations in the
expected range of the actual samples. The results of the analysis
of the five standards shall have a coefficient of correlation of at
least 0.99. A check standard shall be analyzed as the last sample
of the group to determine if instrument drift has occurred. The
acceptable result for the check standard is 95 to 105 percent of
the standard's true value.
11.2 The secondary analytical method shall be by specific ion
electrode if the samples are distilled or if a TISAB IV buffer is
used to eliminate aluminum interferences. Five standards with
concentrations in the expected range of the actual samples shall be
analyzed, and a coefficient of correlation of at least 0.99 is the
minimum acceptable limit for linearity. An exception for this limit
for linearity is a condition when low-level standards in the range
of 0.01 to 0.48 µg fluoride/ml are analyzed. In this situation, a
minimum coefficient of correlation of 0.97 is required. TISAB II
shall be used for low-level analyses.
12.0 Data Analysis and Calculations
12.1 Carry out calculations, retaining at least one extra
decimal point beyond that of the acquired data. Round off values
after the final calculation. Other forms of calculations may be
used as long as they give equivalent results.
12.2 Estimating volumes for initial test runs.
Where Fv
= Desired volume of dry gas to be sampled, ft 3. Fd = Desired or
analytically optimum mass of TF per cassette, micrograms of TF per
cassette (µg/cassette). X = Number of cassettes used. Fe = Typical
concentration of TF in emissions to be sampled, µg/ft 3, calculated
from Equation 14A-2. Where Re = Typical
emission rate from the facility, pounds of TF per ton (lb/ton) of
aluminum. Rp = Typical production rate of the facility, tons of
aluminum per minute (ton/min). Vr = Typical exit velocity of the
roof monitor gases, feet per minute (ft/min). Ar = Open area of the
roof monitor, square feet (ft 2).
12.2.1 Example calculation. Assume that the typical emission
rate (Re) is 1.0 lb TF/ton of aluminum, the typical roof vent gas
exit velocity (Vr) is 250 ft/min, the typical production rate (Rp)
is 0.10 ton/min, the known open area for the roof monitor (Ar) is
8,700 ft 2, and the desired (analytically optimum) mass of TF per
cassette is 1,500 µg. First calculate the concentration of TF per
cassette (Fe) in µg/ft 3 using Equation 14A-2. Then calculate the
desired volume of gas to be sampled (Fv) using Equation 14A-1.
This is a total of 575.40 ft 3 for eight cassettes or 71.925 ft
3/cassette.
12.3 Calculations of TF emissions from field and laboratory data
that would yield a production related emission rate can be
calculated as follows:
12.3.1 Obtain a standard cubic feet (scf) value for the volume
pulled through the dry gas meter for all cassettes by using the
field and calibration data and Equation 5-1 of Method 5 of this
appendix.
12.3.2 Derive the average quantity of TF per cassette (in µg
TF/cassette) by adding all laboratory data for all cassettes and
dividing this value by the total number of cassettes used. Divide
this average TF value by the corrected dry gas meter volume for
each cassette; this value then becomes TFstd (µg/ft 3).
12.3.3 Calculate the production-based emission rate (Re) in
lb/ton using Equation 14A-5.
12.3.4 As an example calculation, assume eight cassettes located
in a potline were used to sample for 72 hours during the run. The
analysis of all eight cassettes yielded a total of 3,000 µg of TF.
The dry gas meter volume was corrected to yield a total of 75 scf
per cassette, which yields a value for TFstd of 3,000/75 = 5 µg/ft
3. The open area of the roof monitor for the potline (Ar) is 17,400
ft 2. The exit velocity of the roof monitor gases (Vr) is 250
ft/min. The production rate of aluminum over the previous 720 hours
was 5,000 tons, which is 6.94 tons/hr or 0.116 ton/min (Rp).
Substituting these values into Equation 14A-5 yields:
12.4 Corrections to volumes due to leakage. Should the post-test
leak check leakage rate exceed 4 percent as described in section
8.3.2 of this method, correct the volume as detailed in Case I in
section 6.3 of Method 5 of this appendix.
Method 15 -
Determination of Hydrogen Sulfide, Carbonyl Sulfide, and Carbon
Disulfide Emissions From Stationary Sources Note:
This method is not inclusive with respect to specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of gas chromatography
techniques.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
(See Sec 13.2)
Carbon disulfide
[CS2]
75-15-0
0.5 ppmv
Carbonyl sulfide
[COS]
463-58-1
0.5 ppmv
Hydrogen sulfide
[H2S]
7783-06-4
0.5 ppmv
1.2 Applicability.
1.2.1 This method applies to the determination of emissions of
reduced sulfur compounds from tail gas control units of sulfur
recovery plants, H2S in fuel gas for fuel gas combustion devices,
and where specified in other applicable subparts of the
regulations.
1.2.2 The method described below uses the principle of gas
chromatographic (GC) separation and flame photometric detection
(FPD). Since there are many systems or sets of operating conditions
that represent useable methods for determining sulfur emissions,
all systems which employ this principle, but differ only in details
of equipment and operation, may be used as alternative methods,
provided that the calibration precision and sample-line loss
criteria are met.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A gas sample is extracted from the emission source and
diluted with clean dry air (if necessary). An aliquot of the
diluted sample is then analyzed for CS2, COS, and H2S by
GC/FPD.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Moisture Condensation. Moisture condensation in the sample
delivery system, the analytical column, or the FPD burner block can
cause losses or interferences. This potential is eliminated by
heating the probe, filter box, and connections, and by maintaining
the SO2 scrubber in an ice water bath. Moisture is removed in the
SO2 scrubber and heating the sample beyond this point is not
necessary provided the ambient temperature is above 0 °C (32 °F).
Alternatively, moisture may be eliminated by heating the sample
line, and by conditioning the sample with dry dilution air to lower
its dew point below the operating temperature of the GC/FPD
analytical system prior to analysis.
4.2 Carbon Monoxide (CO) and Carbon Dioxide (CO2). CO and CO2
have substantial desensitizing effects on the FPD even after 9:1
dilution. (Acceptable systems must demonstrate that they have
eliminated this interference by some procedure such as eluting CO
and CO2 before any of the sulfur compounds to be measured.)
Compliance with this requirement can be demonstrated by submitting
chromatograms of calibration gases with and without CO2 in the
diluent gas. The CO2 level should be approximately 10 percent for
the case with CO2 present. The two chromatograms should show
agreement within the precision limits of section 13.3.
4.3 Elemental Sulfur. The condensation of sulfur vapor in the
sampling system can lead to blockage of the particulate filter.
This problem can be minimized by observing the filter for buildup
and changing as needed.
4.4 Sulfur Dioxide (SO2). SO2 is not a specific interferent but
may be present in such large amounts that it cannot be effectively
separated from the other compounds of interest. The SO2 scrubber
described in section 6.1.3 will effectively remove SO2 from the
sample.
4.5 Alkali Mist. Alkali mist in the emissions of some control
devices may cause a rapid increase in the SO2 scrubber pH,
resulting in low sample recoveries. Replacing the SO2 scrubber
contents after each run will minimize the chances of interference
in these cases.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test to establish appropriate
safety and health practices and determine the applicability of
regulatory limitations to performing this test.
6.0 Equipment and Supplies
6.1 Sample Collection. See Figure 15-1. The sampling train
component parts are discussed in the following sections:
6.1.1 Probe. The probe shall be made of Teflon or Teflon-lined
stainless steel and heated to prevent moisture condensation. It
shall be designed to allow calibration gas to enter the probe at or
near the sample point entry. Any portion of the probe that contacts
the stack gas must be heated to prevent moisture condensation. The
probe described in section 6.1.1 of Method 16A having a nozzle
directed away from the gas stream is recommended for sources having
particulate or mist emissions. Where very high stack temperatures
prohibit the use of Teflon probe components, glass or quartz-lined
probes may serve as substitutes.
6.1.2 Particulate Filter. 50-mm Teflon filter holder and a 1- to
2-micron porosity Teflon filter (available through Savillex
Corporation, 5325 Highway 101, Minnetonka, Minnesota 55343). The
filter holder must be maintained in a hot box at a temperature of
at least 120 °C (248 °F).
6.1.3 SO2 Scrubber. Three 300-ml Teflon segment impingers
connected in series with flexible, thick-walled, Teflon tubing.
(Impinger parts and tubing available through Savillex.) The first
two impingers contain 100 ml of citrate buffer, and the third
impinger is initially dry. The tip of the tube inserted into the
solution should be constricted to less than 3-mm ( 1/8-in.) ID and
should be immersed to a depth of at least 50 cm (2 in.). Immerse
the impingers in an ice water bath and maintain near 0 °C. The
scrubber solution will normally last for a 3-hour run before
needing replacement. This will depend upon the effects of moisture
and particulate matter on the solution strength and pH. Connections
between the probe, particulate filter, and SO2 scrubber shall be
made of Teflon and as short in length as possible. All portions of
the probe, particulate filter, and connections prior to the SO2
scrubber (or alternative point of moisture removal) shall be
maintained at a temperature of at least 120 °C (248 °F).
6.1.4 Sample Line. Teflon, no greater than 13-mm ( 1/2-in.) ID.
Alternative materials, such as virgin Nylon, may be used provided
the line-loss test is acceptable.
6.1.5 Sample Pump. The sample pump shall be a leakless
Teflon-coated diaphragm type or equivalent.
6.2 Analysis. The following items are needed for sample
analysis:
6.2.1 Dilution System. The dilution system must be constructed
such that all sample contacts are made of Teflon, glass, or
stainless steel. It must be capable of approximately a 9:1 dilution
of the sample.
6.2.2 Gas Chromatograph (see Figure 15-2). The gas chromatograph
must have at least the following components:
6.2.2.1 Oven. Capable of maintaining the separation column at
the proper operating temperature ±1 °C.
6.2.2.2 Temperature Gauge. To monitor column oven, detector, and
exhaust temperature ±1 °C.
6.2.2.3 Flow System. Gas metering system to measure sample,
fuel, combustion gas, and carrier gas flows.
6.2.2.4 Flame Photometric Detector.
6.2.2.4.1 Electrometer. Capable of full scale amplification of
linear ranges of 10−9 to 10−4 amperes full scale.
6.2.2.4.2 Power Supply. Capable of delivering up to 750
volts.
6.2.2.5 Recorder. Compatible with the output voltage range of
the electrometer.
6.2.2.6 Rotary Gas Valves. Multiport Teflon-lined valves
equipped with sample loop. Sample loop volumes shall be chosen to
provide the needed analytical range. Teflon tubing and fittings
shall be used throughout to present an inert surface for sample
gas. The GC shall be calibrated with the sample loop used for
sample analysis.
6.2.2.7 GC Columns. The column system must be demonstrated to be
capable of resolving three major reduced sulfur compounds: H2S,
COS, and CS2. To demonstrate that adequate resolution has been
achieved, a chromatogram of a calibration gas containing all three
reduced sulfur compounds in the concentration range of the
applicable standard must be submitted. Adequate resolution will be
defined as base line separation of adjacent peaks when the
amplifier attenuation is set so that the smaller peak is at least
50 percent of full scale. Base line separation is defined as a
return to zero (±5 percent) in the interval between peaks. Systems
not meeting this criteria may be considered alternate methods
subject to the approval of the Administrator.
6.3 Calibration System (See Figure 15-3). The calibration system
must contain the following components:
6.3.1 Flow System. To measure air flow over permeation tubes
within 2 percent. Each flowmeter shall be calibrated after each
complete test series with a wet-test meter. If the flow measuring
device differs from the wet-test meter by more than 5 percent, the
completed test shall be discarded. Alternatively, use the flow data
that will yield the lowest flow measurement. Calibration with a
wet-test meter before a test is optional. Flow over the permeation
device may also be determined using a soap bubble flowmeter.
6.3.2 Constant Temperature Bath. Device capable of maintaining
the permeation tubes at the calibration temperature within 0.1
°C.
6.3.3 Temperature Sensor. Thermometer or equivalent to monitor
bath temperature within 0.1 °C.
7.0 Reagents and Standards
7.1 Fuel. Hydrogen gas (H2). Prepurified grade or better.
7.2 Combustion Gas. Oxygen (O2) or air, research purity or
better.
7.3 Carrier Gas. Prepurified grade or better.
7.4 Diluent. Air containing less than 0.5 ppmv total sulfur
compounds and less than 10 ppmv each of moisture and total
hydrocarbons.
7.5 Calibration Gases.
7.5.1 Permeation Devices. One each of H2S, COS, and CS2,
gravimetrically calibrated and certified at some convenient
operating temperature. These tubes consist of hermetically sealed
FEP Teflon tubing in which a liquified gaseous substance is
enclosed. The enclosed gas permeates through the tubing wall at a
constant rate. When the temperature is constant, calibration gases
covering a wide range of known concentrations can be generated by
varying and accurately measuring the flow rate of diluent gas
passing over the tubes. These calibration gases are used to
calibrate the GC/FPD system and the dilution system.
7.5.2 Cylinder Gases. Cylinder gases may be used as alternatives
to permeation devices. The gases must be traceable to a primary
standard (such as permeation tubes) and not used beyond the
certification expiration date.
7.6 Citrate Buffer. Dissolve 300 g of potassium citrate and 41 g
of anhydrous citric acid in 1 liter of water. Alternatively, 284 g
of sodium citrate may be substituted for the potassium citrate.
Adjust the pH to between 5.4 and 5.6 with potassium citrate or
citric acid, as required.
8.0 Sample Collection, Preservation, Transport, and Storage
8.1 Pretest Procedures. After the complete measurement system
has been set up at the site and deemed to be operational, the
following procedures should be completed before sampling is
initiated. These procedures are not required, but would be helpful
in preventing any problem which might occur later to invalidate the
entire test.
8.1.1 Leak-Check. Appropriate leak-check procedures should be
employed to verify the integrity of all components, sample lines,
and connections. The following procedure is suggested: For
components upstream of the sample pump, attach the probe end of the
sample line to a manometer or vacuum gauge, start the pump and pull
a vacuum greater than 50 mm (2 in.) Hg, close off the pump outlet,
and then stop the pump and ascertain that there is no leak for 1
minute. For components after the pump, apply a slight positive
pressure and check for leaks by applying a liquid (detergent in
water, for example) at each joint. Bubbling indicates the presence
of a leak. As an alternative to the initial leak-test, the sample
line loss test described in section 8.3.1 may be performed to
verify the integrity of components.
8.1.2 System Performance. Since the complete system is
calibrated at the beginning and end of each day of testing, the
precise calibration of each component is not critical. However,
these components should be verified to operate properly. This
verification can be performed by observing the response of
flowmeters or of the GC output to changes in flow rates or
calibration gas concentrations, respectively, and ascertaining the
response to be within predicted limits. If any component or the
complete system fails to respond in a normal and predictable
manner, the source of the discrepancy should be identified and
corrected before proceeding.
8.2 Sample Collection and Analysis
8.2.1 After performing the calibration procedures outlined in
section 10.0, insert the sampling probe into the test port ensuring
that no dilution air enters the stack through the port. Begin
sampling and dilute the sample approximately 9:1 using the dilution
system. Note that the precise dilution factor is the one determined
in section 10.4. Condition the entire system with sample for a
minimum of 15 minutes before beginning the analysis. Inject
aliquots of the sample into the GC/FPD analyzer for analysis.
Determine the concentration of each reduced sulfur compound
directly from the calibration curves or from the equation for the
least-squares line.
8.2.2 If reductions in sample concentrations are observed during
a sample run that cannot be explained by process conditions, the
sampling must be interrupted to determine if the probe or filter is
clogged with particulate matter. If either is found to be clogged,
the test must be stopped and the results up to that point
discarded. Testing may resume after cleaning or replacing the probe
and filter. After each run, the probe and filter shall be inspected
and, if necessary, replaced.
8.2.3 A sample run is composed of 16 individual analyses
(injects) performed over a period of not less than 3 hours or more
than 6 hours.
8.3 Post-Test Procedures.
8.3.1 Sample Line Loss. A known concentration of H2S at the
level of the applicable standard, ±20 percent, must be introduced
into the sampling system at the opening of the probe in sufficient
quantities to ensure that there is an excess of sample which must
be vented to the atmosphere. The sample must be transported through
the entire sampling system to the measurement system in the same
manner as the emission samples. The resulting measured
concentration is compared to the known value to determine the
sampling system loss. For sampling losses greater than 20 percent,
the previous sample run is not valid. Sampling losses of 0-20
percent must be corrected by dividing the resulting sample
concentration by the fraction of recovery. The known gas sample may
be calibration gas as described in section 7.5. Alternatively,
cylinder gas containing H2S mixed in nitrogen and verified
according to section 7.1.4 of Method 16A may be used. The optional
pretest procedures provide a good guideline for determining if
there are leaks in the sampling system.
8.3.2 Determination of Calibration Drift. After each run, or
after a series of runs made within a 24-hour period, perform a
partial recalibration using the procedures in section 10.0. Only
H2S (or other permeant) need be used to recalibrate the GC/FPD
analysis system and the dilution system. Partial recalibration may
be performed at the midlevel calibration gas concentration or at a
concentration measured in the samples but not less than the lowest
calibration standard used in the initial calibration. Compare the
calibration curves obtained after the runs to the calibration
curves obtained under section 10.3. The calibration drift should
not exceed the limits set forth in section 13.4. If the drift
exceeds this limit, the intervening run or runs should be
considered invalid. As an option, the calibration data set that
gives the highest sample values may be chosen by the tester.
9.0 Quality Control
Section
Quality control measure
Effect
8.3.1
Sample line loss check
Ensures that uncorrected
negative bias introduced by sample loss is no greater than 20
percent, and provides for correction of bias of 20 percent or
less.
8.3.2
Calibration drift test
Ensures that bias introduced
by drift in the measurement system output during the run is no
greater than 5 percent.
10.0
Analytical calibration
Ensures precision of
analytical results within 5 percent.
10.0 Calibration and Standardization
Prior to any sampling run, calibrate the system using the
following procedures. (If more than one run is performed during any
24-hour period, a calibration need not be performed prior to the
second and any subsequent runs. However, the calibration drift must
be determined as prescribed in section 8.3.2 after the last run is
made within the 24-hour period.)
Note:
This section outlines steps to be followed for use of the GC/FPD
and the dilution system. The calibration procedure does not include
detailed instructions because the operation of these systems is
complex, and it requires an understanding of the individual system
being used. Each system should include a written operating manual
describing in detail the operating procedures associated with each
component in the measurement system. In addition, the operator
should be familiar with the operating principles of the components,
particularly the GC/FPD. The references in section 16.0 are
recommended for review for this purpose.
10.1 Calibration Gas Permeation Tube Preparation.
10.1.1 Insert the permeation tubes into the tube chamber. Check
the bath temperature to assure agreement with the calibration
temperature of the tubes within 0.1 °C. Allow 24 hours for the
tubes to equilibrate. Alternatively, equilibration may be verified
by injecting samples of calibration gas at 1-hour intervals. The
permeation tubes can be assumed to have reached equilibrium when
consecutive hourly samples agree within 5 percent of their
mean.
10.1.2 Vary the amount of air flowing over the tubes to produce
the desired concentrations for calibrating the analytical and
dilution systems. The air flow across the tubes must at all times
exceed the flow requirement of the analytical systems. The
concentration in ppmv generated by a tube containing a specific
permeant can be calculated using Equation 15-1 in section 12.2.
10.2 Calibration of Analytical System. Generate a series of
three or more known concentrations spanning the linear range of the
FPD (approximately 0.5 to 10 ppmv for a 1-ml sample) for each of
the three major sulfur compounds. Bypassing the dilution system,
inject these standards into the GC/FPD and monitor the responses
until three consecutive injections for each concentration agree
within 5 percent of their mean. Failure to attain this precision
indicates a problem in the calibration or analytical system. Any
such problem must be identified and corrected before
proceeding.
10.3 Calibration Curves. Plot the GC/FPD response in current
(amperes) versus their causative concentrations in ppmv on log-log
coordinate graph paper for each sulfur compound. Alternatively, a
least-squares equation may be generated from the calibration data
using concentrations versus the appropriate instrument response
units.
10.4 Calibration of Dilution System. Generate a known
concentration of H2S using the permeation tube system. Adjust the
flow rate of diluent air for the first dilution stage so that the
desired level of dilution is approximated. Inject the diluted
calibration gas into the GC/FPD system until the results of three
consecutive injections for each dilution agree within 5 percent of
their mean. Failure to attain this precision in this step is an
indication of a problem in the dilution system. Any such problem
must be identified and corrected before proceeding. Using the
calibration data for H2S (developed under section 10.3), determine
the diluted calibration gas concentration in ppmv. Then calculate
the dilution factor as the ratio of the calibration gas
concentration before dilution to the diluted calibration gas
concentration determined under this section. Repeat this procedure
for each stage of dilution required. Alternatively, the GC/FPD
system may be calibrated by generating a series of three or more
concentrations of each sulfur compound and diluting these samples
before injecting them into the GC/FPD system. These data will then
serve as the calibration data for the unknown samples and a
separate determination of the dilution factor will not be
necessary. However, the precision requirements are still
applicable.
11.0 Analytical Procedure
Sample collection and analysis are concurrent for this method
(see section 8.0).
12.0 Data Analysis and Calculations
12.1 Nomenclature.
C = Concentration of permeant produced, ppmv. COS = Carbonyl
sulfide concentration, ppmv. CS2 = Carbon disulfide concentration,
ppmv. d = Dilution factor, dimensionless. H2S = Hydrogen sulfide
concentration, ppmv. K = 24.04 L/g mole. (Gas constant at 20 °C and
760 mm Hg) L = Flow rate, L/min, of air over permeant 20 °C, 760 mm
Hg. M = Molecular weight of the permeant, g/g-mole. N = Number of
analyses performed. Pr = Permeation rate of the tube, µg/min.
12.2 Permeant Concentration. Calculate the concentration
generated by a tube containing a specific permeant (see section
10.1) using the following equation:
12.3 Calculation of SO2 Equivalent. SO2 equivalent will be
determined for each analysis made by summing the concentrations of
each reduced sulfur compound resolved during the given analysis.
The SO2 equivalent is expressed as SO2 in ppmv.
12.4 Average SO2 Equivalent. This is determined using the
following equation. Systems that do not remove moisture from the
sample but condition the gas to prevent condensation must correct
the average SO2 equivalent for the fraction of water vapor present.
This is not done under applications where the emission standard is
not specified on a dry basis.
Where: Avg SO2 equivalent = Average SO2
equivalent in ppmv, dry basis. Average SO2 equivalent i = SO2 in
ppmv as determined by Equation 15-2. 13.0 Method Performance
13.1 Range. Coupled with a GC system using a 1-ml sample size,
the maximum limit of the FPD for each sulfur compound is
approximately 10 ppmv. It may be necessary to dilute samples from
sulfur recovery plants a hundredfold (99:1), resulting in an upper
limit of about 1000 ppmv for each compound.
13.2 Sensitivity. The minimum detectable concentration of the
FPD is also dependent on sample size and would be about 0.5 ppmv
for a 1-ml sample.
13.3 Calibration Precision. A series of three consecutive
injections of the same calibration gas, at any dilution, shall
produce results which do not vary by more than 5 percent from the
mean of the three injections.
13.4 Calibration Drift. The calibration drift determined from
the mean of three injections made at the beginning and end of any
run or series of runs within a 24-hour period shall not exceed 5
percent.
1. O'Keeffe, A.E., and G.C. Ortman. “Primary Standards for Trace
Gas Analysis.” Anal. Chem. 38,760. 1966.
2. Stevens, R.K., A.E. O'Keeffe, and G.C. Ortman. “Absolute
Calibration of a Flame Photometric Detector to Volatile Sulfur
Compounds at Sub-Part-Per-Million Levels.” Environmental Science
and Technology 3:7. July 1969.
3. Mulik, J.D., R.K. Stevens, and R. Baumgardner. “An Analytical
System Designed to Measure Multiple Malodorous Compounds Related to
Kraft Mill Activities.” Presented at the 12th Conference on Methods
in Air Pollution and Industrial Hygiene Studies, University of
Southern California, Los Angeles, CA, April 6-8, 1971.
4. Devonald, R.H., R.S. Serenius, and A.D. McIntyre. “Evaluation
of the Flame Photometric Detector for Analysis of Sulfur
Compounds.” Pulp and Paper Magazine of Canada, 73,3. March
1972.
5. Grimley, K.W., W.S. Smith, and R.M. Martin. “The Use of a
Dynamic Dilution System in the Conditioning of Stack Gases for
Automated Analysis by a Mobile Sampling Van.” Presented at the 63rd
Annual APCA Meeting in St. Louis, MO. June 14-19, 1970.
6. General Reference. Standard Methods of Chemical Analysis
Volume III-A and III-B: Instrumental Analysis. Sixth Edition. Van
Nostrand Reinhold Co.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 15A -
Determination of Total Reduced Sulfur Emissions From Sulfur
Recovery Plants in Petroleum Refineries Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 6, Method 15, and Method
16A.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Reduced sulfur
compounds
None assigned
Not determined.
1.2 Applicability. This method is applicable for the
determination of emissions of reduced sulfur compounds from sulfur
recovery plants where the emissions are in a reducing atmosphere,
such as in Stretford units.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 An integrated gas sample is extracted from the stack, and
combustion air is added to the oxygen (O2)-deficient gas at a known
rate. The reduced sulfur compounds [including carbon disulfide
(CS2), carbonyl sulfide (COS), and hydrogen sulfide (H2S)] are
thermally oxidized to sulfur dioxide (SO2), which is then collected
in hydrogen peroxide as sulfate ion and analyzed according to the
Method 6 barium-thorin titration procedure.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Reduced sulfur compounds, other than CS2, COS, and H2S, that
are present in the emissions will also be oxidized to SO2, causing
a positive bias relative to emission standards that limit only the
three compounds listed above. For example, thiophene has been
identified in emissions from a Stretford unit and produced a
positive bias of 30 percent in the Method 15A result. However,
these biases may not affect the outcome of the test at units where
emissions are low relative to the standard.
4.2 Calcium and aluminum have been shown to interfere in the
Method 6 titration procedure. Since these metals have been
identified in particulate matter emissions from Stretford units, a
Teflon filter is required to minimize this interference.
4.3 Dilution of the hydrogen peroxide (H2O2) absorbing solution
can potentially reduce collection efficiency, causing a negative
bias. When used to sample emissions containing 7 percent moisture
or less, the midget impingers have sufficient volume to contain the
condensate collected during sampling. Dilution of the H2O2 does not
affect the collection of SO2. At higher moisture contents, the
potassium citrate-citric acid buffer system used with Method 16A
should be used to collect the condensate.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Corrosive reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water for at least 15 minutes. Remove
clothing under shower and decontaminate. Treat residual chemical
burns as thermal burns.
5.2.1 Hydrogen Peroxide (H2O2). Irritating to eyes, skin, nose,
and lungs.
5.2.2 Sodium Hydroxide (NaOH). Causes severe damage to eyes and
skin. Inhalation causes irritation to nose, throat, and lungs.
Reacts exothermically with limited amounts of water.
5.2.3 Sulfuric Acid (H2SO4). Rapidly destructive to body tissue.
Will cause third degree burns. Eye damage may result in blindness.
Inhalation may be fatal from spasm of the larynx, usually within 30
minutes. May cause lung tissue damage with edema. 3 mg/m 3 will
cause lung damage in uninitiated. 1 mg/m 3 for 8 hours will cause
lung damage or, in higher concentrations, death. Provide
ventilation to limit inhalation. Reacts violently with metals and
organics.
6.0 Equipment and Supplies
6.1 Sample Collection. The sampling train used in performing
this method is shown in Figure 15A-1, and component parts are
discussed below. Modifications to this sampling train are
acceptable provided that the system performance check is met.
6.1.1 Probe. 6.4-mm ( 1/4-in.) OD Teflon tubing sequentially
wrapped with heat-resistant fiber strips, a rubberized heating tape
(with a plug at one end), and heat-resistant adhesive tape. A
flexible thermocouple or some other suitable temperature-measuring
device shall be placed between the Teflon tubing and the fiber
strips so that the temperature can be monitored. The probe should
be sheathed in stainless steel to provide in-stack rigidity. A
series of bored-out stainless steel fittings placed at the front of
the sheath will prevent flue gas from entering between the probe
and sheath. The sampling probe is depicted in Figure 15A-2.
6.1.2 Particulate Filter. A 50-mm Teflon filter holder and a 1-
to 2-mm porosity Teflon filter (available through Savillex
Corporation, 5325 Highway 101, Minnetonka, Minnesota 55345). The
filter holder must be maintained in a hot box at a temperature high
enough to prevent condensation.
6.1.3 Combustion Air Delivery System. As shown in the schematic
diagram in Figure 15A-3. The rate meter should be selected to
measure an air flow rate of 0.5 liter/min (0.02 ft 3/min).
6.1.4 Combustion Tube. Quartz glass tubing with an expanded
combustion chamber 2.54 cm (1 in.) in diameter and at least 30.5 cm
(12 in.) long. The tube ends should have an outside diameter of 0.6
cm ( 1/4 in.) and be at least 15.3 cm (6 in.) long. This length is
necessary to maintain the quartz-glass connector near ambient
temperature and thereby avoid leaks. Alternatively, the outlet may
be constructed with a 90 degree glass elbow and socket that would
fit directly onto the inlet of the first peroxide impinger.
6.1.5 Furnace. Of sufficient size to enclose the combustion
tube. The furnace must have a temperature regulator capable of
maintaining the temperature at 1100 ±50 °C (2,012 ±90 °F). The
furnace operating temperature must be checked with a thermocouple
to ensure accuracy. Lindberg furnaces have been found to be
satisfactory.
6.1.6 Peroxide Impingers, Stopcock Grease, Temperature Sensor,
Drying Tube, Valve, Pump, and Barometer. Same as in Method 6,
sections 6.1.1.2, 6.1.1.4, 6.1.1.5, 6.1.1.6, 6.1.1.7, 6.1.1.8, and
6.1.2, respectively, except that the midget bubbler of Method 6,
section 6.1.1.2 is not required.
6.1.7 Vacuum Gauge and Rate Meter. At least 760 mm Hg (30 in.
Hg) gauge and rotameter, or equivalent, capable of measuring flow
rate to ±5 percent of the selected flow rate and calibrated as in
section 10.2.
6.1.8 Volume Meter. Dry gas meter capable of measuring the
sample volume under the particular sampling conditions with an
accuracy of 2 percent.
6.1.9 U-tube manometer. To measure the pressure at the exit of
the combustion gas dry gas meter.
6.2 Sample Recovery and Analysis. Same as Method 6, sections 6.2
and 6.3, except a 10-ml buret with 0.05-ml graduations is required
for titrant volumes of less than 10.0 ml, and the spectrophotometer
is not needed.
7.0 Reagents and Standards Note:
Unless otherwise indicated, all reagents must conform to the
specifications established by the Committee on Analytical Reagents
of the American Chemical Society. When such specifications are not
available, the best available grade shall be used.
7.1 Sample Collection. The following reagents and standards are
required for sample analysis:
7.1.1 Water. Same as Method 6, section 7.1.1.
7.1.2 Hydrogen Peroxide (H2O2), 3 Percent by Volume. Same as
Method 6, section 7.1.3 (40 ml is needed per sample).
7.1.3 Recovery Check Gas. Carbonyl sulfide in nitrogen [100
parts per million by volume (ppmv) or greater, if necessary] in an
aluminum cylinder. Concentration certified by the manufacturer with
an accuracy of ±2 percent or better, or verified by gas
chromatography where the instrument is calibrated with a COS
permeation tube.
7.1.4 Combustion Gas. Air, contained in a gas cylinder equipped
with a two-stage regulator. The gas shall contain less than 50 ppb
of reduced sulfur compounds and less than 10 ppm total
hydrocarbons.
7.2 Sample Recovery and Analysis. Same as Method 6, sections 7.2
and 7.3.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Preparation of Sampling Train. For the Method 6 part of the
train, measure 20 ml of 3 percent H2O2 into the first and second
midget impingers. Leave the third midget impinger empty and add
silica gel to the fourth impinger. Alternatively, a silica gel
drying tube may be used in place of the fourth impinger. Place
crushed ice and water around all impingers. Maintain the oxidation
furnace at 1100 ±50 °C (2,012 ±90 °F) to ensure 100 percent
oxidation of COS. Maintain the probe and filter temperatures at a
high enough level (no visible condensation) to prevent moisture
condensation and monitor the temperatures with a thermocouple.
8.2 Leak-Check Procedure. Assemble the sampling train and
leak-check as described in Method 6, section 8.2. Include the
combustion air delivery system from the needle valve forward in the
leak-check.
8.3 Sample Collection. Adjust the pressure on the second stage
of the regulator on the combustion air cylinder to 10 psig. Adjust
the combustion air flow rate to 0.5 ±0.05 L/min (1.1 ±0.1 ft 3/hr)
before injecting combustion air into the sampling train. Then
inject combustion air into the sampling train, start the sample
pump, and open the stack sample gas valve. Carry out these three
operations within 15 to 30 seconds to avoid pressurizing the
sampling train. Adjust the total sample flow rate to 2.0 ±0.2 L/min
(4.2 ±0.4 ft 3/hr). These flow rates produce an O2 concentration of
5.0 percent in the stack gas, which must be maintained constantly
to allow oxidation of reduced sulfur compounds to SO2. Adjust these
flow rates during sampling as necessary. Monitor and record the
combustion air manometer reading at regular intervals during the
sampling period. Sample for 1 or 3 hours. At the end of sampling,
turn off the sample pump and combustion air simultaneously (within
30 seconds of each other). All other procedures are the same as in
Method 6, section 8.3, except that the sampling train should not be
purged. After collecting the sample, remove the probe from the
stack and conduct a leak-check according to the procedures outlined
in section 8.2 of Method 6 (mandatory). After each 3-hour test run
(or after three 1-hour samples), conduct one system performance
check (see section 8.5). After this system performance check and
before the next test run, it is recommended that the probe be
rinsed and brushed and the filter replaced.
Note:
In Method 15, a test run is composed of 16 individual analyses
(injects) performed over a period of not less than 3 hours or more
than 6 hours. For Method 15A to be consistent with Method 15, the
following may be used to obtain a test run: (1) Collect three
60-minute samples or (2) collect one 3-hour sample. (Three test
runs constitute a test.)
8.4 Sample Recovery. Recover the hydrogen peroxide-containing
impingers as detailed in Method 6, section 8.4.
8.5 System Performance Check.
8.5.1 A system performance check is done (1) to validate the
sampling train components and procedure (before testing, optional)
and (2) to validate a test run (after a run, mandatory). Perform a
check in the field before testing consisting of at least two
samples (optional), and perform an additional check after each
3-hour run or after three 1-hour samples (mandatory).
8.5.2 The checks involve sampling a known concentration of COS
and comparing the analyzed concentration with the known
concentration. Mix the recovery gas with N2 as shown in Figure
15A-4 if dilution is required. Adjust the flow rates to generate a
COS concentration in the range of the stack gas or within 20
percent of the applicable standard at a total flow rate of at least
2.5 L/min (5.3 ft 3/hr). Use Equation 15A-4 (see section 12.5) to
calculate the concentration of recovery gas generated. Calibrate
the flow rate from both sources with a soap bubble flow tube so
that the diluted concentration of COS can be accurately calculated.
Collect 30-minute samples, and analyze in the same manner as the
emission samples. Collect the samples through the probe of the
sampling train using a manifold or some other suitable device that
will ensure extraction of a representative sample.
8.5.3 The recovery check must be performed in the field before
replacing the particulate filter and before cleaning the probe. A
sample recovery of 100 ±20 percent must be obtained for the data to
be valid and should be reported with the emission data, but should
not be used to correct the data. However, if the performance check
results do not affect the compliance or noncompliance status of the
affected facility, the Administrator may decide to accept the
results of the compliance test. Use Equation 15A-5 (see section
12.6) to calculate the recovery efficiency.
9.0 Quality Control
Section
Quality control measure
Effect
8.5
System performance check
Ensures validity of sampling
train components and analytical procedure.
8.2, 10.0
Sampling equipment leak-check
and calibration
Ensures accurate measurement
of stack gas flow rate, sample volume.
10.0
Barium standard solution
standardization
Ensures precision of normality
determination.
11.1
Replicate titrations
Ensures precision of titration
determinations.
10.0 Calibration and Standardization
10.1 Metering System, Temperature Sensors, Barometer, and Barium
Perchlorate Solution. Same as Method 6, sections 10.1, 10.2, 10.4,
and 10.5, respectively.
10.2 Rate Meter. Calibrate with a bubble flow tube.
11.0 Analytical Procedure
11.1 Sample Loss Check and Sample Analysis. Same as Method 6,
sections 11.1 and 11.2.
12.0 Data Analysis and Calculations
In the calculations, retain at least one extra decimal figure
beyond that of the acquired data. Round off figures after final
calculations.
12.1 Nomenclature.
CCOS = Concentration of COS recovery gas, ppm. CRG(act) = Actual
concentration of recovery check gas (after dilution), ppm. CRG(m) =
Measured concentration of recovery check gas generated, ppm. CRS =
Concentration of reduced sulfur compounds as SO2, dry basis,
corrected to standard conditions, ppm. N = Normality of barium
perchlorate titrant, milliequivalents/ml. Pbar = Barometric
pressure at exit orifice of the dry gas meter, mm Hg. Pstd =
Standard absolute pressure, 760 mm Hg. QCOS = Flow rate of COS
recovery gas, liters/min. QN = Flow rate of diluent N2, liters/min.
R = Recovery efficiency for the system performance check, percent.
Tm = Average dry gas meter absolute temperature, °K. Tstd =
Standard absolute temperature, 293 °K. Va = Volume of sample
aliquot titrated, ml. Vms = Dry gas volume as measured by the
sample train dry gas meter, liters. Vmc = Dry gas volume as
measured by the combustion air dry gas meter, liters. Vms(std) =
Dry gas volume measured by the sample train dry gas meter,
corrected to standard conditions, liters. Vmc(std) = Dry gas volume
measured by the combustion air dry gas meter, corrected to standard
conditions, liters. Vsoln = Total volume of solution in which the
sulfur dioxide sample is contained, 100 ml. Vt = Volume of barium
perchlorate titrant used for the sample (average of replicate
titrations), ml. Vtb = Volume of barium perchlorate titrant used
for the blank, ml. Y = Calibration factor for sampling train dry
gas meter. Yc = Calibration factor for combustion air dry gas
meter. 32.03 = Equivalent weight of sulfur dioxide, mg/meq.
12.2 Dry Sample Gas Volume, Corrected to Standard
Conditions.
Where: K1 = 0.3855 °K/mm Hg for metric units, =
17.65 °R/in. Hg for English units.
12.3 Combustion Air Gas Volume, corrected to Standard
Conditions.
Note:
Correct Pbar for the average pressure of the manometer during
the sampling period.
12.4 Concentration of reduced sulfur compounds as ppm SO2.
Where:
12.5 Concentration of Generated Recovery Gas.
12.6 Recovery Efficiency for the System Performance Check.
13.0 Method Performance
13.1 Analytical Range. The lower detectable limit is 0.1 ppmv
when sampling at 2 lpm for 3 hours or 0.3 ppmv when sampling at 2
lpm for 1 hour. The upper concentration limit of the method exceeds
concentrations of reduced sulfur compounds generally encountered in
sulfur recovery plants.
13.2 Precision. Relative standard deviations of 2.8 and 6.9
percent have been obtained when sampling a stream with a reduced
sulfur compound concentration of 41 ppmv as SO2 for 1 and 3 hours,
respectively.
13.3 Bias. No analytical bias has been identified. However,
results obtained with this method are likely to contain a positive
bias relative to emission regulations due to the presence of
nonregulated sulfur compounds (that are present in petroleum) in
the emissions. The magnitude of this bias varies accordingly, and
has not been quantified.
1. American Society for Testing and Materials Annual Book of
ASTM Standards. Part 31: Water, Atmospheric Analysis. Philadelphia,
Pennsylvania. 1974. pp. 40-42.
2. Blosser, R.O., H.S. Oglesby, and A.K. Jain. A Study of
Alternate SO2 Scrubber Designs Used for TRS Monitoring. National
Council of the Paper Industry for Air and Stream Improvement, Inc.,
New York, New York. Special Report 77-05. July 1977.
3. Curtis, F., and G.D. McAlister. Development and Evaluation of
an Oxidation/Method 6 TRS Emission Sampling Procedure. Emission
Measurement Branch, Emission Standards and Engineering Division,
U.S. Environmental Protection Agency, Research Triangle Park, North
Carolina. February 1980.
4. Gellman, I. A Laboratory and Field Study of Reduced Sulfur
Sampling and Monitoring Systems. National Council of the Paper
Industry for Air and Stream Improvement, Inc., New York, New York.
Atmospheric Quality Improvement Technical Bulletin No. 81. October
1975.
5. Margeson, J.H., et al. A Manual Method for TRS Determination.
Journal of Air Pollution Control Association. 35:1280-1286.
December 1985.
17.0 Tables, Diagrams, Flowcharts, and Validation Data [36 FR 24877, Dec.
23, 1971] Editorial Note:For Federal Register citations affecting
appendix A-5 to part 60, see the List of CFR sections Affected,
which appears in the Finding Aids section of the printed volume and
at www.govinfo.gov.
Appendix A-6 to Part 60 - Test Methods 16 through 18
40:9.0.1.1.1.0.1.1.6 : Appendix A
Appendix A-6 to Part 60 - Test Methods 16 through 18 Method 16 -
Semicontinuous determination of sulfur emissions from stationary
sources Method 16A - Determination of total reduced sulfur
emissions from stationary sources (impinger technique) Method 16B -
Determination of total reduced sulfur emissions from stationary
sources Method 16C - Determination of Total Reduced Sulfur
Emissions From Stationary Sources Method 17 - Determination of
particulate emissions from stationary sources (in-stack filtration
method) Method 18 - Measurement of gaseous organic compound
emissions by gas chromatography
The test methods in this appendix are referred to in § 60.8
(Performance Tests) and § 60.11 (Compliance With Standards and
Maintenance Requirements) of 40 CFR part 60, subpart A (General
Provisions). Specific uses of these test methods are described in
the standards of performance contained in the subparts, beginning
with Subpart D.
Within each standard of performance, a section title “Test
Methods and Procedures” is provided to: (1) Identify the test
methods to be used as reference methods to the facility subject to
the respective standard and (2) identify any special instructions
or conditions to be followed when applying a method to the
respective facility. Such instructions (for example, establish
sampling rates, volumes, or temperatures) are to be used either in
addition to, or as a substitute for procedures in a test method.
Similarly, for sources subject to emission monitoring requirements,
specific instructions pertaining to any use of a test method as a
reference method are provided in the subpart or in Appendix B.
Inclusion of methods in this appendix is not intended as an
endorsement or denial of their applicability to sources that are
not subject to standards of performance. The methods are
potentially applicable to other sources; however, applicability
should be confirmed by careful and appropriate evaluation of the
conditions prevalent at such sources.
The approach followed in the formulation of the test methods
involves specifications for equipment, procedures, and performance.
In concept, a performance specification approach would be
preferable in all methods because this allows the greatest
flexibility to the user. In practice, however, this approach is
impractical in most cases because performance specifications cannot
be established. Most of the methods described herein, therefore,
involve specific equipment specifications and procedures, and only
a few methods in this appendix rely on performance criteria.
Minor changes in the test methods should not necessarily affect
the validity of the results and it is recognized that alternative
and equivalent methods exist. section 60.8 provides authority for
the Administrator to specify or approve (1) equivalent methods, (2)
alternative methods, and (3) minor changes in the methodology of
the test methods. It should be clearly understood that unless
otherwise identified all such methods and changes must have prior
approval of the Administrator. An owner employing such methods or
deviations from the test methods without obtaining prior approval
does so at the risk of subsequent disapproval and retesting with
approved methods.
Within the test methods, certain specific equipment or
procedures are recognized as being acceptable or potentially
acceptable and are specifically identified in the methods. The
items identified as acceptable options may be used without approval
but must be identified in the test report. The potentially
approvable options are cited as “subject to the approval of the
Administrator” or as “or equivalent.” Such potentially approvable
techniques or alternatives may be used at the discretion of the
owner without prior approval. However, detailed descriptions for
applying these potentially approvable techniques or alternatives
are not provided in the test methods. Also, the potentially
approvable options are not necessarily acceptable in all
applications. Therefore, an owner electing to use such potentially
approvable techniques or alternatives is responsible for: (1)
assuring that the techniques or alternatives are in fact applicable
and are properly executed; (2) including a written description of
the alternative method in the test report (the written method must
be clear and must be capable of being performed without additional
instruction, and the degree of detail should be similar to the
detail contained in the test methods); and (3) providing any
rationale or supporting data necessary to show the validity of the
alternative in the particular application. Failure to meet these
requirements can result in the Administrator's disapproval of the
alternative.
Method 16 - Semicontinuous Determination of Sulfur Emissions From
Stationary Sources Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 4, Method 15, and Method
16A.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Dimethyl disulfide
[(CH3)2S2]
62-49-20
50 ppb.
Dimethyl sulfide
[(CH3)2S]
75-18-3
50 ppb.
Hydrogen sulfide
[H2S]
7783-06-4
50 ppb.
Methyl mercaptan
[CH4S]
74-93-1
50 ppb.
1.2 Applicability. This method is applicable for the
determination of total reduced sulfur (TRS) compounds from recovery
furnaces, lime kilns, and smelt dissolving tanks at kraft pulp
mills and fuel gas combustion devices at petroleum refineries.
Note:
The method described below uses the principle of gas
chromatographic (GC) separation and flame photometric detection
(FPD). Since there are many systems or sets of operating conditions
that represent useable methods of determining sulfur emissions, all
systems which employ this principle, but differ only in details of
equipment and operation, may be used as alternative methods,
provided that the calibration precision and sample line loss
criteria are met.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A gas sample is extracted from the emission source and an
aliquot is analyzed for hydrogen sulfide (H2S), methyl mercaptan
(MeSH), dimethyl sulfide (DMS), and dimethyl disulfide (DMDS) by
GC/FPD. These four compounds are known collectively as TRS.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Moisture. Moisture condensation in the sample delivery
system, the analytical column, or the FPD burner block can cause
losses or interferences. This is prevented by maintaining the
probe, filter box, and connections at a temperature of at least 120
°C (248 °F). Moisture is removed in the SO2 scrubber and heating
the sample beyond this point is not necessary when the ambient
temperature is above 0 °C (32 °F). Alternatively, moisture may be
eliminated by heating the sample line, and by conditioning the
sample with dry dilution air to lower its dew point below the
operating temperature of the GC/FPD analytical system prior to
analysis.
4.2 Carbon Monoxide (CO) and Carbon Dioxide (CO2). CO and CO2
have a substantial desensitizing effect on the flame photometric
detector even after dilution. Acceptable systems must demonstrate
that they have eliminated this interference by some procedure such
as eluting these compounds before any of the compounds to be
measured. Compliance with this requirement can be demonstrated by
submitting chromatograms of calibration gases with and without CO2
in the diluent gas. The CO2 level should be approximately 10
percent for the case with CO2 present. The two chromatograms should
show agreement within the precision limits of section 10.2.
4.3 Particulate Matter. Particulate matter in gas samples can
cause interference by eventual clogging of the analytical system.
This interference is eliminated by using the Teflon filter after
the probe.
4.4 Sulfur Dioxide (SO2). Sulfur dioxide is not a specific
interferant but may be present in such large amounts that it cannot
effectively be separated from the other compounds of interest. The
SO2 scrubber described in section 6.1.3 will effectively remove SO2
from the sample.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Hydrogen Sulfide. A flammable, poisonous gas with the odor
of rotten eggs. H2S is extremely hazardous and can cause collapse,
coma, and death within a few seconds of one or two inhalations at
sufficient concentrations. Low concentrations irritate the mucous
membranes and may cause nausea, dizziness, and headache after
exposure.
6.0 Equipment and Supplies
6.1. Sample Collection. The following items are needed for
sample collection.
6.1.1 Probe. Teflon or Teflon-lined stainless steel. The probe
must be heated to prevent moisture condensation. It must be
designed to allow calibration gas to enter the probe at or near the
sample point entry. Any portion of the probe that contacts the
stack gas must be heated to prevent moisture condensation. Figure
16-1 illustrates the probe used in lime kilns and other sources
where significant amounts of particulate matter are present. The
probe is designed with the deflector shield placed between the
sample and the gas inlet holes to reduce clogging of the filter and
possible adsorption of sample gas. As an alternative, the probe
described in section 6.1.1 of Method 16A having a nozzle directed
away from the gas stream may be used at sources having significant
amounts of particulate matter.
6.1.2 Particulate Filter. 50-mm Teflon filter holder and a 1- to
2-micron porosity Teflon filter (available through Savillex
Corporation, 5325 Highway 101, Minnetonka, Minnesota 55343). The
filter holder must be maintained in a hot box at a temperature of
at least 120 °C (248 °F).
6.1.3 SO2 Scrubber. Three 300-ml Teflon segmented impingers
connected in series with flexible, thick-walled, Teflon tubing.
(Impinger parts and tubing available through Savillex.) The first
two impingers contain 100 ml of citrate buffer and the third
impinger is initially dry. The tip of the tube inserted into the
solution should be constricted to less than 3 mm ( 1/8 in.) ID and
should be immersed to a depth of at least 5 cm (2 in.). Immerse the
impingers in an ice water bath and maintain near 0 °C (32 °F). The
scrubber solution will normally last for a 3-hour run before
needing replacement. This will depend upon the effects of moisture
and particulate matter on the solution strength and pH. Connections
between the probe, particulate filter, and SO2 scrubber must be
made of Teflon and as short in length as possible. All portions of
the probe, particulate filter, and connections prior to the SO2
scrubber (or alternative point of moisture removal) must be
maintained at a temperature of at least 120 °C (248 °F).
6.1.4 Sample Line. Teflon, no greater than 1.3 cm ( 1/2 in.) ID.
Alternative materials, such as virgin Nylon, may be used provided
the line loss test is acceptable.
6.1.5 Sample Pump. The sample pump must be a leakless
Teflon-coated diaphragm type or equivalent.
6.2 Analysis. The following items are needed for sample
analysis:
6.2.1 Dilution System. Needed only for high sample
concentrations. The dilution system must be constructed such that
all sample contacts are made of Teflon, glass, or stainless
steel.
6.2.2 Gas Chromatograph. The gas chromatograph must have at
least the following components:
6.2.2.1 Oven. Capable of maintaining the separation column at
the proper operating temperature ±1 °C (2 °F).
6.2.2.2 Temperature Gauge. To monitor column oven, detector, and
exhaust temperature ±1 °C (2 °F).
6.2.2.3 Flow System. Gas metering system to measure sample,
fuel, combustion gas, and carrier gas flows.
6.2.2.4 Flame Photometric Detector.
6.2.2.4.1 Electrometer. Capable of full scale amplification of
linear ranges of 10−9 to 10−4 amperes full scale.
6.2.2.4.2 Power Supply. Capable of delivering up to 750
volts.
6.2.2.4.3 Recorder. Compatible with the output voltage range of
the electrometer.
6.2.2.4.4 Rotary Gas Valves. Multiport Teflon-lined valves
equipped with sample loop. Sample loop volumes must be chosen to
provide the needed analytical range. Teflon tubing and fittings
must be used throughout to present an inert surface for sample gas.
The gas chromatograph must be calibrated with the sample loop used
for sample analysis.
6.2.3 Gas Chromatogram Columns. The column system must be
demonstrated to be capable of resolving the four major reduced
sulfur compounds: H2S, MeSH, DMS, and DMDS. It must also
demonstrate freedom from known interferences. To demonstrate that
adequate resolution has been achieved, submit a chromatogram of a
calibration gas containing all four of the TRS compounds in the
concentration range of the applicable standard. Adequate resolution
will be defined as base line separation of adjacent peaks when the
amplifier attenuation is set so that the smaller peak is at least
50 percent of full scale. Baseline separation is defined as a
return to zero ±5 percent in the interval between peaks. Systems
not meeting this criteria may be considered alternate methods
subject to the approval of the Administrator.
6.3 Calibration. A calibration system, containing the following
components, is required (see Figure 16-2).
6.3.1 Tube Chamber. Chamber of glass or Teflon of sufficient
dimensions to house permeation tubes.
6.3.2 Flow System. To measure air flow over permeation tubes at
±2 percent. Flow over the permeation device may also be determined
using a soap bubble flowmeter.
6.3.3 Constant Temperature Bath. Device capable of maintaining
the permeation tubes at the calibration temperature within 0.1 °C
(0.2 °F).
6.3.4 Temperature Gauge. Thermometer or equivalent to monitor
bath temperature within 1 °C (2 °F).
7.0 Reagents and Standards
7.1 Fuel. Hydrogen (H2), prepurified grade or better.
7.2 Combustion Gas. Oxygen (O2) or air, research purity or
better.
7.3 Carrier Gas. Prepurified grade or better.
7.4 Diluent (if required). Air containing less than 50 ppb total
sulfur compounds and less than 10 ppmv each of moisture and total
hydrocarbons.
7.5 Calibration Gases
7.5.1 Permeation tubes, one each of H2S, MeSH, DMS, and DMDS,
gravimetrically calibrated and certified at some convenient
operating temperature. These tubes consist of hermetically sealed
FEP Teflon tubing in which a liquified gaseous substance is
enclosed. The enclosed gas permeates through the tubing wall at a
constant rate. When the temperature is constant, calibration gases
covering a wide range of known concentrations can be generated by
varying and accurately measuring the flow rate of diluent gas
passing over the tubes. These calibration gases are used to
calibrate the GC/FPD system and the dilution system.
7.5.2 Cylinder Gases. Cylinder gases may be used as alternatives
to permeation devices. The gases must be traceable to a primary
standard (such as permeation tubes) and not used beyond the
certification expiration date.
7.6 Citrate Buffer and Sample Line Loss Gas. Same as Method 15,
sections 7.6 and 7.7.
8.0 Sample Collection, Preservation, Storage, and Transport
Same as Method 15, section 8.0, except that the references to
the dilution system may not be applicable.
9.0 Quality Control
Section
Quality control measure
Effect
8.0
Sample line loss check
Ensures that uncorrected
negative bias introduced by sample loss is no greater than 20
percent, and provides for correction of bias of 20 percent or
less.
8.0
Calibration drift test
Ensures that bias introduced
by drift in the measurement system output during the run is no
greater than 5 percent.
10.0
Analytical calibration
Ensures precision of
analytical results within 5 percent.
10.0 Calibration and Standardization
Same as Method 15, section 10.0, with the following addition and
exceptions:
10.1 Use the four compounds that comprise TRS instead of the
three reduced sulfur compounds measured by Method 15.
10.2 Flow Meter. Calibration before each test run is
recommended, but not required; calibration following each test
series is mandatory. Calibrate each flow meter after each complete
test series with a wet-test meter. If the flow measuring device
differs from the wet-test meter by 5 percent or more, the completed
test runs must be voided. Alternatively, the flow data that yield
the lower flow measurement may be used. Flow over the permeation
device may also be determined using a soap bubble flowmeter.
11.0 Analytical Procedure
Sample collection and analysis are concurrent for this method
(see section 8.0).
12.0 Data Analysis and Calculations
12.1 Concentration of Reduced Sulfur Compounds. Calculate the
average concentration of each of the four analytes (i.e.,
DMDS, DMS, H2S, and MeSH) over the sample run (specified in section
8.2 of Method 15 as 16 injections).
Where: Si = Concentration of any reduced sulfur
compound from the i th sample injection, ppm. C = Average
concentration of any one of the reduced sulfur compounds for the
entire run, ppm. N = Number of injections in any run period.
12.2 TRS Concentration. Using Equation 16-2, calculate the TRS
concentration for each sample run.
12.3 Average TRS Concentration. Calculate the average TRS
concentration for all sample runs performed.
Where: Average TRS = Average total reduced
sulfur in ppm. TRSi = Total reduced sulfur in ppm as determined by
Equation 16-2. N = Number of samples. Bwo = Fraction of volume of
water vapor in the gas stream as determined by Method 4 -
Determination of Moisture in Stack Gases. 13.0 Method Performance
13.1 Analytical Range. The analytical range will vary with the
sample loop size. Typically, the analytical range may extend from
0.1 to 100 ppmv using 10- to 0.1-ml sample loop sizes. This
eliminates the need for sample dilution in most cases.
13.2 Sensitivity. Using the 10-ml sample size, the minimum
detectable concentration is approximately 50 ppb.
1. O'Keeffe, A.E., and G.C. Ortman. “Primary Standards for Trace
Gas Analysis.” Analytical Chemical Journal, 38,76. 1966.
2. Stevens, R.K., A.E. O'Keeffe, and G.C. Ortman. “Absolute
Calibration of a Flame Photometric Detector to Volatile Sulfur
Compounds at Sub-Part-Per-Million Levels.” Environmental Science
and Technology, 3:7. July 1969.
3. Mulik, J.D., R.K. Stevens, and R. Baumgardner. “An Analytical
System Designed to Measure Multiple Malodorous Compounds Related to
Kraft Mill Activities.” Presented at the 12th Conference on Methods
in Air Pollution and Industrial Hygiene Studies, University of
Southern California, Los Angeles, CA. April 6-8, 1971.
4. Devonald, R.H., R.S. Serenius, and A.D. McIntyre. “Evaluation
of the Flame Photometric Detector for Analysis of Sulfur
Compounds.” Pulp and Paper Magazine of Canada, 73,3. March
1972.
5. Grimley, K.W., W.S. Smith, and R.M. Martin. “The Use of a
Dynamic Dilution System in the Conditioning of Stack Gases for
Automated Analysis by a Mobile Sampling Van.” Presented at the 63rd
Annual APCA Meeting, St. Louis, MO. June 14-19, 1970.
6. General Reference. Standard Methods of Chemical Analysis,
Volumes III-A and III-B Instrumental Methods. Sixth Edition. Van
Nostrand Reinhold Co.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 16A -
Determination of Total Reduced Sulfur Emissions From Stationary
Sources (Impinger Technique) Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 6, and Method 16.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Total reduced
sulfur (TRS) including:
N/A
See section 13.1.
Dimethyl
disulfide [(CH3)2S2]
62-49-20
Dimethyl
sulfide [(CH3)2S]
75-18-3
Hydrogen
sulfide [H2S]
7783-06-4
Methyl
mercaptan [CH4S]
74-93-1
Reduced sulfur
(RS) including:
N/A
H2S
7783-06-4
Carbonyl
sulfide [COS]
463-58-1
Carbon
disulfide [CS2]
75-15-0
Reported as:
Sulfur dioxide (SO2)
7449-09-5
1.2 Applicability. This method is applicable for the
determination of TRS emissions from recovery boilers, lime kilns,
and smelt dissolving tanks at kraft pulp mills, reduced sulfur
compounds (H2S, carbonyl sulfide, and carbon disulfide) from sulfur
recovery units at onshore natural gas processing facilities, and
from other sources when specified in an applicable subpart of the
regulations. The flue gas must contain at least 1 percent oxygen
for complete oxidation of all TRS to SO2. Note: If sources other
than kraft pulp mills experience low oxygen levels in the
emissions, the method results may be biased low.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 An integrated gas sample is extracted from the stack. SO2 is
removed selectively from the sample using a citrate buffer
solution. TRS compounds are then thermally oxidized to SO2,
collected in hydrogen peroxide as sulfate, and analyzed by the
Method 6 barium-thorin titration procedure.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Reduced sulfur compounds other than those regulated by the
emission standards, if present, may be measured by this method.
Therefore, carbonyl sulfide, which is partially oxidized to SO2 and
may be present in a lime kiln exit stack, would be a positive
interferant.
4.2 Particulate matter from the lime kiln stack gas (primarily
calcium carbonate) can cause a negative bias if it is allowed to
enter the citrate scrubber; the particulate matter will cause the
pH to rise and H2S to be absorbed prior to oxidation. Furthermore,
if the calcium carbonate enters the hydrogen peroxide impingers,
the calcium will precipitate sulfate ion. Proper use of the
particulate filter described in section 6.1.3 will eliminate this
interference.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Corrosive reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water for at least 15 minutes. Remove
clothing under shower and decontaminate. Treat residual chemical
burns as thermal burns.
5.2.1 Hydrogen Peroxide (H2O2). Irritating to eyes, skin, nose,
and lungs.
5.2.2 Sodium Hydroxide (NaOH). Causes severe damage to eyes and
skin. Inhalation causes irritation to nose, throat, and lungs.
Reacts exothermically with limited amounts of water.
5.2.3 Sulfuric Acid (H2SO4). Rapidly destructive to body tissue.
Will cause third degree burns. Eye damage may result in blindness.
Inhalation may be fatal from spasm of the larynx, usually within 30
minutes. May cause lung tissue damage with edema. 3 mg/m 3 will
cause lung damage in uninitiated. 1 mg/m 3 for 8 hours will cause
lung damage or, in higher concentrations, death. Provide
ventilation to limit inhalation. Reacts violently with metals and
organics.
5.3 Hydrogen Sulfide (H2S). A flammable, poisonous gas with the
odor of rotten eggs. H2S is extremely hazardous and can cause
collapse, coma, and death within a few seconds of one or two
inhalations at sufficient concentrations. Low concentrations
irritate the mucous membranes and may cause nausea, dizziness, and
headache after exposure.
6.0 Equipment and Supplies
6.1 Sample Collection. The sampling train is shown in Figure
16A-1 and component parts are discussed below. Modifications to
this sampling train are acceptable provided the system performance
check is met (see section 8.5).
6.1.1 Probe. Teflon tubing, 6.4-mm ( 1/4-in.) diameter,
sequentially wrapped with heat-resistant fiber strips, a rubberized
heat tape (plug at one end), and heat-resistant adhesive tape. A
flexible thermocouple or other suitable temperature measuring
device should be placed between the Teflon tubing and the fiber
strips so that the temperature can be monitored to prevent
softening of the probe. The probe should be sheathed in stainless
steel to provide in-stack rigidity. A series of bored-out stainless
steel fittings placed at the front of the sheath will prevent
moisture and particulate from entering between the probe and
sheath. A 6.4-mm ( 1/4-in.) Teflon elbow (bored out) should be
attached to the inlet of the probe, and a 2.54 cm (1 in.) piece of
Teflon tubing should be attached at the open end of the elbow to
permit the opening of the probe to be turned away from the
particulate stream; this will reduce the amount of particulate
drawn into the sampling train. The probe is depicted in Figure
16A-2.
6.1.2 Probe Brush. Nylon bristle brush with handle inserted into
a 3.2-mm ( 1/8-in.) Teflon tubing. The Teflon tubing should be long
enough to pass the brush through the length of the probe.
6.1.3 Particulate Filter. 50-mm Teflon filter holder and a 1- to
2-µm porosity, Teflon filter (available through Savillex
Corporation, 5325 Highway 101, Minnetonka, Minnesota 55343). The
filter holder must be maintained in a hot box at a temperature
sufficient to prevent moisture condensation. A temperature of 121
°C (250 °F) was found to be sufficient when testing a lime kiln
under sub-freezing ambient conditions.
6.1.4 SO2 Scrubber. Three 300-ml Teflon segmented impingers
connected in series with flexible, thick-walled, Teflon tubing.
(Impinger parts and tubing available through Savillex.) The first
two impingers contain 100 ml of citrate buffer and the third
impinger is initially dry. The tip of the tube inserted into the
solution should be constricted to less than 3 mm ( 1/8-in.) ID and
should be immersed to a depth of at least 5 cm (2 in.).
6.1.5 Combustion Tube. Quartz glass tubing with an expanded
combustion chamber 2.54 cm (1 in.) in diameter and at least 30.5 cm
(12 in.) long. The tube ends should have an outside diameter of 0.6
cm ( 1/4 in.) and be at least 15.3 cm (6 in.) long. This length is
necessary to maintain the quartz-glass connector near ambient
temperature and thereby avoid leaks. Alternatively, the outlet may
be constructed with a 90-degree glass elbow and socket that would
fit directly onto the inlet of the first peroxide impinger.
6.1.6 Furnace. A furnace of sufficient size to enclose the
combustion chamber of the combustion tube with a temperature
regulator capable of maintaining the temperature at 800 ±100 °C
(1472 ±180 °F). The furnace operating temperature should be checked
with a thermocouple to ensure accuracy.
6.1.7 Peroxide Impingers, Stopcock Grease, Temperature Sensor,
Drying Tube, Valve, Pump, and Barometer. Same as Method 6, sections
6.1.1.2, 6.1.1.4, 6.1.1.5, 6.1.1.6, 6.1.1.7, 6.1.1.8, and 6.1.2,
respectively, except that the midget bubbler of Method 6, section
6.1.1.2 is not required.
6.1.8 Vacuum Gauge. At least 760 mm Hg (30 in. Hg) gauge.
6.1.9 Rate Meter. Rotameter, or equivalent, accurate to within 5
percent at the selected flow rate of approximately 2 liters/min
(4.2 ft 3/hr).
6.1.10 Volume Meter. Dry gas meter capable of measuring the
sample volume under the sampling conditions of 2 liters/min (4.2 ft
3/hr) with an accuracy of 2 percent.
6.2 Sample Recovery. Polyethylene Bottles, 250-ml (one per
sample).
6.3 Sample Preparation and Analysis. Same as Method 6, section
6.3, except a 10-ml buret with 0.05-ml graduations is required, and
the spectrophotometer is not needed.
7.0 Reagents and Standards Note:
Unless otherwise indicated, all reagents must conform to the
specifications established by the Committee on Analytical Reagents
of the American Chemical Society. When such specifications are not
available, the best available grade must be used.
7.1 Sample Collection. The following reagents are required for
sample analysis:
7.1.1 Water. Same as in Method 6, section 7.1.1.
7.1.2 Citrate Buffer. Dissolve 300 g of potassium citrate (or
284 g of sodium citrate) and 41 g of anhydrous citric acid in 1
liter of water (200 ml is needed per test). Adjust the pH to
between 5.4 and 5.6 with potassium citrate or citric acid, as
required.
7.1.3 Hydrogen Peroxide, 3 percent. Same as in Method 6, section
7.1.3 (40 ml is needed per sample).
7.1.4 Recovery Check Gas. Hydrogen sulfide (100 ppmv or less) in
nitrogen, stored in aluminum cylinders. Verify the concentration by
Method 11 or by gas chromatography where the instrument is
calibrated with an H2S permeation tube as described below. For
Method 11, the relative standard deviation should not exceed 5
percent on at least three 20-minute runs.
Note:
Alternatively, hydrogen sulfide recovery gas generated from a
permeation device gravimetrically calibrated and certified at some
convenient operating temperature may be used. The permeation rate
of the device must be such that at a dilution gas flow rate of 3
liters/min (6.4 ft 3/hr), an H2S concentration in the range of the
stack gas or within 20 percent of the standard can be
generated.
7.1.5 Combustion Gas. Gas containing less than 50 ppb reduced
sulfur compounds and less than 10 ppmv total hydrocarbons. The gas
may be generated from a clean-air system that purifies ambient air
and consists of the following components: Diaphragm pump, silica
gel drying tube, activated charcoal tube, and flow rate measuring
device. Flow from a compressed air cylinder is also acceptable.
7.2 Sample Recovery and Analysis. Same as Method 6, sections
7.2.1 and 7.3, respectively.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Preparation of Sampling Train.
8.1.1 For the SO2 scrubber, measure 100 ml of citrate buffer
into the first and second impingers; leave the third impinger
empty. Immerse the impingers in an ice bath, and locate them as
close as possible to the filter heat box. The connecting tubing
should be free of loops. Maintain the probe and filter temperatures
sufficiently high to prevent moisture condensation, and monitor
with a suitable temperature sensor.
8.1.2 For the Method 6 part of the train, measure 20 ml of 3
percent hydrogen peroxide into the first and second midget
impingers. Leave the third midget impinger empty, and place silica
gel in the fourth midget impinger. Alternatively, a silica gel
drying tube may be used in place of the fourth impinger. Maintain
the oxidation furnace at 800 ±100 °C (1472 ±180 °F). Place crushed
ice and water around all impingers.
8.2 Citrate Scrubber Conditioning Procedure. Condition the
citrate buffer scrubbing solution by pulling stack gas through the
Teflon impingers and bypassing all other sampling train components.
A purge rate of 2 liters/min for 10 minutes has been found to be
sufficient to obtain equilibrium. After the citrate scrubber has
been conditioned, assemble the sampling train, and conduct
(optional) a leak-check as described in Method 6, section 8.2.
8.3 Sample Collection. Same as in Method 6, section 8.3, except
the sampling rate is 2 liters/min (±10 percent) for 1 or 3 hours.
After the sample is collected, remove the probe from the stack, and
conduct (mandatory) a post-test leak-check as described in Method
6, section 8.2. The 15-minute purge of the train following
collection should not be performed. After each 3-hour test run (or
after three 1-hour samples), conduct one system performance check
(see section 8.5) to determine the reduced sulfur recovery
efficiency through the sampling train. After this system
performance check and before the next test run, rinse and brush the
probe with water, replace the filter, and change the citrate
scrubber (optional but recommended).
Note:
In Method 16, a test run is composed of 16 individual analyses
(injects) performed over a period of not less than 3 hours or more
than 6 hours. For Method 16A to be consistent with Method 16, the
following may be used to obtain a test run: (1) collect three
60-minute samples or (2) collect one 3-hour sample. (Three test
runs constitute a test.)
8.4 Sample Recovery. Disconnect the impingers. Quantitatively
transfer the contents of the midget impingers of the Method 6 part
of the train into a leak-free polyethylene bottle for shipment.
Rinse the three midget impingers and the connecting tubes with
water and add the washings to the same storage container. Mark the
fluid level. Seal and identify the sample container.
8.5 System Performance Check.
8.5.1 A system performance check is done (1) to validate the
sampling train components and procedure (prior to testing;
optional) and (2) to validate a test run (after a run). Perform a
check in the field prior to testing consisting of at least two
samples (optional), and perform an additional check after each 3
hour run or after three 1-hour samples (mandatory).
8.5.2 The checks involve sampling a known concentration of H2S
and comparing the analyzed concentration with the known
concentration. Mix the H2S recovery check gas (Section 7.1.4) and
combustion gas in a dilution system such as that shown in Figure
16A-3. Adjust the flow rates to generate an H2S concentration in
the range of the stack gas or within 20 percent of the applicable
standard and an oxygen concentration greater than 1 percent at a
total flow rate of at least 2.5 liters/min (5.3 ft 3/hr). Use
Equation 16A-3 to calculate the concentration of recovery gas
generated. Calibrate the flow rate from both sources with a soap
bubble flow meter so that the diluted concentration of H2S can be
accurately calculated.
8.5.3 Collect 30-minute samples, and analyze in the same manner
as the emission samples. Collect the sample through the probe of
the sampling train using a manifold or some other suitable device
that will ensure extraction of a representative sample.
8.5.4 The recovery check must be performed in the field prior to
replacing the SO2 scrubber and particulate filter and before the
probe is cleaned. Use Equation 16A-4 (see section 12.5) to
calculate the recovery efficiency. Report the recovery efficiency
with the emission data; do not correct the emission data for the
recovery efficiency. A sample recovery of 100 ±20 percent must be
obtained for the emission data to be valid. However, if the
recovery efficiency is not in the 100 ±20 percent range but the
results do not affect the compliance or noncompliance status of the
affected facility, the Administrator may decide to accept the
results of the compliance test.
9.0 Quality Control
Section
Quality control measure
Effect
8.5
System performance check
Ensure validity of sampling
train components and analytical procedure.
8.2, 10.0
Sampling equipment leak-check
and calibration
Ensure accurate measurement of
stack gas flow rate, sample volume.
10.0
Barium standard solution
standardization
Ensure precision of normality
determination.
11.1
Replicate titrations
Ensure precision of titration
determinations.
10.0 Calibration
Same as Method 6, section 10.0.
11.0 Analytical Procedure
11.1 Sample Loss Check and Sample Analysis. Same as Method 6,
sections 11.1 and 11.2, respectively, with the following exception:
for 1-hour sampling, take a 40-ml aliquot, add 160 ml of 100
percent isopropanol and four drops of thorin.
12.0 Data Analysis and Calculations
In the calculations, at least one extra decimal figure should be
retained beyond that of the acquired data. Figures should be
rounded off after final calculations.
12.1 Nomenclature.
CTRS = Concentration of TRS as SO2, dry basis corrected to standard
conditions, ppmv. CRG(act) = Actual concentration of recovery check
gas (after dilution), ppm. CRG(m) = Measured concentration of
recovery check gas generated, ppm. CH2S = Verified concentration of
H2S recovery gas. N = Normality of barium perchlorate titrant,
milliequivalents/ml. Pbar = Barometric pressure at exit orifice of
the dry gas meter, mm Hg (in. Hg). Pstd = Standard absolute
pressure, 760 mm Hg (29.92 in. Hg). QH2S = Calibrated flow rate of
H2S recovery gas, liters/min. QCG = Calibrated flow rate of
combustion gas, liters/min. R = Recovery efficiency for the system
performance check, percent. Tm = Average dry gas meter absolute
temperature, °K (°R). Tstd = Standard absolute temperature, 293 °K
(528 °R). Va = Volume of sample aliquot titrated, ml. Vm = Dry gas
volume as measured by the dry gas meter, liters (dcf). Vm(std) =
Dry gas volume measured by the dry gas meter, corrected to standard
conditions, liters (dscf). Vsoln = Total volume of solution in
which the sulfur dioxide sample is contained, 100 ml. Vt = Volume
of barium perchlorate titrant used for the sample, ml (average of
replicate titrations). Vtb = Volume of barium perchlorate titrant
used for the blank, ml. Y = Dry gas meter calibration factor. 32.03
= Equivalent weight of sulfur dioxide, mg/meq.
12.2 Dry Sample Gas Volume, Corrected to Standard
Conditions.
Where: K1 = 0.3855 °K/mm Hg for metric units, =
17.65 °R/in. Hg for English units.
12.3 Concentration of TRS as ppm SO2.
Where:
12.4 Concentration of Recovery Gas Generated in the System
Performance Check.
12.5 Recovery Efficiency for the System Performance Check.
13.0 Method Performance
13.1 Analytical Range. The lower detectable limit is 0.1 ppmv
SO2 when sampling at 2 liters/min (4.2 ft 3/hr) for 3 hours or 0.3
ppmv when sampling at 2 liters/min (4.2 ft 3/hr) for 1 hour. The
upper concentration limit of the method exceeds the TRS levels
generally encountered at kraft pulp mills.
13.2 Precision. Relative standard deviations of 2.0 and 2.6
percent were obtained when sampling a recovery boiler for 1 and 3
hours, respectively.
13.3 Bias.
13.3.1 No bias was found in Method 16A relative to Method 16 in
a separate study at a recovery boiler.
13.3.2 Comparison of Method 16A with Method 16 at a lime kiln
indicated that there was no bias in Method 16A. However,
instability of the source emissions adversely affected the
comparison. The precision of Method 16A at the lime kiln was
similar to that obtained at the recovery boiler (Section
13.2.1).
13.3.3 Relative standard deviations of 2.7 and 7.7 percent have
been obtained for system performance checks.
As an alternative to the procedures specified in section 7.1.4,
the following procedure may be used to verify the H2S concentration
of the recovery check gas.
16.1 Summary. The H2S is collected from the calibration gas
cylinder and is absorbed in zinc acetate solution to form zinc
sulfide. The latter compound is then measured iodometrically.
16.2 Range. The procedure has been examined in the range of 5 to
1500 ppmv.
16.3 Interferences. There are no known interferences to this
procedure when used to analyze cylinder gases containing H2S in
nitrogen.
16.4 Precision and Bias. Laboratory tests have shown a relative
standard deviation of less than 3 percent. The procedure showed no
bias when compared to a gas chromatographic method that used
gravimetrically certified permeation tubes for calibration.
16.5 Equipment and Supplies.
16.5.1 Sampling Apparatus. The sampling train is shown in Figure
16A-4. Its component parts are discussed in sections 16.5.1.1
through 16.5.2.
16.5.1.1 Sampling Line. Teflon tubing ( 1/4-in.) to connect the
cylinder regulator to the sampling valve.
16.5.1.2 Needle Valve. Stainless steel or Teflon needle valve to
control the flow rate of gases to the impingers.
16.5.1.3 Impingers. Three impingers of approximately 100-ml
capacity, constructed to permit the addition of reagents through
the gas inlet stem. The impingers shall be connected in series with
leak-free glass or Teflon connectors. The impinger bottoms have a
standard 24/25 ground-glass fitting. The stems are from standard
6.4-mm ( 1/4-in.) ball joint midget impingers, custom lengthened by
about 1 in. When fitted together, the stem end should be
approximately 1.27 cm ( 1/2 in.) from the bottom (Southern
Scientific, Inc., Micanopy, Florida: Set Number S6962-048). The
third in-line impinger acts as a drop-out bottle.
16.5.1.4 Drying Tube, Rate Meter, and Barometer. Same as Method
11, sections 6.1.5, 6.1.8, and 6.1.10, respectively.
16.5.1.5 Cylinder Gas Regulator. Stainless steel, to reduce the
pressure of the gas stream entering the Teflon sampling line to a
safe level.
16.5.1.6 Soap Bubble Meter. Calibrated for 100 and 500 ml, or
two separate bubble meters.
16.5.1.7 Critical Orifice. For volume and rate measurements. The
critical orifice may be fabricated according to section 16.7.3 and
must be calibrated as specified in section 16.12.4.
16.5.1.8 Graduated Cylinder. 50-ml size.
16.5.1.9 Volumetric Flask. 1-liter size.
16.5.1.10 Volumetric Pipette. 15-ml size.
16.5.1.11 Vacuum Gauge. Minimum 20 in. Hg capacity.
16.5.1.12 Stopwatch.
16.5.2 Sample Recovery and Analysis.
16.5.2.1 Erlenmeyer Flasks. 125- and 250-ml sizes.
16.5.2.2 Pipettes. 2-, 10-, 20-, and 100-ml volumetric.
16.5.2.3 Burette. 50-ml size.
16.5.2.4 Volumetric Flask. 1-liter size.
16.5.2.5 Graduated Cylinder. 50-ml size.
16.5.2.6 Wash Bottle.
16.5.2.7 Stirring Plate and Bars.
16.6 Reagents and Standards. Unless otherwise indicated, all
reagents must conform to the specifications established by the
Committee on Analytical Reagents of the American Chemical Society,
where such specifications are available. Otherwise, use the best
available grade.
16.6.1 Water. Same as Method 11, section 7.1.3.
16.6.2 Zinc Acetate Absorbing Solution. Dissolve 20 g zinc
acetate in water, and dilute to 1 liter.
16.6.3 Potassium Bi-iodate [KH(IO3)2] Solution, Standard 0.100
N. Dissolve 3.249 g anhydrous KH(IO3)2 in water, and dilute to 1
liter.
16.6.4 Sodium Thiosulfate (Na2S2O3) Solution, Standard 0.1 N.
Same as Method 11, section 7.3.2. Standardize according to section
16.12.2.
16.6.5 Na2S2O3 Solution, Standard 0.01 N. Pipette 100.0 ml of
0.1 N Na2S2O3 solution into a 1-liter volumetric flask, and dilute
to the mark with water.
16.6.6 Iodine Solution, 0.1 N. Same as Method 11, section
7.2.3.
16.6.7 Standard Iodine Solution, 0.01 N. Same as in Method 11,
section 7.2.4. Standardize according to section 16.12.3.
16.6.8 Hydrochloric Acid (HCl) Solution, 10 Percent by Weight.
Add 230 ml concentrated HCl (specific gravity 1.19) to 770 ml
water.
16.6.9 Starch Indicator Solution. To 5 g starch (potato,
arrowroot, or soluble), add a little cold water, and grind in a
mortar to a thin paste. Pour into 1 liter of boiling water, stir,
and let settle overnight. Use the clear supernatant. Preserve with
1.25 g salicylic acid, 4 g zinc chloride, or a combination of 4 g
sodium propionate and 2 g sodium azide per liter of starch
solution. Some commercial starch substitutes are satisfactory.
16.7 Pre-test Procedures.
16.7.1 Selection of Gas Sample Volumes. This procedure has been
validated for estimating the volume of cylinder gas sample needed
when the H2S concentration is in the range of 5 to 1500 ppmv. The
sample volume ranges were selected in order to ensure a 35 to 60
percent consumption of the 20 ml of 0.01 N iodine (thus ensuring a
0.01 N Na2S2O3 titer of approximately 7 to 12 ml). The sample
volumes for various H2S concentrations can be estimated by dividing
the approximate ppm-liters desired for a given concentration range
by the H2S concentration stated by the manufacturer. For example,
for analyzing a cylinder gas containing approximately 10 ppmv H2S,
the optimum sample volume is 65 liters (650 ppm-liters/10 ppmv).
For analyzing a cylinder gas containing approximately 1000 ppmv
H2S, the optimum sample volume is 1 liter (1000 ppm-liters/1000
ppmv).
Approximate cylinder gas H2S
concentration (ppmv)
Approximate
ppm-liters
desired
5 to <30
650
30 to <500
800
500 to
<1500
1000
16.7.2 Critical Orifice Flow Rate Selection. The following table
shows the ranges of sample flow rates that are desirable in order
to ensure capture of H2S in the impinger solution. Slight
deviations from these ranges will not have an impact on measured
concentrations.
Cylinder gas H2S
concentration (ppmv)
Critical
orifice
flow rate
(ml/min)
5 to 50 ppmv
1500 ±500
50 to 250
ppmv
500 ±250
250 to <1000
ppmv
200 ±50
>1000 ppmv
75 ±25
16.7.3 Critical Orifice Fabrication. Critical orifice of desired
flow rates may be fabricated by selecting an orifice tube of
desired length and connecting 1/16-in. × 1/4-in. (0.16 cm × 0.64
cm) reducing fittings to both ends. The inside diameters and
lengths of orifice tubes needed to obtain specific flow rates are
shown below.
Tube
(in. OD)
Tube
(in. ID)
Length
(in.)
Flowrate
(ml/min)
Altech
Catalog No.
1/16
0.007
1.2
85
301430
1/16
0.01
3.2
215
300530
1/16
0.01
1.2
350
300530
1/16
0.02
1.2
1400
300230
16.7.4 Determination of Critical Orifice Approximate Flow Rate.
Connect the critical orifice to the sampling system as shown in
Figure 16A-4 but without the H2S cylinder. Connect a rotameter in
the line to the first impinger. Turn on the pump, and adjust the
valve to give a reading of about half atmospheric pressure. Observe
the rotameter reading. Slowly increase the vacuum until a stable
flow rate is reached, and record this as the critical vacuum. The
measured flow rate indicates the expected critical flow rate of the
orifice. If this flow rate is in the range shown in section 16.7.2,
proceed with the critical orifice calibration according to section
16.12.4.
16.7.5 Determination of Approximate Sampling Time. Determine the
approximate sampling time for a cylinder of known concentration.
Use the optimum sample volume obtained in section 16.7.1.
16.8 Sample Collection.
16.8.1 Connect the Teflon tubing, Teflon tee, and rotameter to
the flow control needle valve as shown in Figure 16A-4. Vent the
rotameter to an exhaust hood. Plug the open end of the tee. Five to
10 minutes prior to sampling, open the cylinder valve while keeping
the flow control needle valve closed. Adjust the delivery pressure
to 20 psi. Open the needle valve slowly until the rotameter shows a
flow rate approximately 50 to 100 ml above the flow rate of the
critical orifice being used in the system.
16.8.2 Place 50 ml of zinc acetate solution in two of the
impingers, connect them and the empty third impinger (dropout
bottle) and the rest of the equipment as shown in Figure 16A-4.
Make sure the ground-glass fittings are tight. The impingers can be
easily stabilized by using a small cardboard box in which three
holes have been cut, to act as a holder. Connect the Teflon sample
line to the first impinger. Cover the impingers with a dark cloth
or piece of plastic to protect the absorbing solution from light
during sampling.
16.8.3 Record the temperature and barometric pressure. Note the
gas flow rate through the rotameter. Open the closed end of the
tee. Connect the sampling tube to the tee, ensuring a tight
connection. Start the sampling pump and stopwatch simultaneously.
Note the decrease in flow rate through the excess flow rotameter.
This decrease should equal the known flow rate of the critical
orifice being used. Continue sampling for the period determined in
section 16.7.5.
16.8.4 When sampling is complete, turn off the pump and
stopwatch. Disconnect the sampling line from the tee and plug it.
Close the needle valve followed by the cylinder valve. Record the
sampling time.
16.9 Blank Analysis. While the sample is being collected, run a
blank as follows: To a 250-ml Erlenmeyer flask, add 100 ml of zinc
acetate solution, 20.0 ml of 0.01 N iodine solution, and 2 ml HCl
solution. Titrate, while stirring, with 0.01 N Na2S2O3 until the
solution is light yellow. Add starch, and continue titrating until
the blue color disappears. Analyze a blank with each sample, as the
blank titer has been observed to change over the course of a
day.
Note:
Iodine titration of zinc acetate solutions is difficult to
perform because the solution turns slightly white in color near the
end point, and the disappearance of the blue color is hard to
recognize. In addition, a blue color may reappear in the solution
about 30 to 45 seconds after the titration endpoint is reached.
This should not be taken to mean the original endpoint was in
error. It is recommended that persons conducting this test perform
several titrations to be able to correctly identify the endpoint.
The importance of this should be recognized because the results of
this analytical procedure are extremely sensitive to errors in
titration.
16.10 Sample Analysis. Sample treatment is similar to the blank
treatment. Before detaching the stems from the bottoms of the
impingers, add 20.0 ml of 0.01 N iodine solution through the stems
of the impingers holding the zinc acetate solution, dividing it
between the two (add about 15 ml to the first impinger and the rest
to the second). Add 2 ml HCl solution through the stems, dividing
it as with the iodine. Disconnect the sampling line, and store the
impingers for 30 minutes. At the end of 30 minutes, rinse the
impinger stems into the impinger bottoms. Titrate the impinger
contents with 0.01 N Na2S2O3. Do not transfer the contents of the
impinger to a flask because this may result in a loss of iodine and
cause a positive bias.
16.11 Post-test Orifice Calibration. Conduct a post-test
critical orifice calibration run using the calibration procedures
outlined in section 16.12.4. If the Qstd obtained before and after
the test differs by more than 5 percent, void the sample; if not,
proceed to perform the calculations.
16.12 Calibrations and Standardizations.
16.12.1 Rotameter and Barometer. Same as Method 11, sections
10.1.3 and 10.1.4.
16.12.2 Na2S2O3 Solution, 0.1 N. Standardize the 0.1 N Na2S2O3
solution as follows: To 80 ml water, stirring constantly, add 1 ml
concentrated H2SO4, 10.0 ml of 0.100 N KH(IO3)2 and 1 g potassium
iodide. Titrate immediately with 0.1 N Na2S2O3 until the solution
is light yellow. Add 3 ml starch solution, and titrate until the
blue color just disappears. Repeat the titration until replicate
analyses agree within 0.05 ml. Take the average volume of Na2S2O3
consumed to calculate the normality to three decimal figures using
Equation 16A-5.
16.12.3 Iodine Solution, 0.01 N. Standardize the 0.01 N iodine
solution as follows: Pipet 20.0 ml of 0.01 N iodine solution into a
125-ml Erlenmeyer flask. Titrate with standard 0.01 N Na2S2O3
solution until the solution is light yellow. Add 3 ml starch
solution, and continue titrating until the blue color just
disappears. If the normality of the iodine tested is not 0.010, add
a few ml of 0.1 N iodine solution if it is low, or a few ml of
water if it is high, and standardize again. Repeat the titration
until replicate values agree within 0.05 ml. Take the average
volume to calculate the normality to three decimal figures using
Equation 16A-6.
16.12.4 Critical Orifice. Calibrate the critical orifice using
the sampling train shown in Figure 16A-4 but without the H2S
cylinder and vent rotameter. Connect the soap bubble meter to the
Teflon line that is connected to the first impinger. Turn on the
pump, and adjust the needle valve until the vacuum is higher than
the critical vacuum determined in section 16.7.4. Record the time
required for gas flow to equal the soap bubble meter volume (use
the 100-ml soap bubble meter for gas flow rates below 100 ml/min,
otherwise use the 500-ml soap bubble meter). Make three runs, and
record the data listed in Table 16A-1. Use these data to calculate
the volumetric flow rate of the orifice.
16.13 Calculations.
16.13.1 Nomenclature.
Bwa = Fraction of water vapor in ambient air during orifice
calibration. CH2S = H2S concentration in cylinder gas, ppmv.
Ma = Molecular weight of ambient air saturated
at impinger temperature, g/g-mole. Ms = Molecular weight of sample
gas (nitrogen) saturated at impinger temperature, g/g-mole. Note:
(For tests carried out in a laboratory where the impinger
temperature is 25 °C, Ma = 28.5 g/g-mole and Ms = 27.7
g/g-mole.)
NI = Normality of standard iodine solution (0.01 N), g-eq/liter. NT
= Normality of standard Na2S2O3 solution (0.01 N), g-eq/liter. Pbar
= Barometric pressure, mm Hg. Pstd = Standard absolute pressure,
760 mm Hg. Qstd = Average volumetric flow rate through critical
orifice, liters/min. Tamb = Absolute ambient temperature, °K. Tstd
= Standard absolute temperature, 293 °K. θs = Sampling time, min.
θsb = Time for soap bubble meter flow rate measurement, min.
Vm(std) = Sample gas volume measured by the critical orifice,
corrected to standard conditions, liters. Vsb = Volume of gas as
measured by the soap bubble meter, ml. Vsb(std) = Volume of gas as
measured by the soap bubble meter, corrected to standard
conditions, liters. VI = Volume of standard iodine solution (0.01
N) used, ml. VT = Volume of standard Na2S2O3 solution (0.01 N)
used, ml. VTB = Volume of standard Na2S2O3 solution (0.01 N) used
for the blank, ml.
16.13.2 Normality of Standard Na2S2O3 Solution (0.1 N).
16.13.3 Normality of Standard Iodine Solution (0.01 N).
16.13.4 Sample Gas Volume.
16.13.5 Concentration of H2S in the Gas Cylinder.
17.0 References
1. American Public Health Association, American Water Works
Association, and Water Pollution Control Federation. Standard
Methods for the Examination of Water and Wastewater. Washington,
DC. American Public Health Association. 1975. pp. 316-317.
2. American Society for Testing and Materials. Annual Book of
ASTM Standards. Part 31: Water, Atmospheric Analysis. Philadelphia,
PA. 1974. pp. 40-42.
3. Blosser, R.O. A Study of TRS Measurement Methods. National
Council of the Paper Industry for Air and Stream Improvement, Inc.,
New York, NY. Technical Bulletin No. 434. May 1984. 14 pp.
4. Blosser, R.O., H.S. Oglesby, and A.K. Jain. A Study of
Alternate SO2 Scrubber Designs Used for TRS Monitoring. A Special
Report by the National Council of the Paper Industry for Air and
Stream Improvement, Inc., New York, NY. July 1977.
5. Curtis, F., and G.D. McAlister. Development and Evaluation of
an Oxidation/Method 6 TRS Emission Sampling Procedure. Emission
Measurement Branch, Emission Standards and Engineering Division,
U.S. Environmental Protection Agency, Research Triangle Park, NC
27711. February 1980.
6. Gellman, I. A Laboratory and Field Study of Reduced Sulfur
Sampling and Monitoring Systems. National Council of the Paper
Industry for Air and Stream Improvement, Inc., New York, NY.
Atmospheric Quality Improvement Technical Bulletin No. 81. October
1975.
7. Margeson, J.H., J.E. Knoll, and M.R. Midgett. A Manual Method
for TRS Determination. Source Branch, Quality Assurance Division,
U.S. Environmental Protection Agency, Research Triangle Park, NC
27711.
8. National Council of the Paper Industry for Air and Stream
Improvement. An Investigation of H2S and SO2. Calibration Cylinder
Gas Stability and Their Standardization Using Wet Chemical
Techniques. Special Report 76-06. New York, NY. August 1976.
9. National Council of the Paper Industry for Air and Stream
Improvement. Wet Chemical Method for Determining the H2S
Concentration of Calibration Cylinder Gases. Technical Bulletin
Number 450. New York, NY. January 1985. 23 pp.
10. National Council of the Paper Industry for Air and Stream
Improvement. Modified Wet Chemical Method for Determining the H2S
Concentration of Calibration Cylinder Gases. Draft Report. New
York, NY. March 1987. 29 pp.
18.0 Tables, Diagrams, Flowcharts, and Validation Data Date Critical
orifice ID Soap bubble meter volume, Vsb__ liters Time, θsb Run no.
1 __ min __ sec Run no. 2 __ min __ sec Run no. 3 __ min __ sec
Average __ min __ sec Covert the seconds to fraction of minute:
Time=__ min + __ Sec/60=__ min Barometric pressure, Pbar=__ mm Hg
Ambient temperature, t amb = 273 + __ °C=__ °K=__ mm Hg. (This
should be approximately 0.4 times barometric pressure.) Pump
vacuum, Table 16A-1. Critical Orifice
Calibration Data Method 16B - Determination of Total Reduced Sulfur
Emissions From Stationary Sources Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a knowledge of at least the following additional
test methods: Method 6C, Method 16, and Method 16A.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Total reduced
sulfur (TRS) including:
N/A
Dimethyl
disulfide (DMDS), [(CH3)2S2]
62-49-20
Dimethyl
sulfide (DMS), [(CH3)2S]
75-18-3
Hydrogen
sulfide (H2S)
7783-06-4
Methyl
mercaptan (MeSH), [CH4S]
74-93-1
Reported as:
Sulfur dioxide (SO2)
7449-09-5
1.2 Applicability. This method is applicable for determining TRS
emissions from recovery furnaces (boilers), lime kilns, and smelt
dissolving tanks at kraft pulp mills, and from other sources when
specified in an applicable subpart of the regulations. The flue gas
must contain at least 1 percent oxygen for complete oxidation of
all TRS to SO2.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A gas sample is extracted from the stack. The SO2 is removed
selectively from the sample using a citrate buffer solution. The
TRS compounds are then thermally oxidized to SO2 and analyzed as
SO2 by gas chromatography (GC) using flame photometric detection
(FPD).
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Reduced sulfur compounds other than those regulated by the
emission standards, if present, may be measured by this method.
Therefore, carbonyl sulfide, which is partially oxidized to SO2 and
may be present in a lime kiln exit stack, would be a positive
interferant.
4.2 Particulate matter from the lime kiln stack gas (primarily
calcium carbonate) can cause a negative bias if it is allowed to
enter the citrate scrubber; the particulate matter will cause the
pH to rise and H2S to be absorbed before oxidation. Proper use of
the particulate filter, described in section 6.1.3 of Method 16A,
will eliminate this interference.
4.3 Carbon monoxide (CO) and carbon dioxide (CO2) have
substantial desensitizing effects on the FPD even after dilution.
Acceptable systems must demonstrate that they have eliminated this
interference by some procedure such as eluting these compounds
before the SO2. Compliance with this requirement can be
demonstrated by submitting chromatograms of calibration gases with
and without CO2 in diluent gas. The CO2 level should be
approximately 10 percent for the case with CO2 present. The two
chromatograms should show agreement within the precision limits of
section 13.0.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Hydrogen Sulfide (H2S). A flammable, poisonous gas with the
odor of rotten eggs. H2S is extremely hazardous and can cause
collapse, coma, and death within a few seconds of one or two
inhalations at sufficient concentrations. Low concentrations
irritate the mucous membranes and may cause nausea, dizziness, and
headache after exposure.
6.0 Equipment and Supplies
6.1 Sample Collection. The sampling train is shown in Figure
16B-1. Modifications to the apparatus are accepted provided the
system performance check in section 8.3.1 is met.
6.1.1 Probe, Probe Brush, Particulate Filter, SO2 Scrubber,
Combustion Tube, and Furnace. Same as in Method 16A, sections 6.1.1
to 6.1.6.
6.1.2 Sampling Pump. Leakless Teflon-coated diaphragm type or
equivalent.
6.2 Analysis.
6.2.1 Dilution System (optional), Gas Chromatograph, Oven,
Temperature Gauges, Flow System, Flame Photometric Detector,
Electrometer, Power Supply, Recorder, Calibration System, Tube
Chamber, Flow System, and Constant Temperature Bath. Same as in
Method 16, sections 6.2.1, 6.2.2, and 6.3.
6.2.2 Gas Chromatograph Columns. Same as in Method 16, section
6.2.3. Other columns with demonstrated ability to resolve SO2 and
be free from known interferences are acceptable alternatives.
Single column systems such as a 7-ft Carbsorb B HT 100 column have
been found satisfactory in resolving SO2 from CO2.
7.0 Reagents and Standards
Same as in Method 16, section 7.0, except for the following:
7.1 Calibration Gas. SO2 permeation tube gravimetrically
calibrated and certified at some convenient operating temperature.
These tubes consist of hermetically sealed FEP Teflon tubing in
which a liquefied gaseous substance is enclosed. The enclosed gas
permeates through the tubing wall at a constant rate. When the
temperature is constant, calibration gases covering a wide range of
known concentrations can be generated by varying and accurately
measuring the flow rate of diluent gas passing over the tubes. In
place of SO2 permeation tubes, cylinder gases containing SO2 in
nitrogen may be used for calibration. The cylinder gas
concentration must be verified according to section 8.2.1 of Method
6C. The calibration gas is used to calibrate the GC/FPD system and
the dilution system.
7.2 Recovery Check Gas.
7.2.1 Hydrogen sulfide [100 parts per million by volume (ppmv)
or less] in nitrogen, stored in aluminum cylinders. Verify the
concentration by Method 11, the procedure discussed in section 16.0
of Method 16A, or gas chromatography where the instrument is
calibrated with an H2S permeation tube as described below. For the
wet-chemical methods, the standard deviation should not exceed 5
percent on at least three 20-minute runs.
7.2.2 Hydrogen sulfide recovery gas generated from a permeation
device gravimetrically calibrated and certified at some convenient
operation temperature may be used. The permeation rate of the
device must be such that at a dilution gas flow rate of 3
liters/min (64 ft 3/hr), an H2S concentration in the range of the
stack gas or within 20 percent of the emission standard can be
generated.
7.3 Combustion Gas. Gas containing less than 50 ppbv reduced
sulfur compounds and less than 10 ppmv total hydrocarbons. The gas
may be generated from a clean-air system that purifies ambient air
and consists of the following components: diaphragm pump, silica
gel drying tube, activated charcoal tube, and flow rate measuring
device. Gas from a compressed air cylinder is also acceptable.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Pretest Procedures. Same as in Method 15, section 8.1.
8.2 Sample Collection. Before any source sampling is performed,
conduct a system performance check as detailed in section 8.3.1 to
validate the sampling train components and procedures. Although
this test is optional, it would significantly reduce the
possibility of rejecting tests as a result of failing the post-test
performance check. At the completion of the pretest system
performance check, insert the sampling probe into the test port
making certain that no dilution air enters the stack though the
port. Condition the entire system with sample for a minimum of 15
minutes before beginning analysis. If the sample is diluted,
determine the dilution factor as in section 10.4 of Method 15.
8.3. Post-Test Procedures
8.3.1 System Performance Check. Same as in Method 16A, section
8.5. A sufficient number of sample injections should be made so
that the precision requirements of section 13.2 are satisfied.
8.3.2 Determination of Calibration Drift. Same as in Method 15,
section 8.3.2.
9.0 Quality Control
Section
Quality control measure
Effect
8.2, 8.3
System performance check
Ensure validity of sampling
train components and analytical procedure.
8.1
Sampling equipment leak-check
and calibration
Ensure accurate measurement of
stack gas flow rate, sample volume.
10.0
Analytical calibration
Ensure precision of analytical
results within 5 percent.
10.0 Calibration
Same as in Method 16, section 10, except SO2 is used instead of
H2S.
11.0 Analytical Procedure
11.1 Analysis. Inject aliquots of the sample into the GC/FPD
analyzer for analysis. Determine the concentration of SO2 directly
from the calibration curves or from the equation for the
least-squares line.
11.2 Perform analysis of a minimum of three aliquots or one
every 15 minutes, whichever is greater, spaced evenly over the test
period.
12.0 Data Analysis and Calculations
12.1 Nomenclature. CSO2 = Sulfur dioxide concentration, ppmv. CTRS
= Total reduced sulfur concentration as determined by Equation
16B-1, ppmv. d = Dilution factor, dimensionless. N = Number of
samples.
12.2 SO2 Concentration. Determine the concentration of SO2,
CSO2, directly from the calibration curves. Alternatively, the
concentration may be calculated using the equation for the
least-squares line.
12.3 TRS Concentration.
12.4 Average TRS Concentration
13.0 Method Performance.
13.1 Range and Sensitivity. Coupled with a GC using a 1-ml
sample size, the maximum limit of the FPD for SO2 is approximately
10 ppmv. This limit is extended by diluting the sample gas before
analysis or by reducing the sample aliquot size. For sources with
emission levels between 10 and 100 ppm, the measuring range can be
best extended by reducing the sample size.
13.2 GC/FPD Calibration and Precision. A series of three
consecutive injections of the sample calibration gas, at any
dilution, must produce results which do not vary by more than 5
percent from the mean of the three injections.
13.3 Calibration Drift. The calibration drift determined from
the mean of the three injections made at the beginning and end of
any run or series of runs within a 24-hour period must not exceed 5
percent.
13.4 System Calibration Accuracy. Losses through the sample
transport system must be measured and a correction factor developed
to adjust the calibration accuracy to 100 percent.
13.5 Field tests between this method and Method 16A showed an
average difference of less than 4.0 percent. This difference was
not determined to be significant.
2. National Council of the Paper Industry for Air and Stream
Improvement, Inc, A Study of TRS Measurement Methods. Technical
Bulletin No. 434. New York, NY. May 1984. 12p.
3. Margeson, J.H., J.E. Knoll, and M.R. Midgett. A Manual Method
for TRS Determination. Draft available from the authors. Source
Branch, Quality Assurance Division, U.S. Environmental Protection
Agency, Research Triangle Park, NC 27711.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 16C -
Determination of Total Reduced Sulfur Emissions From Stationary
Sources 1.0 Scope and Application What is Method 16C?
Method 16C is a procedure for measuring total reduced sulfur
(TRS) in stationary source emissions using a continuous
instrumental analyzer. Quality assurance and quality control
requirements are included to assure that you, the tester, collect
data of known quality. You must document your adherence to these
specific requirements for equipment, supplies, sample collection
and analysis, calculations, and data analysis. This method does not
completely describe all equipment, supplies, and sampling and
analytical procedures you will need but refers to other methods for
some of the details. Therefore, to obtain reliable results, you
should also have a thorough knowledge of these additional test
methods which are found in appendix A to this part:
(a) Method 6C - Determination of Sulfur Dioxide Emissions from
Stationary Sources (Instrumental Analyzer Procedure)
(b) Method 7E - Determination of Nitrogen Oxides Emissions from
Stationary Sources (Instrumental Analyzer Procedure)
(c) Method 16A - Determination of Total Reduced Sulfur Emissions
from Stationary Sources (Impinger Technique)
1.1 Analytes. What does Method 16C determine?
Analyte
CAS No.
Total reduced
sulfur including:
N/A
Dimethyl
disulfide (DMDS), [(CH3)2S2]
62-49-20
Dimethyl
sulfide (DMS), [(CH3)2S]
75-18-3
Hydrogen
sulfide (H2S)
7783-06-4
Methyl
mercaptan (MeSH), (CH4S)
74-93-1
Reported as:
Sulfur dioxide (SO2)
7449-09-5
1.2 Applicability. This method is applicable for determining TRS
emissions from recovery furnaces (boilers), lime kilns, and smelt
dissolving tanks at kraft pulp mills, and from other sources when
specified in an applicable subpart of the regulations.
1.3 Data Quality Objectives. Adherence to the requirements
described in Method 16C will enhance the quality of the data
obtained.
2.0 Summary of Method
2.1 An integrated gas sample is extracted from the stack. The
SO2 is removed selectively from the sample using a citrate buffer
solution. The TRS compounds are then thermally oxidized to SO2 and
determined as SO2 by an instrumental analyzer. This method is a
combination of the sampling procedures of Method 16A and the
analytical procedures of Method 6C (referenced in Method 7E), with
minor modifications to facilitate their use together.
3.0 Definitions
Analyzer calibration error, Calibration curve, Calibration
gas, Low-level gas, Mid-level gas, High-level gas, Calibration
drift, Calibration span, Data recorder, Direct calibration mode,
Gas analyzer, Interference check, Measurement system, Response
time, Run, System calibration mode, System performance check,
and Test are the same as used in Methods 16A and 6C.
4.0 Interferences
4.1 Reduced sulfur compounds other than those defined as TRS, if
present, may be measured by this method. Compounds like carbonyl
sulfide, which is partially oxidized to SO2 and may be present in a
lime kiln exit stack, would be a positive interferent.
Interferences may vary among instruments, and instrument-specific
interferences must be evaluated through the interference check.
4.2 Particulate matter from the lime kiln stack gas (primarily
calcium carbonate) can cause a negative bias if it is allowed to
enter the citrate scrubber; the particulate matter will cause the
pH to rise and H2S to be absorbed before oxidation. Proper use of
the particulate filter, described in section 6.1.3 of Method 16A,
will eliminate this interference.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user to establish appropriate safety and
health practices before performing this test method.
5.2 Hydrogen Sulfide. Hydrogen sulfide is a flammable, poisonous
gas with the odor of rotten eggs. Hydrogen sulfide is extremely
hazardous and can cause collapse, coma, and death within a few
seconds of one or two inhalations at sufficient concentrations. Low
concentrations irritate the mucous membranes and may cause nausea,
dizziness, and headache after exposure. It is the responsibility of
the user of this test method to establish appropriate safety and
health practices.
6.0 Equipment and Supplies What do I need for the measurement
system?
The measurement system is similar to those applicable components
in Methods 16A and 6C. Modifications to the apparatus are accepted
provided the performance criteria in section 13.0 are met.
6.1 Probe. Teflon tubing, 6.4-mm ( 1/4 in.) diameter,
sequentially wrapped with heat-resistant fiber strips, a rubberized
heat tape (plug at one end), and heat-resistant adhesive tape. A
flexible thermocouple or other suitable temperature measuring
device must be placed between the Teflon tubing and the fiber
strips so that the temperature can be monitored to prevent
softening of the probe. The probe must be sheathed in stainless
steel to provide in-stack rigidity. A series of bored-out stainless
steel fittings placed at the front of the sheath will prevent
moisture and particulate from entering between the probe and
sheath. A 6.4-mm ( 1/4 in.) Teflon elbow (bored out) must be
attached to the inlet of the probe, and a 2.54 cm (1 in.) piece of
Teflon tubing must be attached at the open end of the elbow to
permit the opening of the probe to be turned away from the
particulate stream; this will reduce the amount of particulate
drawn into the sampling train. The probe is depicted in Figure
16A-2 of Method 16A.
6.2 Probe Brush. Nylon bristle brush with handle inserted into a
3.2-mm ( 1/8 in.) Teflon tubing. The Teflon tubing should be long
enough to pass the brush through the length of the probe.
6.3 Particulate Filter. 50-mm Teflon filter holder and a 1- to
2-µm porosity, Teflon filter (may be available through Savillex
Corporation, 5325 Highway 101, Minnetonka, Minnesota 55343, or
other suppliers of filters). The filter holder must be maintained
in a hot box at a temperature sufficient to prevent moisture
condensation. A temperature of 121 °C (250 °F) was found to be
sufficient when testing a lime kiln under sub-freezing ambient
conditions.
6.4 SO2 Scrubber. Three 300-ml Teflon segmented impingers
connected in series with flexible, thick-walled, Teflon tubing.
(Impinger parts and tubing may be available through Savillex or
other suppliers.) The first two impingers contain 100 ml of citrate
buffer, and the third impinger is initially dry. The tip of the
tube inserted into the solution should be constricted to less than
3 mm ( 1/8 in.) ID and should be immersed to a depth of at least 5
cm (2 in.).
6.5 Combustion Tube. Quartz glass tubing with an expanded
combustion chamber 2.54 cm (1 in.) in diameter and at least 30.5 cm
(12 in.) long. The tube ends should have an outside diameter of 0.6
cm ( 1/4 in.) and be at least 15.3 cm (6 in.) long. This length is
necessary to maintain the quartz-glass connector near ambient
temperature and thereby avoid leaks. Alternative combustion tubes
are acceptable provided they are shown to combust TRS at
concentrations encountered during tests.
6.6 Furnace. A furnace of sufficient size to enclose the
combustion chamber of the combustion tube with a temperature
regulator capable of maintaining the temperature at 800 ±100 °C
(1472 ±180 °F). The furnace operating temperature should be checked
with a thermocouple to ensure accuracy.
6.7 Sampling Pump. A leak-free pump is required to pull the
sample gas through the system at a flow rate sufficient to minimize
the response time of the measurement system and must be constructed
of material that is non-reactive to the gas it contacts. For
dilution-type measurement systems, an eductor pump may be used to
create a vacuum that draws the sample through a critical orifice at
a constant rate.
6.8 Calibration Gas Manifold. The calibration gas manifold must
allow the introduction of calibration gases either directly to the
gas analyzer in direct calibration mode or into the measurement
system, at the probe, in system calibration mode, or both,
depending upon the type of system used. In system calibration mode,
the system must be able to flood the sampling probe and vent excess
gas. Alternatively, calibration gases may be introduced at the
calibration valve following the probe. Maintain a constant pressure
in the gas manifold. For in-stack dilution-type systems, a gas
dilution subsystem is required to transport large volumes of
purified air to the sample probe, and a probe controller is needed
to maintain the proper dilution ratio.
6.9 Sample Gas Manifold. The sample gas manifold diverts a
portion of the sample to the analyzer, delivering the remainder to
the by-pass discharge vent. The manifold should also be able to
introduce calibration gases directly to the analyzer. The manifold
must be made of material that is non-reactive to SO2 and be
configured to safely discharge the bypass gas.
6.10 SO2 Analyzer. You must use an instrument that uses an
ultraviolet, non-dispersive infrared, fluorescence, or other
detection principle to continuously measure SO2 in the gas stream
provided it meets the performance specifications in section
13.0.
6.11 Data Recording. A strip chart recorder, computerized data
acquisition system, digital recorder, or data logger for recording
measurement data must be used.
7.0 Reagents and Standards Note:
Unless otherwise indicated, all reagents must conform to the
specifications established by the Committee on Analytical Reagents
of the American Chemical Society. When such specifications are not
available, the best available grade must be used.
7.1 Water. Deionized distilled water must conform to ASTM
Specification D 1193-77 or 91 Type 3 (incorporated by reference -
see § 60.17). The KMnO4 test for oxidizable organic matter may be
omitted when high concentrations of organic matter are not expected
to be present.
7.2 Citrate Buffer. Dissolve 300 g of potassium citrate (or 284
g of sodium citrate) and 41 g of anhydrous citric acid in 1 liter
of water (200 ml is needed per test). Adjust the pH to between 5.4
and 5.6 with potassium citrate or citric acid, as required.
7.3 Calibration Gas. Refer to section 7.1 of Method 7E (as
applicable) for the calibration gas requirements. Example
calibration gas mixtures are listed below.
(a) SO2 in nitrogen (N2).
(b) SO2 in air.
(c) SO2 and carbon dioxide (CO2) in N2.
(d) SO2 and oxygen (O2) in N2.
(e) SO2/CO2/O2 gas mixture in N2.
(f) CO2/NOX gas mixture in N2.
(g) CO2/SO2/NOX gas mixture in N2.
For fluorescence-based analyzers, the O2 and CO2 concentrations of
the calibration gases as introduced to the analyzer must be within
1.0 percent (absolute) O2 and 1.0 percent (absolute) CO2 of the O2
and CO2 concentrations of the effluent samples as introduced to the
analyzer. Alternatively, for fluorescence-based analyzers, use
calibration blends of SO2 in air and the nomographs provided by the
vendor to determine the quenching correction factor (the effluent
O2 and CO2 concentrations must be known). This requirement does not
apply to ambient-level fluorescence analyzers that are used in
conjunction with sample dilution systems. Alternatively, H2S in O2
or air may be used to calibrate the analyzer through the tube
furnace.
7.4 System Performance Check Gas. You must use H2S (100 ppmv or
less) stored in aluminum cylinders with the concentration certified
by the manufacturer. Hydrogen sulfide in nitrogen is more stable
than H2S in air, but air may be used as the balance gas.
Note:
Alternatively, H2S recovery gas generated from a permeation
device gravimetrically calibrated and certified at some convenient
operating temperature may be used. The permeation rate of the
device must be such that at the appropriate dilution gas flow rate,
an H2S concentration can be generated in the range of the stack gas
or within 20 percent of the emission standard.
7.5 Interference Check. Examples of test gases for the
interference check are listed in Table 7E-3 of Method 7E.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Pre-sampling Tests. Before measuring emissions, perform the
following procedures:
(a) Calibration gas verification,
(b) Calibration error test,
(c) System performance check,
(d) Verification that the interference check has been
satisfied.
8.1.1 Calibration Gas Verification. Obtain a certificate from
the gas manufacturer documenting the quality of the gas. Confirm
that the manufacturer certification is complete and current. Ensure
that your calibration gas certifications have not expired. This
documentation should be available on-site for inspection. To the
extent practicable, select a high-level gas concentration that will
result in the measured emissions being between 20 and 100 percent
of the calibration span.
8.1.2 Analyzer Calibration Error Test. After you have assembled,
prepared, and calibrated your sampling system and analyzer, you
must conduct a 3-point analyzer calibration error test before the
first run and again after any failed system performance check or
failed drift test to ensure the calibration is acceptable.
Introduce the low-, mid-, and high-level calibration gases
sequentially to the analyzer in direct calibration mode. For each
calibration gas, calculate the analyzer calibration error using
Equation 16C-1 in section 12.2. The calibration error for the low-,
mid-, and high-level gases must not exceed 5.0 percent or 0.5 ppmv.
If the calibration error specification is not met, take corrective
action and repeat the test until an acceptable 3-point calibration
is achieved.
8.1.3 System Performance Check. A system performance check is
done (1) to validate the sampling train components and procedure
(prior to testing), and (2) to validate a test run (after a run).
You must conduct a performance check in the field prior to testing,
and after each 3-hour run or after three 1-hour runs. A performance
check consists of sampling and analyzing a known concentration of
H2S (system performance check gas) and comparing the analyzed
concentration to the known concentration. To conduct the system
performance check, mix the system performance check gas (Section
7.4) and ambient air, that has been conditioned to remove moisture
and sulfur-containing gases, in a dilution system such as that
shown in Figure 16A-3 of Method 16A. Alternatively, ultra-high
purity (UHP) grade air may be used. Adjust the gas flow rates to
generate an H2S concentration in the range of the stack gas or
within 20 percent of the applicable standard and an oxygen
concentration greater than 1 percent at a total flow rate of at
least 2.5 liters/min (5.3 ft3/hr). Use Equation 16A-3 from Method
16A to calculate the concentration of system performance check gas
generated. Calibrate the flow rate from both gas sources with a
soap bubble flow meter so that the diluted concentration of H2S can
be accurately calculated. Alternatively, mass flow controllers with
documented calibrations may be used if UHP grade air is being used.
Sample duration should be sufficiently long to ensure a stable
response from the analyzer. Analyze in the same manner as the
emission samples. Collect the sample through the probe of the
sampling train using a manifold or other suitable device that will
ensure extraction of a representative sample. The TRS sample
concentration measured between system performance checks is
corrected by the average of the pre- and post-system performance
checks.
8.1.4 Interference Check. Same as in Method 7E, section
8.2.7.
8.2 Measurement System Preparation.
8.2.1 For the SO2 scrubber, measure 100 ml of citrate buffer
into the first and second impingers; leave the third impinger
empty. Immerse the impingers in an ice bath, and locate them as
close as possible to the filter heat box. The connecting tubing
should be free of loops. Maintain the probe and filter temperatures
sufficiently high to prevent moisture condensation, and monitor
with a suitable temperature sensor. Prepare the oxidation furnace
and maintain at 800 ±100 °C (1472 ±180 °F).
8.2.2 Citrate Scrubber Conditioning Procedure. Condition the
citrate buffer scrubbing solution by pulling stack gas through the
Teflon impingers as described in section 8.4.1.
8.3 Pretest Procedures. After the complete measurement system
has been set up at the site and deemed to be operational, the
following procedures must be completed before sampling is
initiated.
8.3.1 Leak-Check. Appropriate leak-check procedures must be
employed to verify the integrity of all components, sample lines,
and connections. For components upstream of the sample pump, attach
the probe end of the sample line to a manometer or vacuum gauge,
start the pump and pull a vacuum greater than 50 mm (2 in.) Hg,
close off the pump outlet, and then stop the pump and ascertain
that there is no leak for 1 minute. For components after the pump,
apply a slight positive pressure and check for leaks by applying a
liquid (detergent in water, for example) at each joint. Bubbling
indicates the presence of a leak.
8.3.2 Initial System Performance Check. A system performance
check using the test gas (Section 7.4) is performed prior to
testing to validate the sampling train components and
procedure.
8.4 Sample Collection and Analysis.
8.4.1 After performing the required pretest procedures described
in section 8.1, insert the sampling probe into the test port
ensuring that no dilution air enters the stack through the port.
Condition the sampling system and citrate buffer solution for a
minimum of 15 minutes before beginning analysis. Begin sampling and
analysis. A source test consists of three test runs. A test run
shall consist of a single sample collected over a 3-hour period or
three separate 1-hour samples collected over a period not to exceed
six hours.
8.5 Post-Run Evaluations.
8.5.1 System Performance Check. Perform a post-run system
performance check before replacing the citrate buffer solution and
particulate filter and before the probe is cleaned. The check
results must not exceed the 100 ±20 percent limit set forth in
section 13.2. If this limit is exceeded, the intervening run is
considered invalid. However, if the recovery efficiency is not in
the 100 ±20 percent range, but the results do not affect the
compliance or noncompliance status of the affected facility, the
Administrator may decide to accept the results of the compliance
test.
8.5.2 Calibration Drift. After a run or series of runs, not to
exceed a 24-hour period after initial calibration, perform a
calibration drift test using a calibration gas (preferably the
level that best approximates the sample concentration) in direct
calibration mode. This drift must not differ from the initial
calibration error percent by more than 3.0 percent or 0.5 ppm. If
the drift exceeds this limit, the intervening run or runs are
considered valid, but a new analyzer calibration error test must be
performed and passed before continuing sampling.
9.0 Quality Control
Section
Quality control measure
Effect
8.1.2
Analyzer calibration error
test
Establishes initial
calibration accuracy within 5.0%.
8.1.3, 8.5.1
System performance check
Ensures accuracy of
sampling/analytical procedure to 100 ±20%.
8.5.2
Calibration drift test
Ensures calibration drift is
within 3.0%.
8.1.4
Interference check
Checks for analytical
interferences.
8.3
Sampling equipment
leak-check
Ensures accurate measurement
of sample gas flow rate, sample volume.
10.0 Calibration
10.1 Calibrate the system using the gases described in section
7.3. Perform the initial 3-point calibration error test as
described in section 8.1.2 before you start the test. The
specification in section 13 must be met. Conduct an initial system
performance test described in section 8.1.3 as well before the test
to validate the sampling components and procedures before sampling.
After the test commences, a system performance check is required
after each run. You must include a copy of the manufacturer's
certification of the calibration gases used in the testing as part
of the test report. This certification must include the 13
documentation requirements in the EPA Traceability Protocol for
Assay and Certification of Gaseous Calibration Standards, September
1997, as amended August 25, 1999.
11.0 Analytical Procedure
Because sample collection and analysis are performed together
(see section 8.0), additional discussion of the analytical
procedure is not necessary.
12.0 Calculations and Data Analysis
12.1 Nomenclature.
ACE = Analyzer calibration error, percent of calibration span. CD =
Calibration drift, percent. CDir = Measured concentration of a
calibration gas (low, mid, or high) when introduced in direct
calibration mode, ppmv. CH2S = Concentration of the system
performance check gas, ppmv H2S. CS = Measured concentration of the
system performance gas when introduced in system calibration mode,
ppmv H2S. CV = Manufacturer certified concentration of a
calibration gas (low, mid, or high), ppmv SO2. CSO2 = Unadjusted
sample SO2 concentration, ppmv. CTRS = Total reduced sulfur
concentration corrected for system performance, ppmv. CS =
Calibration span, ppmv. DF = Dilution system (if used) dilution
factor, dimensionless. SP = System performance, percent.
12.2 Analyzer Calibration Error. For non-dilution systems, use
Equation 16C-1 to calculate the analyzer calibration error for the
low-, mid-, and high-level calibration gases.
12.3 System Performance Check. Use Equation 16C-2 to calculate
the system performance.
12.4 Calibration Drift. Use Equation 16C-3 to calculate the
calibration drift at a single concentration level after a run or
series of runs (not to exceed a 24-hr period) from initial
calibration. Compare the single-level calibration gas error (ACEn)
to the original error obtained for that gas in the initial analyzer
calibration error test (ACEi).
12.5 TRS Concentration as SO2. For each sample or test run,
calculate the arithmetic average of SO2 concentration values (e.g.,
1-minute averages). Then calculate the sample TRS concentration by
adjusting the average value of CSO2 for system performance using
Equation 16C-4.
13.0
Method Performance
13.1 Analyzer Calibration Error. At each calibration gas level
(low, mid, and high), the calibration error must either not exceed
5.0 percent of the calibration span or |CDir−Cv| must be ≤0.5
ppmv.
13.2 System Performance. Each system performance check must not
deviate from the system performance gas concentration by more than
20 percent. Alternatively, the results are acceptable if |Cs−CH2S|
is ≤0.5 ppmv.
13.3 Calibration Drift. The calibration drift at the end of any
run or series of runs within a 24-hour period must not differ by
more than 3.0 percent from the original ACE at the test
concentration level or |ACEi−ACEn| must not exceed 0.5 ppmv.
13.4 Interference Check. For the analyzer, the total
interference response (i.e., the sum of the interference responses
of all tested gaseous components) must not be greater than 2.5
percent of the calibration span. Any interference is also
acceptable if the sum of the responses does not exceed 0.5 ppmv for
a calibration span of 5 to 10 ppmv, or 0.2 ppmv for a calibration
span <5 ppmv.
14.0 Pollution Prevention [Reserved] 15.0 Waste Management
[Reserved] 16.0 References 1. The references are the same as in
section 16.0 of Method 16, section 17.0 of Method 16A, and section
17.0 of Method 6C. 2. National Council of the Paper Industry for
Air and Stream Improvement, Inc,. A Study of TRS Measurement
Methods. Technical Bulletin No. 434. New York, NY. May 1984. 12p.
3. Margeson, J.H., J.E. Knoll, and M.R. Midgett. A Manual Method
for TRS Determination. Draft available from the authors. Source
Branch, Quality Assurance Division, U.S. Environmental Protection
Agency, Research Triangle Park, NC 27711. 17.0 Tables, Diagrams,
Flowcharts, and Validation Data [Reserved] Method 17 -
Determination of Particulate Matter Emissions From Stationary
Sources Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, Method
5.
1.0 Scope and Application
1.1 Analyte. Particulate matter (PM). No CAS number
assigned.
Note:
Particulate matter is not an absolute quantity. It is a function
of temperature and pressure. Therefore, to prevent variability in
PM emission regulations and/or associated test methods, the
temperature and pressure at which PM is to be measured must be
carefully defined. Of the two variables (i.e., temperature
and pressure), temperature has the greater effect upon the amount
of PM in an effluent gas stream; in most stationary source
categories, the effect of pressure appears to be negligible. In
Method 5, 120 °C (248 °F) is established as a nominal reference
temperature. Thus, where Method 5 is specified in an applicable
subpart of the standard, PM is defined with respect to temperature.
In order to maintain a collection temperature of 120 °C (248 °F),
Method 5 employs a heated glass sample probe and a heated filter
holder. This equipment is somewhat cumbersome and requires care in
its operation. Therefore, where PM concentrations (over the normal
range of temperature associated with a specified source category)
are known to be independent of temperature, it is desirable to
eliminate the glass probe and the heating systems, and to sample at
stack temperature.
1.2 Applicability. This method is applicable for the
determination of PM emissions, where PM concentrations are known to
be independent of temperature over the normal range of temperatures
characteristic of emissions from a specified source category. It is
intended to be used only when specified by an applicable subpart of
the standards, and only within the applicable temperature limits
(if specified), or when otherwise approved by the Administrator.
This method is not applicable to stacks that contain liquid
droplets or are saturated with water vapor. In addition, this
method shall not be used as written if the projected
cross-sectional area of the probe extension-filter holder assembly
covers more than 5 percent of the stack cross-sectional area (see
section 8.1.2).
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 Particulate matter is withdrawn isokinetically from the
source and collected on a glass fiber filter maintained at stack
temperature. The PM mass is determined gravimetrically after the
removal of uncombined water.
3.0 Definitions
Same as Method 5, section 3.0.
4.0 Interferences [Reserved] 5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies
6.1 Sampling Train. A schematic of the sampling train used in
this method is shown in Figure 17-1. The sampling train components
and operation and maintenance are very similar to Method 5, which
should be consulted for details.
6.1.1 Probe Nozzle, Differential Pressure Gauge, Metering
System, Barometer, Gas Density Determination Equipment. Same as in
Method 5, sections 6.1.1, 6.1.4, 6.1.8, 6.1.9, and 6.1.10,
respectively.
6.1.2 Filter Holder. The in-stack filter holder shall be
constructed of borosilicate or quartz glass, or stainless steel. If
a gasket is used, it shall be made of silicone rubber, Teflon, or
stainless steel. Other holder and gasket materials may be used,
subject to the approval of the Administrator. The filter holder
shall be designed to provide a positive seal against leakage from
the outside or around the filter.
6.1.3 Probe Extension. Any suitable rigid probe extension may be
used after the filter holder.
6.1.4 Pitot Tube. Same as in Method 5, section 6.1.3.
6.1.4.1 It is recommended (1) that the pitot tube have a known
baseline coefficient, determined as outlined in section 10 of
Method 2; and (2) that this known coefficient be preserved by
placing the pitot tube in an interference-free arrangement with
respect to the sampling nozzle, filter holder, and temperature
sensor (see Figure 17-1). Note that the 1.9 cm ( 3/4-in.)
free-space between the nozzle and pitot tube shown in Figure 17-1,
is based on a 1.3 cm ( 1/2-in.) ID nozzle. If the sampling train is
designed for sampling at higher flow rates than that described in
APTD-0581, thus necessitating the use of larger sized nozzles, the
free-space shall be 1.9 cm ( 3/4-in.) with the largest sized nozzle
in place.
6.1.4.2 Source-sampling assemblies that do not meet the minimum
spacing requirements of Figure 17-1 (or the equivalent of these
requirements, e.g., Figure 2-4 of Method 2) may be used;
however, the pitot tube coefficients of such assemblies shall be
determined by calibration, using methods subject to the approval of
the Administrator.
6.1.5 Condenser. It is recommended that the impinger system or
alternatives described in Method 5 be used to determine the
moisture content of the stack gas. Flexible tubing may be used
between the probe extension and condenser. Long tubing lengths may
affect the moisture determination.
6.2 Sample Recovery. Probe-liner and probe-nozzle brushes, wash
bottles, glass sample storage containers, petri dishes, graduated
cylinder and/or balance, plastic storage containers, funnel and
rubber policeman, funnel. Same as in Method 5, sections 6.2.1
through 6.2.8, respectively.
6.3 Sample Analysis. Glass weighing dishes, desiccator,
analytical balance, balance, beakers, hygrometer, temperature
sensor. Same as in Method 5, sections 6.3.1 through 6.3.7,
respectively.
7.0 Reagents and Standards
7.1 Sampling. Filters, silica gel, water, crushed ice, stopcock
grease. Same as in Method 5, sections 7.1.1, 7.1.2, 7.1.3, 7.1.4,
and 7.1.5, respectively. Thimble glass fiber filters may also be
used.
7.2 Sample Recovery. Acetone (reagent grade). Same as in Method
5, section 7.2.
7.3 Sample Analysis. Acetone and Desiccant. Same as in Method 5,
sections 7.3.1 and 7.3.2, respectively.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Sampling.
8.1.1 Pretest Preparation. Same as in Method 5, section
8.1.1.
8.1.2 Preliminary Determinations. Same as in Method 5, section
8.1.2, except as follows: Make a projected-area model of the probe
extension-filter holder assembly, with the pitot tube face openings
positioned along the centerline of the stack, as shown in Figure
17-2. Calculate the estimated cross-section blockage, as shown in
Figure 17-2. If the blockage exceeds 5 percent of the duct cross
sectional area, the tester has the following options exist: (1) a
suitable out-of-stack filtration method may be used instead of
in-stack filtration; or (2) a special in-stack arrangement, in
which the sampling and velocity measurement sites are separate, may
be used; for details concerning this approach, consult with the
Administrator (see also Reference 1 in section 17.0). Select a
probe extension length such that all traverse points can be
sampled. For large stacks, consider sampling from opposite sides of
the stack to reduce the length of probes.
8.1.3 Preparation of Sampling Train. Same as in Method 5,
section 8.1.3, except the following: Using a tweezer or clean
disposable surgical gloves, place a labeled (identified) and
weighed filter in the filter holder. Be sure that the filter is
properly centered and the gasket properly placed so as not to allow
the sample gas stream to circumvent the filter. Check filter for
tears after assembly is completed. Mark the probe extension with
heat resistant tape or by some other method to denote the proper
distance into the stack or duct for each sampling point. Assemble
the train as in Figure 17-1, using a very light coat of silicone
grease on all ground glass joints and greasing only the outer
portion (see APTD-0576) to avoid possibility of contamination by
the silicone grease. Place crushed ice around the impingers.
8.1.4 Leak-Check Procedures. Same as in Method 5, section 8.1.4,
except that the filter holder is inserted into the stack during the
sampling train leak-check. To do this, plug the inlet to the probe
nozzle with a material that will be able to withstand the stack
temperature. Insert the filter holder into the stack and wait
approximately 5 minutes (or longer, if necessary) to allow the
system to come to equilibrium with the temperature of the stack gas
stream.
8.1.5 Sampling Train Operation. The operation is the same as in
Method 5. Use a data sheet such as the one shown in Figure 5-3 of
Method 5, except that the filter holder temperature is not
recorded.
8.1.6 Calculation of Percent Isokinetic. Same as in Method 5,
section 12.11.
8.2 Sample Recovery.
8.2.1 Proper cleanup procedure begins as soon as the probe
extension assembly is removed from the stack at the end of the
sampling period. Allow the assembly to cool.
8.2.2 When the assembly can be safely handled, wipe off all
external particulate matter near the tip of the probe nozzle and
place a cap over it to prevent losing or gaining particulate
matter. Do not cap off the probe tip tightly while the sampling
train is cooling down as this would create a vacuum in the filter
holder, forcing condenser water backward.
8.2.3 Before moving the sample train to the cleanup site,
disconnect the filter holder-probe nozzle assembly from the probe
extension; cap the open inlet of the probe extension. Be careful
not to lose any condensate, if present. Remove the umbilical cord
from the condenser outlet and cap the outlet. If a flexible line is
used between the first impinger (or condenser) and the probe
extension, disconnect the line at the probe extension and let any
condensed water or liquid drain into the impingers or condenser.
Disconnect the probe extension from the condenser; cap the probe
extension outlet. After wiping off the silicone grease, cap off the
condenser inlet. Ground glass stoppers, plastic caps, or serum caps
(whichever are appropriate) may be used to close these
openings.
8.2.4 Transfer both the filter holder-probe nozzle assembly and
the condenser to the cleanup area. This area should be clean and
protected from the wind so that the chances of contaminating or
losing the sample will be minimized.
8.2.5 Save a portion of the acetone used for cleanup as a blank.
Take 200 ml of this acetone from the wash bottle being used and
place it in a glass sample container labeled “acetone blank.”
Inspect the train prior to and during disassembly and not any
abnormal conditions. Treat the sample as discussed in Method 5,
section 8.2.
9.0 Quality Control [Reserved] 10.0 Calibration and Standardization
The calibrations of the probe nozzle, pitot tube, metering
system, temperature sensors, and barometer are the same as in
Method 5, sections 10.1 through 10.3, 10.5, and 10.6,
respectively.
11.0 Analytical Procedure
Same as in Method 5, section 11.0. Analytical data should be
recorded on a form similar to that shown in Figure 5-6 of Method
5.
Same as in Method 5, section 17.0, with the addition of the
following:
1. Vollaro, R.F. Recommended Procedure for Sample Traverses in
Ducts Smaller than 12 Inches in Diameter. U.S. Environmental
Protection Agency, Emission Measurement Branch. Research Triangle
Park, NC. November 1976.
18.0 Tables, Diagrams, Flowcharts, and Validation Data Method 18 -
Measurement of Gaseous Organic Compound Emissions By Gas
Chromatography Note:
This method is not inclusive with respect to specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3.
Note:
This method should not be attempted by persons unfamiliar with
the performance characteristics of gas chromatography, nor by those
persons who are unfamiliar with source sampling. Particular care
should be exercised in the area of safety concerning choice of
equipment and operation in potentially explosive atmospheres.
1.0 Scope and Application
1.1 Analyte. Total gaseous organic compounds.
1.2 Applicability.
1.2.1 This method is designed to measure gaseous organics
emitted from an industrial source. While designed for ppm level
sources, some detectors are quite capable of detecting compounds at
ambient levels, e.g., ECD, ELCD, and helium ionization
detectors. Some other types of detectors are evolving such that the
sensitivity and applicability may well be in the ppb range in only
a few years.
1.2.2 This method will not determine compounds that (1) are
polymeric (high molecular weight), (2) can polymerize before
analysis, or (3) have very low vapor pressures at stack or
instrument conditions.
1.3 Range. The lower range of this method is determined by the
sampling system; adsorbents may be used to concentrate the sample,
thus lowering the limit of detection below the 1 part per million
(ppm) typically achievable with direct interface or bag sampling.
The upper limit is governed by GC detector saturation or column
overloading; the upper range can be extended by dilution of sample
with an inert gas or by using smaller volume gas sampling loops.
The upper limit can also be governed by condensation of higher
boiling compounds.
1.4 Sensitivity. The sensitivity limit for a compound is defined
as the minimum detectable concentration of that compound, or the
concentration that produces a signal-to-noise ratio of three to
one. The minimum detectable concentration is determined during the
presurvey calibration for each compound.
2.0 Summary of Method
The major organic components of a gas mixture are separated by
gas chromatography (GC) and individually quantified by flame
ionization, photoionization, electron capture, or other appropriate
detection principles. The retention times of each separated
component are compared with those of known compounds under
identical conditions. Therefore, the analyst confirms the identity
and approximate concentrations of the organic emission components
beforehand. With this information, the analyst then prepares or
purchases commercially available standard mixtures to calibrate the
GC under conditions identical to those of the samples. The analyst
also determines the need for sample dilution to avoid detector
saturation, gas stream filtration to eliminate particulate matter,
and prevention of moisture condensation.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Resolution interferences that may occur can be eliminated by
appropriate GC column and detector choice or by shifting the
retention times through changes in the column flow rate and the use
of temperature programming.
4.2 The analytical system is demonstrated to be essentially free
from contaminants by periodically analyzing blanks that consist of
hydrocarbon-free air or nitrogen.
4.3 Sample cross-contamination that occurs when high-level and
low-level samples or standards are analyzed alternately is best
dealt with by thorough purging of the GC sample loop between
samples.
4.4 To assure consistent detector response, calibration gases
are contained in dry air. To adjust gaseous organic concentrations
when water vapor is present in the sample, water vapor
concentrations are determined for those samples, and a correction
factor is applied.
4.5 The gas chromatograph run time must be sufficient to clear
all eluting peaks from the column before proceeding to the next run
(in order to prevent sample carryover).
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method. The analyzer users manual should be consulted for
specific precautions to be taken with regard to the analytical
procedure.
6.0 Equipment and Supplies
6.1 Equipment needed for the presurvey sampling procedure can be
found in section 16.1.1.
6.2 Equipment needed for the integrated bag sampling and
analysis procedure can be found in section 8.2.1.1.1.
6.3 Equipment needed for direct interface sampling and analysis
can be found in section 8.2.2.1.
6.4 Equipment needed for the dilution interface sampling and
analysis can be found in section 8.2.3.1.
6.5 Equipment needed for adsorbent tube sampling and analysis
can be found in section 8.2.4.1.
7.0 Reagents and Standards
7.1 Reagents needed for the presurvey sampling procedure can be
found in section 16.1.2.
8.0 Sample Collection, Preservation, Storage, and Transport
8.2 Final Sampling and Analysis Procedure. Considering safety
(flame hazards) and the source conditions, select an appropriate
sampling and analysis procedure (Section 8.2.1, 8.2.2, 8.2.3 or
8.2.4). In situations where a hydrogen flame is a hazard and no
intrinsically safe GC is suitable, use the flexible bag collection
technique or an adsorption technique.
8.2.1 Integrated Bag Sampling and Analysis.
8.2.1.1 Evacuated Container Sampling Procedure. In this
procedure, the bags are filled by evacuating the rigid air-tight
container holding the bags. Use a field sample data sheet as shown
in Figure 18-10. Collect triplicate samples from each sample
location.
8.2.1.1.1 Apparatus.
8.2.1.1.1.1 Probe. Stainless steel, Pyrex glass, or Teflon
tubing probe, according to the duct temperature, with Teflon tubing
of sufficient length to connect to the sample bag. Use stainless
steel or Teflon unions to connect probe and sample line.
8.2.1.1.1.2 Quick Connects. Male (2) and female (2) of stainless
steel construction.
8.2.1.1.1.3 Needle Valve. To control gas flow.
8.2.1.1.1.4 Pump. Leakless Teflon-coated diaphragm-type pump or
equivalent. To deliver at least 1 liter/min.
8.2.1.1.1.5 Charcoal Adsorption Tube. Tube filled with activated
charcoal, with glass wool plugs at each end, to adsorb organic
vapors.
8.2.1.1.1.6 Flowmeter. 0 to 500-ml flow range; with
manufacturer's calibration curve.
8.2.1.1.2 Sampling Procedure. To obtain a sample, assemble the
sample train as shown in Figure 18-9. Leak-check both the bag and
the container. Connect the vacuum line from the needle valve to the
Teflon sample line from the probe. Place the end of the probe at
the centroid of the stack or at a point no closer to the walls than
1 in., and start the pump. Set the flow rate so that the final
volume of the sample is approximately 80 percent of the bag
capacity. After allowing sufficient time to purge the line several
times, connect the vacuum line to the bag, and evacuate until the
rotameter indicates no flow. Then position the sample and vacuum
lines for sampling, and begin the actual sampling, keeping the rate
proportional to the stack velocity. As a precaution, direct the gas
exiting the rotameter away from sampling personnel. At the end of
the sample period, shut off the pump, disconnect the sample line
from the bag, and disconnect the vacuum line from the bag
container. Record the source temperature, barometric pressure,
ambient temperature, sampling flow rate, and initial and final
sampling time on the data sheet shown in Figure 18-10. Protect the
bag and its container from sunlight. Record the time lapsed between
sample collection and analysis, and then conduct the recovery
procedure in Section 8.4.2.
8.2.1.2 Direct Pump Sampling Procedure. Follow 8.2.1.1, except
place the pump and needle valve between the probe and the bag. Use
a pump and needle valve constructed of inert material not affected
by the stack gas. Leak-check the system, and then purge with stack
gas before connecting to the previously evacuated bag.
8.2.1.3 Explosion Risk Area Bag Sampling Procedure. Follow
8.2.1.1 except replace the pump with another evacuated can (see
Figure 18-9a). Use this method whenever there is a possibility of
an explosion due to pumps, heated probes, or other flame producing
equipment.
8.2.1.4 Other Modified Bag Sampling Procedures. In the event
that condensation is observed in the bag while collecting the
sample and a direct interface system cannot be used, heat the bag
during collection and maintain it at a suitably elevated
temperature during all subsequent operations. (Note: Take care to
leak-check the system prior to the dilutions so as not to create a
potentially explosive atmosphere.) As an alternative, collect the
sample gas, and simultaneously dilute it in the bag.
8.2.1.4.1 First Alternative Procedure. Heat the box containing
the sample bag to 120 °C (±5 °C). Then transport the bag as rapidly
as possible to the analytical area while maintaining the heating,
or cover the box with an insulating blanket. In the analytical
area, keep the box heated to 120 °C (±5 °C) until analysis. Be sure
that the method of heating the box and the control for the heating
circuit are compatible with the safety restrictions required in
each area.
8.2.1.4.2 Second Alternative Procedure. Prefill the bag with a
known quantity of inert gas. Meter the inert gas into the bag
according to the procedure for the preparation of gas concentration
standards of volatile liquid materials (Section 10.1.2.2), but
eliminate the midget impinger section. Take the partly filled bag
to the source, and meter the source gas into the bag through heated
sampling lines and a heated flowmeter, or Teflon positive
displacement pump. Verify the dilution factors before sampling each
bag through dilution and analysis of gases of known
concentration.
8.2.1.5 Analysis of Bag Samples.
8.2.1.5.1 Apparatus. Same as section 8.1. A minimum of three gas
standards are required.
8.2.1.5.2 Procedure.
8.2.1.5.2.1 Establish proper GC operating conditions as
described in section 10.2, and record all data listed in Figure
18-7. Prepare the GC so that gas can be drawn through the sample
valve. Flush the sample loop with calibration gas mixture, and
activate the valve (sample pressure at the inlet to the GC
introduction valve should be similar during calibration as during
actual sample analysis). Obtain at least three chromatograms for
the mixture. The results are acceptable when the peak areas for the
three injections agree to within 5 percent of their average. If
they do not agree, run additional samples or correct the analytical
techniques until this requirement is met. Then analyze the other
two calibration mixtures in the same manner. Prepare a calibration
curve as described in section 10.2.
8.2.1.5.2.2 Analyze the three source gas samples by connecting
each bag to the sampling valve with a piece of Teflon tubing
identified with that bag. Analyze each bag sample three times.
Record the data in Figure 18-11. If certain items do not apply, use
the notation “N.A.” If the bag has been maintained at an elevated
temperature as described in section 8.2.1.4, determine the stack
gas water content by Method 4. After all samples have been
analyzed, repeat the analysis of the mid-level calibration gas for
each compound. Compare the average response factor of the pre- and
post-test analysis for each compound. If they differ by
>5percent, analyze the other calibration gas levels for that
compound, and prepare a calibration curve using all the pre- and
post-test calibration gas mixture values. If the two response
factor averages (pre-and post-test) differ by less than 5 percent
from their mean value, the tester has the option of using only the
pre-test calibration curve to generate the concentration
values.
8.2.1.6 Determination of Bag Water Vapor Content. Measure the
ambient temperature and barometric pressure near the bag. From a
water saturation vapor pressure table, determine and record the
water vapor content of the bag as a decimal figure. (Assume the
relative humidity to be 100 percent unless a lesser value is
known.) If the bag has been maintained at an elevated temperature
as described in section 8.2.1.4, determine the stack gas water
content by Method 4.
8.2.1.8 Emission Calculations. From the calibration curve
described in section 8.2.1.5, select the value of Cs that
corresponds to the peak area. Calculate the concentration Cc in
ppm, dry basis, of each organic in the sample using Equation 18-5
in section 12.6.
8.2.2 Direct Interface Sampling and Analysis Procedure. The
direct interface procedure can be used provided that the moisture
content of the gas does not interfere with the analysis procedure,
the physical requirements of the equipment can be met at the site,
and the source gas concentration falls within the linear range of
the detector. Adhere to all safety requirements with this
method.
8.2.2.1 Apparatus.
8.2.2.1.1 Probe. Constructed of stainless steel, Pyrex glass, or
Teflon tubing as dictated by duct temperature and reactivity of
target compounds. A filter or glass wool plug may be needed if
particulate is present in the stack gas. If necessary, heat the
probe with heating tape or a special heating unit capable of
maintaining a temperature greater than 110 °C.
8.2.2.1.2 Sample Lines. 6.4-mm OD (or other diameter as needed)
Teflon lines, heat-traced to prevent condensation of material
(greater than 110 °C).
8.2.2.1.3 Quick Connects. To connect sample line to gas sampling
valve on GC instrument and to pump unit used to withdraw source
gas. Use a quick connect or equivalent on the cylinder or bag
containing calibration gas to allow connection of the calibration
gas to the gas sampling valve.
8.2.2.1.4 Thermocouple Readout Device. Potentiometer or digital
thermometer, to measure source temperature and probe
temperature.
8.2.2.1.5 Heated Gas Sampling Valve. Of two-position, six-port
design, to allow sample loop to be purged with source gas or to
direct source gas into the GC instrument.
8.2.2.1.6 Needle Valve. To control gas sampling rate from the
source.
8.2.2.1.7 Pump. Leakless Teflon-coated diaphragm-type pump or
equivalent, capable of at least 1 liter/minute sampling rate.
8.2.2.1.8 Flowmeter. Of suitable range to measure sampling
rate.
8.2.2.1.9 Charcoal Adsorber. To adsorb organic vapor vented from
the source to prevent exposure of personnel to source gas.
8.2.2.1.10 Gas Cylinders. Carrier gas, oxygen and fuel as needed
to run GC and detector.
8.2.2.1.11 Gas Chromatograph. Capable of being moved into the
field, with detector, heated gas sampling valve, column required to
complete separation of desired components, and option for
temperature programming.
8.2.2.1.12 Recorder/Integrator. To record results.
8.2.2.2 Procedure. Calibrate the GC using the procedures in
section 8.2.1.5.2.1. To obtain a stack gas sample, assemble the
sampling system as shown in Figure 18-12. Make sure all connections
are tight. Turn on the probe and sample line heaters. As the
temperature of the probe and heated line approaches the target
temperature as indicated on the thermocouple readout device,
control the heating to maintain a temperature greater than 110 °C.
Conduct a 3-point calibration of the GC by analyzing each gas
mixture in triplicate. Generate a calibration curve. Place the
inlet of the probe at the centroid of the duct, or at a point no
closer to the walls than 1 m, and draw source gas into the probe,
heated line, and sample loop. After thorough flushing, analyze the
stack gas sample using the same conditions as for the calibration
gas mixture. For each run, sample, analyze, and record five
consecutive samples. A test consists of three runs (five samples
per run times three runs, for a total of fifteen samples). After
all samples have been analyzed, repeat the analysis of the
mid-level calibration gas for each compound. For each calibration
standard, compare the pre- and post-test average response factors
(RF) for each compound. If the two calibration RF values (pre- and
post-analysis) differ by more than 5 percent from their mean value,
then analyze the other calibration gas levels for that compound and
determine the stack gas sample concentrations by comparison to both
calibration curves (this is done by preparing a calibration curve
using all the pre- and post-test calibration gas mixture values.)
If the two calibration RF values differ by less than 5 percent from
their mean value, the tester has the option of using only the
pre-test calibration curve to generate the concentration values.
Record this calibration data and the other required data on the
data sheet shown in Figure 18-11, deleting the dilution gas
information.
Note:
Take care to draw all samples and calibration mixtures through
the sample loop at the same pressure.
8.2.2.3 Determination of Stack Gas Moisture Content. Use Method
4 to measure the stack gas moisture content.
8.2.2.5 Emission Calculations. Same as section 8.2.1.8.
8.2.3 Dilution Interface Sampling and Analysis Procedure. Source
samples that contain a high concentration of organic materials may
require dilution prior to analysis to prevent saturating the GC
detector. The apparatus required for this direct interface
procedure is basically the same as that described in the section
8.2.2, except a dilution system is added between the heated sample
line and the gas sampling valve. The apparatus is arranged so that
either a 10:1 or 100:1 dilution of the source gas can be directed
to the chromatograph. A pump of larger capacity is also required,
and this pump must be heated and placed in the system between the
sample line and the dilution apparatus.
8.2.3.1 Apparatus. The equipment required in addition to that
specified for the direct interface system is as follows:
8.2.3.1.1 Sample Pump. Leakless Teflon-coated diaphragm-type
that can withstand being heated to 120 °C and deliver 1.5
liters/minute.
8.2.3.1.2 Dilution Pumps. Two Model A-150 Komhyr Teflon positive
displacement type delivering 150 cc/minute, or equivalent. As an
option, calibrated flowmeters can be used in conjunction with
Teflon-coated diaphragm pumps.
8.2.3.1.3 Valves. Two Teflon three-way valves, suitable for
connecting to Teflon tubing.
8.2.3.1.4 Flowmeters. Two, for measurement of diluent gas.
8.2.3.1.5 Diluent Gas with Cylinders and Regulators. Gas can be
nitrogen or clean dry air, depending on the nature of the source
gases.
8.2.3.1.6 Heated Box. Suitable for being heated to 120 °C, to
contain the three pumps, three-way valves, and associated
connections. The box should be equipped with quick connect fittings
to facilitate connection of: (1) the heated sample line from the
probe, (2) the gas sampling valve, (3) the calibration gas
mixtures, and (4) diluent gas lines. A schematic diagram of the
components and connections is shown in Figure 18-13. The heated box
shown in Figure 18-13 is designed to receive a heated line from the
probe. An optional design is to build a probe unit that attaches
directly to the heated box. In this way, the heated box contains
the controls for the probe heaters, or, if the box is placed
against the duct being sampled, it may be possible to eliminate the
probe heaters. In either case, a heated Teflon line is used to
connect the heated box to the gas sampling valve on the
chromatograph.
Note:
Care must be taken to leak-check the system prior to the
dilutions so as not to create a potentially explosive
atmosphere.
8.2.3.2 Procedure.
8.2.3.2.1 Assemble the apparatus by connecting the heated box,
shown in Figure 18-13, between the heated sample line from the
probe and the gas sampling valve on the chromatograph. Vent the
source gas from the gas sampling valve directly to the charcoal
filter, eliminating the pump and rotameter. Heat the sample probe,
sample line, and heated box. Insert the probe and source
thermocouple at the centroid of the duct, or to a point no closer
to the walls than 1 m. Measure the source temperature, and adjust
all heating units to a temperature 0 to 3 °C above this
temperature. If this temperature is above the safe operating
temperature of the Teflon components, adjust the heating to
maintain a temperature high enough to prevent condensation of water
and organic compounds (greater than 110 °C). Calibrate the GC
through the dilution system by following the procedures in section
8.2.1.5.2.1. Determine the concentration of the diluted calibration
gas using the dilution factor and the certified concentration of
the calibration gas. Record the pertinent data on the data sheet
shown in Figure 18-11.
8.2.3.2.2 Once the dilution system and GC operations are
satisfactory, proceed with the analysis of source gas, maintaining
the same dilution settings as used for the standards.
8.2.3.2.3 Analyze the audit samples using either the dilution
system, or directly connect to the gas sampling valve as required.
Record all data and report the results to the audit supervisor.
8.2.3.3 Determination of Stack Gas Moisture Content. Same as
section 8.2.2.3.
8.2.3.4 Quality Assurance. Same as section 8.2.2.4.
8.2.3.5 Emission Calculations. Same as section 8.2.2.5, with the
dilution factor applied.
8.2.4 Adsorption Tube Procedure. Any commercially available
adsorbent is allowed for the purposes of this method, as long as
the recovery study criteria in section 8.4.3 are met. Help in
choosing the adsorbent may be found by calling the distributor, or
the tester may refer to National Institute for Occupational Safety
and Health (NIOSH) methods for the particular organics to be
sampled. For some adsorbents, the principal interferent will be
water vapor. If water vapor is thought to be a problem, the tester
may place a midget impinger in an ice bath before the adsorbent
tubes. If this option is chosen, the water catch in the midget
impinger shall be analyzed for the target compounds. Also, the
spike for the recovery study (in section 8.4.3) shall be conducted
in both the midget impinger and the adsorbent tubes. The combined
recovery (add the recovered amount in the impinger and the
adsorbent tubes to calculate R) shall then meet the criteria in
section 8.4.3.
Note:
Post-test leak-checks are not allowed for this technique since
this can result in sample contamination.
8.2.4.1 Additional Apparatus. The following items (or
equivalent) are suggested.
8.2.4.1.1 Probe. Borosilicate glass or stainless steel,
approximately 6-mm ID, with a heating system if water condensation
is a problem, and a filter (either in-stack or out-of-stack, heated
to stack temperature) to remove particulate matter. In most
instances, a plug of glass wool is a satisfactory filter.
8.2.4.1.2 Flexible Tubing. To connect probe to adsorption tubes.
Use a material that exhibits minimal sample adsorption.
8.2.4.1.3 Leakless Sample Pump. Flow controlled, constant rate
pump, with a set of limiting (sonic) orifices.
8.2.4.1.4 Bubble-Tube Flowmeter. Volume accuracy within 1
percent, to calibrate pump.
8.2.4.1.5 Stopwatch. To time sampling and pump rate
calibration.
8.2.4.1.6 Adsorption Tubes. Precleaned adsorbent, with mass of
adsorbent to be determined by calculating breakthrough volume and
expected concentration in the stack.
8.2.4.1.7 Barometer. Accurate to 5 mm Hg, to measure atmospheric
pressure during sampling and pump calibration.
8.2.4.1.8 Rotameter. O to 100 cc/min, to detect changes in flow
rate during sampling.
8.2.4.2 Sampling and Analysis.
8.2.4.2.1 Calibrate the pump and limiting orifice flow rate
through adsorption tubes with the bubble tube flowmeter before
sampling. The sample system can be operated as a “recirculating
loop” for this operation. Record the ambient temperature and
barometric pressure. Then, during sampling, use the rotameter to
verify that the pump and orifice sampling rate remains
constant.
8.2.4.2.2 Use a sample probe, if required, to obtain the sample
at the centroid of the duct or at a point no closer to the walls
than 1 m. Minimize the length of flexible tubing between the probe
and adsorption tubes. Several adsorption tubes can be connected in
series, if the extra adsorptive capacity is needed. Adsorption
tubes should be maintained vertically during the test in order to
prevent channeling. Provide the gas sample to the sample system at
a pressure sufficient for the limiting orifice to function as a
sonic orifice. Record the total time and sample flow rate (or the
number of pump strokes), the barometric pressure, and ambient
temperature. Obtain a total sample volume commensurate with the
expected concentration(s) of the volatile organic(s) present and
recommended sample loading factors (weight sample per weight
adsorption media). Laboratory tests prior to actual sampling may be
necessary to predetermine this volume. If water vapor is present in
the sample at concentrations above 2 to 3 percent, the adsorptive
capacity may be severely reduced. Operate the gas chromatograph
according to the manufacturer's instructions. After establishing
optimum conditions, verify and document these conditions during all
operations. Calibrate the instrument and then analyze the emission
samples.
8.2.4.3 Standards and Calibration. If using thermal desorption,
obtain calibration gases using the procedures in section 10.1. If
using solvent extraction, prepare liquid standards in the
desorption solvent. Use a minimum of three different standards;
select the concentrations to bracket the expected average sample
concentration. Perform the calibration before and after each day's
sample analyses using the procedures in section 8.2.1.5.2.1.
8.2.4.4 Quality Assurance.
8.2.4.4.1 Determine the recovery efficiency of the pollutants of
interest according to section 8.4.3.
8.2.4.4.2 Determination of Sample Collection Efficiency
(Optional). If sample breakthrough is thought to be a problem, a
routine procedure for determining breakthrough is to analyze the
primary and backup portions of the adsorption tubes separately. If
the backup portion exceeds 10 percent of the total amount (primary
and back-up), it is usually a sign of sample breakthrough. For the
purposes of this method, only the recovery efficiency value
(Section 8.4.3) is used to determine the appropriateness of the
sampling and analytical procedure.
8.2.4.4.3 Volume Flow Rate Checks. Perform this check
immediately after sampling with all sampling train components in
place. Use the bubble-tube flowmeter to measure the pump volume
flow rate with the orifice used in the test sampling, and record
the result. If it has changed by more than 5 but less than 20
percent, calculate an average flow rate for the test. If the flow
rate has changed by more than 20 percent, recalibrate the pump and
repeat the sampling.
8.2.4.4.4 Calculations. Correct all sample volumes to standard
conditions. If a sample dilution system has been used, multiply the
results by the appropriate dilution ratio. Correct all results
according to the applicable procedure in section 8.4.3. Report
results as ppm by volume, dry basis.
8.3 Reporting of Results. At the completion of the field
analysis portion of the study, ensure that the data sheets shown in
Figure 18-11 have been completed. Summarize this data on the data
sheets shown in Figure 18-15.
8.4 Recovery Study. After conducting the presurvey and
identifying all of the pollutants of interest, conduct the
appropriate recovery study during the test based on the sampling
system chosen for the compounds of interest.
8.4.1 Recovery Study for Direct Interface or Dilution Interface
Sampling. If the procedures in section 8.2.2 or 8.2.3 are to be
used to analyze the stack gas, conduct the calibration procedure as
stated in section 8.2.2.2 or 8.2.3.2, as appropriate. Upon
successful completion of the appropriate calibration procedure,
attach the mid-level calibration gas for at least one target
compound to the inlet of the probe or as close as possible to the
inlet of the probe, but before the filter. Repeat the calibration
procedure by sampling and analyzing the mid-level calibration gas
through the entire sampling and analytical system in triplicate.
The mean of the calibration gas response sampled through the probe
shall be within 10 percent of the analyzer response. If the
difference in the two means is greater than 10 percent, check for
leaks throughout the sampling system and repeat the analysis of the
standard through the sampling system until this criterion is
met.
8.4.2 Recovery Study for Bag Sampling.
8.4.2.1 Follow the procedures for the bag sampling and analysis
in section 8.2.1. After analyzing all three bag samples, choose one
of the bag samples and tag this bag as the spiked bag. Spike the
chosen bag sample with a known mixture (gaseous or liquid) of all
of the target pollutants. The theoretical concentration, in ppm, of
each spiked compound in the bag shall be 40 to 60 percent of the
average concentration measured in the three bag samples. If a
target compound was not detected in the bag samples, the
concentration of that compound to be spiked shall be 5 times the
limit of detection for that compound. Store the spiked bag for the
same period of time as the bag samples collected in the field.
After the appropriate storage time has passed, analyze the spiked
bag three times. Calculate the average fraction recovered (R) of
each spiked target compound with the equation in section 12.7.
8.4.2.2 For the bag sampling technique to be considered valid
for a compound, 0.70 ≤R ≤1.30. If the R value does not meet this
criterion for a target compound, the sampling technique is not
acceptable for that compound, and therefore another sampling
technique shall be evaluated for acceptance (by repeating the
recovery study with another sampling technique). Report the R value
in the test report and correct all field measurements with the
calculated R value for that compound by using the equation in
section 12.8.
8.4.3 Recovery Study for Adsorption Tube Sampling. If following
the adsorption tube procedure in section 8.2.4, conduct a recovery
study of the compounds of interest during the actual field test.
Set up two identical sampling trains. Collocate the two sampling
probes in the stack. The probes shall be placed in the same
horizontal plane, where the first probe tip is 2.5 cm from the
outside edge of the other. One of the sampling trains shall be
designated the spiked train and the other the unspiked train. Spike
all of the compounds of interest (in gaseous or liquid form) onto
the adsorbent tube(s) in the spiked train before sampling. The mass
of each spiked compound shall be 40 to 60 percent of the mass
expected to be collected with the unspiked train. Sample the stack
gas into the two trains simultaneously. Analyze the adsorbents from
the two trains utilizing identical analytical procedures and
instrumentation. Determine the fraction of spiked compound
recovered (R) using the equations in section 12.9.
8.4.3.1 Repeat the procedure in section 8.4.3 twice more, for a
total of three runs. In order for the adsorbent tube sampling and
analytical procedure to be acceptable for a compound, 0.70≤R≤1.30
(R in this case is the average of three runs). If the average R
value does not meet this criterion for a target compound, the
sampling technique is not acceptable for that compound, and
therefore another sampling technique shall be evaluated for
acceptance (by repeating the recovery study with another sampling
technique). Report the R value in the test report and correct all
field measurements with the calculated R value for that compound by
using the equation in section 12.8.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures
Section
Quality control measure
Effect
8.4.1
Recovery study for direct
interface or dilution interface sampling
Ensure that there are no
significant leaks in the sampling system.
8.4.2
Recovery study for bag
sampling
Demonstrate that proper
sampling/analysis procedures were selected.
8.4.3
Recovery study for adsorption
tube sampling
Demonstrate that proper
sampling/analysis procedures were selected.
10.0 Calibration and Standardization.
10.1 Calibration Standards. Obtain calibration gas standards for
each target compound to be analyzed. Commercial cylinder gases
certified by the manufacturer to be accurate to within 1 percent of
the certified label value are preferable, although cylinder gases
certified by the manufacturer to 2 percent accuracy are allowed.
Another option allowed by this method is for the tester to obtain
high concentration certified cylinder gases and then use a dilution
system meeting the requirements of Test Method 205, 40 CFR Part 51,
Appendix M to make multi-level calibration gas standards. Prepare
or obtain enough calibration standards so that there are three
different concentrations of each organic compound expected to be
measured in the source sample. For each organic compound, select
those concentrations that bracket the concentrations expected in
the source samples. A calibration standard may contain more than
one organic compound. If samples are collected in adsorbent tubes
and extracted using solvent extraction, prepare or obtain standards
in the same solvent used for the sample extraction procedure.
Verify the stability of all standards for the time periods they are
used.
10.2 Preparation of Calibration Curves.
10.2.1 Establish proper GC conditions, then flush the sampling
loop for 30 seconds. Allow the sample loop pressure to equilibrate
to atmospheric pressure, and activate the injection valve. Record
the standard concentration, attenuator factor, injection time,
chart speed, retention time, peak area, sample loop temperature,
column temperature, and carrier gas flow rate. Analyze each
standard in triplicate.
10.2.2 Repeat this procedure for each standard. Prepare a
graphical plot of concentration (Cs) versus the calibration area
values. Perform a regression analysis, and draw the least square
line.
11.0 Analytical Procedures
11.1 Analysis Development
11.1.1 Selection of GC Parameters
11.1.1.1 Column Choice. Based on the initial contact with plant
personnel concerning the plant process and the anticipated
emissions, choose a column that provides good resolution and rapid
analysis time. The choice of an appropriate column can be aided by
a literature search, contact with manufacturers of GC columns, and
discussion with personnel at the emission source.
Note:
Most column manufacturers keep excellent records on their
products. Their technical service departments may be able to
recommend appropriate columns and detector type for separating the
anticipated compounds, and they may be able to provide information
on interferences, optimum operating conditions, and column
limitations. Plants with analytical laboratories may be able to
provide information on their analytical procedures.
11.1.1.2 Preliminary GC Adjustment. Using the standards and
column obtained in section 11.1.1.1, perform initial tests to
determine appropriate GC conditions that provide good resolution
and minimum analysis time for the compounds of interest.
11.1.1.3 Preparation of Presurvey Samples. If the samples were
collected on an adsorbent, extract the sample as recommended by the
manufacturer for removal of the compounds with a solvent suitable
to the type of GC analysis. Prepare other samples in an appropriate
manner.
11.1.1.4 Presurvey Sample Analysis.
11.1.1.4.1 Before analysis, heat the presurvey sample to the
duct temperature to vaporize any condensed material. Analyze the
samples by the GC procedure, and compare the retention times
against those of the calibration samples that contain the
components expected to be in the stream. If any compounds cannot be
identified with certainty by this procedure, identify them by other
means such as GC/mass spectroscopy (GC/MS) or GC/infrared
techniques. A GC/MS system is recommended.
11.1.1.4.2 Use the GC conditions determined by the procedure of
section 11.1.1.2 for the first injection. Vary the GC parameters
during subsequent injections to determine the optimum settings.
Once the optimum settings have been determined, perform repeat
injections of the sample to determine the retention time of each
compound. To inject a sample, draw sample through the loop at a
constant rate (100 ml/min for 30 seconds). Be careful not to
pressurize the gas in the loop. Turn off the pump and allow the gas
in the sample loop to come to ambient pressure. Activate the sample
valve, and record injection time, loop temperature, column
temperature, carrier flow rate, chart speed, and attenuator
setting. Calculate the retention time of each peak using the
distance from injection to the peak maximum divided by the chart
speed. Retention times should be repeatable within 0.5 seconds.
11.1.1.4.3 If the concentrations are too high for appropriate
detector response, a smaller sample loop or dilutions may be used
for gas samples, and, for liquid samples, dilution with solvent is
appropriate. Use the standard curves (Section 10.2) to obtain an
estimate of the concentrations.
11.1.1.4.4 Identify all peaks by comparing the known retention
times of compounds expected to be in the retention times of peaks
in the sample. Identify any remaining unidentified peaks which have
areas larger than 5 percent of the total using a GC/MS, or
estimation of possible compounds by their retention times compared
to known compounds, with confirmation by further GC analysis.
12.0 Data Analysis and Calculations
12.1 Nomenclature.
Bws = Water vapor content of the bag sample or stack gas,
proportion by volume. Cs = Concentration of the organic from the
calibration curve, ppm. Gv = Gas volume or organic compound
injected, ml. Lv = Liquid volume of organic injected, µl. M =
Molecular weight of organic, g/g-mole. ms = Total mass of compound
measured on adsorbent with spiked train (µg). mu = Total mass of
compound measured on adsorbent with unspiked train (µg). mv = Mass
per volume of spiked compound measured (µg/L). Pi = Barometric or
absolute sample loop pressure at time of sample analysis, mm Hg. Pm
= Absolute pressure of dry gas meter, mm Hg. Pr = Reference
pressure, the barometric pressure or absolute sample loop pressure
recorded during calibration, mm Hg. Ps = Absolute pressure of
syringe before injection, mm Hg. qc = Flow rate of the calibration
gas to be diluted. qc1 = Flow rate of the calibration gas to be
diluted in stage 1. qc2 = Flow rate of the calibration gas to be
diluted in stage 2. qd = Diluent gas flow rate. qd1 = Flow rate of
diluent gas in stage 1. qd2 = Flow rate of diluent gas in stage 2.
s = Theoretical concentration (ppm) of spiked target compound in
the bag. S = Theoretical mass of compound spiked onto adsorbent in
spiked train (µg). t = Measured average concentration (ppm) of
target compound and source sample (analysis results subsequent to
bag spiking) Ti = Sample loop temperature at the time of sample
analysis, °K. Tm = Absolute temperature of dry gas meter, °K. Ts =
Absolute temperature of syringe before injection, °K. u = Source
sample average concentration (ppm) of target compound in the bag
(analysis results before bag spiking). Vm = Gas volume indicated by
dry gas meter, liters. vs = volume of stack gas sampled with spiked
train (L). vu = volume of stack gas sampled with unspiked train
(L). X = Mole or volume fraction of the organic in the calibration
gas to be diluted. Y = Dry gas meter calibration factor,
dimensionless. µl = Liquid organic density as determined, g/ml.
24.055 = Ideal gas molar volume at 293 °K and 760 mm Hg,
liters/g-mole. 1000 = Conversion factor, ml/liter. 10 6 =
Conversion to ppm.
12.2 Calculate the concentration, Cs, in ppm using the following
equation:
12.3 Calculate the concentration, Cs, in ppm of the organic in
the final gas mixture using the following equation:
12.4 Calculate each organic standard concentration, Cs, in ppm
using the following equation:
12.5 Calculate each organic standard concentration, Cs, in ppm
using the following equation:
12.6 Calculate the concentration, Cc, in ppm, dry basis, of each
organic is the sample using the following equation:
12.7 Calculate the average fraction recovered (R) of each spiked
target compound using the following equation:
12.8 Correct all field measurements with the calculated R value
for that compound using the following equation:
12.9 Determine the mass per volume of spiked compound measured
using the following equation:
12.10 Calculate the fraction of spiked compound recovered, R,
using the following equation:
13.0 Method Performance
13.1 Since a potential sample may contain a variety of compounds
from various sources, a specific precision limit for the analysis
of field samples is impractical. Precision in the range of 5 to 10
percent relative standard deviation (RSD) is typical for gas
chromatographic techniques, but an experienced GC operator with a
reliable instrument can readily achieve 5 percent RSD. For this
method, the following combined GC/operator values are required.
(a) Precision. Triplicate analyses of calibration standards fall
within 5 percent of their mean value.
(b) Recovery. After developing an appropriate sampling and
analytical system for the pollutants of interest, conduct the
procedure in section 8.4. Conduct the appropriate recovery study in
section 8.4 at each sampling point where the method is being
applied. Submit the data and results of the recovery procedure with
the reporting of results under section 8.3.
Presurvey screening is optional. Presurvey sampling should be
conducted for sources where the target pollutants are not known
from previous tests and/or process knowledge.
Perform a presurvey for each source to be tested. Refer to
Figure 18-1. Some of the information can be collected from
literature surveys and source personnel. Collect gas samples that
can be analyzed to confirm the identities and approximate
concentrations of the organic emissions.
16.1.1 Apparatus. This apparatus list also applies to sections
8.2 and 11.
16.1.1.1 Teflon Tubing. (Mention of trade names or specific
products does not constitute endorsement by the U.S. Environmental
Protection Agency.) Diameter and length determined by connection
requirements of cylinder regulators and the GC. Additional tubing
is necessary to connect the GC sample loop to the sample.
16.1.1.2 Gas Chromatograph. GC with suitable detector, columns,
temperature-controlled sample loop and valve assembly, and
temperature programmable oven, if necessary. The GC shall achieve
sensitivity requirements for the compounds under study.
16.1.1.3 Pump. Capable of pumping 100 ml/min. For flushing
sample loop.
16.1.1.4 Flow Meter. To measure flow rates.
16.1.1.5 Regulators. Used on gas cylinders for GC and for
cylinder standards.
16.1.1.6 Recorder. Recorder with linear strip chart is minimum
acceptable. Integrator (optional) is recommended.
16.1.1.7 Syringes. 0.5-ml, 1.0- and 10-microliter size,
calibrated, maximum accuracy (gas tight) for preparing calibration
standards. Other appropriate sizes can be used.
16.1.1.8 Tubing Fittings. To plumb GC and gas cylinders.
16.1.1.9 Septa. For syringe injections.
16.1.1.10 Glass Jars. If necessary, clean, colored glass jars
with Teflon-lined lids for condensate sample collection. Size
depends on volume of condensate.
16.1.1.11 Soap Film Flowmeter. To determine flow rates.
16.1.1.12 Flexible Bags. Tedlar or equivalent, 10- and 50-liter
capacity, for preparation of standards. (Verify through the
manufacturer that the Tedlar alternative is suitable for the
compound of interest and make this verifying information available
for inspection.)
16.1.1.13 Dry Gas Meter with Temperature and Pressure Gauges.
Accurate to ±2 percent, for preparation of gas standards.
16.1.1.14 Midget Impinger/Hot Plate Assembly. For preparation of
gas standards.
16.1.1.15 Sample Flasks. For presurvey samples, must have
gas-tight seals.
16.1.1.16 Adsorption Tubes. If necessary, blank tubes filled
with necessary adsorbent (charcoal, Tenax, XAD-2, etc.) for
presurvey samples.
16.1.1.18 Dilution System. Calibrated, the dilution system is to
be constructed following the specifications of an acceptable
method.
16.1.1.19 Sample Probes. Pyrex or stainless steel, of sufficient
length to reach centroid of stack, or a point no closer to the
walls than 1 m.
16.1.1.20 Barometer. To measure barometric pressure.
16.1.2 Reagents.
16.1.2.1 Water. Deionized distilled.
16.1.2.2 Methylene chloride.
16.1.2.3 Calibration Gases. A series of standards prepared for
every compound of interest.
16.1.2.4 Organic Compound Solutions. Pure (99.9 percent), or as
pure as can reasonably be obtained, liquid samples of all the
organic compounds needed to prepare calibration standards.
16.1.2.5 Extraction Solvents. For extraction of adsorbent tube
samples in preparation for analysis.
16.1.2.6 Fuel. As recommended by the manufacturer for operation
of the GC.
16.1.2.7 Carrier Gas. Hydrocarbon free, as recommended by the
manufacturer for operation of the detector and compatibility with
the column.
16.1.2.8 Zero Gas. Hydrocarbon free air or nitrogen, to be used
for dilutions, blank preparation, and standard preparation.
16.1.3 Sampling.
16.1.3.1 Collection of Samples with Glass Sampling Flasks.
Presurvey samples may be collected in precleaned 250-ml
double-ended glass sampling flasks. Teflon stopcocks, without
grease, are preferred. Flasks should be cleaned as follows: Remove
the stopcocks from both ends of the flasks, and wipe the parts to
remove any grease. Clean the stopcocks, barrels, and receivers with
methylene chloride (or other non-target pollutant solvent, or heat
and humidified air). Clean all glass ports with a soap solution,
then rinse with tap and deionized distilled water. Place the flask
in a cool glass annealing furnace, and apply heat up to 500 °C.
Maintain at this temperature for 1 hour. After this time period,
shut off and open the furnace to allow the flask to cool. Return
the stopcocks to the flask receivers. Purge the assembly with
high-purity nitrogen for 2 to 5 minutes. Close off the stopcocks
after purging to maintain a slight positive nitrogen pressure.
Secure the stopcocks with tape. Presurvey samples can be obtained
either by drawing the gases into the previously evacuated flask or
by drawing the gases into and purging the flask with a rubber
suction bulb.
16.1.3.1.1 Evacuated Flask Procedure. Use a high-vacuum pump to
evacuate the flask to the capacity of the pump; then close off the
stopcock leading to the pump. Attach a 6-mm outside diameter (OD)
glass tee to the flask inlet with a short piece of Teflon tubing.
Select a 6-mm OD borosilicate sampling probe, enlarged at one end
to a 12-mm OD and of sufficient length to reach the centroid of the
duct to be sampled. Insert a glass wool plug in the enlarged end of
the probe to remove particulate matter. Attach the other end of the
probe to the tee with a short piece of Teflon tubing. Connect a
rubber suction bulb to the third leg of the tee. Place the filter
end of the probe at the centroid of the duct, and purge the probe
with the rubber suction bulb. After the probe is completely purged
and filled with duct gases, open the stopcock to the grab flask
until the pressure in the flask reaches duct pressure. Close off
the stopcock, and remove the probe from the duct. Remove the tee
from the flask and tape the stopcocks to prevent leaks during
shipment. Measure and record the duct temperature and pressure.
16.1.3.1.2 Purged Flask Procedure. Attach one end of the
sampling flask to a rubber suction bulb. Attach the other end to a
6-mm OD glass probe as described in section 8.3.3.1.1. Place the
filter end of the probe at the centroid of the duct, or at a point
no closer to the walls than 1 m, and apply suction with the bulb to
completely purge the probe and flask. After the flask has been
purged, close off the stopcock near the suction bulb, and then
close off the stopcock near the probe. Remove the probe from the
duct, and disconnect both the probe and suction bulb. Tape the
stopcocks to prevent leakage during shipment. Measure and record
the duct temperature and pressure.
16.1.3.2 Flexible Bag Procedure. Any leak-free plastic (e.g.,
Tedlar, Mylar, Teflon) or plastic-coated aluminum (e.g., aluminized
Mylar) bag, or equivalent, can be used to obtain the pre-survey
sample. Use new bags, and leak-check them before field use. In
addition, check the bag before use for contamination by filling it
with nitrogen or air and analyzing the gas by GC at high
sensitivity. Experience indicates that it is desirable to allow the
inert gas to remain in the bag about 24 hours or longer to check
for desorption of organics from the bag. Follow the leak-check and
sample collection procedures given in Section 8.2.1.
16.1.3.3 Determination of Moisture Content. For combustion or
water-controlled processes, obtain the moisture content from plant
personnel or by measurement during the presurvey. If the source is
below 59 °C, measure the wet bulb and dry bulb temperatures, and
calculate the moisture content using a psychrometric chart. At
higher temperatures, use Method 4 to determine the moisture
content.
16.1.4 Determination of Static Pressure. Obtain the static
pressure from the plant personnel or measurement. If a type S pitot
tube and an inclined manometer are used, take care to align the
pitot tube 90° from the direction of the flow. Disconnect one of
the tubes to the manometer, and read the static pressure; note
whether the reading is positive or negative.
16.1.5 Collection of Presurvey Samples with Adsorption Tube.
Follow section 8.2.4 for presurvey sampling.
17.0 References
1. American Society for Testing and Materials. C1 Through C5
Hydrocarbons in the Atmosphere by Gas Chromatography. ASTM D
2820-72, Part 23. Philadelphia, Pa. 23:950-958. 1973.
2. Corazon, V.V. Methodology for Collecting and Analyzing
Organic Air Pollutants. U.S. Environmental Protection Agency.
Research Triangle Park, N.C. Publication No. EPA-600/2-79-042.
February 1979.
3. Dravnieks, A., B.K. Krotoszynski, J. Whitfield, A. O'Donnell,
and T. Burgwald. Environmental Science and Technology.
5(12):1200-1222. 1971.
4. Eggertsen, F.T., and F.M. Nelsen. Gas Chromatographic
Analysis of Engine Exhaust and Atmosphere. Analytical Chemistry.
30(6): 1040-1043. 1958.
5. Feairheller, W.R., P.J. Marn, D.H. Harris, and D.L. Harris.
Technical Manual for Process Sampling Strategies for Organic
Materials. U.S. Environmental Protection Agency. Research Triangle
Park, N.C. Publication No. EPA 600/2-76-122. April 1976. 172 p.
6. Federal Register, 39 FR 9319-9323. 1974.
7. Federal Register, 39 FR 32857-32860. 1974.
8. Federal Register, 23069-23072 and 23076-23090. 1976.
9. Federal Register, 46569-46571. 1976.
10. Federal Register, 41771-41776. 1977.
11. Fishbein, L. Chromatography of Environmental Hazards, Volume
II. Elesevier Scientific Publishing Company. New York, N.Y.
1973.
12. Hamersma, J.W., S.L. Reynolds, and R.F. Maddalone.
EPA/IERL-RTP Procedures Manual: Level 1 Environmental Assessment.
U.S. Environmental Protection Agency. Research Triangle Park, N.C.
Publication No. EPA 600/276-160a. June 1976. 130 p.
13. Harris, J.C., M.J. Hayes, P.L. Levins, and D.B. Lindsay.
EPA/IERL-RTP Procedures for Level 2 Sampling and Analysis of
Organic Materials. U.S. Environmental Protection Agency. Research
Triangle Park, N.C. Publication No. EPA 600/7-79-033. February
1979. 154 p.
14. Harris, W.E., H.W. Habgood. Programmed Temperature Gas
Chromatography. John Wiley and Sons, Inc. New York. 1966.
15. Intersociety Committee. Methods of Air Sampling and
Analysis. American Health Association. Washington, D.C. 1972.
16. Jones, P.W., R.D. Grammer, P.E. Strup, and T.B. Stanford.
Environmental Science and Technology. 10:806-810. 1976.
17. McNair Han Bunelli, E.J. Basic Gas Chromatography.
Consolidated Printers. Berkeley. 1969.
18. Nelson, G.O. Controlled Test Atmospheres, Principles and
Techniques. Ann Arbor. Ann Arbor Science Publishers. 1971. 247
p.
19. NIOSH Manual of Analytical Methods, Volumes 1, 2, 3, 4, 5,
6, 7. U.S. Department of Health and Human Services, National
Institute for Occupational Safety and Health. Center for Disease
Control. 4676 Columbia Parkway, Cincinnati, Ohio 45226. April 1977
- August 1981. May be available from the Superintendent of
Documents, Government Printing Office, Washington, D.C. 20402.
Stock Number/Price:
20. Schuetzle, D., T.J. Prater, and S.R. Ruddell. Sampling and
Analysis of Emissions from Stationary Sources; I. Odor and Total
Hydrocarbons. Journal of the Air Pollution Control Association.
25(9): 925-932. 1975.
21. Snyder, A.D., F.N. Hodgson, M.A. Kemmer and J.R. McKendree.
Utility of Solid Sorbents for Sampling Organic Emissions from
Stationary Sources. U.S. Environmental Protection Agency. Research
Triangle Park, N.C. Publication No. EPA 600/2-76-201. July 1976. 71
p.
22. Tentative Method for Continuous Analysis of Total
Hydrocarbons in the Atmosphere. Intersociety Committee, American
Public Health Association. Washington, D.C. 1972. p. 184-186.
23. Zwerg, G. CRC Handbook of Chromatography, Volumes I and II.
Sherma, Joseph (ed.). CRC Press. Cleveland. 1972.
18.0 Tables, Diagrams, Flowcharts, and Validation Data I. Name of
company Date Address Contracts Phone Process to be sampled Duct or
vent to be sampled II. Process description Raw material Products
Operating cycle Check: Batch ____ Continuous ____ Cyclic ____
Timing of batch or cycle Best time to test III. Sampling site A.
Description Site decription Duct shape and size Material Wall
thickness ____ inches Upstream distance ____ inches ____ diameter
Downstream distance ____ inches ____ diameter Size of port Size of
access area Hazards ____ Ambient temp. ____ °F B. Properties of gas
stream Temperature ____ °C ____ °F, Data source ____ Velocity ____,
Data source ____ Static pressure ____ inches H2O, Data source ____
Moisture content ____%, Data source ____ Particulate content ____,
Data source____ Gaseous components N2 ____ % Hydrocarbons ____ ppm
O2 ____% ____ CO ____ % ____ ____ CO2 ____ % ____ ____ SO2 ____ %
____ ____ Hydrocarbon components ____ ____ ppm ____ ____ ppm ____
____ ppm ____ ____ ppm ____ ____ ppm ____ ____ ppm C. Sampling
considerations Location to set up GC Special hazards to be
considered Power available at duct Power available for GC Plant
safety requirements Vehicle traffic rules Plant entry requirements
Security agreements Potential problems D. Site diagrams. (Attach
additional sheets if required). Figure 18-1. Preliminary Survey
Data Sheet Components to be analyzed and Expected
concentration Suggested chromatographic column Column flow rate
_ ml/min Head pressure ____ mm Hg Column temperature: Isothermal
____ °C, Programmed from ____ °C to ____ °C at ____ °C/min
Injection port/sample loop temperature ____ °C Detector temperature
____ °C Detector flow rates: Hydrogen ____ ml/min., head pressure
____ mm Hg, Air/Oxygen ____ ml/min., head pressure ____ mm Hg.
Chart speed ____ inches/minute Compound data: Compound and
Retention time and Attenuation Figure 18-2. Chromatographic
Conditions Data Sheet
Figure 18-3. Preparation of Standards in
Tedlar or Tedlar-Equlivalent Bags and Calibration Curve
Standards
Mixture #1
Mixture #2
Mixture #3
Standards
Preparation Data:
Organic:
Bag number or
identification
Dry gas meter
calibration factor
Final meter
reading (liters)
Initial meter
reading (liters)
Metered volume
(liters)
Average meter
temperature (°K)
Average meter
pressure, gauge (mm Hg)
Average
atmospheric perssure (mm Hg)
Average meter
pressure, absolute (mm Hg)
Syringe
temperature (°K) (see section 10.1.2.1)
Syringe
pressure, absolute (mm Hg) (see section 10.1.2.1)
Volume of gas
in syringe (ml) (Section 10.1.2.1)
Density of
liquid organic (g/ml) (Section 10.1.2.1)
Volume of
liquid in syringe (ml) (Section 10.1.2.1)
GC Operating
Conditions:
Sample loop
volume (ml)
Sample loop
temperature ( °C)
Carrier gas
flow rate (ml/min)
Column
temperature:
Initial (
°C)
Rate change (
°C/min)
Final (
°C)
Organic Peak
Identification and Calculated Concentrations:
Injection time
(24 hour clock)
Distance to
peak (cm)
Chart speed
(cm/min)
Organic
retention time (min)
Attenuation
factor
Peak height
(mm)
Peak area
(mm2)
Peak area *
attenuation factor (mm2)
Calculated
concentration (ppm) (Equation 18-3 or 18-4)
Plot peak area * attenuation factor against
calculated concentration to obtain calibration curve.
Flowmeter number or identification Flowmeter Type Method: Bubble
meter__ Spirometer__ Wet test meter __ Readings at laboratory
conditions: Laboratory temperature (Tlab) __ °K Laboratory
barometric pressure (Plab)__ mm Hg Flow data:
Flowmeter
Reading (as marked)
Temp. (°K)
Pressure (absolute)
Calibration Device
Time (min)
Gas volume a
Flow rate b
a Vol. of gas may be measured in
milliliters, liters or cubic feet.
b Convert to standard conditions
(20 °C and 760 mm Hg). Plot flowmeter reading against flow rate
(standard conditions), and draw a smooth curve. If the flowmeter
being calibrated is a rotameter or other flow device that is
viscosity dependent, it may be necessary to generate a “family” of
calibration curves that cover the operating pressure and
temperature ranges of the flowmeter. While the following technique
should be verified before application, it may be possible to
calculate flow rate reading for rotameters at standard conditions
Qstd as follows:
Flow rate (laboratory
conditions)
Flow rate (STD
conditions)
Figure 18-4. Flowmeter Calibration
Preparation of Standards by Dilution of
Cylinder Standard
Flow rate
cylinder gas at standard conditions (ml/min)
Flow rate
diluent gas at standard conditions (ml/min)
Calculated
concentration (ppm)
Stage 2 (if
used):
Standard gas
flowmeter reading
Diluent gas
flowmeter reading
Flow rate Stage
1 gas at standard conditions (ml/min)
Flow rate
diluent gas at standard conditions
Calculated
concentration (ppm)
GC Operating
Conditions:
Sample loop
volume (ml)
Sample loop
temperature ( °C)
Carrier gas
flow rate (ml/min)
Column
temperature:
Initial (
°C)
Program rate (
°C/min)
Final (
°C)
Organic Peak
Identification and Calculated Concentrations:
Injection time
(24-hour clock)
Distance to
peak (cm)
Chart speed
(cm/min)
Retention time
(min)
Attenuation
factor
Peak area (mm
2)
Peak area
*attenuation factor
Plot peak area *attenuation factor against
calculated concentration to obtain calibration curve.
Figure 18-7. Standards Prepared by Dilution of Cylinder Standard
Plant____ Date____ Site____
Sample 1
Sample 2
Sample 3
Source temperature
( °C)
Barometric
pressure (mm Hg)
Ambient
temperature ( °C)
Sample flow rate
(appr.)
Bag number
Start time
Finish time
Figure 18-10. Field Sample Data Sheet - Tedlar or Tedlar-Equivalent
Bag Collection Method
Plant _________ Date ________ Location
____________
1. General
information:
Source
temperature ( °C)
Probe
temperature ( °C)
Ambient
temperature ( °C)
Atmospheric
pressure (mm)
Source pressure
(′Hg)
Absolute source
pressure (mm)
Sampling rate
(liter/min)
Sample loop
volume (ml)
Sample loop
temperature ( °C)
Columnar
temperature:
Initial ( °C)
time (min)
Program rate (
°C/min)
Final (
°C)/time (min)
Carrier gas
flow rate (ml/min)
Detector
temperature ( °C)
Injection time
(24-hour basis)
Chart Speed
(mm/min)
Dilution gas
flow rate (ml/min)
Dilution gas
used (symbol)
Dilution
ratio
2. Field Analysis Data - Calibration
Gas
2. [Run No. ____ Time ______]
Components
Area
Attenuation
A × A Factor
Conc._ (ppm)
Figure 18-11. Field Analysis Data Sheets
Gaseous Organic Sampling and Analysis Check
List
[Respond with initials or number as
appropriate]
Date
1. Presurvey
data:
A. Grab sample
collected
□
___
B. Grab sample
analyzed for composition
□
___
Method GC
□
___
GC/MS
□
___
Other
□
___
C. GC-FID
analysis performed
□
___
2. Laboratory
calibration data:
A. Calibration
curves prepared
□
___
Number of
components
□
___
Number of
concentrations/component (3 required)
□
___
B. Audit
samples (optional):
Analysis
completed
□
___
Verified for
concentration
□
___
OK obtained for
field work
□
___
3. Sampling
procedures:
A. Method:
Bag sample
□
___
Direct
interface
□
___
Dilution
interface
□
___
B. Number of
samples collected
□
___
4. Field
Analysis:
A. Total
hydrocarbon analysis performed
□
___
B. Calibration
curve prepared
□
___
Number of
components
□
___
Number of
concentrations per component (3 required)
□
___
Gaseous Organic Sampling and Analysis Data Plant Date Location
Gaseous Organic Sampling and Analysis Check
List (Respond With Initials or Number as Appropriate)
1. Pre-survey
data
Date
A. Grab sample
collected
____
B. Grab sample
analyzed for composition
____
Method GC
____
GC/MS
____
Other____________
____
C. GC-FID
analysis performed
____
2. Laboratory
calibration curves prepared
____
A. Number of
components
____
B. Number of
concentrations per component (3 required)
____
C. OK obtained
for field work
____
3. Sampling
procedures
A. Method
Bag sample
____
Direct
interface
____
Dilution
interface
____
B. Number of
samples collected
____
4. Field
Analysis
A. Total
hydrocarbon analysis performed
____
B. Calibration
curve prepared
____
Number of
components
____
Number of
concentrations per component (3 required)
____
Figure 18-14. Sampling and Analysis Sheet [36 FR 24877, Dec. 23,
1971] Editorial Note:For Federal Register citations affecting
appendix A-6 to part 60, see the List of CFR sections Affected,
which appears in the Finding Aids section of the printed volume and
at www.govinfo.gov.
Appendix A-7 to Part 60 - Test Methods 19 through 25E
40:9.0.1.1.1.0.1.1.7 : Appendix A
Appendix A-7 to Part 60 - Test Methods 19 through 25E Method 19 -
Determination of sulfur dioxide removal efficiency and particulate,
sulfur dioxide and nitrogen oxides emission rates Method 20 -
Determination of nitrogen oxides, sulfur dioxide, and diluent
emissions from stationary gas turbines Method 21 - Determination of
volatile organic compound leaks Method 22 - Visual determination of
fugitive emissions from material sources and smoke emissions from
flares Method 23 - Determination of Polychlorinated
Dibenzo-p-Dioxins and Polychlorinated Dibenzofurans From Stationary
Sources Method 24 - Determination of volatile matter content, water
content, density, volume solids, and weight solids of surface
coatings Method 24A - Determination of volatile matter content and
density of printing inks and related coatings Method 25 -
Determination of total gaseous nonmethane organic emissions as
carbon Method 25A - Determination of total gaseous organic
concentration using a flame ionization analyzer Method 25B -
Determination of total gaseous organic concentration using a
nondispersive infrared analyzer Method 25C - Determination of
nonmethane organic compounds (NMOC) in MSW landfill gases Method
25D - Determination of the Volatile Organic Concentration of Waste
Samples Method 25E - Determination of Vapor Phase Organic
Concentration in Waste Samples
The test methods in this appendix are referred to in § 60.8
(Performance Tests) and § 60.11 (Compliance With Standards and
Maintenance Requirements) of 40 CFR part 60, subpart A (General
Provisions). Specific uses of these test methods are described in
the standards of performance contained in the subparts, beginning
with Subpart D.
Within each standard of performance, a section title “Test
Methods and Procedures” is provided to: (1) Identify the test
methods to be used as reference methods to the facility subject to
the respective standard and (2) identify any special instructions
or conditions to be followed when applying a method to the
respective facility. Such instructions (for example, establish
sampling rates, volumes, or temperatures) are to be used either in
addition to, or as a substitute for procedures in a test method.
Similarly, for sources subject to emission monitoring requirements,
specific instructions pertaining to any use of a test method as a
reference method are provided in the subpart or in Appendix B.
Inclusion of methods in this appendix is not intended as an
endorsement or denial of their applicability to sources that are
not subject to standards of performance. The methods are
potentially applicable to other sources; however, applicability
should be confirmed by careful and appropriate evaluation of the
conditions prevalent at such sources.
The approach followed in the formulation of the test methods
involves specifications for equipment, procedures, and performance.
In concept, a performance specification approach would be
preferable in all methods because this allows the greatest
flexibility to the user. In practice, however, this approach is
impractical in most cases because performance specifications cannot
be established. Most of the methods described herein, therefore,
involve specific equipment specifications and procedures, and only
a few methods in this appendix rely on performance criteria.
Minor changes in the test methods should not necessarily affect
the validity of the results and it is recognized that alternative
and equivalent methods exist. section 60.8 provides authority for
the Administrator to specify or approve (1) equivalent methods, (2)
alternative methods, and (3) minor changes in the methodology of
the test methods. It should be clearly understood that unless
otherwise identified all such methods and changes must have prior
approval of the Administrator. An owner employing such methods or
deviations from the test methods without obtaining prior approval
does so at the risk of subsequent disapproval and retesting with
approved methods.
Within the test methods, certain specific equipment or
procedures are recognized as being acceptable or potentially
acceptable and are specifically identified in the methods. The
items identified as acceptable options may be used without approval
but must be identified in the test report. The potentially
approvable options are cited as “subject to the approval of the
Administrator” or as “or equivalent.” Such potentially approvable
techniques or alternatives may be used at the discretion of the
owner without prior approval. However, detailed descriptions for
applying these potentially approvable techniques or alternatives
are not provided in the test methods. Also, the potentially
approvable options are not necessarily acceptable in all
applications. Therefore, an owner electing to use such potentially
approvable techniques or alternatives is responsible for: (1)
assuring that the techniques or alternatives are in fact applicable
and are properly executed; (2) including a written description of
the alternative method in the test report (the written method must
be clear and must be capable of being performed without additional
instruction, and the degree of detail should be similar to the
detail contained in the test methods); and (3) providing any
rationale or supporting data necessary to show the validity of the
alternative in the particular application. Failure to meet these
requirements can result in the Administrator's disapproval of the
alternative.
Method 19 - Determination of Sulfur Dioxide Removal Efficiency and
Particulate Matter, Sulfur Dioxide, and Nitrogen Oxide Emission
Rates 1.0 Scope and Application
1.1 Analytes. This method provides data reduction procedures
relating to the following pollutants, but does not include any
sample collection or analysis procedures.
Analyte
CAS No.
Sensitivity
Nitrogen oxides
(NOX), including:
Nitric oxide
(NO)
10102-43-9
N/A
Nitrogen
dioxide (NO2)
10102-44-0
Particulate matter
(PM)
None assigned
N/A
Sulfur dioxide
(SO2)
7499-09-05
N/A
1.2 Applicability. Where specified by an applicable subpart of
the regulations, this method is applicable for the determination of
(a) PM, SO2, and NOX emission rates; (b) sulfur removal
efficiencies of fuel pretreatment and SO2 control devices; and (c)
overall reduction of potential SO2 emissions.
2.0 Summary of Method
2.1 Emission Rates. Oxygen (O2) or carbon dioxide (CO2)
concentrations and appropriate F factors (ratios of combustion gas
volumes to heat inputs) are used to calculate pollutant emission
rates from pollutant concentrations.
2.2 Sulfur Reduction Efficiency and SO2 Removal Efficiency. An
overall SO2 emission reduction efficiency is computed from the
efficiency of fuel pretreatment systems, where applicable, and the
efficiency of SO2 control devices.
2.2.1 The sulfur removal efficiency of a fuel pretreatment
system is determined by fuel sampling and analysis of the sulfur
and heat contents of the fuel before and after the pretreatment
system.
2.2.2 The SO2 removal efficiency of a control device is
determined by measuring the SO2 rates before and after the control
device.
2.2.2.1 The inlet rates to SO2 control systems (or, when SO2
control systems are not used, SO2 emission rates to the atmosphere)
are determined by fuel sampling and analysis.
3.0 Definitions [Reserved] 4.0 Interferences [Reserved] 5.0 Safety
[Reserved] 6.0 Equipment and Supplies [Reserved] 7.0 Reagents and
Standards [Reserved] 8.0 Sample Collection, Preservation, Storage,
and Transport [Reserved] 9.0 Quality Control [Reserved] 10.0
Calibration and Standardization [Reserved] 11.0 Analytical
Procedures [Reserved] 12.0 Data Analysis and Calculations
12.1 Nomenclature
Bwa = Moisture fraction of ambient air, percent. Bws = Moisture
fraction of effluent gas, percent. %C = Concentration of carbon
from an ultimate analysis of fuel, weight percent. Cd = Pollutant
concentration, dry basis, ng/scm (lb/scf) %CO2d,%CO2w =
Concentration of carbon dioxide on a dry and wet basis,
respectively, percent. Cw = Pollutant concentration, wet basis,
ng/scm (lb/scf). D = Number of sampling periods during the
performance test period. E = Pollutant emission rate, ng/J
(lb/million Btu). Ea = Average pollutant rate for the specified
performance test period, ng/J (lb/million Btu). Eao, Eai = Average
pollutant rate of the control device, outlet and inlet,
respectively, for the performance test period, ng/J (lb/million
Btu). Ebi = Pollutant rate from the steam generating unit, ng/J
(lb/million Btu) Ebo = Pollutant emission rate from the steam
generating unit, ng/J (lb/million Btu). Eci = Pollutant rate in
combined effluent, ng/J (lb/million Btu). Eco = Pollutant emission
rate in combined effluent, ng/J (lb/million Btu). Ed = Average
pollutant rate for each sampling period (e.g., 24-hr Method
6B sample or 24-hr fuel sample) or for each fuel lot (e.g.,
amount of fuel bunkered), ng/J (lb/million Btu). Edi = Average
inlet SO2 rate for each sampling period d, ng/J (lb/million Btu) Eg
= Pollutant rate from gas turbine, ng/J (lb/million Btu). Ega =
Daily geometric average pollutant rate, ng/J (lbs/million Btu) or
ppm corrected to 7 percent O2. Ejo,Eji = Matched pair hourly
arithmetic average pollutant rate, outlet and inlet, respectively,
ng/J (lb/million Btu) or ppm corrected to 7 percent O2. Eh = Hourly
average pollutant, ng/J (lb/million Btu). Ehj = Hourly arithmetic
average pollutant rate for hour “j,” ng/J (lb/million Btu) or ppm
corrected to 7 percent O2. EXP = Natural logarithmic base (2.718)
raised to the value enclosed by brackets. Fd, Fw, Fc = Volumes of
combustion components per unit of heat content, scm/J (scf/million
Btu). GCV = Gross calorific value of the fuel consistent with the
ultimate analysis, kJ/kg (Btu/lb). GCVp, GCVr = Gross calorific
value for the product and raw fuel lots, respectively, dry basis,
kJ/kg (Btu/lb). %H = Concentration of hydrogen from an ultimate
analysis of fuel, weight percent. H = Total number of operating
hours for which pollutant rates are determined in the performance
test period. Hb = Heat input rate to the steam generating unit from
fuels fired in the steam generating unit, J/hr (million Btu/hr). Hg
= Heat input rate to gas turbine from all fuels fired in the gas
turbine, J/hr (million Btu/hr). %H2O = Concentration of water from
an ultimate analysis of fuel, weight percent. Hr = Total numbers of
hours in the performance test period (e.g., 720 hours for
30-day performance test period). K = Conversion factor, 10−5
(kJ/J)/(%) [106 Btu/million Btu]. Kc = (9.57 scm/kg)/% [(1.53
scf/lb)/%]. Kcc = (2.0 scm/kg)/% [(0.321 scf/lb)/%]. Khd = (22.7
scm/kg)/% [(3.64 scf/lb)/%]. Khw = (34.74 scm/kg)/% [(5.57
scf/lb)/%]. Kn = (0.86 scm/kg)/% [(0.14 scf/lb)/%]. Ko = (2.85
scm/kg)/% [(0.46 scf/lb)/%]. Ks = (3.54 scm/kg)/% [(0.57
scf/lb)/%]. Kw = (1.30 scm/kg)/% [(0.21 scf/lb)/%]. ln = Natural
log of indicated value. Lp,Lr = Weight of the product and raw fuel
lots, respectively, metric ton (ton). %N = Concentration of
nitrogen from an ultimate analysis of fuel, weight percent. N =
Number of fuel lots during the averaging period. n = Number of
fuels being burned in combination. nd = Number of operating hours
of the affected facility within the performance test period for
each Ed determined. nt = Total number of hourly averages for which
paired inlet and outlet pollutant rates are available within the
24-hr midnight to midnight daily period. %O = Concentration of
oxygen from an ultimate analysis of fuel, weight percent. %O2d,
%O2w = Concentration of oxygen on a dry and wet basis,
respectively, percent. Ps = Potential SO2 emissions, percent. %Rf =
SO2 removal efficiency from fuel pretreatment, percent. %Rg = SO2
removal efficiency of the control device, percent. %Rga = Daily
geometric average percent reduction. %Ro = Overall SO2 reduction,
percent. %S = Sulfur content of as-fired fuel lot, dry basis,
weight percent. Se = Standard deviation of the hourly average
pollutant rates for each performance test period, ng/J (lb/million
Btu). %Sf = Concentration of sulfur from an ultimate analysis of
fuel, weight percent. Si = Standard deviation of the hourly average
inlet pollutant rates for each performance test period, ng/J
(lb/million Btu). So = Standard deviation of the hourly average
emission rates for each performance test period, ng/J (lb/million
Btu). %Sp, %Sr = Sulfur content of the product and raw fuel lots
respectively, dry basis, weight percent. t0.95 = Values shown in
Table 19-3 for the indicated number of data points n. Xk = Fraction
of total heat input from each type of fuel k.
12.2 Emission Rates of PM, SO2, and NOX. Select from the
following sections the applicable procedure to compute the PM, SO2,
or NOX emission rate (E) in ng/J (lb/million Btu). The pollutant
concentration must be in ng/scm (lb/scf) and the F factor must be
in scm/J (scf/million Btu). If the pollutant concentration (C) is
not in the appropriate units, use Table 19-1 in section 17.0 to
make the proper conversion. An F factor is the ratio of the gas
volume of the products of combustion to the heat content of the
fuel. The dry F factor (Fd) includes all components of combustion
less water, the wet F factor (Fw) includes all components of
combustion, and the carbon F factor (Fc) includes only carbon
dioxide.
Note:
Since Fw factors include water resulting only from the
combustion of hydrogen in the fuel, the procedures using Fw factors
are not applicable for computing E from steam generating units with
wet scrubbers or with other processes that add water (e.g.,
steam injection).
12.2.1 Oxygen-Based F Factor, Dry Basis. When measurements are
on a dry basis for both O (%O2d) and pollutant (Cd) concentrations,
use the following equation:
12.2.2 Oxygen-Based F Factor, Wet Basis. When measurements are
on a wet basis for both O2 (%O2w) and pollutant (Cw)
concentrations, use either of the following:
12.2.2.1 If the moisture fraction of ambient air (Bwa) is
measured:
Instead of actual measurement, Bwa may be estimated according to
the procedure below.
Note:
The estimates are selected to ensure that negative errors will
not be larger than −1.5 percent. However, positive errors, or
over-estimation of emissions by as much as 5 percent may be
introduced depending upon the geographic location of the facility
and the associated range of ambient moisture.
12.2.2.1.1 Bwa = 0.027. This value may be used at any location
at all times.
12.2.2.1.2 Bwa = Highest monthly average of Bwa that occurred
within the previous calendar year at the nearest Weather Service
Station. This value shall be determined annually and may be used as
an estimate for the entire current calendar year.
12.2.2.1.3 Bwa = Highest daily average of Bwa that occurred
within a calendar month at the nearest Weather Service Station,
calculated from the data from the past 3 years. This value shall be
computed for each month and may be used as an estimate for the
current respective calendar month.
12.2.2.2 If the moisture fraction (Bws) of the effluent gas is
measured:
12.2.3 Oxygen-Based F Factor, Dry/Wet Basis.
12.2.3.1 When the pollutant concentration is measured on a wet
basis (Cw) and O2 concentration is measured on a dry basis (%O2d),
use the following equation:
12.2.3.2 When the pollutant concentration is measured on a dry
basis (Cd) and the O2 concentration is measured on a wet basis
(%O2w), use the following equation:
12.2.4 Carbon Dioxide-Based F Factor, Dry Basis. When
measurements are on a dry basis for both CO2 (%CO2d) and pollutant
(Cd) concentrations, use the following equation:
12.2.5 Carbon Dioxide-Based F Factor, Wet Basis. When
measurements are on a wet basis for both CO2 (%CO2w) and pollutant
(Cw) concentrations, use the following equation:
12.2.6 Carbon Dioxide-Based F Factor, Dry/Wet Basis.
12.2.6.1 When the pollutant concentration is measured on a wet
basis (Cw) and CO2 concentration is measured on a dry basis
(%CO2d), use the following equation:
12.2.6.2 When the pollutant concentration is measured on a dry
basis (Cd) and CO2 concentration is measured on a wet basis
(%CO2w), use the following equation:
12.2.7 Direct-Fired Reheat Fuel Burning. The effect of
direct-fired reheat fuel burning (for the purpose of raising the
temperature of the exhaust effluent from wet scrubbers to above the
moisture dew-point) on emission rates will be less than 1.0 percent
and, therefore, may be ignored.
12.2.8 Combined Cycle-Gas Turbine Systems. For gas turbine-steam
generator combined cycle systems, determine the emissions from the
steam generating unit or the percent reduction in potential SO2
emissions as follows:
12.2.8.1 Compute the emission rate from the steam generating
unit using the following equation:
12.2.8.1.1 Use the test methods and procedures section of 40 CFR
Part 60, Subpart GG to obtain Eco and Eg. Do not use Fw factors for
determining Eg or Eco. If an SO2 control device is used, measure
Eco after the control device.
12.2.8.1.2 Suitable methods shall be used to determine the heat
input rates to the steam generating units (Hb) and the gas turbine
(Hg).
12.2.8.2 If a control device is used, compute the percent of
potential SO2 emissions (Ps) using the following equations:
Note:
Use the test methods and procedures section of Subpart GG to
obtain Eci and Eg. Do not use Fw factors for determining Eg or
Eci.
12.3 F Factors. Use an average F factor according to section
12.3.1 or determine an applicable F factor according to section
12.3.2. If combined fuels are fired, prorate the applicable F
factors using the procedure in section 12.3.3.
12.3.1 Average F Factors. Average F factors (Fd, Fw, or Fc) from
Table 19-2 in section 17.0 may be used.
12.3.2 Determined F Factors. If the fuel burned is not listed in
Table 19-2 or if the owner or operator chooses to determine an F
factor rather than use the values in Table 19-2, use the procedure
below:
12.3.2.1 Equations. Use the equations below, as appropriate, to
compute the F factors:
Note:
Omit the %H2O term in the equations for Fw if %H and %O include
the unavailable hydrogen and oxygen in the form of H2O.)
12.3.2.2 Use applicable sampling procedures in section 12.5.2.1
or 12.5.2.2 to obtain samples for analyses.
12.3.2.3 Use ASTM D 3176-74 or 89 (all cited ASTM standards are
incorporated by reference - see § 60.17) for ultimate analysis of
the fuel.
12.3.2.4 Use applicable methods in section 12.5.2.1 or 12.5.2.2
to determine the heat content of solid or liquid fuels. For gaseous
fuels, use ASTM D 1826-77 or 94 (incorporated by reference - see §
60.17) to determine the heat content.
12.3.3 F Factors for Combination of Fuels. If combinations of
fuels are burned, use the following equations, as applicable unless
otherwise specified in an applicable subpart:
12.4 Determination of Average Pollutant Rates.
12.4.1 Average Pollutant Rates from Hourly Values. When hourly
average pollutant rates (Eh), inlet or outlet, are obtained
(e.g., CEMS values), compute the average pollutant rate (Ea)
for the performance test period (e.g., 30 days) specified in
the applicable regulation using the following equation:
12.4.2 Average Pollutant Rates from Other than Hourly Averages.
When pollutant rates are determined from measured values
representing longer than 1-hour periods (e.g., daily fuel
sampling and analyses or Method 6B values), or when pollutant rates
are determined from combinations of 1-hour and longer than 1-hour
periods (e.g., CEMS and Method 6B values), compute the
average pollutant rate (Ea) for the performance test period
(e.g., 30 days) specified in the applicable regulation using
the following equation:
12.4.3 Daily Geometric Average Pollutant Rates from Hourly
Values. The geometric average pollutant rate (Ega) is computed
using the following equation:
12.5 Determination of Overall Reduction in Potential Sulfur
Dioxide Emission.
12.5.1 Overall Percent Reduction. Compute the overall percent
SO2 reduction (%Ro) using the following equation:
12.5.2 Pretreatment Removal Efficiency (Optional). Compute the
SO2 removal efficiency from fuel pretreatment (%Rf) for the
averaging period (e.g., 90 days) as specified in the
applicable regulation using the following equation:
Note:
In calculating %Rf, include %S and GCV values for all fuel lots
that are not pretreated and are used during the averaging
period.
12.5.2.1 Solid Fossil (Including Waste) Fuel/Sampling and
Analysis.
Note:
For the purposes of this method, raw fuel (coal or oil) is the
fuel delivered to the desulfurization (pretreatment) facility. For
oil, the input oil to the oil desulfurization process (e.g.,
hydrotreatment) is considered to be the raw fuel.
12.5.2.1.1 Sample Increment Collection. Use ASTM D 2234-76, 96,
97a, or 98 (incorporated by reference - see § 60.17), Type I,
Conditions A, B, or C, and systematic spacing. As used in this
method, systematic spacing is intended to include evenly spaced
increments in time or increments based on equal weights of coal
passing the collection area. As a minimum, determine the number and
weight of increments required per gross sample representing each
coal lot according to Table 2 or Paragraph 7.1.5.2 of ASTM D 2234.
Collect one gross sample for each lot of raw coal and one gross
sample for each lot of product coal.
12.5.2.1.2 ASTM Lot Size. For the purpose of section 12.5.2
(fuel pretreatment), the lot size of product coal is the weight of
product coal from one type of raw coal. The lot size of raw coal is
the weight of raw coal used to produce one lot of product coal.
Typically, the lot size is the weight of coal processed in a 1-day
(24-hour) period. If more than one type of coal is treated and
produced in 1 day, then gross samples must be collected and
analyzed for each type of coal. A coal lot size equaling the 90-day
quarterly fuel quantity for a steam generating unit may be used if
representative sampling can be conducted for each raw coal and
product coal.
Note:
Alternative definitions of lot sizes may be used, subject to
prior approval of the Administrator.
12.5.2.1.3 Gross Sample Analysis. Use ASTM D 2013-72 or 86 to
prepare the sample, ASTM D 3177-75 or 89 or ASTM D 4239-85, 94, or
97 to determine sulfur content (%S), ASTM D 3173-73 or 87 to
determine moisture content, and ASTM D 2015-77 (Reapproved 1978) or
96, D 3286-85 or 96, or D 5865-98 or 10 to determine gross
calorific value (GCV) (all standards cited are incorporated by
reference - see § 60.17 for acceptable versions of the standards)
on a dry basis for each gross sample.
12.5.2.2 Liquid Fossil Fuel-Sampling and Analysis. See Note
under section 12.5.2.1.
12.5.2.2.1 Sample Collection. Follow the procedures for
continuous sampling in ASTM D 270 or D 4177-95 (incorporated by
reference - see § 60.17) for each gross sample from each fuel
lot.
12.5.2.2.2 Lot Size. For the purpose of section 12.5.2 (fuel
pretreatment), the lot size of a product oil is the weight of
product oil from one pretreatment facility and intended as one
shipment (ship load, barge load, etc.). The lot size of raw oil is
the weight of each crude liquid fuel type used to produce a lot of
product oil.
Note:
Alternative definitions of lot sizes may be used, subject to
prior approval of the Administrator.
12.5.2.2.3 Sample Analysis. Use ASTM D 129-64, 78, or 95, ASTM D
1552-83 or 95, or ASTM D 4057-81 or 95 to determine the sulfur
content (%S) and ASTM D 240-76 or 92 (all standards cited are
incorporated by reference - see § 60.17) to determine the GCV of
each gross sample. These values may be assumed to be on a dry
basis. The owner or operator of an affected facility may elect to
determine the GCV by sampling the oil combusted on the first steam
generating unit operating day of each calendar month and then using
the lowest GCV value of the three GCV values per quarter for the
GCV of all oil combusted in that calendar quarter.
12.5.2.3 Use appropriate procedures, subject to the approval of
the Administrator, to determine the fraction of total mass input
derived from each type of fuel.
12.5.3 Control Device Removal Efficiency. Compute the percent
removal efficiency (%Rg) of the control device using the following
equation:
12.5.3.1 Use continuous emission monitoring systems or test
methods, as appropriate, to determine the outlet SO2 rates and, if
appropriate, the inlet SO2 rates. The rates may be determined as
hourly (Eh) or other sampling period averages (Ed). Then, compute
the average pollutant rates for the performance test period (Eao
and Eai) using the procedures in section 12.4.
12.5.3.2 As an alternative, as-fired fuel sampling and analysis
may be used to determine inlet SO2 rates as follows:
12.5.3.2.1 Compute the average inlet SO2 rate (Edi) for each
sampling period using the following equation:
Where: After calculating
Edi, use the procedures in section 12.4 to determine the average
inlet SO2 rate for the performance test period (Eai).
12.5.3.2.2 Collect the fuel samples from a location in the fuel
handling system that provides a sample representative of the fuel
bunkered or consumed during a steam generating unit operating day.
For the purpose of as-fired fuel sampling under section 12.5.3.2 or
section 12.6, the lot size for coal is the weight of coal bunkered
or consumed during each steam generating unit operating day. The
lot size for oil is the weight of oil supplied to the “day” tank or
consumed during each steam generating unit operating day. For
reporting and calculation purposes, the gross sample shall be
identified with the calendar day on which sampling began. For steam
generating unit operating days when a coal-fired steam generating
unit is operated without coal being added to the bunkers, the coal
analysis from the previous “as bunkered” coal sample shall be used
until coal is bunkered again. For steam generating unit operating
days when an oil-fired steam generating unit is operated without
oil being added to the oil “day” tank, the oil analysis from the
previous day shall be used until the “day” tank is filled again.
Alternative definitions of fuel lot size may be used, subject to
prior approval of the Administrator.
12.5.3.2.3 Use ASTM procedures specified in section 12.5.2.1 or
12.5.2.2 to determine %S and GCV.
12.5.4 Daily Geometric Average Percent Reduction from Hourly
Values. The geometric average percent reduction (%Rga) is computed
using the following equation:
Note:
The calculation includes only paired data sets (hourly average)
for the inlet and outlet pollutant measurements.
12.6 Sulfur Retention Credit for Compliance Fuel. If fuel
sampling and analysis procedures in section 12.5.2.1 are being used
to determine average SO2 emission rates (Eas) to the atmosphere
from a coal-fired steam generating unit when there is no SO2
control device, the following equation may be used to adjust the
emission rate for sulfur retention credits (no credits are allowed
for oil-fired systems) (Edi) for each sampling period using the
following equation:
Where:
After calculating Edi, use the procedures in section 12.4.2 to
determine the average SO2 emission rate to the atmosphere for the
performance test period (Eao).
12.7 Determination of Compliance When Minimum Data Requirement
Is Not Met.
12.7.1 Adjusted Emission Rates and Control Device Removal
Efficiency. When the minimum data requirement is not met, the
Administrator may use the following adjusted emission rates or
control device removal efficiencies to determine compliance with
the applicable standards.
12.7.1.1 Emission Rate. Compliance with the emission rate
standard may be determined by using the lower confidence limit of
the emission rate (Eao*) as follows:
12.7.1.2 Control Device Removal Efficiency. Compliance with the
overall emission reduction (%Ro) may be determined by using the
lower confidence limit of the emission rate (Eao*) and the upper
confidence limit of the inlet pollutant rate (Eai*) in calculating
the control device removal efficiency (%Rg) as follows:
12.7.2 Standard Deviation of Hourly Average Pollutant Rates.
Compute the standard deviation (Se) of the hourly average pollutant
rates using the following equation:
Equation 19-19 through 19-31 may be used to compute the standard
deviation for both the outlet (So) and, if applicable, inlet (Si)
pollutant rates.
1 Determined at standard
conditions: 20 °C (68 °F) and 760 mm Hg (29.92 in Hg)
2 As classified according to ASTM
D 388.
3 Crude, residual, or
distillate.
Table 19-3 - Values for T0.95*
n 1
t0.95
n 1
t0.95
n 1
t0.95
2
6.31
8
1.89
22-26
1.71
3
2.42
9
1.86
27-31
1.70
4
2.35
10
1.83
32-51
1.68
5
2.13
11
1.81
52-91
1.67
6
2.02
12-16
1.77
92-151
1.66
7
1.94
17-21
1.73
152 or more
1.65
1The values of this table are
corrected for n-1 degrees of freedom. Use n equal to the number (H)
of hourly average data points.
Method 20 - Determination of Nitrogen Oxides, Sulfur Dioxide, and
Diluent Emissions From Stationary Gas Turbines 1.0 Scope and
Application What is Method 20?
Method 20 contains the details you must follow when using an
instrumental analyzer to determine concentrations of nitrogen
oxides, oxygen, carbon dioxide, and sulfur dioxide in the emissions
from stationary gas turbines. This method follows the specific
instructions for equipment and performance requirements, supplies,
sample collection and analysis, calculations, and data analysis in
the methods listed in section 2.0.
1.1 Analytes. What does this method determine?
Analyte
CAS No.
Sensitivity
Nitrogen oxides
(NOX) as nitrogen dioxide:
10102-43-9
Typically <2% of
Calibration Span.
Nitric oxide
(NO)
10102-44-0
Nitrogen
dioxide NO2
Diluent oxygen
(O2) or carbon dioxide (CO2)
Typically <2% of
Calibration Span.
Sulfur dioxide
(SOX)
7446-09-5
Typically <2% of
Calibration Span.
1.2 Applicability. When is this method required? The use
of Method 20 may be required by specific New Source Performance
Standards, Clean Air Marketing rules, and State Implementation
Plans and permits where measuring SO2, NOX, CO2, and/or O2
concentrations in stationary gas turbines emissions are required.
Other regulations may also require its use.
1.3 Data Quality Objectives. How good must my collected data
be? Refer to section 1.3 of Method 7E.
2.0 Summary of Method
In this method, NOX, O2 (or CO2), and SOX are measured using the
following methods found in appendix A to this part:
(a) Method 1 - Sample and Velocity Traverses for Stationary
Sources.
(b) Method 3A - Determination of Oxygen and Carbon Dioxide
Emissions From Stationary Sources (Instrumental Analyzer
Procedure).
(c) Method 6C - Determination of Sulfur Dioxide Emissions From
Stationary Sources (Instrumental Analyzer Procedure).
(d) Method 7E - Determination of Nitrogen Oxides Emissions From
Stationary Sources (Instrumental Analyzer Procedure).
(e) Method 19 - Determination of Sulfur Dioxide Removal
Efficiency and Particulate Matter, Sulfur Dioxide, and Nitrogen
Oxide Emission Rates.
3.0 Definitions
Refer to section 3.0 of Method 7E for the applicable
definitions.
4.0 Interferences
Refer to section 4.0 of Methods 3A, 6C, and 7E as
applicable.
5.0 Safety
Refer to section 5.0 of Method 7E.
6.0 Equipment and Supplies
The measurement system design is shown in Figure 7E-1 of Method
7E. Refer to the appropriate methods listed in section 2.0 for
equipment and supplies.
7.0 Reagents and Standards
Refer to the appropriate methods listed in section 2.0 for
reagents and standards.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Sampling Site and Sampling Points. Follow the
procedures of section 8.1 of Method 7E. For the stratification test
in section 8.1.2, determine the diluent-corrected pollutant
concentration at each traverse point.
8.2 Initial Measurement System Performance Tests. You
must refer to the appropriate methods listed in section 2.0 for the
measurement system performance tests as applicable.
8.3 Interference Check. You must follow the procedures in
section 8.3 of Method 3A or 6C, or section 8.2.7 of Method 7E (as
appropriate).
8.4 Sample Collection. You must follow the procedures of
section 8.4 of the appropriate methods listed in section 2.0. A
test run must have a duration of at least 21 minutes.
8.5 Post-Run System Bias Check, Drift Assessment, and
Alternative Dynamic Spike Procedure. You must follow the
procedures of sections 8.5 and 8.6 of the appropriate methods
listed in section 2.0. A test run must have a duration of at least
21 minutes.
9.0 Quality Control
Follow quality control procedures in section 9.0 of Method
7E.
10.0 Calibration and Standardization
Follow the procedures for calibration and standardization in
section 10.0 of Method 7E.
11.0 Analytical Procedures
Because sample collection and analysis are performed together
(see section 8), additional discussion of the analytical procedure
is not necessary.
12.0 Calculations and Data Analysis
You must follow the procedures for calculations and data
analysis in section 12.0 of the appropriate method listed in
section 2.0. Follow the procedures in section 12.0 of Method 19 for
calculating fuel-specific F factors, diluent-corrected pollutant
concentrations, and emission rates.
13.0 Method Performance
The specifications for the applicable performance checks are the
same as in section 13.0 of Method 7E.
Refer to section 16.0 of the appropriate method listed in
section 2.0 for alternative procedures.
17.0 References
Refer to section 17.0 of the appropriate method listed in
section 2.0 for references.
18.0 Tables, Diagrams, Flowcharts, and Validation Data
Refer to section 18.0 of the appropriate method listed in
section 2.0 for tables, diagrams, flowcharts, and validation
data.
Method 21 - Determination of Volatile Organic Compound Leaks 1.0
Scope and Application
1.1 Analytes.
Analyte
CAS No.
Volatile Organic
Compounds (VOC)
No CAS number assigned.
1.2 Scope. This method is applicable for the determination of
VOC leaks from process equipment. These sources include, but are
not limited to, valves, flanges and other connections, pumps and
compressors, pressure relief devices, process drains, open-ended
valves, pump and compressor seal system degassing vents,
accumulator vessel vents, agitator seals, and access door
seals.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A portable instrument is used to detect VOC leaks from
individual sources. The instrument detector type is not specified,
but it must meet the specifications and performance criteria
contained in section 6.0. A leak definition concentration based on
a reference compound is specified in each applicable regulation.
This method is intended to locate and classify leaks only, and is
not to be used as a direct measure of mass emission rate from
individual sources.
3.0 Definitions
3.1 Calibration gas means the VOC compound used to adjust
the instrument meter reading to a known value. The calibration gas
is usually the reference compound at a known concentration
approximately equal to the leak definition concentration.
3.2 Calibration precision means the degree of agreement
between measurements of the same known value, expressed as the
relative percentage of the average difference between the meter
readings and the known concentration to the known
concentration.
3.3 Leak definition concentration means the local VOC
concentration at the surface of a leak source that indicates that a
VOC emission (leak) is present. The leak definition is an
instrument meter reading based on a reference compound.
3.4 No detectable emission means a local VOC
concentration at the surface of a leak source, adjusted for local
VOC ambient concentration, that is less than 2.5 percent of the
specified leak definition concentration. that indicates that a VOC
emission (leak) is not present.
3.5 Reference compound means the VOC species selected as
the instrument calibration basis for specification of the leak
definition concentration. (For example, if a leak definition
concentration is 10,000 ppm as methane, then any source emission
that results in a local concentration that yields a meter reading
of 10,000 on an instrument meter calibrated with methane would be
classified as a leak. In this example, the leak definition
concentration is 10,000 ppm and the reference compound is
methane.)
3.6 Response factor means the ratio of the known
concentration of a VOC compound to the observed meter reading when
measured using an instrument calibrated with the reference compound
specified in the applicable regulation.
3.7 Response time means the time interval from a step
change in VOC concentration at the input of the sampling system to
the time at which 90 percent of the corresponding final value is
reached as displayed on the instrument readout meter.
4.0 Interferences [Reserved] 5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Hazardous Pollutants. Several of the compounds, leaks of
which may be determined by this method, may be irritating or
corrosive to tissues (e.g., heptane) or may be toxic
(e.g., benzene, methyl alcohol). Nearly all are fire
hazards. Compounds in emissions should be determined through
familiarity with the source. Appropriate precautions can be found
in reference documents, such as reference No. 4 in section
16.0.
6.0 Equipment and Supplies
A VOC monitoring instrument meeting the following specifications
is required:
6.1 The VOC instrument detector shall respond to the compounds
being processed. Detector types that may meet this requirement
include, but are not limited to, catalytic oxidation, flame
ionization, infrared absorption, and photoionization.
6.2 The instrument shall be capable of measuring the leak
definition concentration specified in the regulation.
6.3 The scale of the instrument meter shall be readable to ±2.5
percent of the specified leak definition concentration.
6.4 The instrument shall be equipped with an electrically driven
pump to ensure that a sample is provided to the detector at a
constant flow rate. The nominal sample flow rate, as measured at
the sample probe tip, shall be 0.10 to 3.0 l/min (0.004 to 0.1 ft
3/min) when the probe is fitted with a glass wool plug or filter
that may be used to prevent plugging of the instrument.
6.5 The instrument shall be equipped with a probe or probe
extension or sampling not to exceed 6.4 mm ( 1/4 in) in outside
diameter, with a single end opening for admission of sample.
6.6 The instrument shall be intrinsically safe for operation in
explosive atmospheres as defined by the National Electrical Code by
the National Fire Prevention Association or other applicable
regulatory code for operation in any explosive atmospheres that may
be encountered in its use. The instrument shall, at a minimum, be
intrinsically safe for Class 1, Division 1 conditions, and/or Class
2, Division 1 conditions, as appropriate, as defined by the example
code. The instrument shall not be operated with any safety device,
such as an exhaust flame arrestor, removed.
7.0 Reagents and Standards
7.1 Two gas mixtures are required for instrument calibration and
performance evaluation:
7.1.1 Zero Gas. Air, less than 10 parts per million by volume
(ppmv) VOC.
7.1.2 Calibration Gas. For each organic species that is to be
measured during individual source surveys, obtain or prepare a
known standard in air at a concentration approximately equal to the
applicable leak definition specified in the regulation.
7.2 Cylinder Gases. If cylinder calibration gas mixtures are
used, they must be analyzed and certified by the manufacturer to be
within 2 percent accuracy, and a shelf life must be specified.
Cylinder standards must be either reanalyzed or replaced at the end
of the specified shelf life.
7.3 Prepared Gases. Calibration gases may be prepared by the
user according to any accepted gaseous preparation procedure that
will yield a mixture accurate to within 2 percent. Prepared
standards must be replaced each day of use unless it is
demonstrated that degradation does not occur during storage.
7.4 Mixtures with non-Reference Compound Gases. Calibrations may
be performed using a compound other than the reference compound. In
this case, a conversion factor must be determined for the
alternative compound such that the resulting meter readings during
source surveys can be converted to reference compound results.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Instrument Performance Evaluation. Assemble and start up the
instrument according to the manufacturer's instructions for
recommended warmup period and preliminary adjustments.
8.1.1 Response Factor. A response factor must be determined for
each compound that is to be measured, either by testing or from
reference sources. The response factor tests are required before
placing the analyzer into service, but do not have to be repeated
at subsequent intervals.
8.1.1.1 Calibrate the instrument with the reference compound as
specified in the applicable regulation. Introduce the calibration
gas mixture to the analyzer and record the observed meter reading.
Introduce zero gas until a stable reading is obtained. Make a total
of three measurements by alternating between the calibration gas
and zero gas. Calculate the response factor for each repetition and
the average response factor.
8.1.1.2 The instrument response factors for each of the
individual VOC to be measured shall be less than 10 unless
otherwise specified in the applicable regulation. When no
instrument is available that meets this specification when
calibrated with the reference VOC specified in the applicable
regulation, the available instrument may be calibrated with one of
the VOC to be measured, or any other VOC, so long as the instrument
then has a response factor of less than 10 for each of the
individual VOC to be measured.
8.1.1.3 Alternatively, if response factors have been published
for the compounds of interest for the instrument or detector type,
the response factor determination is not required, and existing
results may be referenced. Examples of published response factors
for flame ionization and catalytic oxidation detectors are included
in References 1-3 of section 17.0.
8.1.2 Calibration Precision. The calibration precision test must
be completed prior to placing the analyzer into service and at
subsequent 3-month intervals or at the next use, whichever is
later.
8.1.2.1 Make a total of three measurements by alternately using
zero gas and the specified calibration gas. Record the meter
readings. Calculate the average algebraic difference between the
meter readings and the known value. Divide this average difference
by the known calibration value and multiply by 100 to express the
resulting calibration precision as a percentage.
8.1.2.2 The calibration precision shall be equal to or less than
10 percent of the calibration gas value.
8.1.3 Response Time. The response time test is required before
placing the instrument into service. If a modification to the
sample pumping system or flow configuration is made that would
change the response time, a new test is required before further
use.
8.1.3.1 Introduce zero gas into the instrument sample probe.
When the meter reading has stabilized, switch quickly to the
specified calibration gas. After switching, measure the time
required to attain 90 percent of the final stable reading. Perform
this test sequence three times and record the results. Calculate
the average response time.
8.1.3.2 The instrument response time shall be equal to or less
than 30 seconds. The instrument pump, dilution probe (if any),
sample probe, and probe filter that will be used during testing
shall all be in place during the response time determination.
8.2 Instrument Calibration. Calibrate the VOC monitoring
instrument according to section 10.0.
8.3 Individual Source Surveys.
8.3.1 Type I - Leak Definition Based on Concentration. Place the
probe inlet at the surface of the component interface where leakage
could occur. Move the probe along the interface periphery while
observing the instrument readout. If an increased meter reading is
observed, slowly sample the interface where leakage is indicated
until the maximum meter reading is obtained. Leave the probe inlet
at this maximum reading location for approximately two times the
instrument response time. If the maximum observed meter reading is
greater than the leak definition in the applicable regulation,
record and report the results as specified in the regulation
reporting requirements. Examples of the application of this general
technique to specific equipment types are:
8.3.1.1 Valves. The most common source of leaks from valves is
the seal between the stem and housing. Place the probe at the
interface where the stem exits the packing gland and sample the
stem circumference. Also, place the probe at the interface of the
packing gland take-up flange seat and sample the periphery. In
addition, survey valve housings of multipart assembly at the
surface of all interfaces where a leak could occur.
8.3.1.2 Flanges and Other Connections. For welded flanges, place
the probe at the outer edge of the flange-gasket interface and
sample the circumference of the flange. Sample other types of
nonpermanent joints (such as threaded connections) with a similar
traverse.
8.3.1.3 Pumps and Compressors. Conduct a circumferential
traverse at the outer surface of the pump or compressor shaft and
seal interface. If the source is a rotating shaft, position the
probe inlet within 1 cm of the shaft-seal interface for the survey.
If the housing configuration prevents a complete traverse of the
shaft periphery, sample all accessible portions. Sample all other
joints on the pump or compressor housing where leakage could
occur.
8.3.1.4 Pressure Relief Devices. The configuration of most
pressure relief devices prevents sampling at the sealing seat
interface. For those devices equipped with an enclosed extension,
or horn, place the probe inlet at approximately the center of the
exhaust area to the atmosphere.
8.3.1.5 Process Drains. For open drains, place the probe inlet
at approximately the center of the area open to the atmosphere. For
covered drains, place the probe at the surface of the cover
interface and conduct a peripheral traverse.
8.3.1.6 Open-ended Lines or Valves. Place the probe inlet at
approximately the center of the opening to the atmosphere.
8.3.1.7 Seal System Degassing Vents and Accumulator Vents. Place
the probe inlet at approximately the center of the opening to the
atmosphere.
8.3.1.8 Access door seals. Place the probe inlet at the surface
of the door seal interface and conduct a peripheral traverse.
8.3.2 Type II - “No Detectable Emission”. Determine the local
ambient VOC concentration around the source by moving the probe
randomly upwind and downwind at a distance of one to two meters
from the source. If an interference exists with this determination
due to a nearby emission or leak, the local ambient concentration
may be determined at distances closer to the source, but in no case
shall the distance be less than 25 centimeters. Then move the probe
inlet to the surface of the source and determine the concentration
as outlined in section 8.3.1. The difference between these
concentrations determines whether there are no detectable
emissions. Record and report the results as specified by the
regulation. For those cases where the regulation requires a
specific device installation, or that specified vents be ducted or
piped to a control device, the existence of these conditions shall
be visually confirmed. When the regulation also requires that no
detectable emissions exist, visual observations and sampling
surveys are required. Examples of this technique are:
8.3.2.1 Pump or Compressor Seals. If applicable, determine the
type of shaft seal. Perform a survey of the local area ambient VOC
concentration and determine if detectable emissions exist as
described in section 8.3.2.
8.3.2.2 Seal System Degassing Vents, Accumulator Vessel Vents,
Pressure Relief Devices. If applicable, observe whether or not the
applicable ducting or piping exists. Also, determine if any sources
exist in the ducting or piping where emissions could occur upstream
of the control device. If the required ducting or piping exists and
there are no sources where the emissions could be vented to the
atmosphere upstream of the control device, then it is presumed that
no detectable emissions are present. If there are sources in the
ducting or piping where emissions could be vented or sources where
leaks could occur, the sampling surveys described in section 8.3.2
shall be used to determine if detectable emissions exist.
8.3.3 Alternative Screening Procedure.
8.3.3.1 A screening procedure based on the formation of bubbles
in a soap solution that is sprayed on a potential leak source may
be used for those sources that do not have continuously moving
parts, that do not have surface temperatures greater than the
boiling point or less than the freezing point of the soap solution,
that do not have open areas to the atmosphere that the soap
solution cannot bridge, or that do not exhibit evidence of liquid
leakage. Sources that have these conditions present must be
surveyed using the instrument technique of section 8.3.1 or
8.3.2.
8.3.3.2 Spray a soap solution over all potential leak sources.
The soap solution may be a commercially available leak detection
solution or may be prepared using concentrated detergent and water.
A pressure sprayer or squeeze bottle may be used to dispense the
solution. Observe the potential leak sites to determine if any
bubbles are formed. If no bubbles are observed, the source is
presumed to have no detectable emissions or leaks as applicable. If
any bubbles are observed, the instrument techniques of section
8.3.1 or 8.3.2 shall be used to determine if a leak exists, or if
the source has detectable emissions, as applicable.
9.0 Quality Control
Section
Quality control measure
Effect
8.1.2
Instrument calibration
precision check
Ensure precision and accuracy,
respectively, of instrument response to standard.
10.0
Instrument calibration
10.0 Calibration and Standardization
10.1 Calibrate the VOC monitoring instrument as follows. After
the appropriate warmup period and zero internal calibration
procedure, introduce the calibration gas into the instrument sample
probe. Adjust the instrument meter readout to correspond to the
calibration gas value.
Note:
If the meter readout cannot be adjusted to the proper value, a
malfunction of the analyzer is indicated and corrective actions are
necessary before use.
1. Dubose, D.A., and G.E. Harris. Response Factors of VOC
Analyzers at a Meter Reading of 10,000 ppmv for Selected Organic
Compounds. U.S. Environmental Protection Agency, Research Triangle
Park, NC. Publication No. EPA 600/2-81051. September 1981.
2. Brown, G.E., et al. Response Factors of VOC Analyzers
Calibrated with Methane for Selected Organic Compounds. U.S.
Environmental Protection Agency, Research Triangle Park, NC.
Publication No. EPA 600/2-81-022. May 1981.
3. DuBose, D.A. et al. Response of Portable VOC Analyzers
to Chemical Mixtures. U.S. Environmental Protection Agency,
Research Triangle Park, NC. Publication No. EPA 600/2-81-110.
September 1981.
4. Handbook of Hazardous Materials: Fire, Safety, Health.
Alliance of American Insurers. Schaumberg, IL. 1983.
17.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
Method 22 - Visual Determination of Fugitive Emissions From
Material Sources and Smoke Emissions From Flares Note:
This method is not inclusive with respect to observer
certification. Some material is incorporated by reference from
Method 9.
1.0 Scope and Application
This method is applicable for the determination of the frequency
of fugitive emissions from stationary sources, only as specified in
an applicable subpart of the regulations. This method also is
applicable for the determination of the frequency of visible smoke
emissions from flares.
2.0 Summary of Method
2.1 Fugitive emissions produced during material processing,
handling, and transfer operations or smoke emissions from flares
are visually determined by an observer without the aid of
instruments.
2.2 This method is used also to determine visible smoke
emissions from flares used for combustion of waste process
materials.
2.3 This method determines the amount of time that visible
emissions occur during the observation period (i.e., the
accumulated emission time). This method does not require that the
opacity of emissions be determined. Since this procedure requires
only the determination of whether visible emissions occur and does
not require the determination of opacity levels, observer
certification according to the procedures of Method 9 is not
required. However, it is necessary that the observer is
knowledgeable with respect to the general procedures for
determining the presence of visible emissions. At a minimum, the
observer must be trained and knowledgeable regarding the effects of
background contrast, ambient lighting, observer position relative
to lighting, wind, and the presence of uncombined water (condensing
water vapor) on the visibility of emissions. This training is to be
obtained from written materials found in References 1 and 2 or from
the lecture portion of the Method 9 certification course.
3.0 Definitions
3.1 Emission frequency means the percentage of time that
emissions are visible during the observation period.
3.2 Emission time means the accumulated amount of time
that emissions are visible during the observation period.
3.3 Fugitive emissions means emissions generated by an
affected facility which is not collected by a capture system and is
released to the atmosphere. This includes emissions that (1) escape
capture by process equipment exhaust hoods; (2) are emitted during
material transfer; (3) are emitted from buildings housing material
processing or handling equipment; or (4) are emitted directly from
process equipment.
3.4 Observation period means the accumulated time period
during which observations are conducted, not to be less than the
period specified in the applicable regulation.
3.5 Smoke emissions means a pollutant generated by
combustion in a flare and occurring immediately downstream of the
flame. Smoke occurring within the flame, but not downstream of the
flame, is not considered a smoke emission.
4.0 Interferences
4.1 Occasionally, fugitive emissions from sources other than the
affected facility (e.g., road dust) may prevent a clear view
of the affected facility. This may particularly be a problem during
periods of high wind. If the view of the potential emission points
is obscured to such a degree that the observer questions the
validity of continuing observations, then the observations shall be
terminated, and the observer shall clearly note this fact on the
data form.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment
6.1 Stopwatches (two). Accumulative type with unit divisions of
at least 0.5 seconds.
6.2 Light Meter. Light meter capable of measuring illuminance in
the 50 to 200 lux range, required for indoor observations only.
7.0 Reagents and Supplies [Reserved] 8.0 Sample Collection,
Preservation, Storage, and Transfer [Reserved] 9.0 Quality Control
[Reserved] 10.0 Calibration and Standardization [Reserved] 11.0
Analytical Procedure
11.1 Selection of Observation Location. Survey the affected
facility, or the building or structure housing the process to be
observed, and determine the locations of potential emissions. If
the affected facility is located inside a building, determine an
observation location that is consistent with the requirements of
the applicable regulation (i.e., outside observation of
emissions escaping the building/structure or inside observation of
emissions directly emitted from the affected facility process
unit). Then select a position that enables a clear view of the
potential emission point(s) of the affected facility or of the
building or structure housing the affected facility, as appropriate
for the applicable subpart. A position at least 4.6 m (15 feet),
but not more than 400 m (0.25 miles), from the emission source is
recommended. For outdoor locations, select a position where the
sunlight is not shining directly in the observer's eyes.
11.2 Field Records.
11.2.1 Outdoor Location. Record the following information on the
field data sheet (Figure 22-1): Company name, industry, process
unit, observer's name, observer's affiliation, and date. Record
also the estimated wind speed, wind direction, and sky condition.
Sketch the process unit being observed, and note the observer
location relative to the source and the sun. Indicate the potential
and actual emission points on the sketch. Alternatively, digital
photography as described in section 11.2.3 may be used for a subset
of the recordkeeping requirements of this section.
11.2.2 Indoor Location. Record the following information on the
field data sheet (Figure 22-2): Company name, industry, process
unit, observer's name, observer's affiliation, and date. Record as
appropriate the type, location, and intensity of lighting on the
data sheet. Sketch the process unit being observed, and note the
observer location relative to the source. Indicate the potential
and actual fugitive emission points on the sketch. Alternatively,
digital photography as described in section 11.2.3 may be used for
a subset of the recordkeeping requirements of this section.
11.2.3 Digital Photographic Records. Digital photographs,
annotated or unaltered, may be used to record and report sky
conditions, observer's location relative to the source, observer's
location relative to the sun, process unit being observed,
potential emission points and actual emission points for the
requirements in sections 11.2.1 and 11.2.2. The image must have the
proper lighting, field of view and depth of field to properly
distinguish the sky condition (if applicable), process unit,
potential emission point and actual emission point. At least one
digital photograph must be from the point of the view of the
observer. The photograph(s) representing the environmental
conditions including the sky conditions and the position of the sun
relative to the observer and the emission point must be taken
within a reasonable time of the observation (i.e., 15
minutes). When observations are taken from exactly the same
observation point on a routine basis (i.e., daily) and as
long as there are no modifications to the units depicted, only a
single photograph each is necessary to document the observer's
location relative to the emissions source, the process unit being
observed, and the location of potential and actual emission points.
Any photographs altered or annotated must be retained in an
unaltered format for recordkeeping purposes.
11.3 Indoor Lighting Requirements. For indoor locations, use a
light meter to measure the level of illumination at a location as
close to the emission source(s) as is feasible. An illumination of
greater than 100 lux (10 foot candles) is considered necessary for
proper application of this method.
11.4 Observations.
11.4.1 Procedure. Record the clock time when observations begin.
Use one stopwatch to monitor the duration of the observation
period. Start this stopwatch when the observation period begins. If
the observation period is divided into two or more segments by
process shutdowns or observer rest breaks (see section 11.4.3),
stop the stopwatch when a break begins and restart the stopwatch
without resetting it when the break ends. Stop the stopwatch at the
end of the observation period. The accumulated time indicated by
this stopwatch is the duration of observation period. When the
observation period is completed, record the clock time. During the
observation period, continuously watch the emission source. Upon
observing an emission (condensed water vapor is not considered an
emission), start the second accumulative stopwatch; stop the watch
when the emission stops. Continue this procedure for the entire
observation period. The accumulated elapsed time on this stopwatch
is the total time emissions were visible during the observation
period (i.e., the emission time.)
11.4.2 Observation Period. Choose an observation period of
sufficient length to meet the requirements for determining
compliance with the emission standard in the applicable subpart of
the regulations. When the length of the observation period is
specifically stated in the applicable subpart, it may not be
necessary to observe the source for this entire period if the
emission time required to indicate noncompliance (based on the
specified observation period) is observed in a shorter time period.
In other words, if the regulation prohibits emissions for more than
6 minutes in any hour, then observations may (optional) be stopped
after an emission time of 6 minutes is exceeded. Similarly, when
the regulation is expressed as an emission frequency and the
regulation prohibits emissions for greater than 10 percent of the
time in any hour, then observations may (optional) be terminated
after 6 minutes of emission are observed since 6 minutes is 10
percent of an hour. In any case, the observation period shall not
be less than 6 minutes in duration. In some cases, the process
operation may be intermittent or cyclic. In such cases, it may be
convenient for the observation period to coincide with the length
of the process cycle.
11.4.3 Observer Rest Breaks. Do not observe emissions
continuously for a period of more than 15 to 20 minutes without
taking a rest break. For sources requiring observation periods of
greater than 20 minutes, the observer shall take a break of not
less than 5 minutes and not more than 10 minutes after every 15 to
20 minutes of observation. If continuous observations are desired
for extended time periods, two observers can alternate between
making observations and taking breaks.
11.5 Recording Observations. Record the accumulated time of the
observation period on the data sheet as the observation period
duration. Record the accumulated time emissions were observed on
the data sheet as the emission time. Record the clock time the
observation period began and ended, as well as the clock time any
observer breaks began and ended.
12.0 Data Analysis and Calculations
If the applicable subpart requires that the emission rate be
expressed as an emission frequency (in percent), determine this
value as follows: Divide the accumulated emission time (in seconds)
by the duration of the observation period (in seconds) or by any
minimum observation period required in the applicable subpart, if
the actual observation period is less than the required period, and
multiply this quotient by 100.
1. Missan, R., and A. Stein. Guidelines for Evaluation of
Visible Emissions Certification, Field Procedures, Legal Aspects,
and Background Material. EPA Publication No. EPA-340/1-75-007.
April 1975.
2. Wohlschlegel, P., and D.E. Wagoner. Guideline for Development
of a Quality Assurance Program: Volume IX - Visual Determination of
Opacity Emissions from Stationary Sources. EPA Publication No.
EPA-650/4-74-005i. November 1975.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 23 -
Determination of Polychlorinated Dibenzo-p-Dioxins and
Polychlorinated Dibenzofurans From Stationary Sources 1.
Applicability and Principle
1.1 Applicability. This method is applicable to the
determination of polychlorinated dibenzo-p-dioxins (PCDD's) and
polychlorinated dibenzofurans (PCDF's) from stationary sources.
1.2 Principle. A sample is withdrawn from the gas stream
isokinetically and collected in the sample probe, on a glass fiber
filter, and on a packed column of adsorbent material. The sample
cannot be separated into a particle vapor fraction. The PCDD's and
PCDF's are extracted from the sample, separated by high resolution
gas chromatography, and measured by high resolution mass
spectrometry.
2. Apparatus
2.1 Sampling. A schematic of the sampling train used in this
method is shown in Figure 23-1. Sealing greases may not be used in
assembling the train. The train is identical to that described in
section 2.1 of Method 5 of this appendix with the following
additions:
2.1.1 Nozzle. The nozzle shall be made of nickel, nickel-plated
stainless steel, quartz, or borosilicate glass.
2.1.2 Sample Transfer Lines. The sample transfer lines, if
needed, shall be heat traced, heavy walled TFE ( 1/2 in. OD with
1/8 in. wall) with connecting fittings that are capable of forming
leak-free, vacuum-tight connections without using sealing greases.
The line shall be as short as possible and must be maintained at
120 °C.
2.1.1 Filter Support. Teflon or Teflon-coated wire.
2.1.2 Condenser. Glass, coil type with compatible fittings. A
schematic diagram is shown in Figure 23-2.
2.1.3 Water Bath. Thermostatically controlled to maintain the
gas temperature exiting the condenser at <20 °C (68 °F).
2.1.4 Adsorbent Module. Glass container to hold the solid
adsorbent. A shematic diagram is shown in Figure 23-2. Other
physical configurations of the resin trap/condenser assembly are
acceptable. The connecting fittings shall form leak-free, vacuum
tight seals. No sealant greases shall be used in the sampling
train. A coarse glass frit is included to retain the adsorbent.
2.2 Sample Recovery.
2.2.1 Fitting Caps. Ground glass, Teflon tape, or aluminum foil
(Section 2.2.6) to cap off the sample exposed sections of the
train.
2.2.2 Wash Bottles. Teflon, 500-ml.
2.2.3 Probe-Liner Probe-Nozzle, and Filter-Holder Brushes. Inert
bristle brushes with precleaned stainless steel or Teflon handles.
The probe brush shall have extensions of stainless steel or Teflon,
at least as long as the probe. The brushes shall be properly sized
and shaped to brush out the nozzle, probe liner, and transfer line,
if used.
2.2.4 Filter Storage Container. Sealed filter holder, wide-mouth
amber glass jar with Teflon-lined cap, or glass petri dish.
2.2.5 Balance. Triple beam.
2.2.6 Aluminum Foil. Heavy duty, hexane-rinsed.
2.2.7 Storage Container. Air-tight container to store silica
gel.
2.2.8 Graduated Cylinder. Glass, 250-ml with 2-ml
graduation.
2.2.9 Glass Sample Storage Container. Amber glass bottle for
sample glassware washes, 500- or 1000-ml, with leak free
Teflon-lined caps.
2.3 Analysis.
2.3.1 Sample Container. 125- and 250-ml flint glass bottles with
Teflon-lined caps.
2.3.2 Test Tube. Glass.
2.3.3 Soxhlet Extraction Apparatus. Capable of holding 43 × 123
mm extraction thimbles.
2.3.4 Extraction Thimble. Glass, precleaned cellulosic, or glass
fiber.
2.3.5 Pasteur Pipettes. For preparing liquid chromatographic
columns.
2.3.6 Reacti-vials. Amber glass, 2-ml, silanized prior to
use.
2.3.7 Rotary Evaporator. Buchi/Brinkman RF-121 or
equivalent.
2.3.8 Nitrogen Evaporative Concentrator. N-Evap Analytical
Evaporator Model III or equivalent.
2.3.9 Separatory Funnels. Glass, 2-liter.
2.3.10 Gas Chromatograph. Consisting of the following
components:
2.3.10.1 Oven. Capable of maintaining the separation column at
the proper operating temperature ±°C and performing programmed
increases in temperature at rates of at least 40 °C/min.
2.3.10.2 Temperature Gauge. To monitor column oven, detector,
and exhaust temperatures ±1 °C.
2.3.10.3 Flow System. Gas metering system to measure sample,
fuel, combustion gas, and carrier gas flows.
2.3.10.4 Capillary Columns. A fused silica column, 60 × 0.25 mm
inside diameter (ID), coated with DB-5 and a fused silica column,
30 m × 0.25 mm ID coated with DB-225. Other column systems may be
used provided that the user is able to demonstrate using
calibration and performance checks that the column system is able
to meet the specifications of section 6.1.2.2.
2.3.11 Mass Spectrometer. Capable of routine operation at a
resolution of 1:10000 with a stability of ±5 ppm.
2.3.12 Data System. Compatible with the mass spectrometer and
capable of monitoring at least five groups of 25 ions.
2.3.13 Analytical Balance. To measure within 0.1 mg.
3. Reagents
3.1 Sampling.
3.1.1 Filters. Glass fiber filters, without organic binder,
exhibiting at least 99.95 percent efficiency (<0.05 percent
penetration) on 0.3-micron dioctyl phthalate smoke particles. The
filter efficiency test shall be conducted in accordance with ASTM
Standard Method D 2986-71 (Reapproved 1978) (incorporated by
reference - see § 60.17).
3.1.1.1 Precleaning. All filters shall be cleaned before their
initial use. Place a glass extraction thimble and 1 g of silica gel
and a plug of glass wool into a Soxhlet apparatus, charge the
apparatus with toluene, and reflux for a minimum of 3 hours. Remove
the toluene and discard it, but retain the silica gel. Place no
more than 50 filters in the thimble onto the silica gel bed and top
with the cleaned glass wool. Charge the Soxhlet with toluene and
reflux for 16 hours. After extraction, allow the Soxhlet to cool,
remove the filters, and dry them under a clean N2 stream. Store the
filters in a glass petri dish sealed with Teflon tape.
3.1.2.1 Cleaning Procedure. This procedure may be carried out in
a giant Soxhlet extractor. An all-glass filter thimble containing
an extra-course frit is used for extraction of XAD-2. The frit is
recessed 10-15 mm above a crenelated ring at the bottom of the
thimble to facilitate drainage. The resin must be carefully
retained in the extractor cup with a glass wool plug and a
stainless steel ring because it floats on methylene chloride. This
process involves sequential extraction in the following order.
Solvent
Procedure
Water
Initial rinse: Place resin in
a beaker, rinse once with water, and discard. Fill with water a
second time, let stand overnight, and discard.
Water
Extract with water for 8
hours.
Methanol
Extract for 22 hours.
Methylene
Chloride
Extract for 22 hours.
Toluene
Extract for 22 hours.
3.1.2.2 Drying.
3.1.2.2.1 Drying Column. Pyrex pipe, 10.2 cm ID by 0.6 m long,
with suitable retainers.
3.1.2.2.2 Procedure. The adsorbent must be dried with clean
inert gas. Liquid nitrogen from a standard commercial liquid
nitrogen cylinder has proven to be a reliable source of large
volumes of gas free from organic contaminants. Connect the liquid
nitrogen cylinder to the column by a length of cleaned copper
tubing, 0.95 cm ID, coiled to pass through a heat source. A
convenient heat source is a water-bath heated from a steam line.
The final nitrogen temperature should only be warm to the touch and
not over 40 °C. Continue flowing nitrogen through the adsorbent
until all the residual solvent is removed. The flow rate should be
sufficient to gently agitate the particles but not so excessive as
the cause the particles to fracture.
3.1.2.3 Quality Control Check. The adsorbent must be checked for
residual toluene.
3.1.2.3.1 Extraction. Weigh 1.0 g sample of dried resin into a
small vial, add 3 ml of toluene, cap the vial, and shake it
well.
3.1.2.3.2 Analysis. Inject a 2 µl sample of the extract into a
gas chromatograph operated under the following conditions:
Column: 6 ft × 1/8 in stainless steel containing 10 percent OV-101
on 100/120 Supelcoport. Carrier Gas: Helium at a rate of 30 ml/min.
Detector: Flame ionization detector operated at a sensitivity of 4
× 10−11 A/mV. Injection Port Temperature: 250 °C. Detector
Temperature: 305 °C. Oven Temperature: 30 °C for 4 min; programmed
to rise at 40 °C/min until it reaches 250 °C; return to 30 °C after
17 minutes.
Compare the results of the analysis to the results from the
reference solution. Prepare the reference solution by injection 2.5
µl of methylene chloride into 100 ml of toluene. This corresponds
to 100 µg of methylene chloride per g of adsorbent. The maximum
acceptable concentration is 1000 µg/g of adsorbent. If the
adsorbent exceeds this level, drying must be continued until the
excess methylene chloride is removed.
3.1.2.4 Storage. The adsorbent must be used within 4 weeks of
cleaning. After cleaning, it may be stored in a wide mouth amber
glass container with a Teflon-lined cap or placed in one of the
glass adsorbent modules tightly sealed with glass stoppers. If
precleaned adsorbent is purchased in sealed containers, it must be
used within 4 weeks after the seal is broken.
3.1.3 Glass Wool. Cleaned by sequential immersion in three
aliquots of methylene chloride, dried in a 110 °C oven, and stored
in a methylene chloride-washed glass jar with a Teflon-lined screw
cap.
3.1.4 Water. Deionized distilled and stored in a methylene
chloride-rinsed glass container with a Teflon-lined screw cap.
3.1.5 Silica Gel. Indicating type, 6 to 16 mesh. If previously
used, dry at 175 °C (350 °F) for two hours. New silica gel may be
used as received. Alternately other types of desiccants (equivalent
or better) may be used, subject to the approval of the
Administrator.
3.1.6 Chromic Acid Cleaning Solution. Dissolve 20 g of sodium
dichromate in 15 ml of water, and then carefully add 400 ml of
concentrated sulfuric acid.
3.2 Sample Recovery.
3.2.2 Acetone. Pesticide quality.
3.2.2 Methylene Chloride. Pesticide qualtity.
3.2.3 Toluene. Pesticide quality.
3.3 Analysis.
3.3.1 Potassium Hydroxide. ACS grade, 2-percent (weight/volume)
in water.
3.3.2 Sodium Sulfate. Granulated, reagent grade. Purify prior to
use by rinsing with methylene chloride and oven drying. Store the
cleaned material in a glass container with a Teflon-lined screw
cap.
3.3.3 Sulfuric Acid. Reagent grade.
3.3.4 Sodium Hydroxide. 1.0 N. Weigh 40 g of sodium hydroxide
into a 1-liter volumetric flask. Dilute to 1 liter with water.
3.3.5 Hexane. Pesticide grade.
3.3.6 Methylene Chloride. Pesticide grade.
3.3.7 Benzene. Pesticide Grade.
3.3.8 Ethyl Acetate.
3.3.9 Methanol. Pesticide Grade.
3.3.10 Toluene. Pesticide Grade.
3.3.11 Nonane. Pesticide Grade.
3.3.12 Cyclohexane. Pesticide Grade.
3.3.13 Basic Alumina. Activity grade 1, 100-200 mesh. Prior to
use, activate the alumina by heating for 16 hours at 130 °C before
use. Store in a desiccator. Pre-activated alumina may be purchased
from a supplier and may be used as received.
3.3.14 Silica Gel. Bio-Sil A, 100-200 mesh. Prior to use,
activate the silica gel by heating for at least 30 minutes at 180
°C. After cooling, rinse the silica gel sequentially with methanol
and methylene chloride. Heat the rinsed silica gel at 50 °C for 10
minutes, then increase the temperature gradually to 180 °C over 25
minutes and maintain it at this temperature for 90 minutes. Cool at
room temperature and store in a glass container with a Teflon-lined
screw cap.
3.3.15 Silica Gel Impregnated with Sulfuric Acid. Combine 100 g
of silica gel with 44 g of concentrated sulfuric acid in a screw
capped glass bottle and agitate thoroughly. Disperse the solids
with a stirring rod until a uniform mixture is obtained. Store the
mixture in a glass container with a Teflon-lined screw cap.
3.3.16 Silica Gel Impregnated with Sodium Hydroxide. Combine 39
g of 1 N sodium hydroxide with 100 g of silica gel in a screw
capped glass bottle and agitate thoroughly. Disperse solids with a
stirring rod until a uniform mixture is obtained. Store the mixture
in glass container with a Teflon-lined screw cap.
3.3.17 Carbon/Celite. Combine 10.7 g of AX-21 carbon with 124 g
of Celite 545 in a 250-ml glass bottle with a Teflon-lined screw
cap. Agitate the mixture thoroughly until a uniform mixture is
obtained. Store in the glass container.
3.3.18 Nitrogen. Ultra high purity.
3.3.19 Hydrogen. Ultra high purity.
3.3.20 Internal Standard Solution. Prepare a stock standard
solution containing the isotopically labelled PCDD's and PCDF's at
the concentrations shown in Table 1 under the heading “Internal
Standards” in 10 ml of nonane.
3.3.21 Surrogate Standard Solution. Prepare a stock standard
solution containing the isotopically labelled PCDD's and PCDF's at
the concentrations shown in Table 1 under the heading “Surrogate
Standards” in 10 ml of nonane.
3.3.22 Recovery Standard Solution. Prepare a stock standard
solution containing the isotopically labelled PCDD's and PCDF's at
the concentrations shown in Table 1 under the heading “Recovery
Standards” in 10 ml of nonane.
4. Procedure
4.1 Sampling. The complexity of this method is such that, in
order to obtain reliable results, testers should be trained and
experienced with the test procedures.
4.1.1 Pretest Preparation.
4.1.1.1 Cleaning Glassware. All glass components of the train
upstream of and including the adsorbent module, shall be cleaned as
described in section 3A of the “Manual of Analytical Methods for
the Analysis of Pesticides in Human and Environmental Samples.”
Special care shall be devoted to the removal of residual silicone
grease sealants on ground glass connections of used glassware. Any
residue shall be removed by soaking the glassware for several hours
in a chromic acid cleaning solution prior to cleaning as described
above.
4.1.1.2 Adsorbent Trap. The traps must be loaded in a clean area
to avoid contamination. They may not be loaded in the field. Fill a
trap with 20 to 40 g of XAD-2. Follow the XAD-2 with glass wool and
tightly cap both ends of the trap. Add 100 µl of the surrogate
standard solution (section 3.3.21) to each trap.
4.1.1.3 Sample Train. It is suggested that all components be
maintained according to the procedure described in APTD-0576.
Alternative mercury-free thermometers may be used if the
thermometers are, at a minimum, equivalent in terms of performance
or suitably effective for the specific temperature measurement
application.
4.1.1.4 Silica Gel. Weigh several 200 to 300 g portions of
silica gel in an air tight container to the nearest 0.5 g. Record
the total weight of the silica gel plus container, on each
container. As an alternative, the silica gel may be weighed
directly in its impinger or sampling holder just prior to
sampling.
4.1.1.5 Filter. Check each filter against light for
irregularities and flaws or pinhole leaks. Pack the filters flat in
a clean glass container.
4.1.2 Preliminary Determinations. Same as section 4.1.2 of
Method 5.
4.1.3 Preparation of Collection Train.
4.1.3.1 During preparation and assembly of the sampling train,
keep all train openings where contamination can enter, sealed until
just prior to assembly or until sampling is about to begin.
Note:
Do not use sealant grease in assembling the train.
4.1.3.2 Place approximately 100 ml of water in the second and
third impingers, leave the first and fourth impingers empty, and
transfer approximately 200 to 300 g of preweighed silica gel from
its container to the fifth impinger.
4.1.3.3 Place the silica gel container in a clean place for
later use in the sample recovery. Alternatively, the weight of the
silica gel plus impinger may be determined to the nearest 0.5 g and
recorded.
4.1.3.4 Assemble the train as shown in Figure 23-1.
4.1.3.5 Turn on the adsorbent module and condenser coil
recirculating pump and begin monitoring the adsorbent module gas
entry temperature. Ensure proper sorbent temperature gas entry
temperature before proceeding and before sampling is initiated. It
is extremely important that the XAD-2 adsorbent resin temperature
never exceed 50 °C because thermal decomposition will occur. During
testing, the XAD-2 temperature must not exceed 20 °C for efficient
capture of the PCDD's and PCDF's.
4.1.4 Leak-Check Procedure. Same as Method 5, section 4.1.4.
4.1.5 Sample Train Operation. Same as Method 5, section
4.1.5.
4.2 Sample Recovery. Proper cleanup procedure begins as soon as
the probe is removed from the stack at the end of the sampling
period. Seal the nozzle end of the sampling probe with Teflon tape
or aluminum foil.
When the probe can be safely handled, wipe off all external
particulate matter near the tip of the probe. Remove the probe from
the train and close off both ends with aluminum foil. Seal off the
inlet to the train with Teflon tape, a ground glass cap, or
aluminum foil.
Transfer the probe and impinger assembly to the cleanup area.
This area shall be clean and enclosed so that the chances of losing
or contaminating the sample are minimized. Smoking, which could
contaminate the sample, shall not be allowed in the cleanup
area.
Inspect the train prior to and during disassembly and note any
abnormal conditions, e.g., broken filters, colored impinger liquid,
etc. Treat the samples as follows:
4.2.1 Container No. 1. Either seal the filter holder or
carefully remove the filter from the filter holder and place it in
its identified container. Use a pair of cleaned tweezers to handle
the filter. If it is necessary to fold the filter, do so such that
the particulate cake is inside the fold. Carefully transfer to the
container any particulate matter and filter fibers which adhere to
the filter holder gasket, by using a dry inert bristle brush and a
sharp-edged blade. Seal the container.
4.2.2 Adsorbent Module. Remove the module from the train,
tightly cap both ends, label it, cover with aluminum foil, and
store it on ice for transport to the laboratory.
4.2.3 Container No. 2. Quantitatively recover material deposited
in the nozzle, probe transfer lines, the front half of the filter
holder, and the cyclone, if used, first, by brushing while rinsing
three times each with acetone and then, by rinsing the probe three
times with methylene chloride. Collect all the rinses in Container
No. 2.
Rinse the back half of the filter holder three times with
acetone. Rinse the connecting line between the filter and the
condenser three times with acetone. Soak the connecting line with
three separate portions of methylene chloride for 5 minutes each.
If using a separate condenser and adsorbent trap, rinse the
condenser in the same manner as the connecting line. Collect all
the rinses in Container No. 2 and mark the level of the liquid on
the container.
4.2.4 Container No. 3. Repeat the methylene chloride-rinsing
described in section 4.2.3 using toluene as the rinse solvent.
Collect the rinses in Container No. 3 and mark the level of the
liquid on the container.
4.2.5 Impinger Water. Measure the liquid in the first three
impingers to within ±1 ml by using a graduated cylinder or by
weighing it to within ±0.5 g by using a balance. Record the volume
or weight of liquid present. This information is required to
calculate the moisture content of the effluent gas.
Discard the liquid after measuring and recording the volume or
weight.
4.2.7 Silica Gel. Note the color of the indicating silica gel to
determine if it has been completely spent and make a mention of its
condition. Transfer the silica gel from the fifth impinger to its
original container and seal. If a moisture determination is made,
follow the applicable procedures in sections 8.7.6.3 and 11.2.3 of
Method 5 to handle and weigh the silica gel. If moisture is not
measured, the silica gel may be disposed.
5. Analysis
All glassware shall be cleaned as described in section 3A of the
“Manual of Analytical Methods for the Analysis of Pesticides in
Human and Environmental Samples.” All samples must be extracted
within 30 days of collection and analyzed within 45 days of
extraction.
5.1 Sample Extraction.
5.1.1 Extraction System. Place an extraction thimble (section
2.3.4), 1 g of silica gel, and a plug of glass wool into the
Soxhlet apparatus, charge the apparatus with toluene, and reflux
for a minimum of 3 hours. Remove the toluene and discard it, but
retain the silica gel. Remove the extraction thimble from the
extraction system and place it in a glass beaker to catch the
solvent rinses.
5.1.2 Container No. 1 (Filter). Transfer the contents directly
to the glass thimble of the extraction system and extract them
simultaneously with the XAD-2 resin.
5.1.3 Adsorbent Cartridge. Suspend the adsorbent module directly
over the extraction thimble in the beaker (See section 5.1.1). The
glass frit of the module should be in the up position. Using a
Teflon squeeze bottle containing toluene, flush the XAD-2 into the
thimble onto the bed of cleaned silica gel. Thoroughly rinse the
glass module catching the rinsings in the beaker containing the
thimble. If the resin is wet, effective extraction can be
accomplished by loosely packing the resin in the thimble. Add the
XAD-2 glass wool plug into the thimble.
5.1.4 Container No. 2 (Acetone and Methylene Chloride).
Concentrate the sample to a volume of about 1-5 ml using the rotary
evaporator apparatus, at a temperature of less than 37 °C. Rinse
the sample container three times with small portions of methylene
chloride and add these to the concentrated solution and concentrate
further to near dryness. This residue contains particulate matter
removed in the rinse of the train probe and nozzle. Add the
concentrate to the filter and the XAD-2 resin in the Soxhlet
apparatus described in section 5.1.1.
5.1.5 Extraction. Add 100 µl of the internal standard solution
(Section 3.3.20) to the extraction thimble containing the contents
of the adsorbent cartridge, the contents of Container No. 1, and
the concentrate from section 5.1.4. Cover the contents of the
extraction thimble with the cleaned glass wool plug to prevent the
XAD-2 resin from floating into the solvent reservoir of the
extractor. Place the thimble in the extractor, and add the toluene
contained in the beaker to the solvent reservoir. Pour additional
toluene to fill the reservoir approximately 2/3 full. Add Teflon
boiling chips and assemble the apparatus. Adjust the heat source to
cause the extractor to cycle three times per hour. Extract the
sample for 16 hours. After extraction, allow the Soxhlet to cool.
Transfer the toluene extract and three 10-ml rinses to the rotary
evaporator. Concentrate the extract to approximately 10 ml. At this
point the analyst may choose to split the sample in half. If so,
split the sample, store one half for future use, and analyze the
other according to the procedures in sections 5.2 and 5.3. In
either case, use a nitrogen evaporative concentrator to reduce the
volume of the sample being analyzed to near dryness. Dissolve the
residue in 5 ml of hexane.
5.1.6 Container No. 3 (Toluene Rinse). Add 100 µl of the
Internal Standard solution (section 3.3.2) to the contents of the
container. Concentrate the sample to a volume of about 1-5 ml using
the rotary evaporator apparatus at a temperature of less than 37
°C. Rinse the sample container apparatus at a temperature of less
than 37 °C. Rinse the sample container three times with small
portions of toluene and add these to the concentrated solution and
concentrate further to near dryness. Analyze the extract separately
according to the procedures in sections 5.2 and 5.3, but
concentrate the solution in a rotary evaporator apparatus rather
than a nitrogen evaporative concentrator.
5.2 Sample Cleanup and Fractionation.
5.2.1 Silica Gel Column. Pack one end of a glass column, 20 mm ×
230 mm, with glass wool. Add in sequence, 1 g silica gel, 2 g of
sodium hydroxide impregnated silica gel, 1 g silica gel, 4 g of
acid-modified silica gel, and 1 g of silica gel. Wash the column
with 30 ml of hexane and discard it. Add the sample extract,
dissolved in 5 ml of hexane to the column with two additional 5-ml
rinses. Elute the column with an additional 90 ml of hexane and
retain the entire eluate. Concentrate this solution to a volume of
about 1 ml using the nitrogen evaporative concentrator (section
2.3.7).
5.2.2 Basic Alumina Column. Shorten a 25-ml disposable Pasteur
pipette to about 16 ml. Pack the lower section with glass wool and
12 g of basic alumina. Transfer the concentrated extract from the
silica gel column to the top of the basic alumina column and elute
the column sequentially with 120 ml of 0.5 percent methylene
chloride in hexane followed by 120 ml of 35 percent methylene
chloride in hexane. Discard the first 120 ml of eluate. Collect the
second 120 ml of eluate and concentrate it to about 0.5 ml using
the nitrogen evaporative concentrator.
5.2.3 AX-21 Carbon/Celite 545 Column. Remove the botton 0.5 in.
from the tip of a 9-ml disposable Pasteur pipette. Insert a glass
fiber filter disk in the top of the pipette 2.5 cm from the
constriction. Add sufficient carbon/celite mixture to form a 2 cm
column. Top with a glass wool plug. In some cases AX-21 carbon
fines may wash through the glass wool plug and enter the sample.
This may be prevented by adding a celite plug to the exit end of
the column. Rinse the column in sequence with 2 ml of 50 percent
benzene in ethyl acetate, 1 ml of 50 percent methylene chloride in
cyclohexane, and 2 ml of hexane. Discard these rinses. Transfer the
concentrate in 1 ml of hexane from the basic alumina column to the
carbon/celite column along with 1 ml of hexane rinse. Elute the
column sequentially with 2 ml of 50 percent methylene chloride in
hexane and 2 ml of 50 percent benzene in ethyl acetate and discard
these eluates. Invert the column and elute in the reverse direction
with 13 ml of toluene. Collect this eluate. Concentrate the eluate
in a rotary evaporator at 50 °C to about 1 ml. Transfer the
concentrate to a Reacti-vial using a toluene rinse and concentrate
to a volume of 200 µl using a stream of N2. Store extracts at room
temperature, shielded from light, until the analysis is
performed.
5.3 Analysis. Analyze the sample with a gas chromatograph
coupled to a mass spectrometer (GC/MS) using the instrumental
parameters in sections 5.3.1 and 5.3.2. Immediately prior to
analysis, add a 20 µl aliquot of the Recovery Standard solution
from Table 1 to each sample. A 2 µl aliquot of the extract is
injected into the GC. Sample extracts are first analyzed using the
DB-5 capillary column to determine the concentration of each isomer
of PCDD's and PCDF's (tetra-through octa-). If tetra-chlorinated
dibenzofurans are detected in this analysis, then analyze another
aliquot of the sample in a separate run, using the DB-225 column to
measure the 2,3,7,8 tetra-chloro dibenzofuran isomer. Other column
systems may be used, provided that the user is able to demonstrate
using calibration and performance checks that the column system is
able to meet the specifications of section 6.1.2.2.
5.3.1 Gas Chromatograph Operating Conditions.
5.3.1.1 Injector. Configured for capillary column, splitless,
250 °C.
5.3.1.2 Carrier Gas. Helium, 1-2 ml/min.
5.3.1.3 Oven. Initially at 150 °C. Raise by at least 40 °C/min
to 190 °C and then at 3 °C/min up to 300 °C.
5.3.2 High Resolution Mass Spectrometer.
5.3.2.1 Resolution. 10000 m/e.
5.3.2.2 Ionization Mode. Electron impact.
5.3.2.3 Source Temperature 250 °C.
5.3.2.4 Monitoring Mode. Selected ion monitoring. A list of the
various ions to be monitored is summarized in Table 3.
5.3.2.5 Identification Criteria. The following identification
criteria shall be used for the characterization of polychlorinated
dibenzodioxins and dibenzofurans.
1. The integrated ion-abundance ratio (M/M + 2 or M + 2/M + 4)
shall be within 15 percent of the theoretical value. The acceptable
ion-abundance ratio ranges for the identification of
chlorine-containing compounds are given in Table 4.
2. The retention time for the analytes must be within 3 seconds
of the corresponding 1 3 C-labeled internal standard, surrogate or
alternate standard.
3. The monitored ions, shown in Table 3 for a given analyte,
shall reach their maximum within 2 seconds of each other.
4. The identification of specific isomers that do not have
corresponding 1 3 C-labeled standards is done by comparison of the
relative retention time (RRT) of the analyte to the nearest
internal standard retention time with reference (i.e., within 0.005
RRT units) to the comparable RRT's found in the continuing
calibration.
5. The signal to noise ratio for all monitored ions must be
greater than 2.5.
6. The confirmation of 2, 3, 7, 8-TCDD and 2, 3, 7, 8-TCDF shall
satisfy all of the above identification criteria.
7. For the identification of PCDF's, no signal may be found in
the corresponding PCDPE channels.
5.3.2.6 Quantification. The peak areas for the two ions
monitored for each analyte are summed to yield the total response
for each analyte. Each internal standard is used to quantify the
indigenous PCDD's or PCDF's in its homologous series. For example,
the 1 3 C 12-2,3,7,8-tetra chlorinated dibenzodioxin is used to
calculate the concentrations of all other tetra chlorinated
isomers. Recoveries of the tetra- and penta- internal standards are
calculated using the 1 3 C 12-1,2,3,4-TCDD. Recoveries of the hexa-
through octa- internal standards are calculated using 1 3 C
12-1,2,3,7,8,9-HxCDD. Recoveries of the surrogate standards are
calculated using the corresponding homolog from the internal
standard.
6. Calibration
Same as Method 5 with the following additions.
6.1 GC/MS System.
6.1.1 Initial Calibration. Calibrate the GC/MS system using the
set of five standards shown in Table 2. The relative standard
deviation for the mean response factor from each of the unlabeled
analytes (Table 2) and of the internal, surrogate, and alternate
standards shall be less than or equal to the values in Table 5. The
signal to noise ratio for the GC signal present in every selected
ion current profile shall be greater than or equal to 2.5. The ion
abundance ratios shall be within the control limits in Table 4.
6.1.2 Daily Performance Check.
6.1.2.1 Calibration Check. Inject on µl of solution Number 3
from Table 2. Calculate the relative response factor (RRF) for each
compound and compare each RRF to the corresponding mean RRF
obtained during the initial calibration. The analyzer performance
is acceptable if the measured RRF's for the labeled and unlabeled
compounds for the daily run are within the limits of the mean
values shown in Table 5. In addition, the ion-abundance ratios
shall be within the allowable control limits shown in Table 4.
6.1.2.2 Column Separation Check. Inject a solution of a mixture
of PCDD's and PCDF's that documents resolution between 2,3,7,8-TCDD
and other TCDD isomers. Resolution is defined as a valley between
peaks that is less than 25 percent of the lower of the two peaks.
Identify and record the retention time windows for each homologous
series.
Perform a similar resolution check on the confirmation column to
document the resolution between 2,3,7,8 TCDF and other TCDF
isomers.
6.2 Lock Channels. Set mass spectrometer lock channels as
specified in Table 3. Monitor the quality control check channels
specified in Table 3 to verify instrument stability during the
analysis.
7. Quality Control
7.1 Sampling Train Collection Efficiency Check. Add 100 µl of
the surrogate standards in Table 1 to the absorbent cartridge of
each train before collecting the field samples.
7.2 Internal Standard Percent Recoveries. A group of nine carbon
labeled PCDD's and PCDF's representing, the tetra-through
octachlorinated homologues, is added to every sample prior to
extraction. The role of the internal standards is to quantify the
native PCDD's and PCDF's present in the sample as well as to
determine the overall method efficiency. Recoveries of the internal
standards must be between 40 to 130 percent for the tetra-through
hexachlorinated compounds while the range is 25 to 130 percent for
the higher hepta- and octachlorinated homologues.
7.3 Surrogate Recoveries. The five surrogate compounds in Table
2 are added to the resin in the adsorbent sampling cartridge before
the sample is collected. The surrogate recoveries are measured
relative to the internal standards and are a measure of collection
efficiency. They are not used to measure native PCDD's and PCDF's.
All recoveries shall be between 70 and 130 percent. Poor recoveries
for all the surrogates may be an indication of breakthrough in the
sampling train. If the recovery of all standards is below 70
percent, the sampling runs must be repeated. As an alternative, the
sampling runs do not have to be repeated if the final results are
divided by the fraction of surrogate recovery. Poor recoveries of
isolated surrogate compounds should not be grounds for rejecting an
entire set of the samples.
7.4 Toluene QA Rinse. Report the results of the toluene QA rinse
separately from the total sample catch. Do not add it to the total
sample.
8.0 [Reserved] 9. Calculations
Same as Method 5, section 6 with the following additions.
9.1 Nomenclature.
Aai = Integrated ion current of the noise at the retention time of
the analyte. A*ci = Integrated ion current of the two ions
characteristic of the internal standard i in the calibration
standard. Acij = Integrated ion current of the two ions
characteristic of compound i in the jth calibration standard. A*cij
= Integrated ion current of the two ions characteristic of the
internal standard i in the jth calibration standard. Acsi =
Integrated ion current of the two ions characteristic of surrogate
compound i in the calibration standard. Ai = Integrated ion current
of the two ions characteristic of compound i in the sample. A*i =
Integrated ion current of the two ions characteristic of internal
standard i in the sample. Ars = Integrated ion current of the two
ions characteristic of the recovery standard. Asi = Integrated ion
current of the two ions characteristic of surrogate compound i in
the sample. Ci = Concentration of PCDD or PCDF i in the sample,
pg/M 3. CT = Total concentration of PCDD's or PCDF's in the sample,
pg/M 3. mci = Mass of compound i in the calibration standard
injected into the analyzer, pg. mrs = Mass of recovery standard in
the calibration standard injected into the analyzer, pg. msi = Mass
of surrogate compound in the calibration standard, pg. RRFi =
Relative response factor. RRFrs = Recovery standard response
factor. RRFs = Surrogate compound response factor.
9.2 Average Relative Response Factor.
9.3 Concentration of the PCDD's and PCDF's.
9.4 Recovery Standard Response Factor.
9.5 Recovery of Internal Standards (R*).
9.6 Surrogate Compound Response Factor.
9.7 Recovery of Surrogate Compounds (Rs).
9.8 Minimum Detectable Limit (MDL).
9.9 Total Concentration of PCDD's and PCDF's in the Sample.
Any PCDD's or PCDF's that are reported as nondetected (below the
MDL) shall be counted as zero for the purpose of calculating the
total concentration of PCDD's and PCDF's in the sample.
10. Bibliography
1. American Society of Mechanical Engineers. Sampling for the
Determination of Chlorinated Organic Compounds in Stack Emissions.
Prepared for U.S. Department of Energy and U.S. Environmental
Protection Agency. Washington DC. December 1984. 25 p.
2. American Society of Mechanical Engineers. Analytical
Procedures to Assay Stack Effluent Samples and Residual Combustion
Products for Polychlorinated Dibenzo-p-Dioxins (PCDD) and
Polychlorinated Dibenzofurans (PCDF). Prepared for the U.S.
Department of Energy and U.S. Environmental Protection Agency.
Washington, DC. December 1984. 23 p.
3. Thompson, J. R. (ed.). Analysis of Pesticide Residues in
Human and Environmental Samples. U.S. Environmental Protection
Agency. Research Triangle Park, NC. 1974.
4. Triangle Laboratories. Case Study: Analysis of Samples for
the Presence of Tetra Through Octachloro-p-Dibenzodioxins and
Dibenzofurans. Research Triangle Park, NC. 1988. 26 p.
5. U.S. Environmental Protection Agency. Method 8290 - The
Analysis of Polychlorinated Dibenzo-p-dioxin and Polychlorinated
Dibenzofurans by High-Resolution Gas Chromotography/High-Resolution
Mass Spectrometry. In: Test Methods for Evaluating Solid Waste.
Washington, DC. SW-846.
Table 1 - Composition of the Sample
Fortification and Recovery Standards Solutions
Analyte
Concentration (pg/µl)
Internal
Standards:
13
C12-2,3,7,8-TCDD
100
13
C12-1,2,3,7,8-PeCDD
100
13
C12-1,2,3,6,7,8-HxCDD
100
13
C12-1,2,3,4,6,7,8-HpCDD
100
13
C12-OCDD
100
13
C12-2,3,7,8-TCDF
100
13
C12-1,2,3,7,8-PeCDF
100
13
C12-1,2,3,6,7,8-HxCDF
100
13
C12-1,2,3,4,6,7,8-HpCDF
100
Surrogate
Standards:
37
Cl4-2,3,7,8-TCDD
100
13
C12-1,2,3,4,7,8-HxCDD
100
13
C12-2,3,4,7,8-PeCDF
100
13
C12-1,2,3,4,7,8-HxCDF
100
13
C12-1,2,3,4,7,8,9-HpCDF
100
Recovery
Standards:
13
C12-1,2,3,4-TCDD
500
13
C12-1,2,3,7,8,9-HxCDD
500
Table 2 - Composition of the Initial
Calibration Solutions
Compound
Concentrations
(pg/µL)
Solution No.
1
2
3
4
5
Alternate
Standard:
13
C12-1,2,3,7,8,9-HxCDF
2.5
5
25
250
500
Recovery
Standards:
13
C12-1,2,3,4-TCDD
100
100
100
100
100
13
C12-1,2,3,7,8,9-HxCDD
100
100
100
100
100
Table 3 - Elemental Compositions and Exact
Masses of the Ions Monitored by High Resolution Mass Spectrometry
for PCDD's and PCDF's
Descriptor No.
Accurate mass
Ion type
Elemental composition
Analyte
2
292.9825
LOCK
C7F11
PFK
303.9016
M
C12H4 35Cl4O
TCDF
305.8987
M + 2
C12H4 35Cl
37O
TCDF
315.9419
M
13C12H4
35Cl4O
TCDF (S)
317.9389
M + 2
13C12H4
35Cl3 37ClO
TCDF (S)
319.8965
M
C12H4 35ClO2
TCDD
321.8936
M + 2
C12H4 35Cl3
37ClO2
TCDD
327.8847
M
C12H4 37Cl4O2
TCDD (S)
330.9792
QC
C7F13
PFK
331.9368
M
13C12H4
35Cl4O2
TCDD (S)
333.9339
M + 2
13C12H4
35Cl 37ClO2
TCDD (S)
339.8597
M + 2
C12H3 35Cl4
37ClO
PECDF
341.8567
M + 4
C12H3 35Cl3
37Cl2O
PeCDF
351.9000
M + 2
13C12H3
35Cl4 37ClO
PeCDF (S)
353.8970
M + 4
13C12H3
35Cl 3537Cl2O
PeCDF (S)
355.8546
M + 2
C12H3
35Cl337ClO2
PeCDD
357.8516
M + 4
C12H3 35Cl3
37Cl2O2
PeCDD
367.8949
M + 2
13C12H3
35Cl4 37ClO2
PeCDD (S)
369.8919
M + 4
13C12H3
35Cl3 37 Cl2O2
PeCDD (S)
375.8364
M + 2
C12H4 35Cl5
37ClO
HxCDPE
409.7974
M + 2
C12H3 35Cl6
37ClO
HpCPDE
3
373.8208
M + 2
C12H235Cl5
37ClO
HxCDF
375.8178
M + 4
C12H2 35Cl4
37Cl2O
HxCDF
383.8639
M
13C12H2
35Cl6O
HxCDF (S)
385.8610
M + 2
13C12H2
35Cl5 37ClO
HxCDF (S)
389.8157
M + 2
C12H2 35Cl5
37ClO2
HxCDD
391.8127
M + 4
C12H2 35Cl4
37Cl2O2
HxCDD
392.9760
LOCK
C9F15
PFK
401.8559
M + 2
13C12H2
35Cl5 37ClO2
HxCDD (S)
403.8529
M + 4
13C12H2
35Cl4 37Cl2O
HxCDD (S)
445.7555
M + 4
C12H2 35Cl6
37Cl2O
OCDPE
430.9729
QC
C9F17
PFK
4
407.7818
M + 2
C12H 35Cl6
37ClO
HpCDF
409.7789
M + 4
C12H 35Cl5
37Cl2O
HpCDF
417.8253
M
13C12H
35Cl7O
HpCDF (S)
419.8220
M + 2
13C12H
35Cl6 37ClO
HpCDF (S)
423.7766
M + 2
C12H 35Cl6
37ClO2
HpCDD
425.7737
M + 4
C12H 35Cl5
37Cl2O2
HpCDD
435.8169
M + 2
13C12H
35Cl6 37ClO2
HpCDD (S)
437.8140
M + 4
13C12H
35Cl5 37Cl2O2
HpCDD (S)
479.7165
M + 4
C12H 35Cl7
37Cl2O
NCPDE
430.9729
LOCK
C9F17
PFK
441.7428
M + 2
C12 35Cl7
37ClO
OCDF
443.7399
M + 4
C12 35Cl6
37Cl2O
OCDF
457.7377
M + 2
C12 35Cl7
37ClO2
OCDD
459.7348
M + 4
C12 35Cl6
37Cl2O2
OCDD
469.7779
M + 2
13C12
35Cl7 37ClO2
OCDD (S)
471.7750
M + 4
13C12
35Cl6 37Cl2O2
OCDD (S)
513.6775
M + 4
C12 35Cl8
37Cl2O2
DCDPE
442.9728
QC
C10F17
PFK
(a) The following nuclidic masses were
used:
H = 1.007825
C = 12.000000
13C = 13.003355
F = 18.9984
O = 15.994915
35Cl = 34.968853
37Cl = 36.965903
S = Labeled Standard
QC = Ion selected for monitoring instrument
stability during the GC/MS analysis.
Table 4 - Acceptable Ranges for
Ion-Abundance Ratios of PCDD's and PCDF's
No. of chlorine
atoms
Ion type
Theoretical
ratio
Control
limits
Lower
Upper
4
M/M + 2
0.77
0.65
0.89
5
M + 2/M + 4
1.55
1.32
1.78
6
M + 2/M + 4
1.24
1.05
1.43
6
a
M/M + 2
0.51
0.43
0.59
7
b
M/M + 2
0.44
0.37
0.51
7
M + 2/M + 4
1.04
0.88
1.20
8
M + 2/M + 4
0.89
0.76
1.02
a Used only for
13C-HxCDF.
b Used only for
13C-HpCDF.
Table 5 - Minimum Requirements for Initial
and Daily Calibration Response Factors
Compound
Relative response
factors
Initial calibration RSD
Daily calibration %
difference
Unlabeled
Analytes:
2,3,7,8-TCDD
25
25
2,3,7,8-TCDF
25
25
1,2,3,7,8-PeCDD
25
25
1,2,3,7,8-PeCDF
25
25
2,3,4,7,8-PeCDF
25
25
1,2,4,5,7,8-HxCDD
25
25
1,2,3,6,7,8-HxCDD
25
25
1,2,3,7,8,9-HxCDD
25
25
1,2,3,4,7,8-HxCDF
25
25
1,2,3,6,7,8-HxCDF
25
25
1,2,3,7,8,9-HxCDF
25
25
2,3,4,6,7,8-HxCDF
25
25
1,2,3,4,6,7,8-HpCDD
25
25
1,2,3,4,6,7,8-HpCDF
25
25
OCDD
25
25
OCDF
30
30
Internal
Standards:
13C12-2,3,7,8-TCDD
25
25
13C12-1,2,3,7,8-PeCDD
30
30
13C12-1,2,3,6,7,8-HxCDD
25
25
13C12-1,2,3,4,6,7,8-HpCDD
30
30
13C12-OCDD
30
30
13C12-2,3,7,8-TCDF
30
30
13C12-1,2,3,7,8-PeCDF
30
30
13C12-1,2,3,6,7,8-HxCDF
30
30
13C12-1,2,3,4,6,7,8-HpCDF
30
30
Surrogate
Standards:
37Cl4-2,3,7,8-TCDD
25
25
13C12-2,3,4,7,8-PeCDF
25
25
13C12-1,2,3,4,7,8-HxCDD
25
25
13C12-1,2,3,4,7,8-HxCDF
25
25
13C12-1,2,3,4,7,8,9-HpCDF
25
25
Alternate
Standard:
13C12-1,2,3,7,8,9-HxCDF
25
25
Method 24 - Determination of Volatile Matter Content, Water
Content, Density, Volume Solids, and Weight Solids of Surface
Coatings 1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Volatile organic
compounds Water
No CAS Number assigned
7732-18-5
1.2 Applicability. This method is applicable for the
determination of volatile matter content, water content, density,
volume solids, and weight solids of paint, varnish, lacquer, or
other related surface coatings.
1.3 Precision and Bias. Intra-and inter-laboratory analytical
precision statements are presented in section 13.1. No bias has
been identified.
2.0 Summary of Method
2.1 Standard methods are used to determine the volatile matter
content, water content, density, volume solids, and weight solids
of paint, varnish, lacquer, or other related surface coatings.
3.0 Definitions
3.1 Waterborne coating means any coating which contains
more than 5 percent water by weight in its volatile fraction.
3.2 Multicomponent coatings are coatings that are
packaged in two or more parts, which are combined before
application. Upon combination a coreactant from one part of the
coating chemically reacts, at ambient conditions, with a coreactant
from another part of the coating.
3.3 Ultraviolet (UV) radiation-cured coatings are
coatings which contain unreacted monomers that are polymerized by
exposure to ultraviolet light.
4.0 Interferences [Reserved] 5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Hazardous Components. Several of the compounds that may be
contained in the coatings analyzed by this method may be irritating
or corrosive to tissues (e.g., heptane) or may be toxic (e.g.,
benzene, methyl alcohol). Nearly all are fire hazards. Appropriate
precautions can be found in reference documents, such as Reference
3 of section 16.0.
6.0 Equipment and Supplies
The equipment and supplies specified in the ASTM methods listed
in sections 6.1 through 6.6 (incorporated by reference - see §
60.17 for acceptable versions of the methods) are required:
6.1 ASTM D 1475-60, 80, or 90, Standard Test Method for Density
of Paint, Varnish, Lacquer, and Related Products.
6.2 ASTM D 2369-81, 87, 90, 92, 93, 95, or 10. Standard Test
Method for Volatile Content of Coatings.
6.3 ASTM D 3792-79 or 91, Standard Test Method for Water Content
of Water Reducible Paints by Direct Injection into a Gas
Chromatograph.
6.4 ASTM D 4017-81, 90, or 96a, Standard Test Method for Water
in Paints and Paint Materials by the Karl Fischer Titration
Method.
6.5 ASTM 4457-85 91, Standard Test Method for Determination of
Dichloromethane and 1,1,1-Trichloroethane in Paints and Coatings by
Direct Injection into a Gas Chromatograph.
6.6 ASTM D 5403-93, Standard Test Methods for Volatile Content
of Radiation Curable Materials.
6.7 ASTM D 6419-00, Test Method for Volatile Content of
Sheet-Fed and Coldset Web Offset Printing Inks.
7.0 Reagents and Standards
7.1 The reagents and standards specified in the ASTM methods
listed in sections 6.1 through 6.6 are required.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Follow the sample collection, preservation, storage, and
transport procedures described in Reference 1 of section 16.0.
9.0 Quality Control
9.1 Reproducibility
Note:
Not applicable to UV radiation-cured coatings). The variety of
coatings that may be subject to analysis makes it necessary to
verify the ability of the analyst and the analytical procedures to
obtain reproducible results for the coatings tested. Verification
is accomplished by running duplicate analyses on each sample tested
(Sections 11.2 through 11.4) and comparing the results with the
intra-laboratory precision statements (Section 13.1) for each
parameter.
9.2 Confidence Limits for Waterborne Coatings. Because of the
inherent increased imprecision in the determination of the VOC
content of waterborne coatings as the weight percent of water
increases, measured parameters for waterborne coatings are replaced
with appropriate confidence limits (Section 12.6). These confidence
limits are based on measured parameters and inter-laboratory
precision statements.
10.0 Calibration and Standardization
10.1 Perform the calibration and standardization procedures
specified in the ASTM methods listed in sections 6.1 through
6.6.
11.0 Analytical Procedure
Additional guidance can be found in Reference 2 of section
16.0.
11.1 Non Thin-film Ultraviolet Radiation-cured (UV
radiation-cured) Coatings.
11.1.1 Volatile Content. Use the procedure in ASTM D 5403 to
determine the volatile matter content of the coating except the
curing test described in NOTE 2 of ASTM D 5403 is required.
11.1.2 Water Content. To determine water content, follow section
11.3.2.
11.1.3 Coating Density. To determine coating density, follow
section 11.3.3.
11.1.4 Solids Content. To determine solids content, follow
section 11.3.4.
11.1.5 To determine if a coating or ink can be classified as a
thin-film UV cured coating or ink, use the equation in section
12.2. If C is less than 0.2 g and A is greater than or equal to 225
cm 2 (35 in 2) then the coating or ink is considered a thin-film UV
radiation-cured coating and ASTM D 5403 is not applicable.
Note:
As noted in section 1.4 of ASTM D 5403, this method may not be
applicable to radiation curable materials wherein the volatile
material is water.
11.2 Multi-component Coatings.
11.2.1 Sample Preparation.
11.2.1.1 Prepare about 100 ml of sample by mixing the components
in a storage container, such as a glass jar with a screw top or a
metal can with a cap. The storage container should be just large
enough to hold the mixture. Combine the components (by weight or
volume) in the ratio recommended by the manufacturer. Tightly close
the container between additions and during mixing to prevent loss
of volatile materials. However, most manufacturers mixing
instructions are by volume. Because of possible error caused by
expansion of the liquid when measuring the volume, it is
recommended that the components be combined by weight. When weight
is used to combine the components and the manufacturer's
recommended ratio is by volume, the density must be determined by
section 11.3.3.
11.2.1.2 Immediately after mixing, take aliquots from this 100
ml sample for determination of the total volatile content, water
content, and density.
11.2.2 Volatile Content. To determine total volatile content,
use the apparatus and reagents described in ASTM D2369
(incorporated by reference; see § 60.17 for the approved versions
of the standard), respectively, and use the following
procedures:
11.2.2.1 Weigh and record the weight of an aluminum foil
weighing dish. Add 3 ±1 ml of suitable solvent as specified in ASTM
D2369 to the weighing dish. Using a syringe as specified in ASTM
D2369, weigh to 1 mg, by difference, a sample of coating into the
weighing dish. For coatings believed to have a volatile content
less than 40 weight percent, a suitable size is 0.3 + 0.10 g, but
for coatings believed to have a volatile content greater than 40
weight percent, a suitable size is 0.5 ±0.1 g.
Note:
If the volatile content determined pursuant to section 12.4 is
not in the range corresponding to the sample size chosen repeat the
test with the appropriate sample size. Add the specimen dropwise,
shaking (swirling) the dish to disperse the specimen completely in
the solvent. If the material forms a lump that cannot be dispersed,
discard the specimen and prepare a new one. Similarly, prepare a
duplicate. The sample shall stand for a minimum of 1 hour, but no
more than 24 hours prior to being oven cured at 110 ±5 °C (230 ±9
°F) for 1 hour.
11.2.2.2 Heat the aluminum foil dishes containing the dispersed
specimens in the forced draft oven for 60 min at 110 ±5 °C (230 ±9
°F). Caution - provide adequate ventilation, consistent with
accepted laboratory practice, to prevent solvent vapors from
accumulating to a dangerous level.
11.2.2.3 Remove the dishes from the oven, place immediately in a
desiccator, cool to ambient temperature, and weigh to within 1
mg.
11.2.2.4 Run analyses in pairs (duplicate sets) for each coating
mixture until the criterion in section 11.4 is met. Calculate WV
following Equation 24-2 and record the arithmetic average.
11.2.3 Water Content. To determine water content, follow section
11.3.2.
11.2.4 Coating Density. To determine coating density, follow
section 11.3.3.
11.2.5 Solids Content. To determine solids content, follow
section 11.3.4.
11.2.6 Exempt Solvent Content. To determine the exempt solvent
content, follow section 11.3.5.
Note:
For all other coatings (i.e., water-or solvent-borne
coatings) not covered by multicomponent or UV radiation-cured
coatings, analyze as shown below:
11.3 Water-or Solvent-borne coatings.
11.3.1 Volatile Content. Use the procedure in ASTM D 2369 to
determine the volatile matter content (may include water) of the
coating.
11.3.1.1 Record the following information:
W1 = weight of dish and sample before heating, g W2 = weight of
dish and sample after heating, g W3 = sample weight, g.
11.3.1.2 Calculate the weight fraction of the volatile matter
(Wv) for each analysis as shown in section 12.3.
11.3.1.3 Run duplicate analyses until the difference between the
two values in a set is less than or equal to the intra-laboratory
precision statement in section 13.1.
11.3.1.4 Record the arithmetic average (Wv).
11.3.2 Water Content. For waterborne coatings only, determine
the weight fraction of water (Ww) using either ASTM D 3792 or ASTM
D 4017.
11.3.2.1 Run duplicate analyses until the difference between the
two values in a set is less than or equal to the intra-laboratory
precision statement in section 13.1.
11.3.2.2 Record the arithmetic average (ww).
11.3.3 Coating Density. Determine the density (Dc, kg/l) of the
surface coating using the procedure in ASTM D 1475.
11.3.3.1 Run duplicate analyses until each value in a set
deviates from the mean of the set by no more than the
intra-laboratory precision statement in section 13.1.
11.3.3.2 Record the arithmetic average (Dc).
11.3.4 Solids Content. Determine the volume fraction (Vs) solids
of the coating by calculation using the manufacturer's
formulation.
11.3.5 Exempt Solvent Content. Determine the weight fraction of
exempt solvents (WE) by using ASTM Method D4457. Run a duplicate
set of determinations and record the arithmetic average (WE).
11.4 Sample Analysis Criteria. For Wv and Ww, run duplicate
analyses until the difference between the two values in a set is
less than or equal to the intra-laboratory precision statement for
that parameter. For Dc, run duplicate analyses until each value in
a set deviates from the mean of the set by no more than the
intra-laboratory precision statement. If, after several attempts,
it is concluded that the ASTM procedures cannot be used for the
specific coating with the established intra-laboratory precision
(excluding UV radiation-cured coatings), the U.S. Environmental
Protection Agency (EPA) will assume responsibility for providing
the necessary procedures for revising the method or precision
statements upon written request to: Director, Emissions,
Monitoring, and Analysis Division, MD-14, Office of Air Quality
Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC 27711.
12.0 Calculations and Data Analysis
12.1 Nomenclature.
A = Area of substrate, cm 2, (in 2). C = Amount of coating or ink
added to the substrate, g. Dc = Density of coating or ink, g/cm 3
(g/in 3). F = Manufacturer's recommended film thickness, cm (in).
Wo = Weight fraction of nonaqueous volatile matter, g/g. Ws =
Weight fraction of solids, g/g. Wv = Weight fraction of the
volatile matter, g/g. Ww = Weight fraction of the water, g/g.
12.2 To determine if a coating or ink can be classified as a
thin-film UV cured coating or ink, use the following equation:
12.3 Calculate Wv for each analysis as shown below:
12.4 Nonaqueous Volatile Matter.
12.4.1 Solvent-borne Coatings.
12.4.2 Waterborne Coatings.
12.4.3 Coatings Containing Exempt Solvents.
12.5 Weight Fraction Solids.
12.6 Confidence Limit Calculations for Waterborne Coatings. To
calculate the lower confidence limit, subtract the appropriate
inter-laboratory precision value from the measured mean value for
that parameter. To calculate the upper confidence limit, add the
appropriate inter-laboratory precision value to the measured mean
value for that parameter. For Wv and Dc, use the lower confidence
limits; for Ww, use the upper confidence limit. Because Ws is
calculated, there is no adjustment for this parameter.
13.0 Method Performance
13.1 Analytical Precision Statements. The intra-and
inter-laboratory precision statements are given in Table 24-1 in
section 17.0.
Same as specified in section 6.0, with the addition of the
following:
1. Standard Procedure for Collection of Coating and Ink Samples
for Analysis by Reference Methods 24 and 24A. EPA-340/1-91-010.
U.S. Environmental Protection Agency, Stationary Source Compliance
Division, Washington, D.C. September 1991.
2. Standard Operating Procedure for Analysis of Coating and Ink
Samples by Reference Methods 24 and 24A.
EPA-340/1-91-011. U.S. Environmental Protection Agency,
Stationary Source Compliance Division, Washington, D.C. September
1991.
3. Handbook of Hazardous Materials: Fire, Safety, Health.
Alliance of American Insurers. Schaumberg, IL. 1983.
17.0 Tables, Diagrams, Flowcharts, and Validation Data
Table 24-1 - Analytical Precision
Statements
Intra-laboratory
Inter-laboratory
Volatile matter
content, Wv
±0.015 Wv
±0.047 W v
Water content,
Ww
±0.029 W w
±0.075 Ww
Density, Dc
±0.001 kg/l
±0.002 kg/l
Method 24A - Determination of Volatile Matter Content and Density
of Publication Rotogravure Inks and Related Publication Rotogravure
Coatings 1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Volatile organic
compounds (VOC)
No CAS number assigned.
1.2 Applicability. This method is applicable for the
determination of the VOC content and density of solvent-borne
(solvent-reducible) publication rotogravure inks and related
publication rotogravure coatings.
2.0 Summary of Method
2.1 Separate procedures are used to determine the VOC weight
fraction and density of the ink or related coating and the density
of the solvent in the ink or related coating. The VOC weight
fraction is determined by measuring the weight loss of a known
sample quantity which has been heated for a specified length of
time at a specified temperature. The density of both the ink or
related coating and solvent are measured by a standard procedure.
From this information, the VOC volume fraction is calculated.
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method does not purport to
address all of the safety problems associated with its use. It is
the responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Hazardous Components. Some of the compounds that may be
contained in the inks or related coatings analyzed by this method
may be irritating or corrosive to tissues or may be toxic. Nearly
all are fire hazards. Appropriate precautions can be found in
reference documents, such as Reference 6 of section 16.0.
6.0 Equipment and Supplies
The following equipment and supplies are required for sample
analysis:
6.1 Weighing Dishes. Aluminum foil, 58 mm (2.3 in.) in diameter
by 18 mm (0.7 in.) high, with a flat bottom. There must be at least
three weighing dishes per sample.
6.2 Disposable Syringe. 5 ml.
6.3 Analytical Balance. To measure to within 0.1 mg.
6.4 Oven. Vacuum oven capable of maintaining a temperature of
120 ±2 °C (248 ±4 °F) and an absolute pressure of 510 ±51 mm Hg (20
±2 in. Hg) for 4 hours. Alternatively, a forced draft oven capable
of maintaining a temperature of 120 ±2 °C (248 ±4 °F) for 24
hours.
6.5 The equipment and supplies specified in ASTM D 1475-60, 80,
or 90 (incorporated by reference - see § 60.17).
7.0 Reagents and Standards
7.1 The reagents and standards specified in ASTM D 1475-60, 80,
or 90 are required.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Follow the sample collection, preservation, storage, and
transport procedures described in Reference 4 of section 16.0.
9.0 Quality Control [Reserved] 10.0 Calibration and Standardization
[Reserved] 11.0 Analytical Procedure
Additional guidance can be found in Reference 5 of section
16.0.
11.1 VOC Weight Fraction. Shake or mix the ink or related
coating sample thoroughly to assure that all the solids are
completely suspended. Label and weigh to the nearest 0.1 mg a
weighing dish and record this weight (Mx1). Using a 5 ml syringe,
without a needle, extract an aliquot from the ink or related
coating sample. Weigh the syringe and aliquot to the nearest 0.1 mg
and record this weight (Mcy1). Transfer 1 to 3 g of the aliquot to
the tared weighing dish. Reweigh the syringe and remaining aliquot
to the nearest 0.1 mg and record this weight (Mcy2). Heat the
weighing dish with the transferred aliquot in a vacuum oven at an
absolute pressure of 510 ±51 mm Hg (20 ±2 in. Hg) and a temperature
of 120 ±2 °C (248 ±4 °F) for 4 hours. Alternatively, heat the
weighing dish with the transferred aliquot in a forced draft oven
at a temperature of 120 ±2 °C for 24 hours. After the weighing dish
has cooled, reweigh it to the nearest 0.1 mg and record the weight
(Mx2). Repeat this procedure two times for each ink or related
coating sample, for a total of three samples.
11.2 Ink or Related Coating Density. Determine the density of
the ink or related coating (Dc) according to the procedure outlined
in ASTM D 1475. Make a total of three determinations for each ink
or related coating sample. Report the ink or related coating
density as the arithmetic average (Dc) of the three
determinations.
11.3 Solvent Density. Determine the density of the solvent (Do)
according to the procedure outlined in ASTM D 1475. Make a total of
three determinations for each ink or related coating sample. Report
the solvent density as the arithmetic average (Do) of the three
determinations.
12.0 Calculations and Data Analysis
12.1 VOC Weight Fraction. For each determination, calculate the
volatile organic content weight fraction (Wo) using the following
equation:
Make a total of three determinations. Report
the VOC weight fraction as the arithmetic average (W o) of the
three determinations.
12.2 VOC Volume Fraction. Calculate the volume fraction volatile
organic content (Vo) using the following equation:
1. Standard Test Method for Density of Paint, Varnish, Lacquer,
and Related Products. ASTM Designation D 1475.
2. Teleconversation. Wright, Chuck, Inmont Corporation with
Reich, R., A., Radian Corporation. September 25, 1979, Gravure Ink
Analysis.
3. Teleconversation. Oppenheimer, Robert, Gravure Research
Institute with Burt, Rick, Radian Corporation, November 5, 1979,
Gravure Ink Analysis.
4. Standard Procedure for Collection of Coating and Ink Samples
for Analysis by Reference Methods 24 and 24A. EPA-340/1-91-010.
U.S. Environmental Protection Agency, Stationary Source Compliance
Division, Washington, D.C. September 1991.
5. Standard Operating Procedure for Analysis of Coating and Ink
Samples by Reference Methods 24 and 24A. EPA-340/1-91-011. U.S.
Environmental Protection Agency, Stationary Source Compliance
Division, Washington, D.C. September 1991.
6. Handbook of Hazardous Materials: Fire, Safety, Health.
Alliance of American Insurers. Schaumberg, IL. 1983.
17.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
Method 25 - Determination of Total Gaseous Nonmethane Organic
Emissions as Carbon 1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Total gaseous
nonmethane organic compounds (TGNMO)
N/A
Dependent upon analytical
equipment.
1.2 Applicability.
1.2.1 This method is applicable for the determination of
volatile organic compounds (VOC) (measured as total gaseous
nonmethane organics (TGNMO) and reported as carbon) in stationary
source emissions. This method is not applicable for the
determination of organic particulate matter.
1.2.2 This method is not the only method that applies to the
measurement of VOC. Costs, logistics, and other practicalities of
source testing may make other test methods more desirable for
measuring VOC contents of certain effluent streams. Proper judgment
is required in determining the most applicable VOC test method. For
example, depending upon the molecular composition of the organics
in the effluent stream, a totally automated semicontinuous
nonmethane organics (NMO) analyzer interfaced directly to the
source may yield accurate results. This approach has the advantage
of providing emission data semicontinuously over an extended time
period.
1.2.3 Direct measurement of an effluent with a flame ionization
detector (FID) analyzer may be appropriate with prior
characterization of the gas stream and knowledge that the detector
responds predictably to the organic compounds in the stream. If
present, methane (CH4) will, of course, also be measured. The FID
can be used under any of the following limited conditions: (1)
Where only one compound is known to exist; (2) when the organic
compounds consist of only hydrogen and carbon; (3) where the
relative percentages of the compounds are known or can be
determined, and the FID responses to the compounds are known; (4)
where a consistent mixture of the compounds exists before and after
emission control and only the relative concentrations are to be
assessed; or (5) where the FID can be calibrated against mass
standards of the compounds emitted (solvent emissions, for
example).
1.2.4 Another example of the use of a direct FID is as a
screening method. If there is enough information available to
provide a rough estimate of the analyzer accuracy, the FID analyzer
can be used to determine the VOC content of an uncharacterized gas
stream. With a sufficient buffer to account for possible
inaccuracies, the direct FID can be a useful tool to obtain the
desired results without costly exact determination.
1.2.5 In situations where a qualitative/quantitative analysis of
an effluent stream is desired or required, a gas chromatographic
FID system may apply. However, for sources emitting numerous
organics, the time and expense of this approach will be
formidable.
2.0 Summary of Method
2.1 An emission sample is withdrawn from the stack at a constant
rate through a heated filter and a chilled condensate trap by means
of an evacuated sample tank. After sampling is completed, the TGNMO
are determined by independently analyzing the condensate trap and
sample tank fractions and combining the analytical results. The
organic content of the condensate trap fraction is determined by
oxidizing the NMO to carbon dioxide (CO2) and quantitatively
collecting in the effluent in an evacuated vessel; then a portion
of the CO2 is reduced to CH4 and measured by an FID. The organic
content of the sample tank fraction is measured by injecting a
portion of the sample into a gas chromatographic column to separate
the NMO from carbon monoxide (CO), CO2, and CH4; the NMO are
oxidized to CO2, reduced to CH4, and measured by an FID. In this
manner, the variable response of the FID associated with different
types of organics is eliminated.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Carbon Dioxide and Water Vapor. When carbon dioxide (CO2)
and water vapor are present together in the stack, they can produce
a positive bias in the sample. The magnitude of the bias depends on
the concentrations of CO2 and water vapor. As a guideline, multiply
the CO2 concentration, expressed as volume percent, times the water
vapor concentration. If this product does not exceed 100, the bias
can be considered insignificant. For example, the bias is not
significant for a source having 10 percent CO2 and 10 percent water
vapor, but it might be significant for a source having 10 percent
CO2 and 20 percent water vapor.
4.2. Particulate Matter. Collection of organic particulate
matter in the condensate trap would produce a positive bias. A
filter is included in the sampling equipment to minimize this
bias.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies
6.1 Sample Collection. The sampling system consists of a heated
probe, heated filter, condensate trap, flow control system, and
sample tank (see Figure 25-1). The TGNMO sampling equipment can be
constructed from commercially available components and components
fabricated in a machine shop. The following equipment is
required:
6.1.1 Heated Probe. 6.4-mm ( 1/4-in.) OD stainless steel tubing
with a heating system capable of maintaining a gas temperature at
the exit end of at least 129 °C (265 °F). The probe shall be
equipped with a temperature sensor at the exit end to monitor the
gas temperature. A suitable probe is shown in Figure 25-1. The
nozzle is an elbow fitting attached to the front end of the probe
while the temperature sensor is inserted in the side arm of a tee
fitting attached to the rear of the probe. The probe is wrapped
with a suitable length of high temperature heating tape, and then
covered with two layers of glass cloth insulation and one layer of
aluminum foil or an equivalent wrapping.
Note:
If it is not possible to use a heating system for safety
reasons, an unheated system with an in-stack filter is a suitable
alternative.
6.1.2 Filter Holder. 25-mm ( 15/16-in.) ID Gelman filter holder
with 303 stainless steel body and 316 stainless steel support
screen with the Viton O-ring replaced by a Teflon O-ring.
6.1.3 Filter Heating System.
6.1.3.1 A metal box consisting of an inner and an outer shell
separated by insulating material with a heating element in the
inner shell capable of maintaining a gas temperature at the filter
of 121 ±3 °C (250 ±5 °F). The heating box shall include temperature
sensors to monitor the gas temperature immediately upstream and
immediately downstream of the filter.
6.1.3.2 A suitable heating box is shown in Figure 25-2. The
outer shell is a metal box that measures 102 mm × 280 mm × 292 mm
(4 in. × 11 in. × 11 1/2 in.), while the inner shell is a metal box
measuring 76 mm × 229 mm × 241 mm (3 in. × 9 in. × 9 1/2 in.). The
inner box is supported by 13-mm ( 1/2-in.) phenolic rods. The void
space between the boxes is filled with ceramic fiber insulation
which is sealed in place by means of a silicon rubber bead around
the upper sides of the box. A removable lid made in a similar
manner, with a 25-mm (1-in.) gap between the parts is used to cover
the heating chamber. The inner box is heated with a 250-watt
cartridge heater, shielded by a stainless steel shroud. The heater
is regulated by a thermostatic temperature controller which is set
to maintain a gas temperature of 121 °C (250 °F) as measured by the
temperature sensor upstream of the filter.
Note:
If it is not possible to use a heating system for safety
reasons, an unheated system with an in-stack filter is a suitable
alternative.
6.1.4 Condensate Trap. 9.5-mm ( 3/8-in.) OD 316 stainless steel
tubing bent into a U-shape. Exact dimensions are shown in Figure
25-3. The tubing shall be packed with coarse quartz wool, to a
density of approximately 0.11 g/cm 3 before bending. While the
condensate trap is packed with dry ice in the Dewar, an ice bridge
may form between the arms of the condensate trap making it
difficult to remove the condensate trap. This problem can be
prevented by attaching a steel plate between the arms of the
condensate trap in the same plane as the arms to completely fill
the intervening space.
6.1.5 Valve. Stainless steel control valve for starting and
stopping sample flow.
6.1.6 Metering Valve. Stainless steel valve for regulating the
sample flow rate through the sample train.
6.1.7 Rate Meter. Rotameter, or equivalent, capable of measuring
sample flow in the range of 60 to 100 cm 3/min (0.13 to 0.21 ft
3/hr).
6.1.8 Sample Tank. Stainless steel or aluminum tank with a
minimum volume of 4 liters (0.14 ft 3).
Note:
Sample volumes greater than 4 liters may be required for sources
with low organic concentrations.
6.1.9 Mercury Manometer. U-tube manometer or absolute pressure
gauge capable of measuring pressure to within 1 mm Hg in the range
of 0 to 900 mm.
6.1.10 Vacuum Pump. Capable of evacuating to an absolute
pressure of 10 mm Hg.
6.2 Condensate Recovery. The system for the recovery of the
organics captured in the condensate trap consists of a heat source,
an oxidation catalyst, a nondispersive infrared (NDIR) analyzer,
and an intermediate collection vessel (ICV). Figure 25-4 is a
schematic of a typical system. The system shall be capable of
proper oxidation and recovery, as specified in section 10.1.1. The
following major components are required:
6.2.1 Heat Source. Sufficient to heat the condensate trap
(including probe) to a temperature of 200 °C (390 °F). A system
using both a heat gun and an electric tube furnace is
recommended.
6.2.2 Heat Tape. Sufficient to heat the connecting tubing
between the water trap and the oxidation catalyst to 100 °C (212
°F).
6.2.3 Oxidation Catalyst. A suitable length of 9.5 mm ( 3/8-in.)
OD Inconel 600 tubing packed with 15 cm (6 in.) of 3.2 mm (
3/8-in.) diameter 19 percent chromia on alumina pellets. The
catalyst material is packed in the center of the catalyst tube with
quartz wool packed on either end to hold it in place.
6.2.4 Water Trap. Leak-proof, capable of removing moisture from
the gas stream.
6.2.5 Syringe Port. A 6.4-mm ( 1/4-in.) OD stainless steel tee
fitting with a rubber septum placed in the side arm.
6.2.6 NDIR Detector. Capable of indicating CO2 concentration in
the range of zero to 5 percent, to monitor the progress of
combustion of the organic compounds from the condensate trap.
6.2.7 Flow-Control Valve. Stainless steel, to maintain the trap
conditioning system near atmospheric pressure.
6.2.8 Intermediate Collection Vessel. Stainless steel or
aluminum, equipped with a female quick connect. Tanks with nominal
volumes of at least 6 liters (0.2 ft 3) are recommended.
6.2.9 Mercury Manometer. Same as described in section 6.1.9.
6.2.10 Syringe. 10-ml gas-tight glass syringe equipped with an
appropriate needle.
6.2.11 Syringes. 10-µl and 50-µl liquid injection syringes.
6.2.12 Liquid Sample Injection Unit. 316 Stainless steel U-tube
fitted with an injection septum (see Figure 25-7).
6.3 Analysis.
6.3.1 NMO Analyzer. The NMO analyzer is a gas chromatograph (GC)
with backflush capability for NMO analysis and is equipped with an
oxidation catalyst, reduction catalyst, and FID. Figures 25-5 and
25-6 are schematics of a typical NMO analyzer. This semicontinuous
GC/FID analyzer shall be capable of: (1) Separating CO, CO2, and
CH4 from NMO, (2) reducing the CO2 to CH4 and quantifying as CH4,
and (3) oxidizing the NMO to CO2, reducing the CO2 to CH4 and
quantifying as CH4, according to section 10.1.2. The analyzer
consists of the following major components:
6.3.1.1 Oxidation Catalyst. A suitable length of 9.5-mm (
3/8-in.) OD Inconel 600 tubing packed with 5.1 cm (2 in.) of 19
percent chromia on 3.2-mm ( 1/8-in.) alumina pellets. The catalyst
material is packed in the center of the tube supported on either
side by quartz wool. The catalyst tube must be mounted vertically
in a 650 °C (1200 °F) furnace. Longer catalysts mounted
horizontally may be used, provided they can meet the specifications
of section 10.1.2.1.
6.3.1.2 Reduction Catalyst. A 7.6-cm (3-in.) length of 6.4-mm (
1/4-in.) OD Inconel tubing fully packed with 100-mesh pure nickel
powder. The catalyst tube must be mounted vertically in a 400 °C
(750 °F) furnace.
6.3.1.3 Separation Column(s). A 30-cm (1-ft) length of 3.2-mm (
1/8-in.) OD stainless steel tubing packed with 60/80 mesh Unibeads
1S followed by a 61-cm (2-ft) length of 3.2-mm ( 1/8-in.) OD
stainless steel tubing packed with 60/80 mesh Carbosieve G. The
Carbosieve and Unibeads columns must be baked separately at 200 °C
(390 °F) with carrier gas flowing through them for 24 hours before
initial use.
6.3.1.4 Sample Injection System. A single 10-port GC sample
injection valve or a group of valves with sufficient ports fitted
with a sample loop properly sized to interface with the NMO
analyzer (1-cc loop recommended).
6.3.1.5 FID. An FID meeting the following specifications is
required:
6.3.1.5.1 Linearity. A linear response (±5 percent) over the
operating range as demonstrated by the procedures established in
section 10.1.2.3.
6.3.1.5.2 Range. A full scale range of 10 to 50,000 ppm CH4.
Signal attenuators shall be available to produce a minimum signal
response of 10 percent of full scale.
6.3.1.6 Data Recording System. Analog strip chart recorder or
digital integration system compatible with the FID for permanently
recording the analytical results.
6.3.2 Barometer. Mercury, aneroid, or other barometer capable of
measuring atmospheric pressure to within 1 mm Hg.
6.3.3 Temperature Sensor. Capable of measuring the laboratory
temperature within 1 °C (2 °F).
6.3.4 Vacuum Pump. Capable of evacuating to an absolute pressure
of 10 mm Hg.
7.0 Reagents and Standards
7.1 Sample Collection. The following reagents are required for
sample collection:
7.1.1 Dry Ice. Solid CO2, crushed.
7.1.2 Coarse Quartz Wool. 8 to 15 um.
7.1.3 Filters. Glass fiber filters, without organic binder,
exhibiting at least 99.95 percent efficiency (<0.05 percent
penetration) on 0.3 micron dioctyl phthalate smoke particles. The
filter efficiency test shall be conducted in accordance with ASTM
Method D2986-71, 78, or 95a (incorporated by reference - see §
60.17). Test data from the supplier's quality control program are
sufficient for this purpose.
7.2 NMO Analysis. The following gases are required for NMO
analysis:
7.2.1 Carrier Gases. Helium (He) and oxygen (O2) containing less
than 1 ppm CO2 and less than 0.1 ppm hydrocarbon.
7.2.2 Fuel Gas. Hydrogen (H2), at least 99.999 percent pure.
7.2.3 Combustion Gas. Either air (less than 0.1 ppm total
hydrocarbon content) or O2 (purity 99.99 percent or greater), as
required by the detector.
7.3 Condensate Analysis. The following are required for
condensate analysis:
7.3.1 Gases. Containing less than 1 ppm carbon.
7.3.1.1 Air.
7.3.1.2 Oxygen.
7.3.2 Liquids. To conform to the specifications established by
the Committee on Analytical Reagents of the American Chemical
Society.
7.3.2.1 Hexane.
7.3.2.2 Decane.
7.4 Calibration. For all calibration gases, the manufacturer
must recommend a maximum shelf life for each cylinder (i.e., the
length of time the gas concentration is not expected to change more
than ±5 percent from its certified value). The date of gas cylinder
preparation, certified organic concentration, and recommended
maximum shelf life must be affixed to each cylinder before shipment
from the gas manufacturer to the buyer. The following calibration
gases are required:
7.4.1 Oxidation Catalyst Efficiency Check Calibration Gas. Gas
mixture standard with nominal concentration of 1 percent methane in
air.
7.4.2 FID Linearity and NMO Calibration Gases. Three gas mixture
standards with nominal propane concentrations of 20 ppm, 200 ppm,
and 3000 ppm, in air.
7.4.3 CO2 Calibration Gases. Three gas mixture standards with
nominal CO2 concentrations of 50 ppm, 500 ppm, and 1 percent, in
air.
Note:
Total NMO less than 1 ppm required for 1 percent mixture.
7.4.4 NMO Analyzer System Check Calibration Gases. Four
calibration gases are needed as follows:
7.4.4.1 Propane Mixture. Gas mixture standard containing
(nominal) 50 ppm CO, 50 ppm CH4, 1 percent CO2, and 20 ppm C3H8,
prepared in air.
7.4.4.2 Hexane. Gas mixture standard containing (nominal) 50 ppm
hexane in air.
7.4.4.3 Toluene. Gas mixture standard containing (nominal) 20
ppm toluene in air.
7.4.4.4 Methanol. Gas mixture standard containing (nominal) 100
ppm methanol in air.
8.0 Sample Collection, Preservation, Transport, and Storage
8.1 Sampling Equipment Preparation.
8.1.1 Condensate Trap Cleaning. Before its initial use and after
each use, a condensate trap should be thoroughly cleaned and
checked to ensure that it is not contaminated. Both cleaning and
checking can be accomplished by installing the trap in the
condensate recovery system and treating it as if it were a sample.
The trap should be heated as described in section 11.1.3. A trap
may be considered clean when the CO2 concentration in its effluent
gas drops below 10 ppm. This check is optional for traps that most
recently have been used to collect samples which were then
recovered according to the procedure in section 11.1.3.
8.1.2 Sample Tank Evacuation and Leak-Check. Evacuate the sample
tank to 10 mm Hg absolute pressure or less. Then close the sample
tank valve, and allow the tank to sit for 60 minutes. The tank is
acceptable if a change in tank vacuum of less than 1 mm Hg is
noted. The evacuation and leak-check may be conducted either in the
laboratory or the field.
8.1.3 Sampling Train Assembly. Just before assembly, measure the
tank vacuum using a mercury manometer. Record this vacuum, the
ambient temperature, and the barometric pressure at this time.
Close the sample tank valve and assemble the sampling system as
shown in Figure 25-1. Immerse the condensate trap body in dry ice
at least 30 minutes before commencing sampling to improve
collection efficiency. The point where the inlet tube joins the
trap body should be 2.5 to 5 cm (1 to 2 in.) above the top of the
dry ice.
8.1.4 Pretest Leak-Check. A pretest leak-check is required.
Calculate or measure the approximate volume of the sampling train
from the probe tip to the sample tank valve. After assembling the
sampling train, plug the probe tip, and make certain that the
sample tank valve is closed. Turn on the vacuum pump, and evacuate
the sampling system from the probe tip to the sample tank valve to
an absolute pressure of 10 mm Hg or less. Close the purge valve,
turn off the pump, wait a minimum period of 10 minutes, and recheck
the indicated vacuum. Calculate the maximum allowable pressure
change based on a leak rate of 1 percent of the sampling rate using
Equation 25-1, section 12.2. If the measured pressure change
exceeds the allowable, correct the problem and repeat the
leak-check before beginning sampling.
8.2 Sample Collection.
8.2.1 Unplug the probe tip, and place the probe into the stack
such that the probe is perpendicular to the duct or stack axis;
locate the probe tip at a single preselected point of average
velocity facing away from the direction of gas flow. For stacks
having a negative static pressure, seal the sample port
sufficiently to prevent air in-leakage around the probe. Set the
probe temperature controller to 129 °C (265 °F) and the filter
temperature controller to 121 °C (250 °F). Allow the probe and
filter to heat for about 30 minutes before purging the sample
train.
8.2.2 Close the sample valve, open the purge valve, and start
the vacuum pump. Set the flow rate between 60 and 100 cm 3/min
(0.13 and 0.21 ft 3/hr), and purge the train with stack gas for at
least 10 minutes.
8.2.3 When the temperatures at the exit ends of the probe and
filter are within the corresponding specified ranges, check the dry
ice level around the condensate trap, and add dry ice if necessary.
Record the clock time. To begin sampling, close the purge valve and
stop the pump. Open the sample valve and the sample tank valve.
Using the flow control valve, set the flow through the sample train
to the proper rate. Adjust the flow rate as necessary to maintain a
constant rate (±10 percent) throughout the duration of the sampling
period. Record the sample tank vacuum and flowmeter setting at
5-minute intervals. (See Figure 25-8.) Select a total sample time
greater than or equal to the minimum sampling time specified in the
applicable subpart of the regulations; end the sampling when this
time period is reached or when a constant flow rate can no longer
be maintained because of reduced sample tank vacuum.
Note:
If sampling had to be stopped before obtaining the minimum
sampling time (specified in the applicable subpart) because a
constant flow rate could not be maintained, proceed as follows:
After closing the sample tank valve, remove the used sample tank
from the sampling train (without disconnecting other portions of
the sampling train). Take another evacuated and leak-checked sample
tank, measure and record the tank vacuum, and attach the new tank
to the sampling train. After the new tank is attached to the sample
train, proceed with the sampling until the required minimum
sampling time has been exceeded.
8.3 Sample Recovery. After sampling is completed, close the flow
control valve, and record the final tank vacuum; then record the
tank temperature and barometric pressure. Close the sample tank
valve, and disconnect the sample tank from the sample system.
Disconnect the condensate trap at the inlet to the rate meter, and
tightly seal both ends of the condensate trap. Do not include the
probe from the stack to the filter as part of the condensate
sample.
8.4 Sample Storage and Transport. Keep the trap packed in dry
ice until the samples are returned to the laboratory for analysis.
Ensure that run numbers are identified on the condensate trap and
the sample tank(s).
9.0 Quality Control
Section
Quality control measure
Effect
10.1.1
Initial performance check of
condensate recovery apparatus
Ensure acceptable condensate
recovery efficiency.
10.1.2, 10.2
NMO analyzer initial and daily
performance checks
Ensure precision of analytical
results.
10.0 Calibration and Standardization Note:
Maintain a record of performance of each item.
10.1 Initial Performance Checks.
10.1.1 Condensate Recovery Apparatus. Perform these tests before
the system is first placed in operation, after any shutdown of 6
months or more, and after any major modification of the system, or
at the frequency recommended by the manufacturer.
10.1.1.1 Carrier Gas and Auxiliary O2 Blank Check. Analyze each
new tank of carrier gas or auxiliary O2 with the NMO analyzer to
check for contamination. Treat the gas cylinders as noncondensible
gas samples, and analyze according to the procedure in section
11.2.3. Add together any measured CH4, CO, CO2, or NMO. The total
concentration must be less than 5 ppm.
10.1.1.2 Oxidation Catalyst Efficiency Check.
10.1.1.2.1 With a clean condensate trap installed in the
recovery system or a 1/8″ stainless steel connector tube, replace
the carrier gas cylinder with the high level methane standard gas
cylinder (Section 7.4.1). Set the four-port valve to the recovery
position, and attach an ICV to the recovery system. With the sample
recovery valve in vent position and the flow-control and ICV valves
fully open, evacuate the manometer or gauge, the connecting tubing,
and the ICV to 10 mm Hg absolute pressure. Close the flow-control
and vacuum pump valves.
10.1.1.2.2 After the NDIR response has stabilized, switch the
sample recovery valve from vent to collect. When the manometer or
pressure gauge begins to register a slight positive pressure, open
the flow-control valve. Keep the flow adjusted such that the
pressure in the system is maintained within 10 percent of
atmospheric pressure. Continue collecting the sample in a normal
manner until the ICV is filled to a nominal gauge pressure of 300
mm Hg. Close the ICV valve, and remove the ICV from the system.
Place the sample recovery valve in the vent position, and return
the recovery system to its normal carrier gas and normal operating
conditions. Analyze the ICV for CO2 using the NMO analyzer; the
catalyst efficiency is acceptable if the CO2 concentration is
within 2 percent of the methane standard concentration.
10.1.1.3 System Performance Check. Construct a liquid sample
injection unit similar in design to the unit shown in Figure 25-7.
Insert this unit into the condensate recovery and conditioning
system in place of a condensate trap, and set the carrier gas and
auxiliary O2 flow rates to normal operating levels. Attach an
evacuated ICV to the system, and switch from system vent to
collect. With the carrier gas routed through the injection unit and
the oxidation catalyst, inject a liquid sample (see sections
10.1.1.3.1 to 10.1.1.3.4) into the injection port. Operate the trap
recovery system as described in section 11.1.3. Measure the final
ICV pressure, and then analyze the vessel to determine the CO2
concentration. For each injection, calculate the percent recovery
according to section 12.7. Calculate the relative standard
deviation for each set of triplicate injections according to
section 12.8. The performance test is acceptable if the average
percent recovery is 100 ±5 percent and the relative standard
deviation is less than 2 percent for each set of triplicate
injections.
10.1.1.3.1 50 µl hexane.
10.1.1.3.2 10 µl hexane.
10.1.1.3.3 50 µl decane.
10.1.1.3.4 10 µl decane.
10.1.2 NMO Analyzer. Perform these tests before the system is
first placed in operation, after any shutdown longer than 6 months,
and after any major modification of the system.
10.1.2.1 Oxidation Catalyst Efficiency Check. Turn off or bypass
the NMO analyzer reduction catalyst. Make triplicate injections of
the high level methane standard (Section 7.4.1). The oxidation
catalyst operation is acceptable if the FID response is less than 1
percent of the injected methane concentration.
10.1.2.2 Reduction Catalyst Efficiency Check. With the oxidation
catalyst unheated or bypassed and the heated reduction catalyst
bypassed, make triplicate injections of the high level methane
standard (Section 7.4.1). Repeat this procedure with both catalysts
operative. The reduction catalyst operation is acceptable if the
responses under both conditions agree within 5 percent of their
average.
10.1.2.3 NMO Analyzer Linearity Check Calibration. While
operating both the oxidation and reduction catalysts, conduct a
linearity check of the analyzer using the propane standards
specified in section 7.4.2. Make triplicate injections of each
calibration gas. For each gas (i.e., each set of triplicate
injections), calculate the average response factor (area/ppm C) for
each gas, as well as and the relative standard deviation (according
to section 12.8). Then calculate the overall mean of the response
factor values. The instrument linearity is acceptable if the
average response factor of each calibration gas is within 2.5
percent of the overall mean value and if the relative standard
deviation gas is less than 2 percent of the overall mean value.
Record the overall mean of the propane response factor values as
the NMO calibration response factor (RFNMO). Repeat the linearity
check using the CO2 standards specified in section 7.4.3. Make
triplicate injections of each gas, and then calculate the average
response factor (area/ppm C) for each gas, as well as the overall
mean of the response factor values. Record the overall mean of the
response factor values as the CO2 calibration response factor
(RFCO2). The RFCO2 must be within 10 percent of the RFNMO.
10.1.2.4 System Performance Check. Check the column separation
and overall performance of the analyzer by making triplicate
injections of the calibration gases listed in section 7.4.4. The
analyzer performance is acceptable if the measured NMO value for
each gas (average of triplicate injections) is within 5 percent of
the expected value.
10.2 NMO Analyzer Daily Calibration. The following calibration
procedures shall be performed before and immediately after the
analysis of each set of samples, or on a daily basis, whichever is
more stringent:
10.2.1 CO2 Response Factor. Inject triplicate samples of the
high level CO2 calibration gas (Section 7.4.3), and calculate the
average response factor. The system operation is adequate if the
calculated response factor is within 5 percent of the RFCO2
calculated during the initial performance test (Section 10.1.2.3).
Use the daily response factor (DRFCO2) for analyzer calibration and
the calculation of measured CO2 concentrations in the ICV
samples.
10.2.2 NMO Response Factors. Inject triplicate samples of the
mixed propane calibration cylinder gas (Section 7.4.4.1), and
calculate the average NMO response factor. The system operation is
adequate if the calculated response factor is within 10 percent of
the RFNMO calculated during the initial performance test (Section
10.1.2.4). Use the daily response factor (DRFNMO) for analyzer
calibration and calculation of NMO concentrations in the sample
tanks.
10.3 Sample Tank and ICV Volume. The volume of the gas sampling
tanks used must be determined. Determine the tank and ICV volumes
by weighing them empty and then filled with deionized distilled
water; weigh to the nearest 5 g, and record the results.
Alternatively, measure the volume of water used to fill them to the
nearest 5 ml.
11.0 Analytical Procedure
11.1 Condensate Recovery. See Figure 25-9. Set the carrier gas
flow rate, and heat the catalyst to its operating temperature to
condition the apparatus.
11.1.1 Daily Performance Checks. Each day before analyzing any
samples, perform the following tests:
11.1.1.1 Leak-Check. With the carrier gas inlets and the sample
recovery valve closed, install a clean condensate trap in the
system, and evacuate the system to 10 mm Hg absolute pressure or
less. Monitor the system pressure for 10 minutes. The system is
acceptable if the pressure change is less than 2 mm Hg.
11.1.1.2 System Background Test. Adjust the carrier gas and
auxiliary oxygen flow rate to their normal values of 100 cc/min and
150 cc/min, respectively, with the sample recovery valve in vent
position. Using a 10-ml syringe, withdraw a sample from the system
effluent through the syringe port. Inject this sample into the NMO
analyzer, and measure the CO2 content. The system background is
acceptable if the CO2 concentration is less than 10 ppm.
11.1.1.3 Oxidation Catalyst Efficiency Check. Conduct a catalyst
efficiency test as specified in section 10.1.1.2. If the criterion
of this test cannot be met, make the necessary repairs to the
system before proceeding.
11.1.2 Condensate Trap CO2 Purge and Sample Tank
Pressurization.
11.1.2.1 After sampling is completed, the condensate trap will
contain condensed water and organics and a small volume of sampled
gas. This gas from the stack may contain a significant amount of
CO2 which must be removed from the condensate trap before the
sample is recovered. This is accomplished by purging the condensate
trap with zero air and collecting the purged gas in the original
sample tank.
11.1.2.2 Begin with the sample tank and condensate trap from the
test run to be analyzed. Set the four-port valve of the condensate
recovery system in the CO2 purge position as shown in Figure 25-9.
With the sample tank valve closed, attach the sample tank to the
sample recovery system. With the sample recovery valve in the vent
position and the flow control valve fully open, evacuate the
manometer or pressure gauge to the vacuum of the sample tank. Next,
close the vacuum pump valve, open the sample tank valve, and record
the tank pressure.
11.1.2.3 Attach the dry ice-cooled condensate trap to the
recovery system, and initiate the purge by switching the sample
recovery valve from vent to collect position. Adjust the flow
control valve to maintain atmospheric pressure in the recovery
system. Continue the purge until the CO2 concentration of the trap
effluent is less than 5 ppm. CO2 concentration in the trap effluent
should be measured by extracting syringe samples from the recovery
system and analyzing the samples with the NMO analyzer. This
procedure should be used only after the NDIR response has reached a
minimum level. Using a 10-ml syringe, extract a sample from the
syringe port prior to the NDIR, and inject this sample into the NMO
analyzer.
11.1.2.4 After the completion of the CO2 purge, use the carrier
gas bypass valve to pressurize the sample tank to approximately
1,060 mm Hg absolute pressure with zero air.
11.1.3 Recovery of the Condensate Trap Sample (See Figure
25-10).
11.1.3.1 Attach the ICV to the sample recovery system. With the
sample recovery valve in a closed position, between vent and
collect, and the flow control and ICV valves fully open, evacuate
the manometer or gauge, the connecting tubing, and the ICV to 10 mm
Hg absolute pressure. Close the flow-control and vacuum pump
valves.
11.1.3.2 Begin auxiliary oxygen flow to the oxidation catalyst
at a rate of 150 cc/min, then switch the four-way valve to the trap
recovery position and the sample recovery valve to collect
position. The system should now be set up to operate as indicated
in Figure 25-10. After the manometer or pressure gauge begins to
register a slight positive pressure, open the flow control valve.
Adjust the flow-control valve to maintain atmospheric pressure in
the system within 10 percent.
11.1.3.3 Remove the condensate trap from the dry ice, and allow
it to warm to ambient temperature while monitoring the NDIR
response. If, after 5 minutes, the CO2 concentration of the
catalyst effluent is below 10,000 ppm, discontinue the auxiliary
oxygen flow to the oxidation catalyst. Begin heating the trap by
placing it in a furnace preheated to 200 °C (390 °F). Once heating
has begun, carefully monitor the NDIR response to ensure that the
catalyst effluent concentration does not exceed 50,000 ppm.
Whenever the CO2 concentration exceeds 50,000 ppm, supply auxiliary
oxygen to the catalyst at the rate of 150 cc/min. Begin heating the
tubing that connected the heated sample box to the condensate trap
only after the CO2 concentration falls below 10,000 ppm. This
tubing may be heated in the same oven as the condensate trap or
with an auxiliary heat source such as a heat gun. Heating
temperature must not exceed 200 °C (390 °F). If a heat gun is used,
heat the tubing slowly along its entire length from the upstream
end to the downstream end, and repeat the pattern for a total of
three times. Continue the recovery until the CO2 concentration
drops to less than 10 ppm as determined by syringe injection as
described under the condensate trap CO2 purge procedure (Section
11.1.2).
11.1.3.4 After the sample recovery is completed, use the carrier
gas bypass valve to pressurize the ICV to approximately 1060 mm Hg
absolute pressure with zero air.
11.2 Analysis. Once the initial performance test of the NMO
analyzer has been successfully completed (see section 10.1.2) and
the daily CO2 and NMO response factors have been determined (see
section 10.2), proceed with sample analysis as follows:
11.2.1 Operating Conditions. The carrier gas flow rate is 29.5
cc/min He and 2.2 cc/min O2. The column oven is heated to 85 °C
(185 °F). The order of elution for the sample from the column is
CO, CH4, CO2, and NMO.
11.2.2 Analysis of Recovered Condensate Sample. Purge the sample
loop with sample, and then inject the sample. Under the specified
operating conditions, the CO2 in the sample will elute in
approximately 100 seconds. As soon as the detector response returns
to baseline following the CO2 peak, switch the carrier gas flow to
backflush, and raise the column oven temperature to 195 °C (380 °F)
as rapidly as possible. A rate of 30 °C/min (90 °F) has been shown
to be adequate. Record the value obtained for the condensible
organic material (Ccm) measured as CO2 and any measured NMO. Return
the column oven temperature to 85 °C (185 °F) in preparation for
the next analysis. Analyze each sample in triplicate, and report
the average Ccm.
11.2.3 Analysis of Sample Tank. Perform the analysis as
described in section 11.2.2, but record only the value measured for
NMO (Ctm).
12.0 Data Analysis and Calculations
Carry out the calculations, retaining at least one extra
significant figure beyond that of the acquired data. Round off
figures after final calculations. All equations are written using
absolute pressure; absolute pressures are determined by adding the
measured barometric pressure to the measured gauge or manometer
pressure.
12.1 Nomenclature.
C = TGNMO concentration of the effluent, ppm C equivalent. Cc =
Calculated condensible organic (condensate trap) concentration of
the effluent, ppm C equivalent. Ccm = Measured concentration (NMO
analyzer) for the condensate trap ICV, ppm CO2. Ct = Calculated
noncondensible organic concentration (sample tank) of the effluent,
ppm C equivalent. Ctm = Measured concentration (NMO analyzer) for
the sample tank, ppm NMO. F = Sampling flow rate, cc/min. L =
Volume of liquid injected, µl. M = Molecular weight of the liquid
injected, g/g-mole. Mc = TGNMO mass concentration of the effluent,
mg C/dsm 3. N = Carbon number of the liquid compound injected (N =
12 for decane, N = 6 for hexane). n = Number of data points. Pf =
Final pressure of the intermediate collection vessel, mm Hg
absolute. Pb = Barometric pressure, cm Hg. Pti = Gas sample tank
pressure before sampling, mm Hg absolute. Pt = Gas sample tank
pressure after sampling, but before pressurizing, mm Hg absolute.
Ptf = Final gas sample tank pressure after pressurizing, mm Hg
absolute. q = Total number of analyzer injections of intermediate
collection vessel during analysis (where k = injection number, 1 *
* * q). r = Total number of analyzer injections of sample tank
during analysis (where j = injection number, 1 * * * r). r =
Density of liquid injected, g/cc. Tf = Final temperature of
intermediate collection vessel, °K. Tti = Sample tank temperature
before sampling, °K. Tt = Sample tank temperature at completion of
sampling, °K. Ttf = Sample tank temperature after pressurizing, °K.
V = Sample tank volume, m 3. Vt = Sample train volume, cc. Vv =
Intermediate collection vessel volume, m 3. Vs = Gas volume
sampled, dsm 3. xi = Individual measurements. x = Mean value. ΔP =
Allowable pressure change, cm Hg. Θ = Leak-check period, min.
12.2 Allowable Pressure Change. For the pretest leak-check,
calculate the allowable pressure change using Equation 25-1:
12.3 Sample Volume. For each test run, calculate the gas volume
sampled using Equation 25-2:
12.4 Noncondensible Organics. For each sample tank, determine
the concentration of nonmethane organics (ppm C) using Equation
25-3:
12.5 Condensible Organics. For each condensate trap determine
the concentration of organics (ppm C) using Equation 25-4:
12.6 TGNMO Mass Concentration. Determine the TGNMO mass
concentration as carbon for each test run, using Equation 25-5:
12.7 Percent Recovery. Calculate the percent recovery for the
liquid injections to the condensate recovery and conditioning
system using Equation 25-6:
where K = 1.604 (°K)(g-mole)(%)/(mm Hg)(ml)(m
3)(ppm).
12.8 Relative Standard Deviation. Use Equation 25-7 to calculate
the relative standard deviation (RSD) of percent recovery and
analyzer linearity.
13.0 Method Performance
13.1 Range. The minimum detectable limit of the method has been
determined to be 50 parts per million by volume (ppm). No upper
limit has been established.
1. Salo, A.E., S. Witz, and R.D. MacPhee. Determination of
Solvent Vapor Concentrations by Total Combustion Analysis: A
Comparison of Infrared with Flame Ionization Detectors. Paper No.
75-33.2. (Presented at the 68th Annual Meeting of the Air Pollution
Control Association. Boston, MA. June 15-20, 1975.) 14 p.
2. Salo, A.E., W.L. Oaks, and R.D. MacPhee. Measuring the
Organic Carbon Content of Source Emissions for Air Pollution
Control. Paper No. 74-190. (Presented at the 67th Annual Meeting of
the Air Pollution Control Association. Denver, CO. June 9-13,
1974.) 25 p.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 25A -
Determination of Total Gaseous Organic Concentration Using a Flame
Ionization Analyzer 1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Total Organic
Compounds
N/A
<2% of span.
1.2 Applicability. This method is applicable for the
determination of total gaseous organic concentration of vapors
consisting primarily of alkanes, alkenes, and/or arenes (aromatic
hydrocarbons). The concentration is expressed in terms of propane
(or other appropriate organic calibration gas) or in terms of
carbon.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A gas sample is extracted from the source through a heated
sample line and glass fiber filter to a flame ionization analyzer
(FIA). Results are reported as volume concentration equivalents of
the calibration gas or as carbon equivalents.
3.0 Definitions
3.1 Calibration drift means the difference in the
measurement system response to a mid-level calibration gas before
and after a stated period of operation during which no unscheduled
maintenance, repair, or adjustment took place.
3.2 Calibration error means the difference between the
gas concentration indicated by the measurement system and the know
concentration of the calibration gas.
3.3 Calibration gas means a known concentration of a gas
in an appropriate diluent gas.
3.4 Measurement system means the total equipment required
for the determination of the gas concentration. The system consists
of the following major subsystems:
3.4.1 Sample interface means that portion of a system
used for one or more of the following: sample acquisition, sample
transportation, sample conditioning, or protection of the
analyzer(s) from the effects of the stack effluent.
3.4.2 Organic analyzer means that portion of the
measurement system that senses the gas to be measured and generates
an output proportional to its concentration.
3.5 Response time means the time interval from a step
change in pollutant concentration at the inlet to the emission
measurement system to the time at which 95 percent of the
corresponding final value is reached as displayed on the
recorder.
3.6 Span Value means the upper limit of a gas
concentration measurement range that is specified for affected
source categories in the applicable part of the regulations. The
span value is established in the applicable regulation and is
usually 1.5 to 2.5 times the applicable emission limit. If no span
value is provided, use a span value equivalent to 1.5 to 2.5 times
the expected concentration. For convenience, the span value should
correspond to 100 percent of the recorder scale.
3.7 Zero drift means the difference in the measurement
system response to a zero level calibration gas before or after a
stated period of operation during which no unscheduled maintenance,
repair, or adjustment took place.
4.0 Interferences [Reserved] 5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method. The analyzer users manual should be consulted for
specific precautions to be taken with regard to the analytical
procedure.
5.2 Explosive Atmosphere. This method is often applied in highly
explosive areas. Caution and care should be exercised in choice of
equipment and installation.
6.0 Equipment and Supplies
6.1 Measurement System. Any measurement system for total organic
concentration that meets the specifications of this method. A
schematic of an acceptable measurement system is shown in Figure
25A-1. All sampling components leading to the analyzer shall be
heated ≥110 °C (220 °F) throughout the sampling period, unless
safety reasons are cited (Section 5.2) The essential components of
the measurement system are described below:
6.1.1 Organic Concentration Analyzer. A flame ionization
analyzer (FIA) capable of meeting or exceeding the specifications
of this method. The flame ionization detector block shall be heated
>120 °C (250 °F).
6.1.2 Sample Probe. Stainless steel, or equivalent, three-hole
rake type. Sample holes shall be 4 mm (0.16-in.) in diameter or
smaller and located at 16.7, 50, and 83.3 percent of the equivalent
stack diameter. Alternatively, a single opening probe may be used
so that a gas sample is collected from the centrally located 10
percent area of the stack cross-section.
6.1.3 Heated Sample Line. Stainless steel or Teflon” tubing to
transport the sample gas to the analyzer. The sample line should be
heated (≥110 °C) to prevent any condensation.
6.1.4 Calibration Valve Assembly. A three-way valve assembly to
direct the zero and calibration gases to the analyzers is
recommended. Other methods, such as quick-connect lines, to route
calibration gas to the analyzers are applicable.
6.1.5 Particulate Filter. An in-stack or an out-of-stack glass
fiber filter is recommended if exhaust gas particulate loading is
significant. An out-of-stack filter should be heated to prevent any
condensation.
6.1.6 Recorder. A strip-chart recorder, analog computer, or
digital recorder for recording measurement data. The minimum data
recording requirement is one measurement value per minute.
7.0 Reagents and Standards
7.1 Calibration Gases. The calibration gases for the gas
analyzer shall be propane in air or propane in nitrogen.
Alternatively, organic compounds other than propane can be used;
the appropriate corrections for response factor must be made.
Calibration gases shall be prepared in accordance with the
procedure listed in Citation 2 of section 16. Additionally, the
manufacturer of the cylinder should provide a recommended shelf
life for each calibration gas cylinder over which the concentration
does not change more than ±2 percent from the certified value. For
calibration gas values not generally available (i.e.,
organics between 1 and 10 percent by volume), alternative methods
for preparing calibration gas mixtures, such as dilution systems
(Test Method 205, 40 CFR Part 51, Appendix M), may be used with
prior approval of the Administrator.
7.1.1 Fuel. A 40 percent H2/60 percent N2 gas mixture is
recommended to avoid an oxygen synergism effect that reportedly
occurs when oxygen concentration varies significantly from a mean
value.
7.1.2 Zero Gas. High purity air with less than 0.1 part per
million by volume (ppmv) of organic material (propane or carbon
equivalent) or less than 0.1 percent of the span value, whichever
is greater.
7.1.3 Low-level Calibration Gas. An organic calibration gas with
a concentration equivalent to 25 to 35 percent of the applicable
span value.
7.1.4 Mid-level Calibration Gas. An organic calibration gas with
a concentration equivalent to 45 to 55 percent of the applicable
span value.
7.1.5 High-level Calibration Gas. An organic calibration gas
with a concentration equivalent to 80 to 90 percent of the
applicable span value.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Selection of Sampling Site. The location of the sampling
site is generally specified by the applicable regulation or purpose
of the test (i.e., exhaust stack, inlet line, etc.). The
sample port shall be located to meet the testing requirements of
Method 1.
8.2 Location of Sample Probe. Install the sample probe so that
the probe is centrally located in the stack, pipe, or duct and is
sealed tightly at the stack port connection.
8.3 Measurement System Preparation. Prior to the emission test,
assemble the measurement system by following the manufacturer's
written instructions for preparing sample interface and the organic
analyzer. Make the system operable (Section 10.1).
8.4 Calibration Error Test. Immediately prior to the test series
(within 2 hours of the start of the test), introduce zero gas and
high-level calibration gas at the calibration valve assembly.
Adjust the analyzer output to the appropriate levels, if necessary.
Calculate the predicted response for the low-level and mid-level
gases based on a linear response line between the zero and
high-level response. Then introduce low-level and mid-level
calibration gases successively to the measurement system. Record
the analyzer responses for low-level and mid-level calibration
gases and determine the differences between the measurement system
responses and the predicted responses. These differences must be
less than 5 percent of the respective calibration gas value. If
not, the measurement system is not acceptable and must be replaced
or repaired prior to testing. No adjustments to the measurement
system shall be conducted after the calibration and before the
drift check (Section 8.6.2). If adjustments are necessary before
the completion of the test series, perform the drift checks prior
to the required adjustments and repeat the calibration following
the adjustments. If multiple electronic ranges are to be used, each
additional range must be checked with a mid-level calibration gas
to verify the multiplication factor.
8.5 Response Time Test. Introduce zero gas into the measurement
system at the calibration valve assembly. When the system output
has stabilized, switch quickly to the high-level calibration gas.
Record the time from the concentration change to the measurement
system response equivalent to 95 percent of the step change. Repeat
the test three times and average the results.
8.6 Emission Measurement Test Procedure.
8.6.1 Organic Measurement. Begin sampling at the start of the
test period, recording time and any required process information as
appropriate. In particulate, note on the recording chart, periods
of process interruption or cyclic operation.
8.6.2 Drift Determination. Immediately following the completion
of the test period and hourly during the test period, reintroduce
the zero and mid-level calibration gases, one at a time, to the
measurement system at the calibration valve assembly. (Make no
adjustments to the measurement system until both the zero and
calibration drift checks are made.) Record the analyzer response.
If the drift values exceed the specified limits, invalidate the
test results preceding the check and repeat the test following
corrections to the measurement system. Alternatively, recalibrate
the test measurement system as in section 8.4 and report the
results using both sets of calibration data (i.e., data determined
prior to the test period and data determined following the test
period).
Note:
Note on the recording chart periods of process interruption or
cyclic operation.
9.0 Quality Control
Method section
Quality control measure
Effect
8.4
Zero and calibration drift
tests
Ensures that bias introduced
by drift in the measurement system output during the run is no
greater than 3 percent of span.
10.0 Calibration and Standardization
10.1 FIA equipment can be calibrated for almost any range of
total organic concentrations. For high concentrations of organics
(>1.0 percent by volume as propane), modifications to most
commonly available analyzers are necessary. One accepted method of
equipment modification is to decrease the size of the sample to the
analyzer through the use of a smaller diameter sample capillary.
Direct and continuous measurement of organic concentration is a
necessary consideration when determining any modification
design.
11.0 Analytical Procedure
The sample collection and analysis are concurrent for this
method (see section 8.0).
12.0 Calculations and Data Analysis
12.1 Determine the average organic concentration in terms of
ppmv as propane or other calibration gas. The average shall be
determined by integration of the output recording over the period
specified in the applicable regulation. If results are required in
terms of ppmv as carbon, adjust measured concentrations using
Equation 25A-1.
Where: Cc = Organic concentration as carbon,
ppmv. Cmeas = Organic concentration as measured, ppmv. K = Carbon
equivalent correction factor. = 2 for ethane. = 3 for propane. = 4
for butane. = Appropriate response factor for other organic
calibration gases. 13.0 Method Performance
13.1 Measurement System Performance Specifications.
13.1.1 Zero Drift. Less than ±3 percent of the span value.
13.1.2 Calibration Drift. Less than ±3 percent of span
value.
13.1.3 Calibration Error. Less than ±5 percent of the
calibration gas value.
1. Measurement of Volatile Organic Compounds - Guideline Series.
U.S. Environmental Protection Agency. Research Triangle Park, NC.
Publication No. EPA-450/2-78-041. June 1978. p. 46-54.
2. EPA Traceability Protocol for Assay and Certification of
Gaseous Calibration Standards. U.S. Environmental Protection
Agency, Quality Assurance and Technical Support Division. Research
Triangle Park, N.C. September 1993.
3. Gasoline Vapor Emission Laboratory Evaluation - Part 2. U.S.
Environmental Protection Agency, Office of Air Quality Planning and
Standards. Research Triangle Park, NC. EMB Report No. 75-GAS-6.
August 1975.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 25B -
Determination of Total Gaseous Organic Concentration Using a
Nondispersive Infrared Analyzer Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling) essential to its performance. Some material is
incorporated by reference from other methods in this part.
Therefore, to obtain reliable results, persons using this method
should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 6C, and Method 25A.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Sensitivity
Total Organic
Compounds
N/A
<2% of span.
1.2 Applicability. This method is applicable for the
determination of total gaseous organic concentration of vapors
consisting primarily of alkanes. Other organic materials may be
measured using the general procedure in this method, the
appropriate calibration gas, and an analyzer set to the appropriate
absorption band.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
A gas sample is extracted from the source through a heated
sample line, if necessary, and glass fiber filter to a
nondispersive infrared analyzer (NDIR). Results are reported as
volume concentration equivalents of the calibration gas or as
carbon equivalents.
3.0 Definitions
Same as Method 25A, section 3.0.
4.0 Interferences [Reserved] 5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and determine the
applicability of regulatory limitations prior to performing this
test method. The analyzer users manual should be consulted for
specific precautions to be taken with regard to the analytical
procedure.
5.2 Explosive Atmosphere. This method is often applied in highly
explosive areas. Caution and care should be exercised in choice of
equipment and installation.
6.0 Equipment and Supplies
Same as Method 25A, section 6.0, with the exception of the
following:
6.1 Organic Concentration Analyzer. A nondispersive infrared
analyzer designed to measure alkane organics and capable of meeting
or exceeding the specifications in this method.
7.0 Reagents and Standards
Same as Method 25A, section 7.1. No fuel gas is required for an
NDIR.
8.0 Sample Collection, Preservation, Storage, and Transport
Same as Method 25A, section 8.0.
9.0 Quality Control
Same as Method 25A, section 9.0.
10.0 Calibration and Standardization
Same as Method 25A, section 10.0.
11.0 Analytical Procedure
The sample collection and analysis are concurrent for this
method (see section 8.0).
17.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
Method 25C - Determination of Nonmethane Organic Compounds (NMOC)
in Landfill Gases Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should also have a thorough knowledge of EPA Method 25.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Nonmethane organic
compounds (NMOC)
No CAS number assigned.
1.2 Applicability. This method is applicable to the sampling and
measurement of NMOC as carbon in landfill gases (LFG).
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A sample probe that has been perforated at one end is driven
or augured to a depth of 0.9 m (3 ft) below the bottom of the
landfill cover. A sample of the landfill gas is extracted with an
evacuated cylinder. The NMOC content of the gas is determined by
injecting a portion of the gas into a gas chromatographic column to
separate the NMOC from carbon monoxide (CO), carbon dioxide (CO2),
and methane (CH4); the NMOC are oxidized to CO2, reduced to CH4,
and measured by a flame ionization detector (FID). In this manner,
the variable response of the FID associated with different types of
organics is eliminated.
5.1 Since this method is complex, only experienced personnel
should perform this test. LFG contains methane, therefore explosive
mixtures may exist on or near the landfill. It is advisable to take
appropriate safety precautions when testing landfills, such as
refraining from smoking and installing explosion-proof
equipment.
6.0 Equipment and Supplies
6.1 Sample Probe. Stainless steel, with the bottom third
perforated. Teflon probe liners and sampling lines are also
allowed. Non-perforated probes are allowed as long as they are
withdrawn to create a gap equivalent to having the bottom third
perforated. The sample probe must be capped at the bottom and must
have a threaded cap with a sampling attachment at the top. The
sample probe must be long enough to go through and extend no less
than 0.9 m (3 ft) below the landfill cover. If the sample probe is
to be driven into the landfill, the bottom cap should be designed
to facilitate driving the probe into the landfill.
6.2 Sampling Train.
6.2.1 Rotameter with Flow Control Valve. Capable of measuring a
sample flow rate of 100 ±10 ml/min. The control valve must be made
of stainless steel.
6.2.2 Sampling Valve. Stainless steel.
6.2.3 Pressure Gauge. U-tube mercury manometer, or equivalent,
capable of measuring pressure to within 1 mm Hg (0.5 in H2O) in the
range of 0 to 1,100 mm Hg (0 to 590 in H2O).
6.2.4 Sample Tank. Stainless steel or aluminum cylinder,
equipped with a stainless steel sample tank valve.
6.3 Vacuum Pump. Capable of evacuating to an absolute pressure
of 10 mm Hg (5.4 in H2O).
6.4 Purging Pump. Portable, explosion proof, and suitable for
sampling NMOC.
6.5 Pilot Probe Procedure. The following are needed only if the
tester chooses to use the procedure described in section 8.2.1.
6.5.1 Pilot Probe. Tubing of sufficient strength to withstand
being driven into the landfill by a post driver and an outside
diameter of at least 6 mm (0.25 in.) smaller than the sample probe.
The pilot probe shall be capped on both ends and long enough to go
through the landfill cover and extend no less than 0.9 m (3 ft)
into the landfill.
6.5.2 Post Driver and Compressor. Capable of driving the pilot
probe and the sampling probe into the landfill. The Kitty Hawk
portable post driver has been found to be acceptable.
6.6 Auger Procedure. The following are needed only if the tester
chooses to use the procedure described in section 8.2.2.
6.6.1 Auger. Capable of drilling through the landfill cover and
to a depth of no less than 0.9 m (3 ft) into the landfill.
6.6.2 Pea Gravel.
6.6.3 Bentonite.
6.7 NMOC Analyzer, Barometer, Thermometer, and Syringes. Same as
in sections 6.3.1, 6.3.2, 6.33, and 6.2.10, respectively, of Method
25.
7.0 Reagents and Standards
7.1 NMOC Analysis. Same as in Method 25, section 7.2.
7.2 Calibration. Same as in Method 25, section 7.4, except omit
section 7.4.3.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Sample Tank Evacuation and Leak-Check. Conduct the sample
tank evacuation and leak-check either in the laboratory or the
field. Connect the pressure gauge and sampling valve to the sample
tank. Evacuate the sample tank to 10 mm Hg (5.4 in H2O) absolute
pressure or less. Close the sampling valve, and allow the tank to
sit for 30 minutes. The tank is acceptable if no change more than
±2 mm is noted. Include the results of the leak-check in the test
report.
8.2 Sample Probe Installation. The tester may use the procedure
in section 8.2.1 or 8.2.2.
8.2.1 Pilot Probe Procedure. Use the post driver to drive the
pilot probe at least 0.9 m (3 ft) below the landfill cover.
Alternative procedures to drive the probe into the landfill may be
used subject to the approval of the Administrator's designated
representative.
8.2.1.1 Remove the pilot probe and drive the sample probe into
the hole left by the pilot probe. The sample probe shall extend at
least 0.9 m (3 ft) below the landfill cover and shall protrude
about 0.3 m (1 ft) above the landfill cover. Seal around the
sampling probe with bentonite and cap the sampling probe with the
sampling probe cap.
8.2.2 Auger Procedure. Use an auger to drill a hole to at least
0.9 m (3 ft) below the landfill cover. Place the sample probe in
the hole and backfill with pea gravel to a level 0.6 m (2 ft) from
the surface. The sample probe shall protrude at least 0.3 m (1 ft)
above the landfill cover. Seal the remaining area around the probe
with bentonite. Allow 24 hours for the landfill gases to
equilibrate inside the augured probe before sampling.
8.2.3 Driven Probes. Closed-point probes may be driven directly
into the landfill in a single step. This method may not require
backfilling if the probe is adequately sealed by its insertion.
Unperforated probes that are inserted in this manner and withdrawn
at a distance from a detachable tip to create an open space are
also acceptable.
8.3 Sample Train Assembly. Just before assembling the sample
train, measure the sample tank vacuum using the pressure gauge.
Record the vacuum, the ambient temperature, and the barometric
pressure at this time. Assemble the sampling probe purging system
as shown in Figure 25C-1.
8.4 Sampling Procedure. Open the sampling valve and use the
purge pump and the flow control valve to evacuate at least two
sample probe volumes from the system at a flow rate of 500 ml/min
or less. Close the sampling valve and replace the purge pump with
the sample tank apparatus as shown in Figure 25C-2. Open the
sampling valve and the sample tank valve and, using the flow
control valve, sample at a flow rate of 500 ml/min or less until
either a constant flow rate can no longer be maintained because of
reduced sample tank vacuum or the appropriate composite volume is
attained. Disconnect the sampling tank apparatus and pressurize the
sample cylinder to approximately 1,060 mm Hg (567 in. H2O) absolute
pressure with helium, and record the final pressure. Alternatively,
the sample tank may be pressurized in the lab.
8.4.1 The following restrictions apply to compositing samples
from different probe sites into a single cylinder: (1) Individual
composite samples per cylinder must be of equal volume; this must
be verified by recording the flow rate, sampling time, vacuum
readings, or other appropriate volume measuring data, (2)
individual composite samples must have a minimum volume of 1 liter
unless data is provided showing smaller volumes can be accurately
measured, and (3) composite samples must not be collected using the
final cylinder vacuum as it diminishes to ambient pressure.
8.4.2 Use Method 3C to determine the percent N2 and O2 in each
cylinder. The presence of N2 and O2 indicate either infiltration of
ambient air into the landfill gas sample or an inappropriate
testing site has been chosen where anaerobic decomposition has not
begun. The landfill gas sample is acceptable if the concentration
of N2 is less than 20 percent. Alternatively, the oxygen content of
each cylinder must be less than 5 percent. Landfills with 3-year
average annual rainfalls equal to or less than 20 inches annual
rainfalls samples are acceptable when the N2 to O2 concentration
ratio is greater than 3.71.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
8.4.2
If the 3-year average annual
rainfall is greater than 20 inches, verify that landfill gas sample
contains less than 20 percent N2 and 5 percent O2. Landfills with
3-year average annual rainfalls equal to or less than 20 inches
annual rainfalls samples are acceptable when the N2 to O2
concentration ratio is greater than 3.71
Ensures that ambient air was
not drawn into the landfill gas sample and gas was sampled from an
appropriate location. If outside of range, invalidate sample and
repeat sample collection.
10.1, 10.2
NMOC analyzer initial and
daily performance checks
Ensures precision of
analytical results.
10.0 Calibration and Standardization Note:
Maintain a record of performance of each item.
10.1 Initial NMOC Analyzer Performance Test. Same as in Method
25, section 10.1, except omit the linearity checks for CO2
standards.
10.2 NMOC Analyzer Daily Calibration.
10.2.1 NMOC Response Factors. Same as in Method 25, section
10.2.2.
10.3 Sample Tank Volume. The volume of the gas sampling tanks
must be determined. Determine the tank volumes by weighing them
empty and then filled with deionized water; weigh to the nearest 5
g, and record the results. Alternatively, measure the volume of
water used to fill them to the nearest 5 ml.
11.0 Analytical Procedures
11.1 The oxidation, reduction, and measurement of NMOC's is
similar to Method 25. Before putting the NMOC analyzer into routine
operation, conduct an initial performance test. Start the analyzer,
and perform all the necessary functions in order to put the
analyzer into proper working order. Conduct the performance test
according to the procedures established in section 10.1. Once the
performance test has been successfully completed and the NMOC
calibration response factor has been determined, proceed with
sample analysis as follows:
11.1.1 Daily Operations and Calibration Checks. Before and
immediately after the analysis of each set of samples or on a daily
basis (whichever occurs first), conduct a calibration test
according to the procedures established in section 10.2. If the
criteria of the daily calibration test cannot be met, repeat the
NMOC analyzer performance test (Section 10.1) before
proceeding.
11.1.2 Operating Conditions. Same as in Method 25, section
11.2.1.
11.1.3 Analysis of Sample Tank. Purge the sample loop with
sample, and then inject the sample. Under the specified operating
conditions, the CO2 in the sample will elute in approximately 100
seconds. As soon as the detector response returns to baseline
following the CO2 peak, switch the carrier gas flow to backflush,
and raise the column oven temperature to 195 °C (383 °F) as rapidly
as possible. A rate of 30 °C/min (54 °F/min) has been shown to be
adequate. Record the value obtained for any measured NMOC. Return
the column oven temperature to 85 °C (185 °F) in preparation for
the next analysis. Analyze each sample in triplicate, and report
the average as Ctm.
12.0 Data Analysis and Calculations Note:
All equations are written using absolute pressure; absolute
pressures are determined by adding the measured barometric pressure
to the measured gauge or manometer pressure.
12.1 Nomenclature
Bw = Moisture content in the sample, fraction. CN2 = N2
concentration in the diluted sample gas. CmN2 = Measured N2
concentration, fraction in landfill gas. CmOx = Measured Oxygen
concentration, fraction in landfill gas. COx = Oxygen concentration
in the diluted sample gas. Ct = Calculated NMOC concentration, ppmv
C equivalent. Ctm = Measured NMOC concentration, ppmv C equivalent.
Pb = Barometric pressure, mm Hg. Pt = Gas sample tank pressure
after sampling, but before pressurizing, mm Hg absolute. Ptf =
Final gas sample tank pressure after pressurizing, mm Hg absolute.
Pti = Gas sample tank pressure after evacuation, mm Hg absolute. Pw
= Vapor pressure of H2O (from Table 25C-1), mm Hg. r = Total number
of analyzer injections of sample tank during analysis (where j =
injection number, 1 . . . r). Tt = Sample tank temperature at
completion of sampling, °K. Tti = Sample tank temperature before
sampling, °K. Ttf = Sample tank temperature after pressuring, °K.
12.2 Water Correction. Use Table 25C-1 (Section 17.0), the LFG
temperature, and barometric pressure at the sampling site to
calculate Bw.
12.3 Nitrogen Concentration in the landfill gas. Use equation
25C-2 to calculate the measured concentration of nitrogen in the
original landfill gas.
12.4 Oxygen Concentration in the landfill gas. Use equation
25C-3 to calculate the measured concentration of oxygen in the
original landfill gas.
12.5 You must correct the NMOC Concentration for the
concentration of nitrogen or oxygen based on which gas or gases
passes the requirements in section 9.1 or based on the 3-year
average annual rainfall based on the closest NOAA land-based
station.
12.5.1 NMOC Concentration with nitrogen correction. Use Equation
25C-4 to calculate the concentration of NMOC for each sample tank
when the nitrogen concentration is less than 20 percent.
12.5.2 NMOC Concentration with oxygen correction. Use Equation
25C-5 to calculate the concentration of NMOC for each sample tank
if the landfill gas oxygen is less than 5 percent and the landfill
gas nitrogen concentration is greater than 20 percent, or 3-year
average annual rainfall based annual rainfall of less than 20
inches.
1. Salo, Albert E., Samuel Witz, and Robert D. MacPhee.
Determination of Solvent Vapor Concentrations by Total Combustion
Analysis: A Comparison of Infrared with Flame Ionization Detectors.
Paper No. 75-33.2. (Presented at the 68th Annual Meeting of the Air
Pollution Control Association. Boston, Massachusetts. June 15-20,
1975.) 14 p.
2. Salo, Albert E., William L. Oaks, and Robert D. MacPhee.
Measuring the Organic Carbon Content of Source Emissions for Air
Pollution Control. Paper No. 74-190. (Presented at the 67th Annual
Meeting of the Air Pollution Control Association. Denver, Colorado.
June 9-13, 1974.) 25 p.
17.0 Tables, Diagrams, Flowcharts, and Validation Data
Table 25C-1 - Moisture Correction
Temperature, °C
Vapor Pressure of H2O, mm
Hg
Temperature, °C
Vapor Pressure of H2O, mm
Hg
4
6.1
18
15.5
6
7.0
20
17.5
8
8.0
22
19.8
10
9.2
24
22.4
12
10.5
26
25.2
14
12.0
28
28.3
16
13.6
30
31.8
Method 25D - Determination of the Volatile Organic Concentration of
Waste Samples Note:
Performance of this method should not be attempted by persons
unfamiliar with the operation of a flame ionization detector (FID)
or an electrolytic conductivity detector (ELCD) because knowledge
beyond the scope of this presentation is required.
1.0 Scope and Application
1.1 Analyte. Volatile Organic Compounds. No CAS No.
assigned.
1.2 Applicability. This method is applicable for determining the
volatile organic (VO) concentration of a waste sample.
2.0 Summary of Method
2.1 Principle. A sample of waste is obtained at a point which is
most representative of the unexposed waste (where the waste has had
minimum opportunity to volatilize to the atmosphere). The sample is
suspended in an organic/aqueous matrix, then heated and purged with
nitrogen for 30 min. in order to separate certain organic
compounds. Part of the sample is analyzed for carbon concentration,
as methane, with an FID, and part of the sample is analyzed for
chlorine concentration, as chloride, with an ELCD. The VO
concentration is the sum of the carbon and chlorine content of the
sample.
3.0 Definitions
3.1 Well-mixed in the context of this method refers to
turbulent flow which results in multiple-phase waste in effect
behaving as single-phase waste due to good mixing.
4.0 Interferences [Reserved] 5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies Note:
Mention of trade names or specific products does not constitute
endorsement by the Environmental Protection Agency.
6.1 Sampling. The following equipment is required:
6.1.1 Sampling Tube. Flexible Teflon, 0.25 in. ID (6.35 mm).
6.1.2 Sample Container. Borosilicate glass, 40-mL, and a
Teflon-lined screw cap capable of forming an air tight seal.
6.1.3 Cooling Coil. Fabricated from 0.25 in (6.35 mm). ID 304
stainless steel tubing with a thermocouple at the coil outlet.
6.2 Analysis. The following equipment is required.
6.2.1 Purging Apparatus. For separating the VO from the waste
sample. A schematic of the system is shown in Figure 25D-1. The
purging apparatus consists of the following major components.
6.2.1.1 Purging Flask. A glass container to hold the sample
while it is heated and purged with dry nitrogen. The cap of the
purging flask is equipped with three fittings: one for a purging
lance (fitting with the #7 Ace-thread), one for the Teflon exit
tubing (side fitting, also a #7 Ace-thread), and a third (a 50-mm
Ace-thread) to attach the base of the purging flask as shown in
Figure 25D-2. The base of the purging flask is a 50-mm ID (2 in)
cylindrical glass tube. One end of the tube is open while the other
end is sealed. Exact dimensions are shown in Figure 25D-2.
6.2.1.2 Purging Lance. Glass tube, 6-mm OD (0.2 in) by 30 cm (12
in) long. The purging end of the tube is fitted with a four-arm
bubbler with each tip drawn to an opening 1 mm (0.04 in) in
diameter. Details and exact dimensions are shown in Figure
25D-2.
6.2.1.3 Coalescing Filter. Porous fritted disc incorporated into
a container with the same dimensions as the purging flask. The
details of the design are shown in Figure 25D-3.
6.2.1.4 Constant Temperature Chamber. A forced draft oven
capable of maintaining a uniform temperature around the purging
flask and coalescing filter of 75 ±2 °C (167 ±3.6 °F).
6.2.1.5 Three-way Valve. Manually operated, stainless steel. To
introduce calibration gas into system.
6.2.1.6 Flow Controllers. Two, adjustable. One capable of
maintaining a purge gas flow rate of 6 ±0.06 L/min (0.2 ±0.002 ft
3/min) The other capable of maintaining a calibration gas flow rate
of 1-100 mL/min (0.00004-0.004 ft 3/min).
6.2.1.7 Rotameter. For monitoring the air flow through the
purging system (0-10 L/min)(0-0.4 ft 3/min).
6.2.1.8 Sample Splitters. Two heated flow restrictors (placed
inside oven or heated to 120 ±10 °C (248 ±18 °F) ). At a purge rate
of 6 L/min (0.2 ft 3/min), one will supply a constant flow to the
first detector (the rest of the flow will be directed to the second
sample splitter). The second splitter will split the analytical
flow between the second detector and the flow restrictor. The
approximate flow to the FID will be 40 mL/min (0.0014 ft 3/min) and
to the ELCD will be 15 mL/min (0.0005 ft 3/min), but the exact flow
must be adjusted to be compatible with the individual detector and
to meet its linearity requirement. The two sample splitters will be
connected to each other by 1/8′ OD (3.175 mm) stainless steel
tubing.
6.2.1.9 Flow Restrictor. Stainless steel tubing, 1/8′ OD (3.175
mm), connecting the second sample splitter to the ice bath. Length
is determined by the resulting pressure in the purging flask (as
measured by the pressure gauge). The resulting pressure from the
use of the flow restrictor shall be 6-7 psig.
6.2.1.10 Filter Flask. With one-hole stopper. Used to hold ice
bath. Excess purge gas is vented through the flask to prevent
condensation in the flowmeter and to trap volatile organic
compounds.
6.2.1.11 Four-way Valve. Manually operated, stainless steel.
Placed inside oven, used to bypass purging flask.
6.2.1.12 On/Off Valves. Two, stainless steel. One heat resistant
up to 130 °C (266 °F) and placed between oven and ELCD. The other a
toggle valve used to control purge gas flow.
6.2.1.13 Pressure Gauge. Range 0-40 psi. To monitor pressure in
purging flask and coalescing filter.
6.2.1.14 Sample Lines. Teflon, 1/4′ OD (6.35 mm), used inside
the oven to carry purge gas to and from purging chamber and to and
from coalescing filter to four-way valve. Also used to carry sample
from four-way valve to first sample splitter.
6.2.1.15 Detector Tubing. Stainless steel, 1/8′ OD (3.175 mm),
heated to 120 ±10 °C (248 ±18 °F) . Used to carry sample gas from
each sample splitter to a detector. Each piece of tubing must be
wrapped with heat tape and insulating tape in order to insure that
no cold spots exist. The tubing leading to the ELCD will also
contain a heat-resistant on-off valve (Section 6.2.1.12) which
shall also be wrapped with heat-tape and insulation.
6.2.2 Volatile Organic Measurement System. Consisting of an FID
to measure the carbon concentration of the sample and an ELCD to
measure the chlorine concentration.
6.2.2.1 FID. A heated FID meeting the following specifications
is required.
6.2.2.1.1 Linearity. A linear response (±5 percent) over the
operating range as demonstrated by the procedures established in
section 10.1.1.
6.2.2.1.2 Range. A full scale range of 50 pg carbon/sec to 50 µg
carbon/sec. Signal attenuators shall be available to produce a
minimum signal response of 10 percent of full scale.
6.2.2.1.3 Data Recording System. A digital integration system
compatible with the FID for permanently recording the output of the
detector. The recorder shall have the capability to start and stop
integration at points selected by the operator or it shall be
capable of the “integration by slices” technique (this technique
involves breaking down the chromatogram into smaller increments,
integrating the area under the curve for each portion, subtracting
the background for each portion, and then adding all of the areas
together for the final area count).
6.2.2.2 ELCD. An ELCD meeting the following specifications is
required. 1-propanol must be used as the electrolyte. The
electrolyte flow through the conductivity cell shall be 1 to 2
mL/min (0.00004 to 0.00007 ft 3/min).
Note:
A 1/4-in. ID (6.35 mm) quartz reactor tube is strongly
recommended to reduce carbon buildup and the resulting detector
maintenance.
6.2.2.2.1 Linearity. A linear response (±10 percent) over the
response range as demonstrated by the procedures in section
10.1.2.
6.2.2.2.2 Range. A full scale range of 5.0 pg/sec to 500 ng/sec
chloride. Signal attenuators shall be available to produce a
minimum signal response of 10 percent of full scale.
6.2.2.2.3 Data Recording System. A digital integration system
compatible with the output voltage range of the ELCD. The recorder
must have the capability to start and stop integration at points
selected by the operator or it shall be capable of performing the
“integration by slices” technique.
7.0 Reagents and Standards
7.1 Sampling.
7.1.1 Polyethylene Glycol (PEG). Ninety-eight percent pure with
an average molecular weight of 400. Before using the PEG, remove
any organic compounds that might be detected as volatile organics
by heating it to 120 °C (248 °F) and purging it with nitrogen at a
flow rate of 1 to 2 L/min (0.04 to 0.07 ft 3/min) for 2 hours. The
cleaned PEG must be stored under a 1 to 2 L/min (0.04 to 0.07 ft
3/min) nitrogen purge until use. The purge apparatus is shown in
Figure 25D-4.
7.2 Analysis.
7.2.1 Sample Separation. The following are required for the
sample purging step.
7.2.1.1 PEG. Same as section 7.1.1.
7.2.1.2 Purge Gas. Zero grade nitrogen (N2), containing less
than 1 ppm carbon.
7.2.2 Volatile Organics Measurement. The following are required
for measuring the VO concentration.
7.2.2.1 Hydrogen (H2). Zero grade H2, 99.999 percent pure.
7.2.2.2 Combustion Gas. Zero grade air or oxygen as required by
the FID.
7.2.2.3 Calibration Gas. Pressurized gas cylinder containing 10
percent propane and 1 percent 1,1-dichloroethylene by volume in
nitrogen.
7.2.2.4 Water. Deionized distilled water that conforms to
American Society for Testing and Materials Specification D 1193-74,
Type 3, is required for analysis. At the option of the analyst, the
KMnO4 test for oxidizable organic matter may be omitted when high
concentrations are not expected to be present.
7.2.2.5 1-Propanol. ACS grade or better. Electrolyte Solution.
For use in the ELCD.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Sampling.
8.1.1 Sampling Plan Design and Development. Use the procedures
in chapter nine of Reference 1 in section 16 as guidance in
developing a sampling plan.
8.1.2 Single Phase or Well-mixed Waste.
8.1.2.1 Install a sampling tap to obtain the sample at a point
which is most representative of the unexposed waste (where the
waste has had minimum opportunity to volatilize to the atmosphere).
Assemble the sampling apparatus as shown in Figure 25D-5.
8.1.2.2 Prepare the sampling containers as follows: Pour 30 mL
of clean PEG into the container. PEG will reduce but not eliminate
the loss of organics during sample collection. Weigh the sample
container with the screw cap, the PEG, and any labels to the
nearest 0.01 g and record the weight (mst). Store the containers in
an ice bath until 1 hour before sampling (PEG will solidify at ice
bath temperatures; allow the containers to reach room temperature
before sampling).
8.1.2.3 Begin sampling by purging the sample lines and cooling
coil with at least four volumes of waste. Collect the purged
material in a separate container and dispose of it properly.
8.1.2.4 After purging, stop the sample flow and direct the
sampling tube to a preweighed sample container, prepared as
described in section 8.1.2.2. Keep the tip of the tube below the
surface of the PEG during sampling to minimize contact with the
atmosphere. Sample at a flow rate such that the temperature of the
waste is less than 10 °C (50 °F). Fill the sample container and
immediately cap it (within 5 seconds) so that a minimum headspace
exists in the container. Store immediately in a cooler and cover
with ice.
8.1.3 Multiple-phase Waste. Collect a 10 g sample of each phase
of waste generated using the procedures described in section 8.1.2
or 8.1.5. Each phase of the waste shall be analyzed as a separate
sample. Calculate the weighted average VO concentration of the
waste using Equation 25D-13 (Section 12.14).
8.1.4 Solid waste. Add approximately 10 g of the solid waste to
a container prepared in the manner described in section 8.1.2.2,
minimizing headspace. Cap and chill immediately.
8.1.5 Alternative to Tap Installation. If tap installation is
impractical or impossible, fill a large, clean, empty container by
submerging the container into the waste below the surface of the
waste. Immediately fill a container prepared in the manner
described in section 8.1.2.2 with approximately 10 g of the waste
collected in the large container. Minimize headspace, cap and chill
immediately.
8.1.6 Alternative sampling techniques may be used upon the
approval of the Administrator.
8.2 Sample Recovery.
8.2.1 Assemble the purging apparatus as shown in Figures 25D-1
and 25D-2. The oven shall be heated to 75 ±2 °C (167 ±3.6 °F). The
sampling lines leading from the oven to the detectors shall be
heated to 120 ±10 °C (248 ±18 °F) with no cold spots. The flame
ionization detector shall be operated with a heated block. Adjust
the purging lance so that it reaches the bottom of the chamber.
8.2.2 Remove the sample container from the cooler, and wipe the
exterior of the container to remove any extraneous ice, water, or
other debris. Reweigh the sample container to the nearest 0.01 g,
and record the weight (msf). Pour the contents of the sample
container into the purging flask, rinse the sample container three
times with a total of 20 mL of PEG (since the sample container
originally held 30 mL of PEG, the total volume of PEG added to the
purging flask will be 50 mL), transferring the rinsings to the
purging flask after each rinse. Cap purging flask between rinses.
The total volume of PEG in the purging flask shall be 50 mL. Add 50
mL of water to the purging flask.
9.0 Quality Control
9.1 Quality Control Samples. If audit samples are not available,
prepare and analyze the two types of quality control samples (QCS)
listed in Sections 9.1.1 and 9.1.2. Before placing the system in
operation, after a shutdown of greater than six months, and after
any major modifications, analyze each QCS in triplicate. For each
detector, calculate the percent recovery by dividing measured
concentration by theoretical concentration and multiplying by 100.
Determine the mean percent recovery for each detector for each QCS
triplicate analysis. The RSD for any triplicate analysis shall be
≤10 percent. For QCS 1 (methylene chloride), the percent recovery
shall be ≥90 percent for carbon as methane, and ≥55 percent for
chlorine as chloride. For QCS 2 (1,3-dichloro-2-propanol), the
percent recovery shall be ≤15 percent for carbon as methane, and ≤6
percent for chlorine as chloride. If the analytical system does not
meet the above-mentioned criteria for both detectors, check the
system parameters (temperature, system pressure, purge rate, etc.),
correct the problem, and repeat the triplicate analysis of each
QCS.
9.1.1 QCS 1, Methylene Chloride. Prepare a stock solution by
weighing, to the nearest 0.1 mg, 55 µL of HPLC grade methylene
chloride in a tared 5 mL volumetric flask. Record the weight in
milligrams, dilute to 5 mL with cleaned PEG, and inject 100 µL of
the stock solution into a sample prepared as a water blank (50 mL
of cleaned PEG and 60 mL of water in the purging flask). Analyze
the QCS according to the procedures described in sections 10.2 and
10.3, excluding section 10.2.2. To calculate the theoretical carbon
concentration (in mg) in QCS 1, multiply mg of methylene chloride
in the stock solution by 3.777 × 10−3. To calculate the theoretical
chlorine concentration (in mg) in QCS 1, multiply mg of methylene
chloride in the stock solution by 1.670 × 10−2.
9.1.2 QCS 2, 1,3-dichloro-2-propanol. Prepare a stock solution
by weighing, to the nearest 0.1 mg, 60 µL of high purity grade
1,3-dichloro-2-propanol in a tared 5 mL volumetric flask. Record
the weight in milligrams, dilute to 5 mL with cleaned PEG, and
inject 100 µL of the stock solution into a sample prepared as a
water blank (50 mL of cleaned PEG and 60 mL of water in the purging
flask). Analyze the QCS according to the procedures described in
sections 10.2 and 10.3, excluding section 10.2.2. To calculate the
theoretical carbon concentration (in mg) in QCS 2, multiply mg of
1,3-dichloro-2-propanol in the stock solution by 7.461 × 10−3. To
calculate the theoretical chlorine concentration (in mg) in QCS 2,
multiply mg of 1,3-dichloro-2-propanol in the stock solution by
1.099 × 10−2.
9.1.3 Routine QCS Analysis. For each set of compliance samples
(in this context, set is per facility, per compliance test),
analyze one QCS 1 and one QCS 2 sample. The percent recovery for
each sample for each detector shall be ±13 percent of the mean
recovery established for the most recent set of QCS triplicate
analysis (Section 9.4). If the sample does not meet this criteria,
check the system components and analyze another QCS 1 and 2 until a
single set of QCS meet the ±13 percent criteria.
10.0 Calibration and Standardization
10.1 Initial Performance Check of Purging System. Before placing
the system in operation, after a shutdown of greater than six
months, after any major modifications, and at least once per month
during continuous operation, conduct the linearity checks described
in sections 10.1.1 and 10.1.2. Install calibration gas at the
three-way calibration gas valve. See Figure 25D-1.
10.1.1 Linearity Check Procedure. Using the calibration standard
described in section 7.2.2.3 and by varying the injection time, it
is possible to calibrate at multiple concentration levels. Use
Equation 25D-3 to calculate three sets of calibration gas flow
rates and run times needed to introduce a total mass of carbon, as
methane, (mc) of 1, 5, and 10 mg into the system (low, medium and
high FID calibration, respectively). Use Equation 25D-4 to
calculate three sets of calibration gas flow rates and run times
needed to introduce a total chloride mass (mch) of 1, 5, and 10 mg
into the system (low, medium and high ELCD calibration,
respectively). With the system operating in standby mode, allow the
FID and the ELCD to establish a stable baseline. Set the secondary
pressure regulator of the calibration gas cylinder to the same
pressure as the purge gas cylinder and set the proper flow rate
with the calibration flow controller (see Figure 25D-1). The
calibration gas flow rate can be measured with a flowmeter attached
to the vent position of the calibration gas valve. Set the four-way
bypass valve to standby position so that the calibration gas flows
through the coalescing filter only. Inject the calibration gas by
turning the calibration gas valve from vent position to inject
position. Continue the calibration gas flow for the appropriate
period of time before switching the calibration valve to vent
position. Continue recording the response of the FID and the ELCD
for 5 min after switching off calibration gas flow. Make triplicate
injections of all six levels of calibration.
10.1.2 Linearity Criteria. Calculate the average response factor
(Equations 25D-5 and 25D-6) and the relative standard deviation
(RSD) (Equation 25D-10) at each level of the calibration curve for
both detectors. Calculate the overall mean of the three response
factor averages for each detector. The FID linearity is acceptable
if each response factor is within 5 percent of the overall mean and
if the RSD for each set of triplicate injections is less than 5
percent. The ELCD linearity is acceptable if each response factor
is within 10 percent of the overall mean and if the RSD for each
set of triplicate injections is less than 10 percent. Record the
overall mean value of the response factors for the FID and the
ELCD. If the calibration for either the FID or the ELCD does not
meet the criteria, correct the detector/system problem and repeat
sections 10.1.1 and 10.1.2.
10.2 Daily Calibrations.
10.2.1 Daily Linearity Check. Follow the procedures outlined in
section 10.1.1 to analyze the medium level calibration for both the
FID and the ELCD in duplicate at the start of the day. Calculate
the response factors and the RSDs for each detector. For the FID,
the calibration is acceptable if the average response factor is
within 5 percent of the overall mean response factor (Section
10.1.2) and if the RSD for the duplicate injection is less than 5
percent. For the ELCD, the calibration is acceptable if the average
response factor is within 10 percent of the overall mean response
factor (Section 10.1.2) and if the RSD for the duplicate injection
is less than 10 percent. If the calibration for either the FID or
the ELCD does not meet the criteria, correct the detector/system
problem and repeat sections 10.1.1 and 10.1.2.
10.2.2 Calibration Range Check.
10.2.2.1 If the waste concentration for either detector falls
below the range of calibration for that detector, use the procedure
outlined in section 10.1.1 to choose two calibration points that
bracket the new target concentration. Analyze each of these points
in triplicate (as outlined in section 10.1.1) and use the criteria
in section 10.1.2 to determine the linearity of the detector in
this “mini-calibration” range.
10.2.2.2 After the initial linearity check of the
mini-calibration curve, it is only necessary to test one of the
points in duplicate for the daily calibration check (in addition to
the points specified in section 10.2.1). The average daily
mini-calibration point should fit the linearity criteria specified
in section 10.2.1. If the calibration for either the FID or the
ELCD does not meet the criteria, correct the detector/system
problem and repeat the calibration procedure mentioned in the first
paragraph of section 10.2.2. A mini-calibration curve for waste
concentrations above the calibration curve for either detector is
optional.
10.3 Analytical Balance. Calibrate against standard weights.
11.0 Analysis
11.1 Sample Analysis.
11.1.1 Turn on the constant temperature chamber and allow the
temperature to equilibrate at 75 ±2 °C (167 ±3.6 °F). Turn the
four-way valve so that the purge gas bypasses the purging flask,
the purge gas flowing through the coalescing filter and to the
detectors (standby mode). Turn on the purge gas. Allow both the FID
and the ELCD to warm up until a stable baseline is achieved on each
detector. Pack the filter flask with ice. Replace ice after each
run and dispose of the waste water properly. When the temperature
of the oven reaches 75 ±2 °C (167 ±3.6 °F), start both integrators
and record baseline. After 1 min, turn the four-way valve so that
the purge gas flows through the purging flask, to the coalescing
filter and to the sample splitters (purge mode). Continue recording
the response of the FID and the ELCD. Monitor the readings of the
pressure gauge and the rotameter. If the readings fall below
established setpoints, stop the purging, determine the source of
the leak, and resolve the problem before resuming. Leaks detected
during a sampling period invalidate that sample.
11.1.2 As the purging continues, monitor the output of the
detectors to make certain that the analysis is proceeding correctly
and that the results are being properly recorded. Every 10 minutes
read and record the purge flow rate, the pressure and the chamber
temperature. Continue the purging for 30 minutes.
11.1.3 For each detector output, integrate over the entire area
of the peak starting at 1 minute and continuing until the end of
the run. Subtract the established baseline area from the peak area.
Record the corrected area of the peak. See Figure 25D-6 for an
example integration.
11.2 Water Blank. A water blank shall be analyzed for each batch
of cleaned PEG prepared. Transfer about 60 mL of water into the
purging flask. Add 50 mL of the cleaned PEG to the purging flask.
Treat the blank as described in sections 8.2 and 8.3, excluding
section 8.2.2. Calculate the concentration of carbon and chlorine
in the blank sample (assume 10 g of waste as the mass). A VO
concentration equivalent to ≤10 percent of the applicable standard
may be subtracted from the measured VO concentration of the waste
samples. Include all blank results and documentation in the test
report.
12.0 Data Analysis and Calculations
12.1 Nomenclature.
Ab = Area under the water blank response curve, counts. Ac = Area
under the calibration response curve, counts. As = Area under the
sample response curve, counts. C = Concentration of volatile
organics in the sample, ppmw. Cc = Concentration of carbon, as
methane, in the calibration gas, mg/L. Cch = Concentration of
chloride in the calibration gas, mg/L. Cj = VO concentration of
phase j, ppmw. DRt = Average daily response factor of the FID, mg
CH4/counts. Drth = Average daily response factor of the ELCD, mg
Cl−/counts. Fj = Weight fraction of phase j present in the waste.
mc = Mass of carbon, as methane, in a calibration run, mg. mch =
Mass of chloride in a calibration run, mg. ms = Mass of the waste
sample, g. msc = Mass of carbon, as methane, in the sample, mg. msf
= Mass of sample container and waste sample, g. msh = Mass of
chloride in the sample, mg. mst = Mass of sample container prior to
sampling, g. mVO = Mass of volatile organics in the sample, mg. n =
Total number of phases present in the waste. Pp = Percent propane
in calibration gas (L/L). Pvc = Percent 1,1-dichloroethylene in
calibration gas (L/L). Qc = Flow rate of calibration gas, L/min. tc
= Length of time standard gas is delivered to the analyzer, min. W
= Weighted average VO concentration, ppmw.
12.2 Concentration of Carbon, as Methane, in the Calibration
Gas.
12.3 Concentration of Chloride in the Calibration Gas.
12.4 Mass of Carbon, as Methane, in a Calibration Run.
12.5 Mass of Chloride in a Calibration Run.
12.6 FID Response Factor, mg/counts.
12.7 ELCD Response Factor, mg/counts.
12.8 Mass of Carbon in the Sample.
12.9 Mass of Chloride in the Sample.
12.10 Mass of Volatile Organics in the Sample.
12.11 Relative Standard Deviation.
12.12 Mass of Sample.
12.13 Concentration of Volatile Organics in Waste.
12.14 Weighted Average VO Concentration of Multi-phase
Waste.
1. “Test Methods for Evaluating Solid Waste, Physical/Chemistry
Methods”, U.S. Environmental Protection Agency. Publication SW-846,
3rd Edition, November 1986 as amended by Update I, November
1990.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 25E -
Determination of Vapor Phase Organic Concentration in Waste Samples
Note:
Performance of this method should not be attempted by persons
unfamiliar with the operation of a flame ionization detector (FID)
nor by those who are unfamiliar with source sampling because
knowledge beyond the scope of this presentation is required. This
method is not inclusive with respect to specifications
(e.g., reagents and standards) and calibration procedures.
Some material is incorporated by reference from other methods.
Therefore, to obtain reliable results, persons using this method
should have a thorough knowledge of at least the following
additional test methods: Method 106, part 61, Appendix B, and
Method 18, part 60, Appendix A.
1.0 Scope and Application
1.1 Applicability. This method is applicable for determining the
vapor pressure of waste cited by an applicable regulation.
1.2 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 The headspace vapor of the sample is analyzed for carbon
content by a headspace analyzer, which uses an FID.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 The analyst shall select the operating parameters best
suited to the requirements for a particular analysis. The analyst
shall produce confirming data through an adequate supplemental
analytical technique and have the data available for review by the
Administrator.
5.0 Safety [Reserved] 6.0 Equipment and Supplies
6.1 Sampling. The following equipment is required:
6.1.1 Sample Containers. Vials, glass, with butyl rubber septa,
Perkin-Elmer Corporation Numbers 0105-0129 (glass vials), B001-0728
(gray butyl rubber septum, plug style), 0105-0131 (butyl rubber
septa), or equivalent. The seal must be made from butyl rubber.
Silicone rubber seals are not acceptable.
6.1.2 Vial Sealer. Perkin-Elmer Number 105-0106, or
equivalent.
6.1.3 Gas-Tight Syringe. Perkin-Elmer Number 00230117, or
equivalent.
6.1.4 The following equipment is required for sampling.
6.1.4.1 Tap.
6.1.4.2 Tubing. Teflon, 0.25-in. ID.
Note:
Mention of trade names or specific products does not constitute
endorsement by the Environmental Protection Agency.
6.1.4.3 Cooling Coil. Stainless steel (304), 0.25 in.-ID,
equipped with a thermocouple at the coil outlet.
6.2 Analysis. The following equipment is required.
6.2.1 Balanced Pressure Headspace Sampler. Perkin-Elmer HS-6,
HS-100, or equivalent, equipped with a glass bead column instead of
a chromatographic column.
6.2.2 FID. An FID meeting the following specifications is
required.
6.2.2.1 Linearity. A linear response (±5 percent) over the
operating range as demonstrated by the procedures established in
section 10.2.
6.2.2.2 Range. A full scale range of 1 to 10,000 parts per
million (ppm) propane (C3H8). Signal attenuators shall be available
to produce a minimum signal response of 10 percent of full
scale.
6.2.3 Data Recording System. Analog strip chart recorder or
digital integration system compatible with the FID for permanently
recording the output of the detector.
6.2.4 Temperature Sensor. Capable of reading temperatures in the
range of 30 to 60 °C (86 to 140 °F) with an accuracy of ±0.1 °C
(±0.2 °F).
7.0 Reagents and Standards
7.1 Analysis. The following items are required for analysis.
7.1.1 Hydrogen (H2). Zero grade hydrogen, as required by the
FID.
7.1.2 Carrier Gas. Zero grade nitrogen, containing less than 1
ppm carbon (C) and less than 1 ppm carbon dioxide.
7.1.3 Combustion Gas. Zero grade air or oxygen as required by
the FID.
7.2 Calibration and Linearity Check.
7.2.1 Stock Cylinder Gas Standard. 100 percent propane. The
manufacturer shall: (a) Certify the gas composition to be accurate
to ±3 percent or better (see section 7.2.1.1); (b) recommend a
maximum shelf life over which the gas concentration does not change
by greater than ±5 percent from the certified value; and (c) affix
the date of gas cylinder preparation, certified propane
concentration, and recommended maximum shelf life to the cylinder
before shipment to the buyer.
7.2.1.1 Cylinder Standards Certification. The manufacturer shall
certify the concentration of the calibration gas in the cylinder by
(a) directly analyzing the cylinder and (b) calibrating his
analytical procedure on the day of cylinder analysis. To calibrate
his analytical procedure, the manufacturer shall use, as a minimum,
a three-point calibration curve.
7.2.1.2 Verification of Manufacturer's Calibration Standards.
Before using, the manufacturer shall verify each calibration
standard by (a) comparing it to gas mixtures prepared in accordance
with the procedure described in section 7.1 of Method 106 of Part
61, Appendix B, or by (b) calibrating it against Standard Reference
Materials (SRM's) prepared by the National Bureau of Standards, if
such SRM's are available. The agreement between the initially
determined concentration value and the verification concentration
value must be within ±5 percent. The manufacturer must reverify all
calibration standards on a time interval consistent with the shelf
life of the cylinder standards sold.
8.0 Sampling Collection, Preservation, Storage, and Transport
8.1 Install a sampling tap to obtain a sample at a point which
is most representative of the unexposed waste (where the waste has
had minimum opportunity to volatilize to the atmosphere). Assemble
the sampling apparatus as shown in Figure 25E-1.
8.2 Begin sampling by purging the sample lines and cooling coil
with at least four volumes of waste. Collect the purged material in
a separate container and dispose of it properly.
8.3 After purging, stop the sample flow and transfer the Teflon
sampling tube to a sample container. Sample at a flow rate such
that the temperature of the waste is <10 °C (<50 °F). Fill
the sample container halfway (±5 percent) and cap it within 5
seconds. Store immediately in a cooler and cover with ice.
8.4 Alternative sampling techniques may be used upon the
approval of the Administrator.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
10.2, 10.3
FID calibration and response
check
Ensure precision of analytical
results.
10.0 Calibration and Standardization Note:
Maintain a record of performance of each item.
10.1 Use the procedures in sections 10.2 to calibrate the
headspace analyzer and FID and check for linearity before the
system is first placed in operation, after any shutdown longer than
6 months, and after any modification of the system.
10.2 Calibration and Linearity. Use the procedures in section 10
of Method 18 of Part 60, Appendix A, to prepare the standards and
calibrate the flowmeters, using propane as the standard gas. Fill
the calibration standard vials halfway (±5 percent) with deionized
water. Purge and fill the airspace with calibration standard.
Prepare a minimum of three concentrations of calibration standards
in triplicate at concentrations that will bracket the applicable
cutoff. For a cutoff of 5.2 kPa (0.75 psi), prepare nominal
concentrations of 30,000, 50,000, and 70,000 ppm as propane. For a
cutoff of 27.6 kPa (4.0 psi), prepare nominal concentrations of
200,000, 300,000, and 400,000 ppm as propane.
10.2.1 Use the procedures in section 11.3 to measure the FID
response of each standard. Use a linear regression analysis to
calculate the values for the slope (k) and the y-intercept (b). Use
the procedures in sections 12.3 and 12.2 to test the calibration
and the linearity.
10.3 Daily FID Calibration Check. Check the calibration at the
beginning and at the end of the daily runs by using the following
procedures. Prepare 2 calibration standards at the nominal cutoff
concentration using the procedures in section 10.2. Place one at
the beginning and one at the end of the daily run. Measure the FID
response of the daily calibration standard and use the values for k
and b from the most recent calibration to calculate the
concentration of the daily standard. Use an equation similar to
25E-2 to calculate the percent difference between the daily
standard and Cs. If the difference is within 5 percent, then the
previous values for k and b can be used. Otherwise, use the
procedures in section 10.2 to recalibrate the FID.
11.0 Analytical Procedures
11.1 Allow one hour for the headspace vials to equilibrate at
the temperature specified in the regulation. Allow the FID to warm
up until a stable baseline is achieved on the detector.
11.2 Check the calibration of the FID daily using the procedures
in section 10.3.
11.3 Follow the manufacturer's recommended procedures for the
normal operation of the headspace sampler and FID.
11.4 Use the procedures in sections 12.4 and 12.5 to calculate
the vapor phase organic vapor pressure in the samples.
11.5 Monitor the output of the detector to make certain that the
results are being properly recorded.
12.0 Data Analysis and Calculations
12.1 Nomenclature.
A = Measurement of the area under the response curve, counts. b =
y-intercept of the linear regression line. Ca = Measured vapor
phase organic concentration of sample, ppm as propane. Cma =
Average measured vapor phase organic concentration of standard, ppm
as propane. Cm = Measured vapor phase organic concentration of
standard, ppm as propane. Cs = Calculated standard concentration,
ppm as propane. k = Slope of the linear regression line. Pbar =
Atmospheric pressure at analysis conditions, mm Hg (in. Hg). P* =
Organic vapor pressure in the sample, kPa (psi). PD = Percent
difference between the average measured vapor phase organic
concentration (Cm) and the calculated standard concentration (Cs).
RSD = Relative standard deviation. β = 1.333 × 10−7 kPa/[(mm
Hg)(ppm)], (4.91 × 10−7 psi/[(in. Hg)(ppm)])
12.2 Linearity. Use the following equation to calculate the
measured standard concentration for each standard vial.
12.2.1 Calculate the average measured standard concentration
(Cma) for each set of triplicate standards and use the following
equation to calculate PD between Cma and Cs. The instrument
linearity is acceptable if the PD is within five for each
standard.
12.3. Relative Standard Deviation (RSD). Use the following
equation to calculate the RSD for each triplicate set of
standards.
The calibration is acceptable if the RSD is
within five for each standard concentration.
12.4 Concentration of organics in the headspace. Use the
following equation to calculate the concentration of vapor phase
organics in each sample.
12.5 Vapor Pressure of Organics in the Headspace Sample. Use the
following equation to calculate the vapor pressure of organics in
the sample.
1. Salo, Albert E., Samuel Witz, and Robert D. MacPhee.
“Determination of Solvent Vapor Concentrations by Total Combustion
Analysis: a Comparison of Infared with Flame Ionization Detectors.
Paper No. 75-33.2. (Presented at the 68th Annual Meeting of the Air
Pollution Control Association. Boston, Massachusetts.
2. Salo, Albert E., William L. Oaks, and Robert D. MacPhee.
“Measuring the Organic Carbon Content of Source Emissions for Air
Pollution Control. Paper No. 74-190. (Presented at the 67th Annual
Meeting of the Air Pollution Control Association. Denver, Colorado.
June 9-13, 1974.) p. 25.
17.0 Tables, Diagrams, Flowcharts, and Validation Data [36 FR 24877, Dec.
23, 1971] Editorial Note:For Federal Register citations affecting
appendix A-7 to part 60, see the List of CFR sections Affected,
which appears in the Finding Aids section of the printed volume and
at www.govinfo.gov.
Appendix A-8 to Part 60 - Test Methods 26 through 30B
40:9.0.1.1.1.0.1.1.8 : Appendix A
Appendix A-8 to Part 60 - Test Methods 26 through 30B Method 26 -
Determination of Hydrogen Chloride Emissions From Stationary
Sources Method 26A - Determination of hydrogen halide and halogen
emissions from stationary sources - isokinetic method Method 27 -
Determination of vapor tightness of gasoline delivery tank using
pressure-vacuum test Method 28 - Certification and auditing of wood
heaters Method 28A - Measurement of air to fuel ratio and minimum
achievable burn rates for wood-fired appliances Method 29 -
Determination of metals emissions from stationary sources
The test methods in this appendix are referred to in § 60.8
(Performance Tests) and § 60.11 (Compliance With Standards and
Maintenance Requirements) of 40 CFR part 60, subpart A (General
Provisions). Specific uses of these test methods are described in
the standards of performance contained in the subparts, beginning
with Subpart D.
Within each standard of performance, a section title “Test
Methods and Procedures” is provided to: (1) Identify the test
methods to be used as reference methods to the facility subject to
the respective standard and (2) identify any special instructions
or conditions to be followed when applying a method to the
respective facility. Such instructions (for example, establish
sampling rates, volumes, or temperatures) are to be used either in
addition to, or as a substitute for procedures in a test method.
Similarly, for sources subject to emission monitoring requirements,
specific instructions pertaining to any use of a test method as a
reference method are provided in the subpart or in Appendix B.
Inclusion of methods in this appendix is not intended as an
endorsement or denial of their applicability to sources that are
not subject to standards of performance. The methods are
potentially applicable to other sources; however, applicability
should be confirmed by careful and appropriate evaluation of the
conditions prevalent at such sources.
The approach followed in the formulation of the test methods
involves specifications for equipment, procedures, and performance.
In concept, a performance specification approach would be
preferable in all methods because this allows the greatest
flexibility to the user. In practice, however, this approach is
impractical in most cases because performance specifications cannot
be established. Most of the methods described herein, therefore,
involve specific equipment specifications and procedures, and only
a few methods in this appendix rely on performance criteria.
Minor changes in the test methods should not necessarily affect
the validity of the results and it is recognized that alternative
and equivalent methods exist. section 60.8 provides authority for
the Administrator to specify or approve (1) equivalent methods, (2)
alternative methods, and (3) minor changes in the methodology of
the test methods. It should be clearly understood that unless
otherwise identified all such methods and changes must have prior
approval of the Administrator. An owner employing such methods or
deviations from the test methods without obtaining prior approval
does so at the risk of subsequent disapproval and retesting with
approved methods.
Within the test methods, certain specific equipment or
procedures are recognized as being acceptable or potentially
acceptable and are specifically identified in the methods. The
items identified as acceptable options may be used without approval
but must be identified in the test report. The potentially
approvable options are cited as “subject to the approval of the
Administrator” or as “or equivalent.” Such potentially approvable
techniques or alternatives may be used at the discretion of the
owner without prior approval. However, detailed descriptions for
applying these potentially approvable techniques or alternatives
are not provided in the test methods. Also, the potentially
approvable options are not necessarily acceptable in all
applications. Therefore, an owner electing to use such potentially
approvable techniques or alternatives is responsible for: (1)
assuring that the techniques or alternatives are in fact applicable
and are properly executed; (2) including a written description of
the alternative method in the test report (the written method must
be clear and must be capable of being performed without additional
instruction, and the degree of detail should be similar to the
detail contained in the test methods); and (3) providing any
rationale or supporting data necessary to show the validity of the
alternative in the particular application. Failure to meet these
requirements can result in the Administrator's disapproval of the
alternative.
Method 26 - Determination of Hydrogen Halide and Halogen Emissions
From Stationary Sources Non-Isokinetic Method 1.0 Scope and
Application
1.1 Analytes.
Analytes
CAS No.
Hydrogen Chloride
(HCl)
7647-01-0
Hydrogen Bromide
(HBr)
10035-10-6
Hydrogen Fluoride
(HF)
7664-39-3
Chlorine
(Cl2)
7882-50-5
Bromine (Br2)
7726-95-6
1.2 Applicability. This method is applicable for determining
emissions of hydrogen halides (HX) (HCl, HBr, and HF) and halogens
(X2) (Cl2 and Br2) from stationary sources when specified by the
applicable subpart. Sources, such as those controlled by wet
scrubbers, that emit acid particulate matter must be sampled using
Method 26A.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 An integrated sample is extracted from the source and passed
through a prepurged heated probe and filter into dilute sulfuric
acid and dilute sodium hydroxide solutions which collect the
gaseous hydrogen halides and halogens, respectively. The filter
collects particulate matter including halide salts but is not
routinely recovered and analyzed. The hydrogen halides are
solubilized in the acidic solution and form chloride (Cl−), bromide
(Br−), and fluoride (F−) ions. The halogens have a very low
solubility in the acidic solution and pass through to the alkaline
solution where they are hydrolyzed to form a proton (H + ), the
halide ion, and the hypohalous acid (HClO or HBrO). Sodium
thiosulfate is added in excess to the alkaline solution to assure
reaction with the hypohalous acid to form a second halide ion such
that 2 halide ions are formed for each molecule of halogen gas. The
halide ions in the separate solutions are measured by ion
chromatography (IC).
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Volatile materials, such as chlorine dioxide (ClO2) and
ammonium chloride (NH4Cl), which produce halide ions upon
dissolution during sampling are potential interferents.
Interferents for the halide measurements are the halogen gases
which disproportionate to a hydrogen halide and a hydrohalous acid
upon dissolution in water. However, the use of acidic rather than
neutral or basic solutions for collection of the hydrogen halides
greatly reduces the dissolution of any halogens passing through
this solution.
4.2 The simultaneous presence of HBr and CL2 may cause a
positive bias in the HCL result with a corresponding negative bias
in the Cl2 result as well as affecting the HBr/Br2 split.
4.3 High concentrations of nitrogen oxides (NOX) may produce
sufficient nitrate (NO3− to interfere with measurements of very low
Br− levels.
4.4 A glass wool plug should not be used to remove
particulate matter since a negative bias in the data could
result.
4.5 There is anecdotal evidence that HF may be outgassed from
new teflon components. If HF is a target analyte, then
preconditioning of new teflon components, by heating should be
considered.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user to establish appropriate safety and
health practices and determine the applicability of regulatory
limitations before performing this test method.
5.2 Corrosive Reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water for at least 15 minutes. Remove
clothing under shower and decontaminate. Treat residual chemical
burns as thermal burns.
5.2.1 Sodium Hydroxide (NaOH). Causes severe damage to eyes and
skin. Inhalation causes irritation to nose, throat, and lungs.
Reacts exothermically with limited amounts of water.
5.2.2 Sulfuric Acid (H2SO4). Rapidly destructive to body tissue.
Will cause third degree burns. Eye damage may result in blindness.
Inhalation may be fatal from spasm of the larynx, usually within 30
minutes. May cause lung tissue damage with edema. 1 mg/m 3 for 8
hours will cause lung damage or, in higher concentrations, death.
Provide ventilation to limit inhalation. Reacts violently with
metals and organics.
6.0 Equipment and Supplies Note:
Mention of trade names or specific products does not constitute
endorsement by the Environmental Protection Agency.
6.1 Sampling. The sampling train is shown in Figure 26-1, and
component parts are discussed below.
6.1.1 Probe. Borosilicate glass, approximately 3/8-in. (9-mm)
I.D. with a heating system capable of maintaining a probe gas
temperature during sampling between 120 and 134 °C (248 and 273 °F)
to prevent moisture condensation; or Teflon where stack probes are
below 210 °C. If HF is a target analyte, then preconditioning of
new teflon components by heating should be considered to prevent
potential HF outgassing. A Teflon-glass filter in a mat
configuration should be installed to remove particulate matter from
the gas stream.
6.1.2 Three-way Stopcock. A borosilicate-glass three-way
stopcock with a heating system to prevent moisture condensation.
The heated stopcock should connect to the outlet of the heated
filter and the inlet of the first impinger. The heating system
should be capable of preventing condensation up to the inlet of the
first impinger. Silicone grease may be used, if necessary, to
prevent leakage.
6.1.3 Impingers. Four 30-ml midget impingers with leak-free
glass connectors. Silicone grease may be used, if necessary, to
prevent leakage. For sampling at high moisture sources or for
sampling times greater than one hour, a midget impinger with a
shortened stem (such that the gas sample does not bubble through
the collected condensate) should be used in front of the first
impinger.
6.1.4 Drying Tube or Impinger. Tube or impinger, of Mae West
design, filled with 6- to 16-mesh indicating type silica gel, or
equivalent, to dry the gas sample and to protect the dry gas meter
and pump. If the silica gel has been used previously, dry at 175 °C
(350 °F) for 2 hours. New silica gel may be used as received.
Alternatively, other types of desiccants (equivalent or better) may
be used.
6.1.5 Heating System. Any heating system capable of maintaining
a temperature around the probe and filter holder between 120 and
134 °C (248 and 273 °F) during sampling, or such other temperature
as specified by an applicable subpart of the standards or approved
by the Administrator for a particular application.
6.1.6 Filter Holder and Support. The filter holder shall be made
of Teflon or quartz. The filter support shall be made of Teflon.
All Teflon filter holders and supports are available from Savillex
Corp., 5325 Hwy 101, Minnetonka, MN 55345.
6.1.7 Sample Line. Leak-free, with compatible fittings to
connect the last impinger to the needle valve.
6.1.8 Rate Meter. Rotameter, or equivalent, capable of measuring
flow rate to within 2 percent of the selected flow rate of 2
liters/min (0.07 ft 3/min).
6.1.9 Purge Pump, Purge Line, Drying Tube, Needle Valve, and
Rate Meter. Pump capable of purging the sampling probe at 2
liters/min, with drying tube, filled with silica gel or equivalent,
to protect pump, and a rate meter capable of measuring 0 to 5
liters/min (0.2 ft 3/min).
6.1.10 Stopcock Grease, Valve, Pump, Volume Meter, Barometer,
and Vacuum Gauge. Same as in Method 6, sections 6.1.1.4, 6.1.1.7,
6.1.1.8, 6.1.1.10, 6.1.2, and 6.1.3.
6.1.11 Temperature Measuring Devices. Temperature sensors to
monitor the temperature of the probe and to monitor the temperature
of the sampling system from the outlet of the probe to the inlet of
the first impinger.
6.1.12 Ice Water Bath. To minimize loss of absorbing
solution.
6.2 Sample Recovery.
6.2.1 Wash Bottles. Polyethylene or glass, 500-ml or larger,
two.
6.2.2 Storage Containers. 100- or 250-ml, high-density
polyethylene or glass sample storage containers with Teflon screw
cap liners to store impinger samples.
6.3 Sample Preparation and Analysis. The materials required for
volumetric dilution and chromatographic analysis of samples are
described below.
6.3.1 Volumetric Flasks. Class A, 100-ml size.
6.3.2 Volumetric Pipets. Class A, assortment. To dilute samples
to the calibration range of the ion chromatograph.
6.3.3 Ion Chromatograph (IC). Suppressed or non-suppressed, with
a conductivity detector and electronic integrator operating in the
peak area mode. Other detectors, strip chart recorders, and peak
height measurements may be used.
7.0 Reagents and Standards Note:
Unless otherwise indicated, all reagents must conform to the
specifications established by the Committee on Analytical Reagents
of the American Chemical Society (ACS reagent grade). When such
specifications are not available, the best available grade shall be
used.
7.1 Sampling.
7.1.1 Filter. A 25-mm (1 in) (or other size) Teflon glass mat,
Pallflex TX40HI75 (Pallflex Inc., 125 Kennedy Drive, Putnam, CT
06260). This filter is in a mat configuration to prevent fine
particulate matter from entering the sampling train. Its
composition is 75% Teflon/25% borosilicate glass. Other filters may
be used, but they must be in a mat (as opposed to a laminate)
configuration and contain at least 75% Teflon. For practical rather
than scientific reasons, when the stack gas temperature exceeds 210
°C (410 °F) and the HCl concentration is greater than 20 ppm, a
quartz-fiber filter may be used since Teflon becomes unstable above
this temperature.
7.1.2 Water. Deionized, distilled water that conforms to
American Society of Testing and Materials (ASTM) Specification D
1193-77 or 91, Type 3 (incorporated by reference - see §
60.17).
7.1.3 Acidic Absorbing Solution, 0.1 N Sulfuric Acid (H2SO4). To
prepare 100 ml of the absorbing solution for the front impinger
pair, slowly add 0.28 ml of concentrated H2SO4 to about 90 ml of
water while stirring, and adjust the final volume to 100 ml using
additional water. Shake well to mix the solution.
7.1.4 Silica Gel. Indicating type, 6 to 16 mesh. If previously
used, dry at 180 °C (350 °F) for 2 hours. New silica gel may be
used as received. Alternatively, other types of desiccants may be
used, subject to the approval of the Administrator.
7.1.5 Alkaline Adsorbing Solution, 0.1 N Sodium Hydroxide
(NaOH). To prepare 100 ml of the scrubber solution for the third
and fourth impinger, dissolve 0.40 g of solid NaOH in about 90 ml
of water, and adjust the final solution volume to 100 ml using
additional water. Shake well to mix the solution.
7.1.6 Sodium Thiosulfate (Na2S2O3 5 H2O)
7.2 Sample Preparation and Analysis.
7.2.1 Water. Same as in section 7.1.2.
7.2.2 Absorbing Solution Blanks. A separate blank solution of
each absorbing reagent should be prepared for analysis with the
field samples. Dilute 30 ml of each absorbing solution to
approximately the same final volume as the field samples using the
blank sample of rinse water.
7.2.3 Halide Salt Stock Standard Solutions. Prepare concentrated
stock solutions from reagent grade sodium chloride (NaCl), sodium
bromide (NaBr), and sodium fluoride (NaF). Each must be dried at
110 °C (230 °F) for two or more hours and then cooled to room
temperature in a desiccator immediately before weighing. Accurately
weigh 1.6 to 1.7 g of the dried NaCl to within 0.1 mg, dissolve in
water, and dilute to 1 liter. Calculate the exact Cl− concentration
using Equation 26-1 in section 12.2. In a similar manner,
accurately weigh and solubilize 1.2 to 1.3 g of dried NaBr and 2.2
to 2.3 g of NaF to make 1-liter solutions. Use Equations 26-2 and
26-3 in section 12.2, to calculate the Br− and F− concentrations.
Alternately, solutions containing a nominal certified concentration
of 1000 mg/l NaCl are commercially available as convenient stock
solutions from which standards can be made by appropriate
volumetric dilution. Refrigerate the stock standard solutions and
store no longer than one month.
7.2.4 Chromatographic Eluent. Effective eluents for
nonsuppressed IC using a resin-or silica-based weak ion exchange
column are a 4 mM potassium hydrogen phthalate solution, adjusted
to pH 4.0 using a saturated sodium borate solution, and a 4 mM
4-hydroxy benzoate solution, adjusted to pH 8.6 using 1 N NaOH. An
effective eluent for suppressed ion chromatography is a solution
containing 3 mM sodium bicarbonate and 2.4 mM sodium carbonate.
Other dilute solutions buffered to a similar pH and containing no
interfering ions may be used. When using suppressed ion
chromatography, if the “water dip” resulting from sample injection
interferes with the chloride peak, use a 2 mM NaOH/2.4 mM sodium
bicarbonate eluent.
8.0 Sample Collection, Preservation, Storage, and Transport Note:
Because of the complexity of this method, testers and analyst
should be trained and experienced with the procedure to ensure
reliable results.
8.1 Sampling.
8.1.1 Preparation of Collection Train. Prepare the sampling
train as follows: Pour 15 ml of the acidic absorbing solution into
each one of the first pair of impingers, and 15 ml of the alkaline
absorbing solution into each one of the second pair of impingers.
Connect the impingers in series with the knockout impinger first,
if used, followed by the two impingers containing the acidic
absorbing solution and the two impingers containing the alkaline
absorbing solution. Place a fresh charge of silica gel, or
equivalent, in the drying tube or impinger at the end of the
impinger train.
8.1.2 Adjust the probe temperature and the temperature of the
filter and the stopcock (i.e., the heated area in Figure
26-1) to a temperature sufficient to prevent water condensation.
This temperature must be maintained between 120 and 134 °C (248 and
273 °F). The temperature should be monitored throughout a sampling
run to ensure that the desired temperature is maintained. It is
important to maintain a temperature around the probe and filter in
this range since it is extremely difficult to purge acid gases off
these components. (These components are not quantitatively
recovered and, hence, any collection of acid gases on these
components would result in potential under reporting of these
emissions. The applicable subparts may specify alternative higher
temperatures.)
8.1.3 Leak-Check Procedure.
8.1.3.1 Sampling Train. A leak-check prior to the sampling run
is optional; however, a leak-check after the sampling run is
mandatory. The leak-check procedure is as follows: Temporarily
attach a suitable [e.g., 0-40 cc/min (0-2.4 in 3/min)]
rotameter to the outlet of the dry gas meter and place a vacuum
gauge at or near the probe inlet. Plug the probe inlet, pull a
vacuum of at least 250 mm Hg (10 in. Hg), and note the flow rate as
indicated by the rotameter. A leakage rate not in excess of 2
percent of the average sampling rate is acceptable.
Note:
Carefully release the probe inlet plug before turning off the
pump.
8.1.3.2 Pump. It is suggested (not mandatory) that the pump be
leak-checked separately, either prior to or after the sampling run.
If done prior to the sampling run, the pump leak-check shall
precede the leak-check of the sampling train described immediately
above; if done after the sampling run, the pump leak-check shall
follow the train leak-check. To leak-check the pump, proceed as
follows: Disconnect the drying tube from the probe-impinger
assembly. Place a vacuum gauge at the inlet to either the drying
tube or pump, pull a vacuum of 250 mm (10 in) Hg, plug or pinch off
the outlet of the flow meter, and then turn off the pump. The
vacuum should remain stable for at least 30 sec. Other leak-check
procedures may be used, subject to the approval of the
Administrator, U.S. Environmental Protection Agency.
8.1.4 Purge Procedure. Immediately before sampling, connect the
purge line to the stopcock, and turn the stopcock to permit the
purge pump to purge the probe (see Figure 1A of Figure 26-1). Turn
on the purge pump, and adjust the purge rate to 2 liters/min (0.07
ft 3/min). Purge for at least 5 minutes before sampling.
8.1.5 Sample Collection. Turn on the sampling pump, pull a
slight vacuum of approximately 25 mm Hg (1 in Hg) on the impinger
train, and turn the stopcock to permit stack gas to be pulled
through the impinger train (see Figure 1C of Figure 26-1). Adjust
the sampling rate to 2 liters/min, as indicated by the rate meter,
and maintain this rate to within 10 percent during the entire
sampling run. Take readings of the dry gas meter volume and
temperature, rate meter, and vacuum gauge at least once every five
minutes during the run. A sampling time of one hour is recommended.
Shorter sampling times may introduce a significant negative bias in
the HCl concentration. At the conclusion of the sampling run,
remove the train from the stack, cool, and perform a leak-check as
described in section 8.1.3.1.
8.2 Sample Recovery.
8.2.1 Disconnect the impingers after sampling. Quantitatively
transfer the contents of the acid impingers and the knockout
impinger, if used, to a leak-free storage bottle. Add the water
rinses of each of these impingers and connecting glassware to the
storage bottle.
8.2.2 Repeat this procedure for the alkaline impingers and
connecting glassware using a separate storage bottle. Add 25 mg of
sodium thiosulfate per the product of ppm of halogen anticipated to
be in the stack gas times the volume (dscm) of stack gas sampled
(0.7 mg per ppm-dscf).
Note:
This amount of sodium thiosulfate includes a safety factor of
approximately 5 to assure complete reaction with the hypohalous
acid to form a second Cl− ion in the alkaline solution.
8.2.3 Save portions of the absorbing reagents (0.1 N H2SO4 and
0.1 N NaOH) equivalent to the amount used in the sampling train
(these are the absorbing solution blanks described in section
7.2.2); dilute to the approximate volume of the corresponding
samples using rinse water directly from the wash bottle being used.
Add the same amount of sodium thiosulfate solution to the 0.1 N
NaOH absorbing solution blank. Also, save a portion of the rinse
water used to rinse the sampling train. Place each in a separate,
prelabeled storage bottle. The sample storage bottles should be
sealed, shaken to mix, and labeled. Mark the fluid level.
8.3 Sample Preparation for Analysis. Note the liquid levels in
the storage bottles and confirm on the analysis sheet whether or
not leakage occurred during transport. If a noticeable leakage has
occurred, either void the sample or use methods, subject to the
approval of the Administrator, to correct the final results.
Quantitatively transfer the sample solutions to 100-ml volumetric
flasks, and dilute to 100 ml with water.
9.0 Quality Control [Reserved] 10.0 Calibration and Standardization
Note:
Maintain a laboratory log of all calibrations.
10.1 Volume Metering System, Temperature Sensors, Rate Meter,
and Barometer. Same as in Method 6, sections 10.1, 10.2, 10.3, and
10.4.
10.2 Ion Chromatograph.
10.2.1 To prepare the calibration standards, dilute given
amounts (1.0 ml or greater) of the stock standard solutions to
convenient volumes, using 0.1 N H2SO4 or 0.1 N NaOH, as
appropriate. Prepare at least four calibration standards for each
absorbing reagent containing the appropriate stock solutions such
that they are within the linear range of the field samples.
10.2.2 Using one of the standards in each series, ensure
adequate baseline separation for the peaks of interest.
10.2.3 Inject the appropriate series of calibration standards,
starting with the lowest concentration standard first both before
and after injection of the quality control check sample, reagent
blanks, and field samples. This allows compensation for any
instrument drift occurring during sample analysis. The values from
duplicate injections of these calibration samples should agree
within 5 percent of their mean for the analysis to be valid.
10.2.4 Determine the peak areas, or heights, for the standards
and plot individual values versus halide ion concentrations in
µg/ml.
10.2.5 Draw a smooth curve through the points. Use linear
regression to calculate a formula describing the resulting linear
curve.
11.0 Analytical Procedures
11.1 Sample Analysis.
11.1.1 The IC conditions will depend upon analytical column type
and whether suppressed or non-suppressed IC is used. An example
chromatogram from a non-suppressed system using a 150-mm Hamilton
PRP-X100 anion column, a 2 ml/min flow rate of a 4 mM 4-hydroxy
benzoate solution adjusted to a pH of 8.6 using 1 N NaOH, a 50 µl
sample loop, and a conductivity detector set on 1.0 µS full scale
is shown in Figure 26-2.
11.1.2 Before sample analysis, establish a stable baseline.
Next, inject a sample of water, and determine if any Cl−, Br−, or
F− appears in the chromatogram. If any of these ions are present,
repeat the load/injection procedure until they are no longer
present. Analysis of the acid and alkaline absorbing solution
samples requires separate standard calibration curves; prepare each
according to section 10.2. Ensure adequate baseline separation of
the analyses.
11.1.3 Between injections of the appropriate series of
calibration standards, inject in duplicate the reagent blanks,
quality control sample, and the field samples. Measure the areas or
heights of the Cl−, Br−, and F− peaks. Use the mean response of the
duplicate injections to determine the concentrations of the field
samples and reagent blanks using the linear calibration curve. The
values from duplicate injections should agree within 5 percent of
their mean for the analysis to be valid. If the values of duplicate
injections are not within 5 percent of the mean, the duplicate
injections shall be repeated and all four values used to determine
the average response. Dilute any sample and the blank with equal
volumes of water if the concentration exceeds that of the highest
standard.
12.0 Data Analysis and Calculations Note:
Retain at least one extra decimal figure beyond those contained
in the available data in intermediate calculations, and round off
only the final answer appropriately.
12.1 Nomenclature.
BX− = Mass concentration of applicable absorbing solution blank, µg
halide ion (Cl−, Br−, F−) /ml, not to exceed 1 µg/ml which is 10
times the published analytical detection limit of 0.1 µg/ml. C =
Concentration of hydrogen halide (HX) or halogen (X2), dry basis,
mg/dscm. K = 10−3 mg/µg. KHCl = 1.028 (µg HCl/µg-mole)/(µg
Cl−/µg-mole). KHBr = 1.013 (µg HBr/µg-mole)/(µg Br−/µg-mole). KHF =
1.053 (µg HF/µg-mole)/(µg F−/µg-mole). mHX = Mass of HCl, HBr, or
HF in sample, µg. mX2 = Mass of Cl2 or Br2 in sample, µg. SX− =
Analysis of sample, µg halide ion (Cl−, Br−, F−)/ml. Vm(std) = Dry
gas volume measured by the dry gas meter, corrected to standard
conditions, dscm. Vs = Volume of filtered and diluted sample, ml.
12.2 Calculate the exact Cl−, Br−, and F− concentration in the
halide salt stock standard solutions using the following
equations.
12.3 Sample Volume, Dry Basis, Corrected to Standard Conditions.
Calculate the sample volume using Eq. 6-1 of Method 6.
12.4 Total µg HCl, HBr, or HF Per Sample.
12.5 Total µg Cl2 or Br2 Per Sample.
12.6 Concentration of Hydrogen Halide or Halogen in Flue
Gas.
13.0 Method Performance
13.1 Precision and Bias. The within-laboratory relative standard
deviations are 6.2 and 3.2 percent at HCl concentrations of 3.9 and
15.3 ppm, respectively. The method does not exhibit a bias to Cl2
when sampling at concentrations less than 50 ppm.
13.2 Sample Stability. The collected Cl−samples can be stored
for up to 4 weeks.
13.3 Detection Limit. A typical IC instrumental detection limit
for Cl− is 0.2 µg/ml. Detection limits for the other analyses
should be similar. Assuming 50 ml liquid recovered from both the
acidified impingers, and the basic impingers, and 0.12 dscm (4.24
dscf) of stack gas sampled, then the analytical detection limit in
the stack gas would be about 0.05 ppm for HCl and Cl2,
respectively.
Method 26A. Method 26A, which uses isokinetic sampling
equipment, is an acceptable alternative to Method 26.
17.0 References
1. Steinsberger, S. C. and J. H. Margeson, “Laboratory and Field
Evaluation of a Methodology for Determination of Hydrogen Chloride
Emissions from Municipal and Hazardous Waste Incinerators,” U.S.
Environmental Protection Agency, Office of Research and
Development, Report No. 600/3-89/064, April 1989. Available from
the National Technical Information Service, Springfield, VA 22161
as PB89220586/AS.
2. State of California, Air Resources Board, Method 421,
“Determination of Hydrochloric Acid Emissions from Stationary
Sources,” March 18, 1987.
3. Cheney, J.L. and C.R. Fortune. Improvements in the
Methodology for Measuring Hydrochloric Acid in Combustion Source
Emissions. J. Environ. Sci. Health. A19(3): 337-350.
1984.
4. Stern, D. A., B. M. Myatt, J. F. Lachowski, and K. T.
McGregor. Speciation of Halogen and Hydrogen Halide Compounds in
Gaseous Emissions. In: Incineration and Treatment of Hazardous
Waste: Proceedings of the 9th Annual Research Symposium,
Cincinnati, Ohio, May 2-4, 1983. Publication No. 600/9-84-015. July
1984. Available from National Technical Information Service,
Springfield, VA 22161 as PB84-234525.
5. Holm, R. D. and S. A. Barksdale. Analysis of Anions in
Combustion Products. In: Ion Chromatographic Analysis of
Environmental Pollutants. E. Sawicki, J. D. Mulik, and E.
Wittgenstein (eds.). Ann Arbor, Michigan, Ann Arbor Science
Publishers. 1978. pp. 99-110.
18.0 Tables, Diagrams, Flowcharts, and Validation Data Method 26A -
Determination of Hydrogen Halide and Halogen Emissions From
Stationary Sources Isokinetic Method Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 2, Method 5, and Method 26.
1.0 Scope and Application
1.1 Analytes.
Analytes
CAS No.
Hydrogen Chloride
(HCl)
7647-01-0
Hydrogen Bromide
(HBr)
10035-10-6
Hydrogen Fluoride
(HF)
7664-39-3
Chlorine
(Cl2)
7882-50-5
Bromine (Br2)
7726-95-6
1.2 This method is applicable for determining emissions of
hydrogen halides (HX) [HCl, HBr, and HF] and halogens (X2) [Cl2 and
Br2] from stationary sources when specified by the applicable
subpart. This method collects the emission sample isokinetically
and is therefore particularly suited for sampling at sources, such
as those controlled by wet scrubbers, emitting acid particulate
matter (e.g., hydrogen halides dissolved in water
droplets).
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 Principle. Gaseous and particulate pollutants are withdrawn
isokinetically from the source and collected in an optional
cyclone, on a filter, and in absorbing solutions. The cyclone
collects any liquid droplets and is not necessary if the source
emissions do not contain them; however, it is preferable to include
the cyclone in the sampling train to protect the filter from any
liquid present. The filter collects particulate matter including
halide salts but is not routinely recovered or analyzed. Acidic and
alkaline absorbing solutions collect the gaseous hydrogen halides
and halogens, respectively. Following sampling of emissions
containing liquid droplets, any halides/halogens dissolved in the
liquid in the cyclone and on the filter are vaporized to gas and
collected in the impingers by pulling conditioned ambient air
through the sampling train. The hydrogen halides are solubilized in
the acidic solution and form chloride (Cl−), bromide (Br−), and
fluoride (F−) ions. The halogens have a very low solubility in the
acidic solution and pass through to the alkaline solution where
they are hydrolyzed to form a proton (H + ), the halide ion, and
the hypohalous acid (HClO or HBrO). Sodium thiosulfate is added to
the alkaline solution to assure reaction with the hypohalous acid
to form a second halide ion such that 2 halide ions are formed for
each molecule of halogen gas. The halide ions in the separate
solutions are measured by ion chromatography (IC). If desired, the
particulate matter recovered from the filter and the probe is
analyzed following the procedures in Method 5.
Note:
If the tester intends to use this sampling arrangement to sample
concurrently for particulate matter, the alternative Teflon probe
liner, cyclone, and filter holder should not be used. The Teflon
filter support must be used. The tester must also meet the probe
and filter temperature requirements of both sampling trains.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Volatile materials, such as chlorine dioxide (ClO2) and
ammonium chloride (NH4Cl), which produce halide ions upon
dissolution during sampling are potential interferents.
Interferents for the halide measurements are the halogen gases
which disproportionate to a hydrogen halide and a hypohalous acid
upon dissolution in water. The use of acidic rather than neutral or
basic solutions for collection of the hydrogen halides greatly
reduces the dissolution of any halogens passing through this
solution.
4.2 The simultaneous presence of both HBr and Cl2 may cause a
positive bias in the HCl result with a corresponding negative bias
in the Cl2 result as well as affecting the HBr/Br2 split.
4.3 High concentrations of nitrogen oxides (NOX) may produce
sufficient nitrate (NO3−) to interfere with measurements of very
low Br− levels. Dissociating chloride salts (e.g., ammonium
chloride) at elevated temperatures interfere with halogen acid
measurement in this method. Maintaining particulate probe/filter
temperatures between 120 °C and 134 °C (248 °F and 273 °F)
minimizes this interference.
4.4 There is anecdotal evidence that HF may be outgassed from
new Teflon components. If HF is a target analyte then
preconditioning of new Teflon components, by heating, should be
considered.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user to establish appropriate safety and
health practices and determine the applicability of regulatory
limitations before performing this test method.
5.2 Corrosive Reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water for at least 15 minutes. Remove
clothing under shower and decontaminate. Treat residual chemical
burns as thermal burns.
5.2.1 Sodium Hydroxide (NaOH). Causes severe damage to eyes and
skin. Inhalation causes irritation to nose, throat, and lungs.
Reacts exothermically with limited amounts of water.
5.2.2 Sulfuric Acid (H2SO4). Rapidly destructive to body tissue.
Will cause third degree burns. Eye damage may result in blindness.
Inhalation may be fatal from spasm of the larynx, usually within 30
minutes. May cause lung tissue damage with edema. 1 mg/m 3 for 8
hours will cause lung damage or, in higher concentrations, death.
Provide ventilation to limit inhalation. Reacts violently with
metals and organics.
6.0. Equipment and Supplies Note:
Mention of trade names or specific products does not constitute
endorsement by the Environmental Protection Agency.
6.1 Sampling. The sampling train is shown in Figure 26A-1; the
apparatus is similar to the Method 5 train where noted as
follows:
6.1.1 Probe Nozzle. Borosilicate or quartz glass; constructed
and calibrated according to Method 5, sections 6.1.1.1 and 10.1,
and coupled to the probe liner using a Teflon union; a stainless
steel nut is recommended for this union. When the stack temperature
exceeds 210 °C (410 °F), a one-piece glass nozzle/liner assembly
must be used.
6.1.2 Probe Liner. Same as Method 5, section 6.1.1.2, except
metal liners shall not be used. Water-cooling of the stainless
steel sheath is recommended at temperatures exceeding 500 °C (932
°F). Teflon may be used in limited applications where the minimum
stack temperature exceeds 120 °C (250 °F) but never exceeds the
temperature where Teflon is estimated to become unstable
[approximately 210 °C (410 °F)].
6.1.3 Pitot Tube, Differential Pressure Gauge, Filter Heating
System, Filter Temperature Sensor with a glass or Teflon
encasement, Metering System, Barometer, Gas Density Determination
Equipment. Same as Method 5, sections 6.1.1.3, 6.1.1.4, 6.1.1.6,
6.1.1.7, 6.1.1.9, 6.1.2, and 6.1.3.
6.1.4 Cyclone (Optional). Glass or Teflon. Use of the cyclone is
required only when the sample gas stream is saturated with
moisture; however, the cyclone is recommended to protect the filter
from any liquid droplets present.
6.1.5 Filter Holder. Borosilicate or quartz glass, or Teflon
filter holder, with a Teflon filter support and a sealing gasket.
The sealing gasket shall be constructed of Teflon or equivalent
materials. The holder design shall provide a positive seal against
leakage at any point along the filter circumference. The holder
shall be attached immediately to the outlet of the cyclone.
6.1.6 Impinger Train. The following system shall be used to
determine the stack gas moisture content and to collect the
hydrogen halides and halogens: five or six impingers connected in
series with leak-free ground glass fittings or any similar
leak-free noncontaminating fittings. The first impinger shown in
Figure 26A-1 (knockout or condensate impinger) is optional and is
recommended as a water knockout trap for use under high moisture
conditions. If used, this impinger should be constructed as
described below for the alkaline impingers, but with a shortened
stem, and should contain 50 ml of 0.1 N H2SO4. The following two
impingers (acid impingers which each contain 100 ml of 0.1 N H2SO4)
shall be of the Greenburg-Smith design with the standard tip
(Method 5, section 6.1.1.8). The next two impingers (alkaline
impingers which each contain 100 ml of 0.1 N NaOH) and the last
impinger (containing silica gel) shall be of the modified
Greenburg-Smith design (Method 5, section 6.1.1.8). The condensate,
acid, and alkaline impingers shall contain known quantities of the
appropriate absorbing reagents. The last impinger shall contain a
known weight of silica gel or equivalent desiccant. Teflon
impingers are an acceptable alternative.
6.1.7 Heating System. Any heating system capable of maintaining
a temperature around the probe and filter holder between 120 and
134 °C (248 to 273 °F) during sampling, or such other temperature
as specified by an applicable subpart of the standards or approved
by the Administrator for a particular application.
6.1.8 Ambient Air Conditioning Tube (Optional). Tube tightly
packed with approximately 150 g of fresh 8 to 20 mesh sodium
hydroxide-coated silica, or equivalent, (Ascarite II has been found
suitable) to dry and remove acid gases from the ambient air used to
remove moisture from the filter and cyclone, when the cyclone is
used. The inlet and outlet ends of the tube should be packed with
at least 1-cm thickness of glass wool or filter material suitable
to prevent escape of fines. Fit one end with flexible tubing, etc.
to allow connection to probe nozzle following the test run.
6.2 Sample Recovery.
6.2.1 Probe-Liner and Probe-Nozzle Brushes, Wash Bottles, Petri
Dishes, Graduated Cylinder and/or Balance, and Rubber Policeman.
Same as Method 5, sections 6.2.1, 6.2.2, 6.2.4, 6.2.5, and
6.2.7.
6.2.2 Plastic Storage Containers. Screw-cap polypropylene or
polyethylene containers to store silica gel. High-density
polyethylene bottles with Teflon screw cap liners to store impinger
reagents, 1-liter.
6.2.3 Funnels. Glass or high-density polyethylene, to aid in
sample recovery.
6.2.4 Sample Storage Containers. High-density polyethylene or
glass sample storage containers with Teflon screw cap liners to
store impinger samples.
6.3 Sample Preparation and Analysis.
6.3.1 Volumetric Flasks. Class A, various sizes.
6.3.2 Volumetric Pipettes. Class A, assortment. To dilute
samples to calibration range of the ion chromatograph (IC).
6.3.3 Ion Chromatograph (IC). Suppressed or nonsuppressed, with
a conductivity detector and electronic integrator operating in the
peak area mode. Other detectors, a strip chart recorder, and peak
heights may be used.
7.0 Reagents and Standards Note:
Unless otherwise indicated, all reagents must conform to the
specifications established by the Committee on Analytical Reagents
of the American Chemical Society (ACS reagent grade). When such
specifications are not available, the best available grade shall be
used.
7.1 Sampling.
7.1.1 Filter. Teflon mat (e.g., Pallflex TX40HI45)
filter. When the stack gas temperature exceeds 210 °C (410 °F) a
quartz fiber filter may be used.
7.1.2 Water. Deionized, distilled water that conforms to
American Society of Testing and Materials (ASTM) Specification D
1193-77 or 91, Type 3 (incorporated by reference - see §
60.17).
7.1.3 Acidic Absorbing Solution, 0.1 N Sulfuric Acid (H2SO4). To
prepare 1 L, slowly add 2.80 ml of concentrated 17.9 M H2SO4 to
about 900 ml of water while stirring, and adjust the final volume
to 1 L using additional water. Shake well to mix the solution.
7.1.4 Silica Gel, Crushed Ice, and Stopcock Grease. Same as
Method 5, sections 7.1.2, 7.1.4, and 7.1.5, respectively.
7.1.5 Alkaline Absorbing Solution, 0.1 N Sodium Hydroxide
(NaOH). To prepare 1 L, dissolve 4.00 g of solid NaOH in about 900
ml of water and adjust the final volume to 1 L using additional
water. Shake well to mix the solution.
7.1.6 Sodium Thiosulfate, (Na2S2O33.5 H2O).
7.2 Sample Preparation and Analysis.
7.2.1 Water. Same as in section 7.1.2.
7.2.2 Absorbing Solution Blanks. A separate blank solution of
each absorbing reagent should be prepared for analysis with the
field samples. Dilute 200 ml of each absorbing solution (250 ml of
the acidic absorbing solution, if a condensate impinger is used) to
the same final volume as the field samples using the blank sample
of rinse water. If a particulate determination is conducted,
collect a blank sample of acetone.
7.2.3 Halide Salt Stock Standard Solutions. Prepare concentrated
stock solutions from reagent grade sodium chloride (NaCl), sodium
bromide (NaBr), and sodium fluoride (NaF). Each must be dried at
110 °C (230 °F) for two or more hours and then cooled to room
temperature in a desiccator immediately before weighing. Accurately
weigh 1.6 to 1.7 g of the dried NaCl to within 0.1 mg, dissolve in
water, and dilute to 1 liter. Calculate the exact Cl−concentration
using Equation 26A-1 in section 12.2. In a similar manner,
accurately weigh and solubilize 1.2 to 1.3 g of dried NaBr and 2.2
to 2.3 g of NaF to make 1-liter solutions. Use Equations 26A-2 and
26A-3 in section 12.2, to calculate the Br−and F−concentrations.
Alternately, solutions containing a nominal certified concentration
of 1000 mg/L NaCl are commercially available as convenient stock
solutions from which standards can be made by appropriate
volumetric dilution. Refrigerate the stock standard solutions and
store no longer than one month.
7.2.4 Chromatographic Eluent. Same as Method 26, section
7.2.4.
7.2.5 Water. Same as section 7.1.1.
7.2.6 Acetone. Same as Method 5, section 7.2.
8.0 Sample Collection, Preservation, Storage, and Transport Note:
Because of the complexity of this method, testers and analysts
should be trained and experienced with the procedures to ensure
reliable results.
8.1 Sampling.
8.1.1 Pretest Preparation. Follow the general procedure given in
Method 5, section 8.1, except the filter need only be desiccated
and weighed if a particulate determination will be conducted.
8.1.2 Preliminary Determinations. Same as Method 5, section
8.2.
8.1.3 Preparation of Sampling Train. Follow the general
procedure given in Method 5, section 8.1.3, except for the
following variations: Add 50 ml of 0.1 N H2SO4 to the condensate
impinger, if used. Place 100 ml of 0.1 N H2SO4 in each of the next
two impingers. Place 100 ml of 0.1 N NaOH in each of the following
two impingers. Finally, transfer approximately 200-300 g of
preweighed silica gel from its container to the last impinger. Set
up the train as in Figure 26A-1. When used, the optional cyclone is
inserted between the probe liner and filter holder and located in
the heated filter box.
8.1.4 Leak-Check Procedures. Follow the leak-check procedures
given in Method 5, sections 8.4.2 (Pretest Leak-Check), 8.4.3
(Leak-Checks During the Sample Run), and 8.4.4 (Post-Test
Leak-Check).
8.1.5 Sampling Train Operation. Follow the general procedure
given in Method 5, Section 8.5. It is important to maintain a
temperature around the probe, filter (and cyclone, if used) between
120 and 134 °C (248 and 273 °F) since it is extremely difficult to
purge acid gases off these components. (These components are not
quantitatively recovered and hence any collection of acid gases on
these components would result in potential under reporting these
emissions. The applicable subparts may specify alternative higher
temperatures.) For each run, record the data required on a data
sheet such as the one shown in Method 5, Figure 5-3. If the
condensate impinger becomes too full, it may be emptied, recharged
with 50 ml of 0.1 N H2SO4, and replaced during the sample run. The
condensate emptied must be saved and included in the measurement of
the volume of moisture collected and included in the sample for
analysis. The additional 50 ml of absorbing reagent must also be
considered in calculating the moisture. Before the sampling train
integrity is compromised by removing the impinger, conduct a
leak-check as described in Method 5, section 8.4.2.
8.1.6 Post-Test Moisture Removal (Optional). When the optional
cyclone is included in the sampling train or when liquid is visible
on the filter at the end of a sample run even in the absence of a
cyclone, perform the following procedure. Upon completion of the
test run, connect the ambient air conditioning tube at the probe
inlet and operate the train with the filter heating system between
120 and 134 °C (248 and 273 °F) at a low flow rate (e.g., ΔH
= 1 in. H2O) to vaporize any liquid and hydrogen halides in the
cyclone or on the filter and pull them through the train into the
impingers. After 30 minutes, turn off the flow, remove the
conditioning tube, and examine the cyclone and filter for any
visible liquid. If liquid is visible, repeat this step for 15
minutes and observe again. Keep repeating until the cyclone is
dry.
Note:
It is critical that this procedure is repeated until the cyclone
is completely dry.
8.2 Sample Recovery. Allow the probe to cool. When the probe can
be handled safely, wipe off all the external surfaces of the tip of
the probe nozzle and place a cap loosely over the tip to prevent
gaining or losing particulate matter. Do not cap the probe tip
tightly while the sampling train is cooling down because this will
create a vacuum in the filter holder, drawing water from the
impingers into the holder. Before moving the sampling train to the
cleanup site, remove the probe from the sample train, wipe off any
silicone grease, and cap the open outlet of the impinger train,
being careful not to lose any condensate that might be present.
Wipe off any silicone grease and cap the filter or cyclone inlet.
Remove the umbilical cord from the last impinger and cap the
impinger. If a flexible line is used between the first impinger and
the filter holder, disconnect it at the filter holder and let any
condensed water drain into the first impinger. Wipe off any
silicone grease and cap the filter holder outlet and the impinger
inlet. Ground glass stoppers, plastic caps, serum caps, Teflon
tape, Parafilm, or aluminum foil may be used to close these
openings. Transfer the probe and filter/impinger assembly to the
cleanup area. This area should be clean and protected from the
weather to minimize sample contamination or loss. Inspect the train
prior to and during disassembly and note any abnormal conditions.
Treat samples as follows:
8.2.1 Container No. 1 (Optional; Filter Catch for Particulate
Determination). Same as Method 5, section 8.7.6.1, Container No.
1.
8.2.2 Container No. 2 (Optional; Front-Half Rinse for
Particulate Determination). Same as Method 5, section 8.7.6.2,
Container No. 2.
8.2.3 Container No. 3 (Knockout and Acid Impinger Catch for
Moisture and Hydrogen Halide Determination). Disconnect the
impingers. Measure the liquid in the acid and knockout impingers to
±1 ml by using a graduated cylinder or by weighing it to ±0.5 g by
using a balance. Record the volume or weight of liquid present.
This information is required to calculate the moisture content of
the effluent gas. Quantitatively transfer this liquid to a
leak-free sample storage container. Rinse these impingers and
connecting glassware including the back portion of the filter
holder (and flexible tubing, if used) with water and add these
rinses to the storage container. Seal the container, shake to mix,
and label. The fluid level should be marked so that if any sample
is lost during transport, a correction proportional to the lost
volume can be applied. Retain rinse water and acidic absorbing
solution blanks to be analyzed with the samples.
8.2.4 Container No. 4 (Alkaline Impinger Catch for Halogen and
Moisture Determination). Measure and record the liquid in the
alkaline impingers as described in section 8.2.3. Quantitatively
transfer this liquid to a leak-free sample storage container. Rinse
these two impingers and connecting glassware with water and add
these rinses to the container. Add 25 mg of sodium thiosulfate per
ppm halogen anticipated to be in the stack gas multiplied by the
volume (dscm) of stack gas sampled (0.7 mg/ppm-dscf). Seal the
container, shake to mix, and label; mark the fluid level. Retain
alkaline absorbing solution blank to be analyzed with the
samples.
Note:
25 mg per sodium thiosulfate per ppm halogen anticipated to be
in the stack includes a safety factor of approximately 5 to assure
complete reaction with the hypohalous acid to form a second Cl− ion
in the alkaline solution.
8.2.5 Container No. 5 (Silica Gel for Moisture Determination).
Same as Method 5, section 8.7.6.3, Container No. 3.
8.2.6 Container Nos. 6 through 9 (Reagent Blanks). Save portions
of the absorbing reagents (0.1 N H2SO4 and 0.1 N NaOH) equivalent
to the amount used in the sampling train; dilute to the approximate
volume of the corresponding samples using rinse water directly from
the wash bottle being used. Add the same ratio of sodium
thiosulfate solution used in container No. 4 to the 0.1 N NaOH
absorbing reagent blank. Also, save a portion of the rinse water
alone and a portion of the acetone equivalent to the amount used to
rinse the front half of the sampling train. Place each in a
separate, prelabeled sample container.
8.2.7 Prior to shipment, recheck all sample containers to ensure
that the caps are well-secured. Seal the lids of all containers
around the circumference with Teflon tape. Ship all liquid samples
upright and all particulate filters with the particulate catch
facing upward.
9.0 Quality Control
9.1 Miscellaneous Quality Control Measures.
Section
Quality control measure
Effect
8.1.4, 10.1
Sampling equipment leak-check
and calibration
Ensure accurate measurement of
stack gas flow rate, sample volume.
9.2 Volume Metering System Checks. Same as Method 5, section
9.2.
10.0 Calibration and Standardization Note:
Maintain a laboratory log of all calibrations.
10.1 Probe Nozzle, Pitot Tube Assembly, Dry Gas Metering System,
Probe Heater, Temperature Sensors, Leak-Check of Metering System,
and Barometer. Same as Method 5, sections 10.1, 10.2, 10.3, 10.4,
10.5, 8.4.1, and 10.6, respectively.
10.2 Ion Chromatograph.
10.2.1 To prepare the calibration standards, dilute given
amounts (1.0 ml or greater) of the stock standard solutions to
convenient volumes, using 0.1 N H2SO4 or 0.1 N NaOH, as
appropriate. Prepare at least four calibration standards for each
absorbing reagent containing the three stock solutions such that
they are within the linear range of the field samples.
10.2.2 Using one of the standards in each series, ensure
adequate baseline separation for the peaks of interest.
10.2.3 Inject the appropriate series of calibration standards,
starting with the lowest concentration standard first both before
and after injection of the quality control check sample, reagent
blanks, and field samples. This allows compensation for any
instrument drift occurring during sample analysis. The values from
duplicate injections of these calibration samples should agree
within 5 percent of their mean for the analysis to be valid.
10.2.4 Determine the peak areas, or height, of the standards and
plot individual values versus halide ion concentrations in
µg/ml.
10.2.5 Draw a smooth curve through the points. Use linear
regression to calculate a formula describing the resulting linear
curve.
11.0 Analytical Procedures Note:
The liquid levels in the sample containers and confirm on the
analysis sheet whether or not leakage occurred during transport. If
a noticeable leakage has occurred, either void the sample or use
methods, subject to the approval of the Administrator, to correct
the final results.
11.1 Sample Analysis.
11.1.1 The IC conditions will depend upon analytical column type
and whether suppressed or non-suppressed IC is used. An example
chromatogram from a non-suppressed system using a 150-mm Hamilton
PRP-X100 anion column, a 2 ml/min flow rate of a 4 mM 4-hydroxy
benzoate solution adjusted to a pH of 8.6 using 1 N NaOH, a 50 µl
sample loop, and a conductivity detector set on 1.0 µS full scale
is shown in Figure 26-2.
11.1.2 Before sample analysis, establish a stable baseline.
Next, inject a sample of water, and determine if any Cl−, Br−, or
F− appears in the chromatogram. If any of these ions are present,
repeat the load/injection procedure until they are no longer
present. Analysis of the acid and alkaline absorbing solution
samples requires separate standard calibration curves; prepare each
according to section 10.2. Ensure adequate baseline separation of
the analyses.
11.1.3 Between injections of the appropriate series of
calibration standards, inject in duplicate the reagent blanks,
quality control sample, and the field samples. Measure the areas or
heights of the Cl−, Br−, and F− peaks. Use the mean response of the
duplicate injections to determine the concentrations of the field
samples and reagent blanks using the linear calibration curve. The
values from duplicate injections should agree within 5 percent of
their mean for the analysis to be valid. If the values of duplicate
injections are not within 5 percent of the mean, the duplicator
injections shall be repeated and all four values used to determine
the average response. Dilute any sample and the blank with equal
volumes of water if the concentration exceeds that of the highest
standard.
11.2 Container Nos. 1 and 2 and Acetone Blank (Optional;
Particulate Determination). Same as Method 5, sections 11.2.1 and
11.2.2, respectively.
11.3 Container No. 5. Same as Method 5, section 11.2.3 for
silica gel.
12.0 Data Analysis and Calculations Note:
Retain at least one extra decimal figure beyond those contained
in the available data in intermediate calculations, and round off
only the final answer appropriately.
12.1 Nomenclature. Same as Method 5, section 12.1. In
addition:
BX− = Mass concentration of applicable absorbing solution blank, µg
halide ion (Cl−, Br−, F−)/ml, not to exceed 1 µg/ml which is 10
times the published analytical detection limit of 0.1 µg/ml. (It is
also approximately 5 percent of the mass concentration anticipated
to result from a one hour sample at 10 ppmv HCl.) C = Concentration
of hydrogen halide (HX) or halogen (X2), dry basis, mg/dscm. K =
10−3 mg/µg. KHCl = 1.028 (µg HCl/µg-mole)/(µg Cl−/µg-mole). KHBr =
1.013 (µg HBr/µg-mole)/(µg Br−/µg-mole). KHF = 1.053 (µg
HF/µg-mole)/(µg F−/µg-mole). mHX = Mass of HCl, HBr, or HF in
sample, ug. mX2 = Mass of Cl2 or Br2 in sample, ug. SX− = Analysis
of sample, ug halide ion (Cl−, Br−, F−)/ml. Vs = Volume of filtered
and diluted sample, ml.
12.2 Calculate the exact Cl−, Br−, and F− concentration in the
halide salt stock standard solutions using the following
equations.
12.3 Average Dry Gas Meter Temperature and Average Orifice
Pressure Drop. See data sheet (Figure 5-3 of Method 5).
12.4 Dry Gas Volume. Calculate Vm(std) and adjust for leakage,
if necessary, using the equation in section 12.3 of Method 5.
12.5 Volume of Water Vapor and Moisture Content. Calculate the
volume of water vapor Vw(std) and moisture content Bws from the
data obtained in this method (Figure 5-3 of Method 5); use
Equations 5-2 and 5-3 of Method 5.
12.6 Isokinetic Variation and Acceptable Results. Use Method 5,
section 12.11.
12.7 Acetone Blank Concentration, Acetone Wash Blank Residue
Weight, Particulate Weight, and Particulate Concentration. For
particulate determination.
12.8 Total µg HCl, HBr, or HF Per Sample.
12.9 Total µg Cl2 or Br2 Per Sample.
12.10 Concentration of Hydrogen Halide or Halogen in Flue
Gas.
12.11 Stack Gas Velocity and Volumetric Flow Rate. Calculate the
average stack gas velocity and volumetric flow rate, if needed,
using data obtained in this method and the equations in sections
12.3 and 12.4 of Method 2.
13.0 Method Performance
13.1 Precision and Bias. The method has a possible measurable
negative bias below 20 ppm HCl perhaps due to reaction with small
amounts of moisture in the probe and filter. Similar bias for the
other hydrogen halides is possible.
13.2 Sample Stability. The collected Cl-samples can be stored
for up to 4 weeks for analysis for HCl and Cl2.
13.3 Detection Limit. A typical analytical detection limit for
HCl is 0.2 µg/ml. Detection limits for the other analyses should be
similar. Assuming 300 ml of liquid recovered for the acidified
impingers and a similar amounts recovered from the basic impingers,
and 1 dscm of stack gas sampled, the analytical detection limits in
the stack gas would be about 0.04 ppm for HCl and Cl2,
respectively.
1. Steinsberger, S. C. and J. H. Margeson. Laboratory and Field
Evaluation of a Methodology for Determination of Hydrogen Chloride
Emissions from Municipal and Hazardous Waste Incinerators. U.S.
Environmental Protection Agency, Office of Research and
Development. Publication No. 600/3-89/064. April 1989. Available
from National Technical Information Service, Springfield, VA 22161
as PB89220586/AS.
2. State of California Air Resources Board. Method 421 -
Determination of Hydrochloric Acid Emissions from Stationary
Sources. March 18, 1987.
3. Cheney, J.L. and C.R. Fortune. Improvements in the
Methodology for Measuring Hydrochloric Acid in Combustion Source
Emissions. J. Environ. Sci. Health. A19(3): 337-350.
1984.
4. Stern, D.A., B.M. Myatt, J.F. Lachowski, and K.T. McGregor.
Speciation of Halogen and Hydrogen Halide Compounds in Gaseous
Emissions. In: Incineration and Treatment of Hazardous Waste:
Proceedings of the 9th Annual Research Symposium, Cincinnati, Ohio,
May 2-4, 1983. Publication No. 600/9-84-015. July 1984. Available
from National Technical Information Service, Springfield, VA 22161
as PB84-234525.
5. Holm, R.D. and S.A. Barksdale. Analysis of Anions in
Combustion Products. In: Ion Chromatographic Analysis of
Environmental Pollutants, E. Sawicki, J.D. Mulik, and E.
Wittgenstein (eds.). Ann Arbor, Michigan, Ann Arbor Science
Publishers. 1978. pp. 99-110.
17.0 Tables, Diagrams, Flowcharts, and Validation Data Method 27 -
Determination of Vapor Tightness of Gasoline Delivery Tank Using
Pressure Vacuum Test 1.0 Scope and Application
1.1 Applicability. This method is applicable for the
determination of vapor tightness of a gasoline delivery collection
equipment.
2.0 Summary of Method
2.1 Pressure and vacuum are applied alternately to the
compartments of a gasoline delivery tank and the change in pressure
or vacuum is recorded after a specified period of time.
3.0 Definitions
3.1 Allowable pressure change (Δp) means the allowable
amount of decrease in pressure during the static pressure test,
within the time period t, as specified in the appropriate
regulation, in mm H2O.
3.2 Allowable vacuum change (Δv) means the allowable
amount of decrease in vacuum during the static vacuum test, within
the time period t, as specified in the appropriate regulation, in
mm H2O.
3.3 Compartment means a liquid-tight division of a
delivery tank.
3.4 Delivery tank means a container, including associated
pipes and fittings, that is attached to or forms a part of any
truck, trailer, or railcar used for the transport of gasoline.
3.5 Delivery tank vapor collection equipment means any
piping, hoses, and devices on the delivery tank used to collect and
route gasoline vapors either from the tank to a bulk terminal vapor
control system or from a bulk plant or service station into the
tank.
3.6 Gasoline means a petroleum distillate or petroleum
distillate/alcohol blend having a Reid vapor pressure of 27.6
kilopascals or greater which is used as a fuel for internal
combustion engines.
3.7 Initial pressure (Pi) means the pressure applied to
the delivery tank at the beginning of the static pressure test, as
specified in the appropriate regulation, in mm H2O.
3.8 Initial vacuum (Vi) means the vacuum applied to the
delivery tank at the beginning of the static vacuum test, as
specified in the appropriate regulation, in mm H3.
3.9 Time period of the pressure or vacuum test (t) means
the time period of the test, as specified in the appropriate
regulation, during which the change in pressure or vacuum is
monitored, in minutes.
4.0 Interferences [Reserved] 5.0 Safety
5.1 Gasoline contains several volatile organic compounds
(e.g., benzene and hexane) which presents a potential for
fire and/or explosions. It is advisable to take appropriate
precautions when testing a gasoline vessel's vapor tightness, such
as refraining from smoking and using explosion-proof equipment.
5.2 This method may involve hazardous materials, operations, and
equipment. This test method may not address all of the safety
problems associated with its use. It is the responsibility of the
user of this test method to establish appropriate safety and health
practices and determine the applicability of regulatory limitations
prior to performing this test method
6.0 Equipment and Supplies
The following equipment and supplies are required for
testing:
6.1 Pressure Source. Pump or compressed gas cylinder of air or
inert gas sufficient to pressurize the delivery tank to 500 mm (20
in.) H2O above atmospheric pressure.
6.2 Regulator. Low pressure regulator for controlling
pressurization of the delivery tank.
6.3 Vacuum Source. Vacuum pump capable of evacuating the
delivery tank to 250 mm (10 in.) H2O below atmospheric
pressure.
6.4 Pressure-Vacuum Supply Hose.
6.5 Manometer. Liquid manometer, or equivalent instrument,
capable of measuring up to 500 mm (20 in.) H2O gauge pressure with
±2.5 mm (0.1 in.) H2O precision.
6.6 Pressure-Vacuum Relief Valves. The test apparatus shall be
equipped with an inline pressure-vacuum relief valve set to
activate at 675 mm (26.6 in.) H2O above atmospheric pressure or 250
mm (10 in.) H2O below atmospheric pressure, with a capacity equal
to the pressurizing or evacuating pumps.
6.7 Test Cap for Vapor Recovery Hose. This cap shall have a tap
for manometer connection and a fitting with shut-off valve for
connection to the pressure-vacuum supply hose.
6.8 Caps for Liquid Delivery Hoses.
7.0 Reagents and Standards [Reserved] 8.0 Sample Collection,
Preservation, Storage, and Transport
8.1 Pretest Preparations.
8.1.1 Summary. Testing problems may occur due to the presence of
volatile vapors and/or temperature fluctuations inside the delivery
tank. Under these conditions, it is often difficult to obtain a
stable initial pressure at the beginning of a test, and erroneous
test results may occur. To help prevent this, it is recommended
that prior to testing, volatile vapors be removed from the tank and
the temperature inside the tank be allowed to stabilize. Because it
is not always possible to completely attain these pretest
conditions, a provision to ensure reproducible results is included.
The difference in results for two consecutive runs must meet the
criteria in sections 8.2.2.5 and 8.2.3.5.
8.1.2 Emptying of Tank. The delivery tank shall be emptied of
all liquid.
8.1.3 Purging of Vapor. As much as possible the delivery tank
shall be purged of all volatile vapors by any safe, acceptable
method. One method is to carry a load of non-volatile liquid fuel,
such as diesel or heating oil, immediately prior to the test, thus
flushing out all the volatile gasoline vapors. A second method is
to remove the volatile vapors by blowing ambient air into each tank
compartment for at least 20 minutes. This second method is usually
not as effective and often causes stabilization problems, requiring
a much longer time for stabilization during the testing.
8.1.4 Temperature Stabilization. As much as possible, the test
shall be conducted under isothermal conditions. The temperature of
the delivery tank should be allowed to equilibrate in the test
environment. During the test, the tank should be protected from
extreme environmental and temperature variability, such as direct
sunlight.
8.2 Test Procedure.
8.2.1 Preparations.
8.2.1.1 Open and close each dome cover.
8.2.1.2 Connect static electrical ground connections to the
tank. Attach the liquid delivery and vapor return hoses, remove the
liquid delivery elbows, and plug the liquid delivery fittings.
Note:
The purpose of testing the liquid delivery hoses is to detect
tears or holes that would allow liquid leakage during a delivery.
Liquid delivery hoses are not considered to be possible sources of
vapor leakage, and thus, do not have to be attached for a vapor
leakage test. Instead, a liquid delivery hose could be either
visually inspected, or filled with water to detect any liquid
leakage.
8.2.1.3 Attach the test cap to the end of the vapor recovery
hose.
8.2.1.4 Connect the pressure-vacuum supply hose and the
pressure-vacuum relief valve to the shut-off valve. Attach a
manometer to the pressure tap.
8.2.1.5 Connect compartments of the tank internally to each
other if possible. If not possible, each compartment must be tested
separately, as if it were an individual delivery tank.
8.2.2 Pressure Test.
8.2.2.1 Connect the pressure source to the pressure-vacuum
supply hose.
8.2.2.2 Open the shut-off valve in the vapor recovery hose cap.
Apply air pressure slowly, pressurize the tank to Pi, the initial
pressure specified in the regulation.
8.2.2.3 Close the shut-off and allow the pressure in the tank to
stabilize, adjusting the pressure if necessary to maintain pressure
of Pi. When the pressure stabilizes, record the time and initial
pressure.
8.2.2.4 At the end of the time period (t) specified in the
regulation, record the time and final pressure.
8.2.2.5 Repeat steps 8.2.2.2 through 8.2.2.4 until the change in
pressure for two consecutive runs agrees within 12.5 mm (0.5 in.)
H2O. Calculate the arithmetic average of the two results.
8.2.2.6 Compare the average measured change in pressure to the
allowable pressure change, Δp, specified in the regulation. If the
delivery tank does not satisfy the vapor tightness criterion
specified in the regulation, repair the sources of leakage, and
repeat the pressure test until the criterion is met.
8.2.2.7 Disconnect the pressure source from the pressure-vacuum
supply hose, and slowly open the shut-off valve to bring the tank
to atmospheric pressure.
8.2.3 Vacuum Test.
8.2.3.1 Connect the vacuum source to the pressure-vacuum supply
hose.
8.2.3.2 Open the shut-off valve in the vapor recovery hose cap.
Slowly evacuate the tank to Vi, the initial vacuum specified in the
regulation.
8.2.3.3 Close the shut-off valve and allow the pressure in the
tank to stabilize, adjusting the pressure if necessary to maintain
a vacuum of Vi. When the pressure stabilizes, record the time and
initial vacuum.
8.2.3.4 At the end of the time period specified in the
regulation (t), record the time and final vacuum.
8.2.3.5 Repeat steps 8.2.3.2 through 8.2.3.4 until the change in
vacuum for two consecutive runs agrees within 12.5 mm (0.5 in.)
H2O. Calculate the arithmetic average of the two results.
8.2.3.6 Compare the average measured change in vacuum to the
allowable vacuum change, Δv, as specified in the regulation. If the
delivery tank does not satisfy the vapor tightness criterion
specified in the regulation, repair the sources of leakage, and
repeat the vacuum test until the criterion is met.
8.2.3.7 Disconnect the vacuum source from the pressure-vacuum
supply hose, and slowly open the shut-off valve to bring the tank
to atmospheric pressure.
8.2.4 Post-Test Clean-up. Disconnect all test equipment and
return the delivery tank to its pretest condition.
9.0 Quality Control
Section(s)
Quality control measure
Effect
8.2.2.5,
8.3.3.5
Repeat test procedures until
change in pressure or vacuum for two consecutive runs agrees within
±12.5 mm (0.5 in.) H2O
Ensures data precision.
10.0 Calibration and Standardization [Reserved] 11.0 Analytical
Procedures [Reserved] 12.0 Data Analysis and Calculations
[Reserved] 13.0 Method Performance
13.1 Precision. The vapor tightness of a gasoline delivery tank
under positive or negative pressure, as measured by this method, is
precise within 12.5 mm (0.5 in.) H2O
16.1 The pumping of water into the bottom of a delivery tank is
an acceptable alternative to the pressure source described above.
Likewise, the draining of water out of the bottom of a delivery
tank may be substituted for the vacuum source. Note that some of
the specific step-by-step procedures in the method must be altered
slightly to accommodate these different pressure and vacuum
sources.
16.2 Techniques other than specified above may be used for
purging and pressurizing a delivery tank, if prior approval is
obtained from the Administrator. Such approval will be based upon
demonstrated equivalency with the above method.
17.0 References [Reserved] 18.0 Tables, Diagrams, Flowcharts, and
Validation Data [Reserved] Method 28 - Certification and Auditing
of Wood Heaters Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 1, Method 2, Method 3, Method 4,
Method 5, Method 5G, Method 5H, Method 6, Method 6C, and Method
16A.
1.0 Scope and Application
1.1 Analyte. Particulate matter (PM). No CAS number
assigned.
1.2 Applicability. This method is applicable for the
certification and auditing of wood heaters, including pellet
burning wood heaters.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 Particulate matter emissions are measured from a wood heater
burning a prepared test fuel crib in a test facility maintained at
a set of prescribed conditions. Procedures for determining burn
rates and particulate emission rates and for reducing data are
provided.
3.0 Definitions
3.1 2 × 4 or 4 × 4 means two inches by four inches or
four inches by four inches (50 mm by 100 mm or 100 mm by 100 mm),
as nominal dimensions for lumber.
3.2 Burn rate means the rate at which test fuel is
consumed in a wood heater. Measured in kilograms or lbs of wood
(dry basis) per hour (kg/hr or lb/hr).
3.3 Certification or audit test means a series of at
least four test runs conducted for certification or audit purposes
that meets the burn rate specifications in section 8.4.
3.4 Firebox means the chamber in the wood heater in which
the test fuel charge is placed and combusted.
3.5 Height means the vertical distance extending above
the loading door, if fuel could reasonably occupy that space, but
not more than 2 inches above the top (peak height) of the loading
door, to the floor of the firebox (i.e., below a permanent
grate) if the grate allows a 1-inch diameter piece of wood to pass
through the grate, or, if not, to the top of the grate. Firebox
height is not necessarily uniform but must account for variations
caused by internal baffles, air channels, or other permanent
obstructions.
3.6 Length means the longest horizontal fire chamber
dimension that is parallel to a wall of the chamber.
3.7 Pellet burning wood heater means a wood heater which
meets the following criteria: (1) The manufacturer makes no
reference to burning cord wood in advertising or other literature,
(2) the unit is safety listed for pellet fuel only, (3) the unit
operating and instruction manual must state that the use of
cordwood is prohibited by law, and (4) the unit must be
manufactured and sold including the hopper and auger combination as
integral parts.
3.8 Secondary air supply means an air supply that
introduces air to the wood heater such that the burn rate is not
altered by more than 25 percent when the secondary air supply is
adjusted during the test run. The wood heater manufacturer can
document this through design drawings that show the secondary air
is introduced only into a mixing chamber or secondary chamber
outside the firebox.
3.9 Test facility means the area in which the wood heater
is installed, operated, and sampled for emissions.
3.10 Test fuel charge means the collection of test fuel
pieces placed in the wood heater at the start of the emission test
run.
3.11 Test fuel crib means the arrangement of the test
fuel charge with the proper spacing requirements between adjacent
fuel pieces.
3.12 Test fuel loading density means the weight of the
as-fired test fuel charge per unit volume of usable firebox.
3.13 Test fuel piece means the 2 × 4 or 4 × 4 wood piece
cut to the length required for the test fuel charge and used to
construct the test fuel crib.
3.14 Test run means an individual emission test which
encompasses the time required to consume the mass of the test fuel
charge.
3.15 Usable firebox volume means the volume of the
firebox determined using its height, length, and width as defined
in this section.
3.16 Width means the shortest horizontal fire chamber
dimension that is parallel to a wall of the chamber.
3.17 Wood heater means an enclosed, woodburning appliance
capable of and intended for space heating or domestic water
heating, as defined in the applicable regulation.
4.0 Interferences [Reserved] 5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies
Same as section 6.0 of either Method 5G or Method 5H, with the
addition of the following:
6.1 Insulated Solid Pack Chimney. For installation of wood
heaters. Solid pack insulated chimneys shall have a minimum of 2.5
cm (1 in.) solid pack insulating material surrounding the entire
flue and possess a label demonstrating conformance to U.L. 103
(incorporated by reference - see § 60.17).
6.2 Platform Scale and Monitor. For monitoring of fuel load
weight change. The scale shall be capable of measuring weight to
within 0.05 kg (0.1 lb) or 1 percent of the initial test fuel
charge weight, whichever is greater.
6.3 Wood Heater Temperature Monitors. Seven, each capable of
measuring temperature to within 1.5 percent of expected absolute
temperatures.
6.4 Test Facility Temperature Monitor. A thermocouple located
centrally in a vertically oriented 150 mm (6 in.) long, 50 mm (2
in.) diameter pipe shield that is open at both ends, capable of
measuring temperature to within 1.5 percent of expected
temperatures.
6.5 Balance (optional). Balance capable of weighing the test
fuel charge to within 0.05 kg (0.1 lb).
6.6 Moisture Meter. Calibrated electrical resistance meter for
measuring test fuel moisture to within 1 percent moisture
content.
6.7 Anemometer. Device capable of detecting air velocities less
than 0.10 m/sec (20 ft/min), for measuring air velocities near the
test appliance.
6.8 Barometer. Mercury, aneroid or other barometer capable of
measuring atmospheric pressure to within 2.5 mm Hg (0.1 in.
Hg).
6.9 Draft Gauge. Electromanometer or other device for the
determination of flue draft or static pressure readable to within
0.50 Pa (0.002 in. H2O).
6.10 Humidity Gauge. Psychrometer or hygrometer for measuring
room humidity.
6.11 Wood Heater Flue.
6.11.1 Steel flue pipe extending to 2.6 ±0.15 m (8.5 ±0.5 ft)
above the top of the platform scale, and above this level,
insulated solid pack type chimney extending to 4.6 ±0.3 m (15 ±1
ft) above the platform scale, and of the size specified by the wood
heater manufacturer. This applies to both freestanding and insert
type wood heaters.
6.11.2 Other chimney types (e.g., solid pack insulated
pipe) may be used in place of the steel flue pipe if the wood
heater manufacturer's written appliance specifications require such
chimney for home installation (e.g., zero clearance wood
heater inserts). Such alternative chimney or flue pipe must remain
and be sealed with the wood heater following the certification
test.
6.12 Test Facility. The test facility shall meet the following
requirements during testing:
6.12.1 The test facility temperature shall be maintained between
18 and 32 °C (65 and 90 °F) during each test run.
6.12.2 Air velocities within 0.6 m (2 ft) of the test appliance
and exhaust system shall be less than 0.25 m/sec (50 ft/min)
without fire in the unit.
6.12.3 The flue shall discharge into the same space or into a
space freely communicating with the test facility. Any hood or
similar device used to vent combustion products shall not induce a
draft greater than 1.25 Pa (0.005 in. H2O) on the wood heater
measured when the wood heater is not operating.
6.12.4 For test facilities with artificially induced barometric
pressures (e.g., pressurized chambers), the barometric
pressure in the test facility shall not exceed 775 mm Hg (30.5 in.
Hg) during any test run.
7.0 Reagents and Standards
Same as section 6.0 of either Method 5G or Method 5H, with the
addition of the following:
7.1 Test Fuel. The test fuel shall conform to the following
requirements:
7.1.1 Fuel Species. Untreated, air-dried, Douglas fir lumber.
Kiln-dried lumber is not permitted. The lumber shall be certified C
grade (standard) or better Douglas fir by a lumber grader at the
mill of origin as specified in the West Coast Lumber Inspection
Bureau Standard No. 16 (incorporated by reference - see §
60.17).
7.1.2 Fuel Moisture. The test fuel shall have a moisture content
range between 16 to 20 percent on a wet basis (19 to 25 percent dry
basis). Addition of moisture to previously dried wood is not
allowed. It is recommended that the test fuel be stored in a
temperature and humidity-controlled room.
7.1.3 Fuel Temperature. The test fuel shall be at the test
facility temperature of 18 to 32 °C (65 to 90 °F).
7.1.4 Fuel Dimensions. The dimensions of each test fuel piece
shall conform to the nominal measurements of 2 × 4 and 4 × 4
lumber. Each piece of test fuel (not including spacers) shall be of
equal length, except as necessary to meet requirements in section
8.8, and shall closely approximate 5/6 the dimensions of the length
of the usable firebox. The fuel piece dimensions shall be
determined in relation to the appliance's firebox volume according
to guidelines listed below:
7.1.4.1 If the usable firebox volume is less than or equal to
0.043 m 3 (1.5 ft 3), use 2 × 4 lumber.
7.1.4.2 If the usable firebox volume is greater than 0.043 m 3
(1.5 ft 3) and less than or equal to 0.085 m 3 (3.0 ft 3), use 2 ×
4 and 4 × 4 lumber. About half the weight of the test fuel charge
shall be 2 × 4 lumber, and the remainder shall be 4 × 4 lumber.
7.1.4.3 If the usable firebox volume is greater than 0.085 m 3
(3.0 ft 3), use 4 × 4 lumber.
7.2 Test Fuel Spacers. Air-dried, Douglas fir lumber meeting the
requirements outlined in sections 7.1.1 through 7.1.3. The spacers
shall be 130 × 40 × 20 mm (5 × 1.5 × 0.75 in.).
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Test Run Requirements.
8.1.1 Burn Rate Categories. One emission test run is required in
each of the following burn rate categories:
Burn Rate Categories
[Average kg/hr (lb/hr), dry
basis]
Category 1
Category 2
Category 3
Category 4
<0.80
0.80 to 1.25
1.25 to 1.90
Maximum.
(<1.76)
(1.76 to 2.76)
(2.76 to 4.19)
burn rate.
8.1.1.1 Maximum Burn Rate. For Category 4, the wood heater shall
be operated with the primary air supply inlet controls fully open
(or, if thermostatically controlled, the thermostat shall be set at
maximum heat output) during the entire test run, or the maximum
burn rate setting specified by the manufacturer's written
instructions.
8.1.1.2 Other Burn Rate Categories. For burn rates in Categories
1 through 3, the wood heater shall be operated with the primary air
supply inlet control, or other mechanical control device, set at a
predetermined position necessary to obtain the average burn rate
required for the category.
8.1.1.3 Alternative Burn Rates for Burn Rate Categories 1 and
2.
8.1.1.3.1 If a wood heater cannot be operated at a burn rate
below 0.80 kg/hr (1.76 lb/hr), two test runs shall be conducted
with burn rates within Category 2. If a wood heater cannot be
operated at a burn rate below 1.25 kg/hr (2.76 lb/hr), the flue
shall be dampered or the air supply otherwise controlled in order
to achieve two test runs within Category 2.
8.1.1.3.2 Evidence that a wood heater cannot be operated at a
burn rate less than 0.80 kg/hr shall include documentation of two
or more attempts to operate the wood heater in burn rate Category 1
and fuel combustion has stopped, or results of two or more test
runs demonstrating that the burn rates were greater than 0.80 kg/hr
when the air supply controls were adjusted to the lowest possible
position or settings. Stopped fuel combustion is evidenced when an
elapsed time of 30 minutes or more has occurred without a
measurable (<0.05 kg (0.1 lb) or 1.0 percent, whichever is
greater) weight change in the test fuel charge. See also section
8.8.3. Report the evidence and the reasoning used to determine that
a test in burn rate Category 1 cannot be achieved; for example, two
unsuccessful attempts to operate at a burn rate of 0.4 kg/hr are
not sufficient evidence that burn rate Category 1 cannot be
achieved.
Note:
After July 1, 1990, if a wood heater cannot be operated at a
burn rate less than 0.80 kg/hr, at least one test run with an
average burn rate of 1.00 kg/hr or less shall be conducted.
Additionally, if flue dampering must be used to achieve burn rates
below 1.25 kg/hr (or 1.0 kg/hr), results from a test run conducted
at burn rates below 0.90 kg/hr need not be reported or included in
the test run average provided that such results are replaced with
results from a test run meeting the criteria above.
8.2 Catalytic Combustor and Wood Heater Aging. The
catalyst-equipped wood heater or a wood heater of any type shall be
aged before the certification test begins. The aging procedure
shall be conducted and documented by a testing laboratory
accredited according to procedures in § 60.535 of 40 CFR part
60.
8.2.1 Catalyst-equipped Wood Heater. Operate the
catalyst-equipped wood heater using fuel meeting the specifications
outlined in sections 7.1.1 through 7.1.3, or cordwood with a
moisture content between 15 and 25 percent on a wet basis. Operate
the wood heater at a medium burn rate (Category 2 or 3) with a new
catalytic combustor in place and in operation for at least 50
hours. Record and report hourly catalyst exit temperature data
(Section 8.6.2) and the hours of operation.
8.2.2 Non-Catalyst Wood Heater. Operate the wood heater using
the fuel described in section 8.4.1 at a medium burn rate for at
least 10 hours. Record and report the hours of operation.
8.3 Pretest Recordkeeping. Record the test fuel charge
dimensions and weights, and wood heater and catalyst descriptions
as shown in the example in Figure 28-1.
8.4 Wood Heater Installation. Assemble the wood heater appliance
and parts in conformance with the manufacturer's written
installation instructions. Place the wood heater centrally on the
platform scale and connect the wood heater to the flue described in
section 6.11. Clean the flue with an appropriately sized, wire
chimney brush before each certification test.
8.5 Wood Heater Temperature Monitors.
8.5.1 For catalyst-equipped wood heaters, locate a temperature
monitor (optional) about 25 mm (1 in.) upstream of the catalyst at
the centroid of the catalyst face area, and locate a temperature
monitor (mandatory) that will indicate the catalyst exhaust
temperature. This temperature monitor is centrally located within
25 mm (1 in.) downstream at the centroid of catalyst face area.
Record these locations.
8.5.2 Locate wood heater surface temperature monitors at five
locations on the wood heater firebox exterior surface. Position the
temperature monitors centrally on the top surface, on two sidewall
surfaces, and on the bottom and back surfaces. Position the monitor
sensing tip on the firebox exterior surface inside of any heat
shield, air circulation walls, or other wall or shield separated
from the firebox exterior surface. Surface temperature locations
for unusual design shapes (e.g., spherical, etc.) shall be
positioned so that there are four surface temperature monitors in
both the vertical and horizontal planes passing at right angles
through the centroid of the firebox, not including the fuel loading
door (total of five temperature monitors).
8.6 Test Facility Conditions.
8.6.1 Locate the test facility temperature monitor on the
horizontal plane that includes the primary air intake opening for
the wood heater. Locate the temperature monitor 1 to 2 m (3 to 6
ft) from the front of the wood heater in the 90° sector in front of
the wood heater.
8.6.2 Use an anemometer to measure the air velocity. Measure and
record the room air velocity before the pretest ignition period
(Section 8.7) and once immediately following the test run
completion.
8.6.3 Measure and record the test facility's ambient relative
humidity, barometric pressure, and temperature before and after
each test run.
8.6.4 Measure and record the flue draft or static pressure in
the flue at a location no greater than 0.3 m (1 ft) above the flue
connector at the wood heater exhaust during the test run at the
recording intervals (Section 8.8.2).
8.7 Wood Heater Firebox Volume.
8.7.1 Determine the firebox volume using the definitions for
height, width, and length in section 3. Volume adjustments due to
presence of firebrick and other permanent fixtures may be
necessary. Adjust width and length dimensions to extend to the
metal wall of the wood heater above the firebrick or permanent
obstruction if the firebrick or obstruction extending the length of
the side(s) or back wall extends less than one-third of the usable
firebox height. Use the width or length dimensions inside the
firebrick if the firebrick extends more than one-third of the
usable firebox height. If a log retainer or grate is a permanent
fixture and the manufacturer recommends that no fuel be placed
outside the retainer, the area outside of the retainer is excluded
from the firebox volume calculations.
8.7.2 In general, exclude the area above the ash lip if that
area is less than 10 percent of the usable firebox volume.
Otherwise, take into account consumer loading practices. For
instance, if fuel is to be loaded front-to-back, an ash lip may be
considered usable firebox volume.
8.7.3 Include areas adjacent to and above a baffle (up to two
inches above the fuel loading opening) if four inches or more
horizontal space exist between the edge of the baffle and a
vertical obstruction (e.g., sidewalls or air channels).
8.8 Test Fuel Charge.
8.8.1 Prepare the test fuel pieces in accordance with the
specifications outlined in sections 7.1 and 7.2. Determine the test
fuel moisture content with a calibrated electrical resistance meter
or other equivalent performance meter. If necessary, convert fuel
moisture content values from dry basis (%Md) to wet basis (%Mw) in
section 12.2 using Equation 28-1. Determine fuel moisture for each
fuel piece (not including spacers) by averaging at least three
moisture meter readings, one from each of three sides, measured
parallel to the wood grain. Average all the readings for all the
fuel pieces in the test fuel charge. If an electrical resistance
type meter is used, penetration of insulated electrodes shall be
one-fourth the thickness of the test fuel piece or 19 mm (0.75
in.), whichever is greater. Measure the moisture content within a
4-hour period prior to the test run. Determine the fuel temperature
by measuring the temperature of the room where the wood has been
stored for at least 24 hours prior to the moisture
determination.
8.8.2 Attach the spacers to the test fuel pieces with uncoated,
ungalvanized nails or staples as illustrated in Figure 28-2.
Attachment of spacers to the top of the test fuel piece(s) on top
of the test fuel charge is optional.
8.8.3 To avoid stacking difficulties, or when a whole number of
test fuel pieces does not result, all piece lengths shall be
adjusted uniformly to remain within the specified loading density.
The shape of the test fuel crib shall be geometrically similar to
the shape of the firebox volume without resorting to special
angular or round cuts on the individual fuel pieces.
8.8.4 The test fuel loading density shall be 112 ±11.2 kg/m 3 (7
±0.7 lb/ft3) of usable firebox volume on a wet basis.
8.9 Sampling Equipment. Prepare the sampling equipment as
defined by the selected method (i.e., either Method 5G or
Method 5H). Collect one particulate emission sample for each test
run.
8.10 Secondary Air Adjustment Validation.
8.10.1 If design drawings do not show the introduction of
secondary air into a chamber outside the firebox (see “secondary
air supply” under section 3.0, Definitions), conduct a separate
test of the wood heater's secondary air supply. Operate the wood
heater at a burn rate in Category 1 (Section 8.1.1) with the
secondary air supply operated following the manufacturer's written
instructions. Start the secondary air validation test run as
described in section 8.8.1, except no emission sampling is
necessary and burn rate data shall be recorded at 5-minute
intervals.
8.10.2 After the start of the test run, operate the wood heater
with the secondary air supply set as per the manufacturer's
instructions, but with no adjustments to this setting. After 25
percent of the test fuel has been consumed, adjust the secondary
air supply controls to another setting, as per the manufacturer's
instructions. Record the burn rate data (5-minute intervals) for 20
minutes following the air supply adjustment.
8.10.3 Adjust the air supply control(s) to the original
position(s), operate at this condition for at least 20 minutes, and
repeat the air supply adjustment procedure above. Repeat the
procedure three times at equal intervals over the entire burn
period as defined in section 8.8. If the secondary air adjustment
results in a burn rate change of more than an average of 25 percent
between the 20-minute periods before and after the secondary
adjustments, the secondary air supply shall be considered a primary
air supply, and no adjustment to this air supply is allowed during
the test run.
8.10.4 The example sequence below describes a typical secondary
air adjustment validation check. The first cycle begins after at
least 25 percent of the test fuel charge has been consumed.
Cycle 1 Part 1, sec air adjusted to final position - 20 min Part 2,
sec air adjusted to final position - 20 min Part 3, sec air
adjusted to final position - 20 min Cycle 2 Part 1, sec air
adjusted to final position - 20 min Part 2, sec air adjusted to
final position - 20 min Part 3, sec air adjusted to final position
- 20 min Cycle 3 Part 1, sec air adjusted to final position - 20
min Part 2, sec air adjusted to final position - 20 min Part 3, sec
air adjusted to final position - 20 min Note that the cycles may
overlap; that is, Part 3 of Cycle 1 may coincide in part or in
total with Part 1 of Cycle 2. The calculation of the secondary air
percent effect for this example is as follows:
8.11 Pretest Ignition. Build a fire in the wood heater in
accordance with the manufacturer's written instructions.
8.11.1 Pretest Fuel Charge. Crumpled newspaper loaded with
kindling may be used to help ignite the pretest fuel. The pretest
fuel, used to sustain the fire, shall meet the same fuel
requirements prescribed in section 7.1. The pretest fuel charge
shall consist of whole 2 × 4's that are no less than 1/3 the length
of the test fuel pieces. Pieces of 4 × 4 lumber in approximately
the same weight ratio as for the test fuel charge may be added to
the pretest fuel charge.
8.11.2 Wood Heater Operation and Adjustments. Set the air inlet
supply controls at any position that will maintain combustion of
the pretest fuel load. At least one hour before the start of the
test run, set the air supply controls at the approximate positions
necessary to achieve the burn rate desired for the test run.
Adjustment of the air supply controls, fuel addition or
subtractions, and coalbed raking shall be kept to a minimum but are
allowed up to 15 minutes prior to the start of the test run. For
the purposes of this method, coalbed raking is the use of a metal
tool (poker) to stir coals, break burning fuel into smaller pieces,
dislodge fuel pieces from positions of poor combustion, and check
for the condition of uniform charcoalization. Record all
adjustments made to the air supply controls, adjustments to and
additions or subtractions of fuel, and any other changes to wood
heater operations that occur during pretest ignition period. Record
fuel weight data and wood heater temperature measurements at
10-minute intervals during the hour of the pretest ignition period
preceding the start of the test run. During the 15-minute period
prior to the start of the test run, the wood heater loading door
shall not be open more than a total of 1 minute. Coalbed raking is
the only adjustment allowed during this period.
Note:
One purpose of the pretest ignition period is to achieve uniform
charcoalization of the test fuel bed prior to loading the test fuel
charge. Uniform charcoalization is a general condition of the test
fuel bed evidenced by an absence of large pieces of burning wood in
the coal bed and the remaining fuel pieces being brittle enough to
be broken into smaller charcoal pieces with a metal poker.
Manipulations to the fuel bed prior to the start of the test run
should be done to achieve uniform charcoalization while maintaining
the desired burn rate. In addition, some wood heaters (e.g.,
high mass units) may require extended pretest burn time and fuel
additions to reach an initial average surface temperature
sufficient to meet the thermal equilibrium criteria in section
8.3.
8.11.3 The weight of pretest fuel remaining at the start of the
test run is determined as the difference between the weight of the
wood heater with the remaining pretest fuel and the tare weight of
the cleaned, dry wood heater with or without dry ash or sand added
consistent with the manufacturer's instructions and the owner's
manual. The tare weight of the wood heater must be determined with
the wood heater (and ash, if added) in a dry condition.
8.12 Test Run. Complete a test run in each burn rate category,
as follows:
8.12.1 Test Run Start.
8.12.1.1 When the kindling and pretest fuel have been consumed
to leave a fuel weight between 20 and 25 percent of the weight of
the test fuel charge, record the weight of the fuel remaining and
start the test run. Record and report any other criteria, in
addition to those specified in this section, used to determine the
moment of the test run start (e.g., firebox or catalyst
temperature), whether such criteria are specified by the wood
heater manufacturer or the testing laboratory. Record all wood
heater individual surface temperatures, catalyst temperatures, any
initial sampling method measurement values, and begin the
particulate emission sampling. Within 1 minute following the start
of the test run, open the wood heater door, load the test fuel
charge, and record the test fuel charge weight. Recording of
average, rather than individual, surface temperatures is acceptable
for tests conducted in accordance with § 60.533(o)(3)(i) of 40 CFR
part 60.
8.12.1.2 Position the fuel charge so that the spacers are
parallel to the floor of the firebox, with the spacer edges
abutting each other. If loading difficulties result, some fuel
pieces may be placed on edge. If the usable firebox volume is
between 0.043 and 0.085 m 3 (1.5 and 3.0 ft 3), alternate the piece
sizes in vertical stacking layers to the extent possible. For
example, place 2 × 4's on the bottom layer in direct contact with
the coal bed and 4 × 4's on the next layer, etc. (See Figure 28-3).
Position the fuel pieces parallel to each other and parallel to the
longest wall of the firebox to the extent possible within the
specifications in section 8.8.
8.12.1.3 Load the test fuel in appliances having unusual or
unconventional firebox design maintaining air space intervals
between the test fuel pieces and in conformance with the
manufacturer's written instructions. For any appliance that will
not accommodate the loading arrangement specified in the paragraph
above, the test facility personnel shall contact the Administrator
for an alternative loading arrangement.
8.12.1.4 The wood heater door may remain open and the air supply
controls adjusted up to five minutes after the start of the test
run in order to make adjustments to the test fuel charge and to
ensure ignition of the test fuel charge has occurred. Within the
five minutes after the start of the test run, close the wood heater
door and adjust the air supply controls to the position determined
to produce the desired burn rate. No other adjustments to the air
supply controls or the test fuel charge are allowed (except as
specified in sections 8.12.3 and 8.12.4) after the first five
minutes of the test run. Record the length of time the wood heater
door remains open, the adjustments to the air supply controls, and
any other operational adjustments.
8.12.2 Data Recording. Record on a data sheet similar to that
shown in Figure 28-4, at intervals no greater than 10 minutes, fuel
weight data, wood heater individual surface and catalyst
temperature measurements, other wood heater operational data
(e.g., draft), test facility temperature and sampling method
data.
8.12.3 Test Fuel Charge Adjustment. The test fuel charge may be
adjusted (i.e., repositioned) once during a test run if more
than 60 percent of the initial test fuel charge weight has been
consumed and more than 10 minutes have elapsed without a measurable
(<0.05 kg (0.1 lb) or 1.0 percent, whichever is greater) weight
change. The time used to make this adjustment shall be less than 15
seconds.
8.12.4 Air Supply Adjustment. Secondary air supply controls may
be adjusted once during the test run following the manufacturer's
written instructions (see section 8.10). No other air supply
adjustments are allowed during the test run. Recording of wood
heater flue draft during the test run is optional for tests
conducted in accordance with § 60.533(o)(3)(i) of 40 CFR part
60.
8.12.5 Auxiliary Wood Heater Equipment Operation. Heat exchange
blowers sold with the wood heater shall be operated during the test
run following the manufacturer's written instructions. If no
manufacturer's written instructions are available, operate the heat
exchange blower in the “high” position. (Automatically operated
blowers shall be operated as designed.) Shaker grates, by-pass
controls, or other auxiliary equipment may be adjusted only one
time during the test run following the manufacturer's written
instructions.
Record all adjustments on a wood heater operational written
record.
Note:
If the wood heater is sold with a heat exchange blower as an
option, test the wood heater with the heat exchange blower
operating as described in sections 8.1 through 8.12 and report the
results. As an alternative to repeating all test runs without the
heat exchange blower operating, one additional test run may be
without the blower operating as described in section 8.12.5 at a
burn rate in Category 2 (Section 8.1.1). If the emission rate
resulting from this test run without the blower operating is equal
to or less than the emission rate plus 1.0 g/hr (0.0022 lb/hr) for
the test run in burn rate Category 2 with the blower operating, the
wood heater may be considered to have the same average emission
rate with or without the blower operating. Additional test runs
without the blower operating are unnecessary.
8.13 Test Run Completion. Continue emission sampling and wood
heater operation for 2 hours. The test run is completed when the
remaining weight of the test fuel charge is 0.00 kg (0.0 lb). End
the test run when the scale has indicated a test fuel charge weight
of 0.00 kg (0.0 lb) or less for 30 seconds. At the end of the test
run, stop the particulate sampling, and record the final fuel
weight, the run time, and all final measurement values.
8.14 Wood Heater Thermal Equilibrium. The average of the wood
heater surface temperatures at the end of the test run shall agree
with the average surface temperature at the start of the test run
to within 70 °C (126 °F).
8.15 Consecutive Test Runs. Test runs on a wood heater may be
conducted consecutively provided that a minimum one-hour interval
occurs between test runs.
8.16 Additional Test Runs. The testing laboratory may conduct
more than one test run in each of the burn rate categories
specified in section 8.1.1. If more than one test run is conducted
at a specified burn rate, the results from at least two-thirds of
the test runs in that burn rate category shall be used in
calculating the weighted average emission rate (see section 12.2).
The measurement data and results of all test runs shall be reported
regardless of which values are used in calculating the weighted
average emission rate (see note in section 8.1).
9.0 Quality Control
Same as section 9.0 of either Method 5G or Method 5H.
10.0 Calibration and Standardizations
Same as section 10.0 of either Method 5G or Method 5H, with the
addition of the following:
10.1 Platform Scale. Perform a multi-point calibration (at least
five points spanning the operational range) of the platform scale
before its initial use. The scale manufacturer's calibration
results are sufficient for this purpose. Before each certification
test, audit the scale with the wood heater in place by weighing at
least one calibration weight (Class F) that corresponds to between
20 percent and 80 percent of the expected test fuel charge weight.
If the scale cannot reproduce the value of the calibration weight
within 0.05 kg (0.1 lb) or 1 percent of the expected test fuel
charge weight, whichever is greater, recalibrate the scale before
use with at least five calibration weights spanning the operational
range of the scale.
10.2 Balance (optional). Calibrate as described in section
10.1.
10.3 Temperature Monitor. Calibrate as in Method 2, section 4.3,
before the first certification test and semiannually
thereafter.
10.4 Moisture Meter. Calibrate as per the manufacturer's
instructions before each certification test.
10.5 Anemometer. Calibrate the anemometer as specified by the
manufacturer's instructions before the first certification test and
semiannually thereafter.
10.6 Barometer. Calibrate against a mercury barometer before the
first certification test and semiannually thereafter.
10.7 Draft Gauge. Calibrate as per the manufacturer's
instructions; a liquid manometer does not require calibration.
10.8 Humidity Gauge. Calibrate as per the manufacturer's
instructions before the first certification test and semiannually
thereafter.
11.0 Analytical Procedures
Same as section 11.0 of either Method 5G or Method 5H.
12.0 Data Analysis and Calculations
Same as section 12.0 of either Method 5G or Method 5H, with the
addition of the following:
12.1 Nomenclature.
BR = Dry wood burn rate, kg/hr (lb/hr) Ei = Emission rate for test
run, i, from Method 5G or 5H, g/hr (lb/hr) Ew = Weighted average
emission rate, g/hr (lb/hr) ki = Test run weighting factor = Pi + 1
− Pi−1 %Md = Fuel moisture content, dry basis, percent. %Mw =
Average moisture in test fuel charge, wet basis, percent. n = Total
number of test runs. Pi = Probability for burn rate during test
run, i, obtained from Table 28-1. Use linear interpolation to
determine probability values for burn rates between those listed on
the table. Wwd = Total mass of wood burned during the test run, kg
(lb).
12.2 Wet Basis Fuel Moisture Content.
12.3 Weighted Average Emission Rate. Calculate the weighted
average emission rate (Ew) using Equation 28-1:
Note:
Po always equals 0, P(n + 1) always equals 1, P1 corresponds to
the probability of the lowest recorded burn rate, P2 corresponds to
the probability of the next lowest burn rate, etc. An example
calculation is in section 12.3.1.
12.3.1 Example Calculation of Weighted Average Emission
Rate.
Burn rate category
Test
No.
Burn rate
(Dry-kg/hr)
Emissions
(g/hr)
1
1
0.65
5.0
2
1
2
0.85
6.7
2
3
0.90
4.7
2
4
1.00
5.3
3
5
1.45
3.8
4
6
2.00
5.1
1 As permitted in section 6.6,
this test run may be omitted from the calculation of the weighted
average emission rate because three runs were conducted for this
burn rate category.
Test No.
Burn rate
Pi
Ei
Ki
0
0.000
1
0.65
0.121
5.0
0.300
2
0.90
0.300
4.7
0.259
3
1.00
0.380
5.3
0.422
4
1.45
0.722
3.8
0.532
5
2.00
0.912
5.1
0.278
6
1.000
K1 = P2 − P0 = 0.300 − 0 = 0.300
K2 = P3 − P1 = 0.381 − 0.121 = 0.259
K3 = P4 − P2 = 0.722 − 0.300 = 0.422
K4 = P5 − P3 = 0.912 − 0.380 = 0.532
K5 = P6 − P4 = 1.000 − 0.722 = 0.278
Weighted Average Emission Rate, Ew, Calculation
12.4 Average Wood Heater Surface Temperatures. Calculate the
average of the wood heater surface temperatures for the start of
the test run (Section 8.12.1) and for the test run completion
(Section 8.13). If the two average temperatures do not agree within
70 °C (125 °F), report the test run results, but do not include the
test run results in the test average. Replace such test run results
with results from another test run in the same burn rate
category.
12.5 Burn Rate. Calculate the burn rate (BR) using Equation
28-3:
12.6 Reporting Criteria. Submit both raw and reduced test data
for wood heater tests.
12.6.1 Suggested Test Report Format.
12.6.1.1 Introduction.
12.6.1.1.1 Purpose of test-certification, audit, efficiency,
research and development.
12.6.1.1.2 Wood heater identification-manufacturer, model
number, catalytic/noncatalytic, options.
12.6.1.1.4 Test information-date wood heater received, date of
tests, sampling methods used, number of test runs.
12.6.1.2 Summary and Discussion of Results
12.6.1.2.1 Table of results (in order of increasing burn
rate)-test run number, burn rate, particulate emission rate,
efficiency (if determined), averages (indicate which test runs are
used).
12.6.1.2.2 Summary of other data-test facility conditions,
surface temperature averages, catalyst temperature averages,
pretest fuel weights, test fuel charge weights, run times.
12.6.1.2.3 Discussion-Burn rate categories achieved, test run
result selection, specific test run problems and solutions.
12.6.1.3 Process Description.
12.6.1.3.1 Wood heater dimensions-volume, height, width, lengths
(or other linear dimensions), weight, volume adjustments.
12.6.1.3.2 Firebox configuration-air supply locations and
operation, air supply introduction location, refractory location
and dimensions, catalyst location, baffle and by-pass location and
operation (include line drawings or photographs).
12.6.1.3.3 Process operation during test-air supply settings and
adjustments, fuel bed adjustments, draft.
12.6.1.3.4 Test fuel-test fuel properties (moisture and
temperature), test fuel crib description (include line drawing or
photograph), test fuel loading density.
12.6.1.4 Sampling Locations.
12.6.1.4.1 Describe sampling location relative to wood heater.
Include drawing or photograph.
12.6.1.5 Sampling and Analytical Procedures
12.6.1.5.1 Sampling methods-brief reference to operational and
sampling procedures and optional and alternative procedures
used.
12.6.1.5.2 Analytical methods-brief description of sample
recovery and analysis procedures.
12.6.1.6 Quality Control and Assurance Procedures and
Results
12.6.1.6.1 Calibration procedures and results-certification
procedures, sampling and analysis procedures.
12.6.1.6.2 Test method quality control procedures-leak-checks,
volume meter checks, stratification (velocity) checks,
proportionality results.
12.6.1.7 Appendices
12.6.1.7.1 Results and Example Calculations. Complete summary
tables and accompanying examples of all calculations.
12.6.1.7.2 Raw Data. Copies of all uncorrected data sheets for
sampling measurements, temperature records and sample recovery
data. Copies of all pretest burn rate and wood heater temperature
data.
12.6.1.7.3 Sampling and Analytical Procedures. Detailed
description of procedures followed by laboratory personnel in
conducting the certification test, emphasizing particular parts of
the procedures differing from the methods (e.g., approved
alternatives).
12.6.1.7.4 Calibration Results. Summary of all calibrations,
checks, and audits pertinent to certification test results with
dates.
12.6.1.7.5 Participants. Test personnel, manufacturer
representatives, and regulatory observers.
12.6.1.7.6 Sampling and Operation Records. Copies of uncorrected
records of activities not included on raw data sheets (e.g.,
wood heater door open times and durations).
12.6.1.7.7 Additional Information. Wood heater manufacturer's
written instructions for operation during the certification
test.
12.6.2.1 Wood Heater Identification. Report wood heater
identification information. An example data form is shown in Figure
28-4.
12.6.2.2 Test Facility Information. Report test facility
temperature, air velocity, and humidity information. An example
data form is shown on Figure 28-4.
12.6.2.3 Test Equipment Calibration and Audit Information.
Report calibration and audit results for the platform scale, test
fuel balance, test fuel moisture meter, and sampling equipment
including volume metering systems and gaseous analyzers.
12.6.2.4 Pretest Procedure Description. Report all pretest
procedures including pretest fuel weight, burn rates, wood heater
temperatures, and air supply settings. An example data form is
shown on Figure 28-4.
12.6.2.5 Particulate Emission Data. Report a summary of test
results for all test runs and the weighted average emission rate.
Submit copies of all data sheets and other records collected during
the testing. Submit examples of all calculations.
16.1 Pellet Burning Heaters. Certification testing requirements
and procedures for pellet burning wood heaters are identical to
those for other wood heaters, with the following exceptions:
16.1.1 Test Fuel Properties. The test fuel shall be all wood
pellets with a moisture content no greater than 20 percent on a wet
basis (25 percent on a dry basis). Determine the wood moisture
content with either ASTM D 2016-74 or 83, (Method A), ASTM D
4444-92, or ASTM D 4442-84 or 92 (all noted ASTM standards are
incorporated by reference - see § 60.17).
16.1.2 Test Fuel Charge Specifications. The test fuel charge
size shall be as per the manufacturer's written instructions for
maintaining the desired burn rate.
16.1.3 Wood Heater Firebox Volume. The firebox volume need not
be measured or determined for establishing the test fuel charge
size. The firebox dimensions and other heater specifications needed
to identify the heater for certification purposes shall be
reported.
16.1.4 Heater Installation. Arrange the heater with the fuel
supply hopper on the platform scale as described in section
8.6.1.
16.1.5 Pretest Ignition. Start a fire in the heater as directed
by the manufacturer's written instructions, and adjust the heater
controls to achieve the desired burn rate. Operate the heater at
the desired burn rate for at least 1 hour before the start of the
test run.
16.1.6 Test Run. Complete a test run in each burn rate category
as follows:
16.1.6.1 Test Run Start. When the wood heater has operated for
at least 1 hour at the desired burn rate, add fuel to the supply
hopper as necessary to complete the test run, record the weight of
the fuel in the supply hopper (the wood heater weight), and start
the test run. Add no additional fuel to the hopper during the test
run.
Record all the wood heater surface temperatures, the initial
sampling method measurement values, the time at the start of the
test, and begin the emission sampling. Make no adjustments to the
wood heater air supply or wood supply rate during the test run.
16.1.6.2 Data Recording. Record the fuel (wood heater) weight
data, wood heater temperature and operational data, and emission
sampling data as described in section 8.12.2.
16.1.6.3 Test Run Completion. Continue emission sampling and
wood heater operation for 2 hours. At the end of the test run, stop
the particulate sampling, and record the final fuel weight, the run
time, and all final measurement values, including all wood heater
individual surface temperatures.
16.1.7 Calculations. Determine the burn rate using the
difference between the initial and final fuel (wood heater) weights
and the procedures described in section 12.4. Complete the other
calculations as described in section 12.0.
17.0 References
Same as Method 5G, with the addition of the following:
1. Radian Corporation. OMNI Environmental Services, Inc.,
Cumulative Probability for a Given Burn Rate Based on Data
Generated in the CONEG and BPA Studies. Package of materials
submitted to the Fifth Session of the Regulatory Negotiation
Committee, July 16-17, 1986.
18.0 Tables, Diagrams, Flowcharts, and Validation Data
Table 28-1 - Burn Rate Weighted
Probabilities for Calculating Weighted Average Emission Rates
Burn rate
(kg/hr-dry)
Cumulative
probability (P)
Burn rate
(kg/hr-dry)
Cumulative
probability (P)
Burn rate
(kg/hr-dry)
Cumulative
probability (P)
0.00
0.000
1.70
0.840
3.40
0.989
0.05
0.002
1.75
0.857
3.45
0.989
0.10
0.007
1.80
0.875
3.50
0.990
0.15
0.012
1.85
0.882
3.55
0.991
0.20
0.016
1.90
0.895
3.60
0.991
0.25
0.021
1.95
0.906
3.65
0.992
0.30
0.028
2.00
0.912
3.70
0.992
0.35
0.033
2.05
0.920
3.75
0.992
0.40
0.041
2.10
0.925
3.80
0.993
0.45
0.054
2.15
0.932
3.85
0.994
0.50
0.065
2.20
0.936
3.90
0.994
0.55
0.086
2.25
0.940
3.95
0.994
0.60
0.100
2.30
0.945
4.00
0.994
0.65
0.121
2.35
0.951
4.05
0.995
0.70
0.150
2.40
0.956
4.10
0.995
0.75
0.185
2.45
0.959
4.15
0.995
0.80
0.220
2.50
0.964
4.20
0.995
0.85
0.254
2.55
0.968
4.25
0.995
0.90
0.300
2.60
0.972
4.30
0.996
0.95
0.328
2.65
0.975
4.35
0.996
1.00
0.380
2.70
0.977
4.40
0.996
1.05
0.407
2.75
0.979
4.45
0.996
1.10
0.460
2.80
0.980
4.50
0.996
1.15
0.490
2.85
0.981
4.55
0.996
1.20
0.550
2.90
0.982
4.60
0.996
1.25
0.572
2.95
0.984
4.65
0.996
1.30
0.620
3.00
0.984
4.70
0.996
1.35
0.654
3.05
0.985
4.75
0.997
1.40
0.695
3.10
0.986
4.80
0.997
1.45
0.722
3.15
0.987
4.85
0.997
1.50
0.750
3.20
0.987
4.90
0.997
1.55
0.779
3.25
0.988
4.95
0.997
1.60
0.800
3.30
0.988
≥5.00
1.000
1.65
0.825
3.35
0.989
Method 28A -
Measurement of Air- to-Fuel Ratio and Minimum Achievable Burn Rates
for Wood-Fired Appliances Note:
This method does not include all or the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should also have a thorough knowledge of at least the
following additional test methods: Method 3, Method 3A, Method 5H,
Method 6C, and Method 28.
1.0 Scope and Application
1.1 Analyte. Particulate matter (PM). No CAS number
assigned.
1.2 Applicability. This method is applicable for the measurement
of air-to-fuel ratios and minimum achievable burn rates, for
determining whether a wood-fired appliance is an affected facility,
as specified in 40 CFR 60.530.
1.3 Data Quality Objectives. Adherence to the requirements of
this method will enhance the quality of the data obtained from air
pollutant sampling methods.
2.0 Summary of Method
2.1 A gas sample is extracted from a location in the stack of a
wood-fired appliance while the appliance is operating at a
prescribed set of conditions. The gas sample is analyzed for carbon
dioxide (CO2), oxygen (O2), and carbon monoxide (CO). These stack
gas components are measured for determining the dry molecular
weight of the exhaust gas. Total moles of exhaust gas are
determined stoichiometrically. Air-to-fuel ratio is determined by
relating the mass of dry combustion air to the mass of dry fuel
consumed.
3.0 Definitions
Same as Method 28, section 3.0, with the addition of the
following:
3.1 Air-to-fuel ratio means the ratio of the mass of dry
combustion air introduced into the firebox to the mass of dry fuel
consumed (grams of dry air per gram of dry wood burned).
4.0 Interferences [Reserved] 5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
6.0 Equipment and Supplies
6.1 Test Facility. Insulated Solid Pack Chimney, Platform Scale
and Monitor, Test Facility Temperature Monitor, Balance, Moisture
Meter, Anemometer, Barometer, Draft Gauge, Humidity Gauge, Wood
Heater Flue, and Test Facility. Same as Method 28, sections 6.1,
6.2, and 6.4 to 6.12, respectively.
6.2 Sampling System. Probe, Condenser, Valve, Pump, Rate Meter,
Flexible Bag, Pressure Gauge, and Vacuum Gauge. Same as Method 3,
sections 6.2.1 to 6.2.8, respectively. Alternatively, the sampling
system described in Method 5H, section 6.1 may be used.
6.3 Exhaust Gas Analysis. Use one or both of the following:
6.3.1 Orsat Analyzer. Same as Method 3, section 6.1.3
6.3.2 Instrumental Analyzers. Same as Method 5H, sections
6.1.3.4 and 6.1.3.5, for CO2 and CO analyzers, except use a CO
analyzer with a range of 0 to 5 percent and use a CO2 analyzer with
a range of 0 to 5 percent. Use an O2 analyzer capable of providing
a measure of O2 in the range of 0 to 25 percent by volume at least
once every 10 minutes.
7.0 Reagents and Standards
7.1 Test Fuel and Test Fuel Spacers. Same as Method 28, sections
7.1 and 7.2, respectively.
7.2 Cylinder Gases. For each of the three analyzers, use the
same concentration as specified in sections 7.2.1, 7.2.2, and 7.2.3
of Method 6C.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Wood Heater Air Supply Adjustments.
8.1.1 This section describes how dampers are to be set or
adjusted and air inlet ports closed or sealed during Method 28A
tests. The specifications in this section are intended to ensure
that affected facility determinations are made on the facility
configurations that could reasonably be expected to be employed by
the user. They are also intended to prevent circumvention of the
standard through the addition of an air port that would often be
blocked off in actual use. These specifications are based on the
assumption that consumers will remove such items as dampers or
other closure mechanism stops if this can be done readily with
household tools; that consumers will block air inlet passages not
visible during normal operation of the appliance using aluminum
tape or parts generally available at retail stores; and that
consumers will cap off any threaded or flanged air inlets. They
also assume that air leakage around glass doors, sheet metal joints
or through inlet grilles visible during normal operation of the
appliance would not be further blocked or taped off by a
consumer.
8.1.2 It is not the intention of this section to cause an
appliance that is clearly designed, intended, and, in most normal
installations, used as a fireplace to be converted into a wood
heater for purposes of applicability testing. Such a fireplace
would be identifiable by such features as large or multiple glass
doors or panels that are not gasketed, relatively unrestricted air
inlets intended, in large part, to limit smoking and fogging of
glass surfaces, and other aesthetic features not normally included
in wood heaters.
8.1.3 Adjustable Air Supply Mechanisms. Any commercially
available flue damper, other adjustment mechanism or other air
inlet port that is designed, intended or otherwise reasonably
expected to be adjusted or closed by consumers, installers, or
dealers and which could restrict air into the firebox shall be set
so as to achieve minimum air into the firebox (i.e., closed
off or set in the most closed position).
8.1.3.1 Flue dampers, mechanisms and air inlet ports which could
reasonably be expected to be adjusted or closed would include:
8.1.3.1.1 All internal or externally adjustable mechanisms
(including adjustments that affect the tightness of door fittings)
that are accessible either before and/or after installation.
8.1.3.1.2 All mechanisms, other inlet ports, or inlet port stops
that are identified in the owner's manual or in any dealer
literature as being adjustable or alterable. For example, an inlet
port that could be used to provide access to an outside air duct
but which is identified as being closable through use of additional
materials whether or not they are supplied with the facility.
8.1.3.1.3 Any combustion air inlet port or commercially
available flue damper or mechanism stop, which would readily lend
itself to closure by consumers who are handy with household tools
by the removal of parts or the addition of parts generally
available at retail stores (e.g., addition of a pipe cap or
plug, addition of a small metal plate to an inlet hole on a
nondecorative sheet metal surface, or removal of riveted or screwed
damper stops).
8.1.3.1.4 Any flue damper, other adjustment mechanisms or other
air inlet ports that are found and documented in several
(e.g., a number sufficient to reasonably conclude that the
practice is not unique or uncommon) actual installations as having
been adjusted to a more closed position, or closed by consumers,
installers, or dealers.
8.1.4 Air Supply Adjustments During Test. The test shall be
performed with all air inlets identified under this section in the
closed or most closed position or in the configuration which
otherwise achieves the lowest air inlet (i.e., greatest
blockage).
Note:
For the purposes of this section, air flow shall not be
minimized beyond the point necessary to maintain combustion or
beyond the point that forces smoke into the room.
8.1.5 Notwithstanding section 8.1.1, any flue damper, adjustment
mechanism, or air inlet port (whether or not equipped with flue
dampers or adjusting mechanisms) that is visible during normal
operation of the appliance and which could not reasonably be closed
further or blocked except through means that would significantly
degrade the aesthetics of the facility (e.g., through use of
duct tape) will not be closed further or blocked.
8.2 Sampling System.
8.2.1 Sampling Location. Same as Method 5H, section 8.1.2.
8.2.2 Sampling System Set Up. Set up the sampling equipment as
described in Method 3, section 8.1.
8.3 Wood Heater Installation, Test Facility Conditions, Wood
Heater Firebox Volume, and Test Fuel Charge. Same as Method 28,
sections 8.4 and 8.6 to 8.8, respectively.
8.4 Pretest Ignition. Same as Method 28, section 8.11. Set the
wood heater air supply settings to achieve a burn rate in Category
1 or the lowest achievable burn rate (see section 8.1).
8.5 Test Run. Same as Method 28, section 8.12. Begin sample
collection at the start of the test run as defined in Method 28,
section 8.12.1.
8.5.1 Gas Analysis.
8.5.1.1 If Method 3 is used, collect a minimum of two bag
samples simultaneously at a constant sampling rate for the duration
of the test run. A minimum sample volume of 30 liters (1.1 ft 3)
per bag is recommended.
8.5.1.2 If instrumental gas concentration measurement procedures
are used, conduct the gas measurement system performance tests,
analyzer calibration, and analyzer calibration error check outlined
in Method 6C, sections 8.2.3, 8.2.4, 8.5, and 10.0, respectively.
Sample at a constant rate for the duration of the test run.
8.5.2 Data Recording. Record wood heater operational data, test
facility temperature, sample train flow rate, and fuel weight data
at intervals of no greater than 10 minutes.
8.5.3 Test Run Completion. Same as Method 28, section 8.13.
9.0 Quality Control
9.1 Data Validation. The following quality control procedure is
suggested to provide a check on the quality of the data.
9.1.1 Calculate a fuel factor, Fo, using Equation 28A-1 in
section 12.2.
9.1.2 If CO is present in quantities measurable by this method,
adjust the O2 and CO2 values before performing the calculation for
Fo as shown in section 12.3 and 12.4.
9.1.3 Compare the calculated Fo factor with the expected Fo
range for wood (1.000-1.120). Calculated Fo values beyond this
acceptable range should be investigated before accepting the test
results. For example, the strength of the solutions in the gas
analyzer and the analyzing technique should be checked by sampling
and analyzing a known concentration, such as air. If no detectable
or correctable measurement error can be identified, the test should
be repeated. Alternatively, determine a range of air-to-fuel ratio
results that could include the correct value by using an Fo value
of 1.05 and calculating a potential range of CO2 and O2 values.
Acceptance of such results will be based on whether the calculated
range includes the exemption limit and the judgment of the
Administrator.
9.2 Method 3 Analyses. Compare the results of the analyses of
the two bag samples. If all the gas components (O2, CO, and CO2)
values for the two analyses agree within 0.5 percent (e.g.,
6.0 percent O2 for bag 1 and 6.5 percent O2 for bag 2, agree within
0.5 percent), the results of the bag analyses may be averaged for
the calculations in section 12. If the analysis results do not
agree within 0.5 percent for each component, calculate the
air-to-fuel ratio using both sets of analyses and report the
results.
10.0 Calibration and Standardization [Reserved] 11.0 Analytical
Procedures
11.1 Method 3 Integrated Bag Samples. Within 4 hours after the
sample collection, analyze each bag sample for percent CO2, O2, and
CO using an Orsat analyzer as described in Method 3, section
11.0.
11.2 Instrumental Analyzers. Average the percent CO2, CO, and O2
values for the test run.
12.0 Data Analyses and Calculations
Carry out calculations, retaining at least one extra significant
figure beyond that of the acquired data. Round off figure after the
final calculation. Other forms of the equations may be used as long
as they give equivalent results.
12.1 Nomenclature.
Md = Dry molecular weight, g/g-mole (lb/lb-mole). NT = Total
gram-moles of dry exhaust gas per kg of wood burned (lb-moles/lb).
%CO2 = Percent CO2 by volume (dry basis). %CO = Percent CO by
volume (dry basis). %N2 = Percent N2 by volume (dry basis). %O2 =
Percent O2 by volume (dry basis). YHC = Assumed mole fraction of HC
(dry as CH4) = 0.0088 for catalytic wood heaters; = 0.0132 for
noncatalytic wood heaters. = 0.0080 for pellet-fired wood heaters.
YCO = Measured mole fraction of CO (e.g., 1 percent CO = .01
mole fraction), g/g-mole (lb/lb-mole). YCO2 = Measured mole
fraction of COCO2 (e.g., 10 percent CO2 = .10 mole
fraction), g/g-mole (lb/lb-mole). 0.280 = Molecular weight of N2 or
CO, divided by 100. 0.320 = Molecular weight of O2 divided by 100.
0.440 = Molecular weight of CO2 divided by 100. 20.9 = Percent O2
by volume in ambient air. 42.5 = Gram-moles of carbon in 1 kg of
dry wood assuming 51 percent carbon by weight dry basis (.0425
lb/lb-mole). 510 = Grams of carbon in exhaust gas per kg of wood
burned. 1,000 = Grams in 1 kg.
12.2 Fuel Factor. Use Equation 28A-1 to calculate the fuel
factor.
12. 3 Adjusted %CO2. Use Equation 28A-2 to adjust CO2 values if
measurable CO is present.
12.4 Adjusted %O2. Use Equation 28A-3 to adjust O2 value if
measurable CO is present.
12.5 Dry Molecular Weight. Use Equation 28A-4 to calculate the
dry molecular weight of the stack gas.
Note:
The above equation does not consider argon in air (about 0.9
percent, molecular weight of 39.9). A negative error of about 0.4
percent is introduced. Argon may be included in the analysis using
procedures subject to approval of the Administrator.
12.6 Dry Moles of Exhaust Gas. Use Equation 28A-5 to calculate
the total moles of dry exhaust gas produced per kilogram of dry
wood burned.
12.7 Air-to-Fuel Ratio. Use Equation 28A-6 to calculate the
air-to-fuel ratio on a dry mass basis.
12.8 Burn Rate. Calculate the fuel burn rate as in Method 28,
section 12.4.
Same as section 16.0 of Method 3 and section 17 of Method
5G.
17.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
Test Method 28R for Certification and Auditing of Wood Heaters 1.0
Scope and Application
1.1 This test method applies to certification and auditing of
wood-fired room heaters and fireplace inserts.
1.2 The test method covers the fueling and operating protocol
for measuring particulate emissions, as well as determining burn
rates, heat output and efficiency.
1.3 Particulate emissions are measured by the dilution tunnel
method as specified in ASTM E2515-11 Standard Test Method for
Determination of Particulate Matter Emissions Collected in a
Dilution Tunnel (IBR, see § 60.17). Upon request, four-inch
filters may be used. Upon request, Teflon membrane filters or
Teflon-coated glass fiber filters may be used.
2.0 Procedures
2.1 This method incorporates the provisions of ASTM E2780-10
(IBR, see § 60.17) except as follows:
2.1.1 The burn rate categories, low burn rate requirement, and
weightings in Method 28 shall be used.
2.1.2 The startup procedures shall be the same as in Method
28.
2.1.3 Manufacturers shall not specify a smaller volume of the
firebox for testing than the full usable firebox.
2.1.4 Prior to testing, the heater must be operated for a
minimum of 50 hours using a medium burn rate. The conditioning may
be at the manufacturer's facility prior to the certification test.
If the conditioning is at the certification test laboratory, the
pre-burn for the first test can be included as part of the
conditioning requirement.
2.2 Manufacturers may use ASTM E871-82 (reapproved 2013) (IBR,
see § 60.17) as an alternative to the procedures in Method 5H or
Method 28 for determining total weight basis moisture in the
analysis sample of particulate wood fuel.
Test Method 28WHH for Measurement of Particulate Emissions and
Heating Efficiency of Wood-Fired Hydronic Heating Appliances 1.0
Scope and Application
1.1 This test method applies to wood-fired hydronic heating
appliances. The units typically transfer heat through circulation
of a liquid heat exchange media such as water or a water-antifreeze
mixture.
1.2 The test method measures particulate emissions and delivered
heating efficiency at specified heat output rates based on the
appliance's rated heating capacity.
1.3 Particulate emissions are measured by the dilution tunnel
method as specified in ASTM E2515-11 Standard Test Method for
Determination of Particulate Matter Emissions Collected in a
Dilution Tunnel (IBR, see § 60.17). Upon request, four-inch
filters may be used. Upon request, Teflon membrane filters or
Teflon-coated glass fiber filters may be used. Delivered efficiency
is measured by determining the heat output through measurement of
the flow rate and temperature change of water circulated through a
heat exchanger external to the appliance and determining the input
from the mass of dry wood fuel and its higher heating value.
Delivered efficiency does not attempt to account for pipeline
loss.
1.4 Products covered by this test method include both
pressurized and non-pressurized heating appliances intended to be
fired with wood. These products are wood-fired hydronic heating
appliances that the manufacturer specifies for indoor or outdoor
installation. They are often connected to a heat exchanger by
insulated pipes and normally include a pump to circulate heated
liquid. They are used to heat structures such as homes, barns and
greenhouses and can heat domestic hot water, spas or swimming
pools.
1.5 Distinguishing features of products covered by this standard
include:
1.5.1 Manufacturer specifies for indoor or outdoor
installation.
1.5.2 A firebox with an access door for hand loading of
fuel.
1.5.3 Typically, an aquastat that controls combustion air supply
to maintain the liquid in the appliance within a predetermined
temperature range provided sufficient fuel is available in the
firebox.
1.5.4 A chimney or vent that exhausts combustion products from
the appliance.
1.6 The values stated are to be regarded as the standard whether
in I-P or SI units. The values given in parentheses are for
information only.
2.0 Summary of Method and References
2.1 Particulate matter emissions are measured from a wood-fired
hydronic heating appliance burning a prepared test fuel crib in a
test facility maintained at a set of prescribed conditions.
Procedures for determining burn rates, and particulate emissions
rates and for reducing data are provided.
2.2 Referenced Documents
2.2.1 EPA Standards
2.2.1.1 Method 28 Certification and Auditing of Wood Heaters
2.2.2 Other Standards
2.2.2.1 ASTM E2515-11 - Standard Test Method for
Determination of Particulate Matter Emissions Collected in a
Dilution Tunnel (IBR, see § 60.17).
2.2.2.2 CSA-B415.1-10 Performance Testing of
Solid-Fuel-Burning Heating Appliances (IBR, see § 60.17).
3.0 Terminology
3.1 Definitions.
3.1.1 Hydronic Heating - A heating system in which a heat source
supplies energy to a liquid heat exchange media such as water that
is circulated to a heating load and returned to the heat source
through pipes.
3.1.2 Aquastat - A control device that opens or closes a circuit
to control the rate of fuel consumption in response to the
temperature of the heating media in the heating appliance.
3.1.3 Delivered Efficiency - The percentage of heat available in
a test fuel charge that is delivered to a simulated heating load as
specified in this test method.
3.1.4 Manufacturer's Rated Heat Output Capacity - The value in
Btu/hr (MJ/hr) that the manufacturer specifies that a particular
model of hydronic heating appliance is capable of supplying at its
design capacity as verified by testing, in accordance with Section
13.
3.1.5 Burn Rate - The rate at which test fuel is consumed in an
appliance. Measured in pounds (lbs) or kilograms of wood (dry
basis) per hour (lb/hr or kg/hr).
3.1.6 Firebox - The chamber in the appliance in which the test
fuel charge is placed and combusted.
3.1.7 Test Fuel Charge - The collection of test fuel layers
placed in the appliance at the start of the emission test run.
3.1.8 Test Fuel Layer - Horizontal arrangement of test fuel
units.
3.1.9 Test Fuel Unit - One or more test fuel pieces with 3/4
inch (19 mm) spacers attached to the bottom and to one side. If
composed of multiple test fuel pieces, the bottom spacer may be one
continuous piece.
3.1.10 Test Fuel Piece - A single 4 × 4 (4 ±0.25 inches by 4
±0.25 inches) [100 ±6 mm by 100 ±6 mm] white or red oak wood piece
cut to the length required.
3.1.11 Test Run - An individual emission test that encompasses
the time required to consume the mass of the test fuel charge.
3.1.12 Overall Efficiency (SLM) - The efficiency for each test
run as determined using the CSA B415.1-10 (IBR, see § 60.17) stack
loss method.
3.1.13 Thermopile - A device consisting of a number of
thermocouples connected in series, used for measuring differential
temperature.
4.0 Summary of Test Method
4.1 Dilution Tunnel. Emissions are determined using the
“dilution tunnel” method specified in ASTM E2515-11 Standard
Test Method for Determination of Particulate Matter Emissions
Collected in a Dilution Tunnel (IBR, see § 60.17). The flow
rate in the dilution tunnel is maintained at a constant level
throughout the test cycle and accurately measured. Samples of the
dilution tunnel flow stream are extracted at a constant flow rate
and drawn through high efficiency filters. The filters are dried
and weighed before and after the test to determine the emissions
catch and this value is multiplied by the ratio of tunnel flow to
filter flow to determine the total particulate emissions produced
in the test cycle.
4.2 Efficiency. The efficiency test procedure takes advantage of
the fact that this type of appliance delivers heat through
circulation of the heated liquid (water) from the appliance to a
remote heat exchanger and back to the appliance. Measurements of
the water temperature difference as it enters and exits the heat
exchanger along with the measured flow rate allow for an accurate
determination of the useful heat output of the appliance. The input
is determined by weight of the test fuel charge, adjusted for
moisture content, multiplied by the higher heating value.
Additional measurements of the appliance weight and temperature at
the beginning and end of a test cycle are used to correct for heat
stored in the appliance. Overall efficiency (SLM) is determined
using the CSA B415.1-10 (IBR, see § 60.17) stack loss method for
data quality assurance purposes.
4.3 Operation. Appliance operation is conducted on a hot-to-hot
test cycle meaning that the appliance is brought to operating
temperature and a coal bed is established prior to the addition of
the test fuel charge and measurements are made for each test fuel
charge cycle. The measurements are made under constant heat draw
conditions within predetermined ranges. No attempt is made to
modulate the heat demand to simulate an indoor thermostat cycling
on and off in response to changes in the indoor environment. Four
test categories are used. These are:
4.3.1 Category I: A heat output of 15 percent or less of
manufacturer's rated heat output capacity.
4.3.2 Category II: A heat output of 16 percent to 24 percent of
manufacturer's rated heat output capacity.
4.3.3 Category III: A heat output of 25 percent to 50 percent of
manufacturer's rated heat output capacity.
5.1 The measurement of particulate matter emission rates is an
important test method widely used in the practice of air pollution
control.
5.1.1 These measurements, when approved by state or federal
agencies, are often required for the purpose of determining
compliance with regulations and statutes.
5.1.2 The measurements made before and after design
modifications are necessary to demonstrate the effectiveness of
design changes in reducing emissions and make this standard an
important tool in manufacturers' research and development
programs.
5.2 Measurement of heating efficiency provides a uniform basis
for comparison of product performance that is useful to the
consumer. It is also required to relate emissions produced to the
useful heat production.
5.3 This is a laboratory method and is not intended to be fully
representative of all actual field use. It is recognized that users
of hand-fired, wood-burning equipment have a great deal of
influence over the performance of any wood-burning appliance. Some
compromises in realism have been made in the interest of providing
a reliable and repeatable test method.
6.0 Test Equipment
6.1 Scale. A platform scale capable of weighing the appliance
under test and associated parts and accessories when completely
filled with water to an accuracy of ±1.0 pound (±0.5 kg).
6.2 Heat Exchanger. A water-to-water heat exchanger capable of
dissipating the expected heat output from the system under
test.
6.3 Water Temperature Difference Measurement. A Type - T
'special limits' thermopile with a minimum of 5 pairs of junctions
shall be used to measure the temperature difference in water
entering and leaving the heat exchanger. The temperature difference
measurement uncertainty of this type of thermopile is equal to or
less than ±0.50 °F (±0.25 °C). Other temperature measurement
methods may be used if the temperature difference measurement
uncertainty is equal to or less than ±0.50 °F (±0.25 °C).
6.4 Water Flow Meter. A water flow meter shall be installed in
the inlet to the load side of the heat exchanger. The flow meter
shall have an accuracy of ±1 percent of measured flow.
6.4.1 Optional - Appliance Side Water Flow Meter. A water flow
meter with an accuracy of ±1 percent of the flow rate is
recommended to monitor supply side water flow rate.
6.5 Optional Recirculation Pump. Circulating pump used during
test to prevent stratification of liquid being heated.
6.6 Water Temperature Measurement - Thermocouples or other
temperature sensors to measure the water temperature at the inlet
and outlet of the load side of the heat exchanger. Must meet the
calibration requirements specified in section 10.1.
6.7 Wood Moisture Meter - Calibrated electrical resistance meter
capable of measuring test fuel moisture to within 1 percent
moisture content. Must meet the calibration requirements specified
in section 10.4.
6.8 Flue Gas Temperature Measurement - Must meet the
requirements of CSA B415.1-10 (IBR, see § 60.17), clause 6.2.2.
6.9 Test Room Temperature Measurement - Must meet the
requirements of CSA B415.1-10 (IBR, see § 60.17), clause 6.2.1.
6.10 Flue Gas Composition Measurement - Must meet the
requirements of CSA B415.1-10 (IBR, see § 60.17), clauses 6.3.1
through 6.3.3.
7.0 Safety
7.1 These tests involve combustion of wood fuel and substantial
release of heat and products of combustion. The heating system also
produces large quantities of very hot water and the potential for
steam production and system pressurization. Appropriate precautions
must be taken to protect personnel from burn hazards and
respiration of products of combustion.
8.0 Sampling, Test Specimens and Test Appliances
8.1 Test specimens shall be supplied as complete appliances
including all controls and accessories necessary for installation
in the test facility. A full set of specifications and design and
assembly drawings shall be provided when the product is to be
placed under certification of a third-party agency. The
manufacturer's written installation and operating instructions are
to be used as a guide in the set-up and testing of the
appliance.
9.0 Preparation of Test Equipment
9.1 The appliance is to be placed on a scale capable of weighing
the appliance fully loaded with a resolution of ±1.0 lb (0.5
kg).
9.2 The appliance shall be fitted with the type of chimney
recommended or provided by the manufacturer and extending to 15
±0.5 feet (4.6 ±0.15 m) from the upper surface of the scale. If no
flue or chimney system is recommended or provided by the
manufacturer, connect the appliance to a flue of a diameter equal
to the flue outlet of the appliance. The flue section from the
appliance flue collar to 8 ±0.5 feet above the scale shall be
single wall stove pipe and the remainder of the flue shall be
double wall insulated class A chimney.
9.3 Optional Equipment Use
9.3.1 A recirculation pump may be installed between connections
at the top and bottom of the appliance to minimize thermal
stratification if specified by the manufacturer. The pump shall not
be installed in such a way as to change or affect the flow rate
between the appliance and the heat exchanger.
9.3.2 If the manufacturer specifies that a thermal control valve
or other device be installed and set to control the return water
temperature to a specific set point, the valve or other device
shall be installed and set per the manufacturer's written
instructions.
9.4 Prior to filling the tank, weigh and record the appliance
mass.
9.5 Heat Exchanger
9.5.1 Plumb the unit to a water-to-water heat exchanger with
sufficient capacity to draw off heat at the maximum rate
anticipated. Route hoses, electrical cables, and instrument wires
in a manner that does not influence the weighing accuracy of the
scale as indicated by placing dead weights on the platform and
verifying the scale's accuracy.
9.5.2 Locate thermocouples to measure the water temperature at
the inlet and outlet of the load side of the heat exchanger.
9.5.3 Install a thermopile meeting the requirements of section
6.3 to measure the water temperature difference between the inlet
and outlet of the load side of the heat exchanger.
9.5.4 Install a calibrated water flow meter in the heat
exchanger load side supply line. The water flow meter is to be
installed on the cooling water inlet side of the heat exchanger so
that it will operate at the temperature at which it is
calibrated.
9.5.5 Place the heat exchanger in a box with 2 in. (50 mm) of
expanded polystyrene (EPS) foam insulation surrounding it to
minimize heat losses from the heat exchanger.
9.5.6 The reported efficiency and heat output rate shall be
based on measurements made on the load side of the heat
exchanger.
9.5.7 Temperature instrumentation per section 6.6 shall be
installed in the appliance outlet and return lines. The average of
the outlet and return water temperature on the supply side of the
system shall be considered the average appliance temperature for
calculation of heat storage in the appliance (TFavg and TIavg).
Installation of a water flow meter in the supply side of the system
is optional.
9.6 Fill the system with water. Determine the total weight of
the water in the appliance when the water is circulating. Verify
that the scale indicates a stable weight under operating
conditions. Make sure air is purged properly.
10.0 Calibration and Standardization
10.1 Water Temperature Sensors. Temperature measuring equipment
shall be calibrated before initial use and at least semi-annually
thereafter. Calibrations shall be in compliance with National
Institute of Standards and Technology (NIST) Monograph 175,
Standard Limits of Error.
10.2 Heat Exchanger Load Side Water Flow Meter.
10.2.1 The heat exchanger load side water flow meter shall be
calibrated within the flow range used for the test run using NIST
traceable methods. Verify the calibration of the water flow meter
before and after each test run and at least once during each test
run by comparing the water flow rate indicated by the flow meter to
the mass of water collected from the outlet of the heat exchanger
over a timed interval. Volume of the collected water shall be
determined based on the water density calculated from section 13,
Eq. 8, using the water temperature measured at the flow meter. The
uncertainty in the verification procedure used shall be 1 percent
or less. The water flow rate determined by the collection and
weighing method shall be within 1 percent of the flow rate
indicated by the water flow meter.
10.3 Scales. The scales used to weigh the appliance and test
fuel charge shall be calibrated using NIST traceable methods at
least once every 6 months.
10.4 Moisture Meter. The moisture meter shall be calibrated per
the manufacturer's instructions and checked before each use.
10.5 Flue Gas Analyzers - In accordance with CSA B415.1-10 (IBR,
see § 60.17), clause 6.8.
11.0 Conditioning
11.1 Prior to testing, the appliance is to be operated for a
minimum of 50 hours using a medium heat draw rate. The conditioning
may be at the manufacturer's facility prior to the certification
test. If the conditioning is at the certification test laboratory,
the pre-burn for the first test can be included as part of the
conditioning requirement. If conditioning is included in pre-burn,
then the appliance shall be aged with fuel meeting the
specifications outlined in sections 12.2 with a moisture content
between 19 and 25 percent on a dry basis. Operate the appliance at
a medium burn rate (Category II or III) for at least 10 hours for
noncatalytic appliances and 50 hours for catalytic appliances.
Record and report hourly flue gas exit temperature data and the
hours of operation. The aging procedure shall be conducted and
documented by a testing laboratory.
12.0 Procedure
12.1 Appliance Installation. Assemble the appliance and parts in
conformance with the manufacturer's written installation
instructions. Clean the flue with an appropriately sized, wire
chimney brush before each certification test series.
12.2 Fuel. Test fuel charge fuel shall be red (Quercus ruba
L.) or white (Quercus alba) oak 19 to 25 percent
moisture content on a dry basis. Piece length shall be 80 percent
of the firebox depth rounded down to the nearest 1 inch (25mm)
increment. For example, if the firebox depth is 46 inches (1168mm)
the 4 × 4 piece length would be 36 inches (46 inches × 0.8 = 36.8
inches rounded down to 36 inches). Pieces are to be placed in the
firebox parallel to the longest firebox dimension. For fireboxes
with sloped surfaces that create a non-uniform firebox length, the
piece length shall be adjusted for each layer based on 80 percent
of the length at the level where the layer is placed. Pieces are to
be spaced 3/4 inches (19 mm) apart on all faces. The first fuel
layer may be assembled using fuel units consisting of multiple 4 ×
4s consisting of single pieces with bottom and side spacers of 3 or
more pieces if needed for a stable layer. The second layer may
consist of fuel units consisting of no more than two pieces with
spacers attached on the bottom and side. The top two layers of the
fuel charge must consist of single pieces unless the fuel charge is
only three layers. In that instance only the top layer must consist
of single units. Three-quarter inch (19 mm) by 1.5 inch (38 mm)
spacers shall be attached to the bottom of piece to maintain a 3/4
inch (19 mm) separation. When a layer consists of two or more units
of 4 × 4s an additional 3/4 inch (19 mm) thick by 1.5 inch (38 mm)
wide spacer shall be attached to the vertical face of each end of
one 4 × 4, such that the 3/4 inch (19 mm) space will be maintained
when two 4 × 4 units or pieces are loaded side by side. In cases
where a layer contains an odd number of 4 × 4s one piece shall not
be attached, but shall have spacers attached in a manner that will
provide for the 3/4 inch (19 mm) space to be maintained (See Figure
1). Spacers shall be attached perpendicular to the length of the 4
× 4s such that the edge of the spacer is 1 ± 0.25 inch from the end
of the 4 × 4s in the previous layers. Spacers shall be red or white
oak and will be attached with either nails (non-galvanized), brads
or oak dowels. The use of kiln-dried wood is not allowed.
12.2.1 Using a fuel moisture meter as specified in section 6.7
of the test method, determine the fuel moisture for each test fuel
piece used for the test fuel load by averaging at least five fuel
moisture meter readings measured parallel to the wood grain.
Penetration of the moisture meter insulated electrodes for all
readings shall be 1/4 the thickness of the fuel piece or 19 mm (
3/4 in.), whichever is lesser. One measurement from each of three
sides shall be made at approximately 3 inches from each end and the
center. Two additional measurements shall be made centered between
the other three locations. Each individual moisture content reading
shall be in the range of 18 to 28 percent on a dry basis. The
average moisture content of each piece of test fuel shall be in the
range of 19 to 25 percent. It is not required to measure the
moisture content of the spacers. Moisture shall not be added to
previously dried fuel pieces except by storage under high humidity
conditions and temperature up to 100 °F. Fuel moisture shall be
measured within 4 hours of using the fuel for a test.
12.2.2 Firebox Volume. Determine the firebox volume in cubic
feet. Firebox volume shall include all areas accessible through the
fuel loading door where firewood could reasonably be placed up to
the horizontal plane defined by the top of the loading door. A
drawing of the firebox showing front, side and plan views or an
isometric view with interior dimensions shall be provided by the
manufacturer and verified by the laboratory. Calculations for
firebox volume from computer aided design (CAD) software programs
are acceptable and shall be included in the test report if used. If
the firebox volume is calculated by the laboratory the firebox
drawings and calculations shall be included in the test report.
12.2.3 Test Fuel Charge. Test fuel charges shall be determined
by multiplying the firebox volume by 10 pounds (4.54 kg) per ft 3
(28L), or a higher load density as recommended by the
manufacturer's printed operating instructions, of wood (as used wet
weight). Select the number of pieces of standard fuel that most
nearly match this target weight. This is the standard fuel charge
for all tests. For example, if the firebox loading area volume is
10 ft 3 (280L) and the firebox depth is 46 inches (1168 mm), test
fuel charge target is 100 lbs (45 kg) minimum and the piece length
is 36 inches (914 mm). If eight 4 × 4s, 36 inches long weigh 105
lbs (48 kg), use 8 pieces for each test fuel charge. All test fuel
charges will be of the same configuration.
12.3 Sampling Equipment. Prepare the particulate emission
sampling equipment as defined by ASTM E2515-11 Standard Test
Method for Determination of Particulate Matter Emissions Collected
in a Dilution Tunnel (IBR, see § 60.17). Upon request,
four-inch filters may be used. Upon request, Teflon membrane
filters or Teflon-coated glass fiber filters may be used.
12.4 Appliance Startup. The appliance shall be fired with wood
fuel of any species, size and moisture content at the laboratories'
discretion to bring it up to operating temperature. Operate the
appliance until the water is heated to the upper operating control
limit and has cycled at least two times. Then remove all unburned
fuel, zero the scale and verify the scales accuracy using dead
weights.
12.4.1 Pretest Burn Cycle. Reload appliance with oak wood and
allow it to burn down to the specified coal bed weight. The pretest
burn cycle fuel charge weight shall be within ±10 percent of the
test fuel charge weight. Piece size and length shall be selected
such that charcoalization is achieved by the time the fuel charge
has burned down to the required coal bed weight. Pieces with a
maximum thickness of approximately 2 inches have been found to be
suitable. Charcoalization is a general condition of the test fuel
bed evidenced by an absence of large pieces of burning wood in the
coal bed and the remaining fuel pieces being brittle enough to be
broken into smaller charcoal pieces with a metal poker.
Manipulations to the fuel bed prior to the start of the test run
are to be done to achieve charcoalization while maintaining the
desired heat output rate. During the pre-test burn cycle and at
least one hour prior to starting the test run, adjust water flow to
the heat exchanger to establish the target heat draw for the test.
For the first test run the heat draw rate shall be equal to the
manufacturer's rated heat output capacity.
12.4.1.1 Allowable Adjustments. Fuel addition or subtractions,
and coal bed raking shall be kept to a minimum but are allowed up
to 15 minutes prior to the start of the test run. For the purposes
of this method, coal bed raking is the use of a metal tool (poker)
to stir coals, break burning fuel into smaller pieces, dislodge
fuel pieces from positions of poor combustion, and check for the
condition of charcoalization. Record all adjustments to and
additions or subtractions of fuel, and any other changes to the
appliance operations that occur during pretest ignition period.
During the 15-minute period prior to the start of the test run, the
wood heater loading door shall not be open more than a total of 1
minute. Coal bed raking is the only adjustment allowed during this
period.
12.4.2 Coal Bed Weight. The appliance is to be loaded with the
test fuel charge when the coal bed weight is between 10 percent and
20 percent of the test fuel charge weight. Coals may be raked as
necessary to level the coal bed but may only be raked and stirred
once between 15 to 20 minutes prior to the addition of the test
fuel charge.
12.5 Test Runs. For all test runs, the return water temperature
to the hydronic heater must be equal to or greater than 120 °F.
Aquastat or other heater output control device settings that are
adjustable shall be set using manufacturer specifications, either
as factory set or in accordance with the owner's manual, and shall
remain the same for all burn categories.
Complete a test run in each heat output rate category, as
follows:
12.5.1 Test Run Start. Once the appliance is operating normally
and the pretest coal bed weight has reached the target value per
section 12.4.2, tare the scale and load the full test charge into
the appliance. Time for loading shall not exceed 5 minutes. The
actual weight of the test fuel charge shall be measured and
recorded within 30 minutes prior to loading. Start all sampling
systems.
12.5.1.1 Record all water temperatures, differential water
temperatures and water flow rates at time intervals of one minute
or less.
12.5.1.2 Record particulate emissions data per the requirements
of ASTM E2515 (IBR, see § 60.17).
12.5.1.3 Record data needed to determine overall efficiency
(SLM) per the requirements of CSA B415.1-10 (IBR, see § 60.17),
clauses 6.2.1, 6.2.2, 6.3, 8.5.7, 10.4.3 (a), 10.4.3(f), and
13.7.9.3
12.5.1.3.1 Measure and record the test room air temperature in
accordance with the requirements of CSA B415.1-10 (IBR, see §
60.17), clauses 6.2.1, 8.5.7 and 10.4.3 (g).
12.5.1.3.2 Measure and record the flue gas temperature in
accordance with the requirements of CSA B415.1-10 (IBR, see §
60.17), clauses 6.2.2, 8.5.7 and 10.4.3 (f).
12.5.1.3.3 Determine and record the carbon monoxide (CO) and
carbon dioxide (CO2) concentrations in the flue gas in accordance
with CSA B415.1-10 (IBR, see § 60.17), clauses 6.3, 8.5.7 and
10.4.3 (i) and (j).
12.5.1.3.4 Measure and record the test fuel weight per the
requirements of CSA B415.1-10 (IBR, see § 60.17), clauses 8.5.7 and
10.4.3 (h).
12.5.1.3.5 Record the test run time per the requirements of CSA
B415.1-10 (IBR, see § 60.17), clauses 10.4.3 (a).
12.5.1.4 Monitor the average heat output rate on the load side
of the heat exchanger. If the heat output rate gets close to the
upper or lower limit of the target range (±5 percent) adjust the
water flow through the heat exchanger to compensate. Make changes
as infrequently as possible while maintaining the target heat
output rate. The first test run shall be conducted at the Category
IV heat output rate to validate that the appliance is capable of
producing the manufacturer's rated heat output capacity.
12.5.2 Test Fuel Charge Adjustment. It is acceptable to adjust
the test fuel charge (i.e., reposition) once during a test
run if more than 60 percent of the initial test fuel charge weight
has been consumed and more than 10 minutes have elapsed without a
measurable (1 lb or 0. 5 kg) weight change while the operating
control is in the demand mode. The time used to make this
adjustment shall be less than 60 seconds.
12.5.3 Test Run Completion. The test run is completed when the
remaining weight of the test fuel charge is 0.0 lb (0.0 kg). End
the test run when the scale has indicated a test fuel charge weight
of 0.0 lb (0.0 kg) or less for 30 seconds.
12.5.3.1 At the end of the test run, stop the particulate
sampling train and overall efficiency (SLM) measurements, and
record the run time, and all final measurement values.
12.5.4 Heat Output Capacity Validation. The first test run must
produce a heat output rate that is within 10 percent of the
manufacturer's rated heat output capacity (Category IV) throughout
the test run and an average heat output rate within 5 percent of
the manufacturer's rated heat output capacity. If the appliance is
not capable of producing a heat output within these limits, the
manufacturer's rated heat output capacity is considered not
validated and testing is to be terminated. In such cases, the tests
may be restarted using a lower heat output capacity if requested by
the manufacturer.
12.5.5 Additional Test Runs. Using the manufacturer's rated heat
output capacity as a basis, conduct a test for additional heat
output categories as specified in section 4.3. It is not required
to run these tests in any particular order.
12.5.6 Alternative Heat Output Rate for Category I. If an
appliance cannot be operated in the Category I heat output range
due to stopped combustion, two test runs shall be conducted at heat
output rates within Category II, provided that the completed test
run burn rate is no greater than the burn rate expected in home
use. If this rate cannot be achieved, the test is not valid.
When the alternative heat output rate is used, the weightings
for the weighted averages indicated in Table 2 shall be the average
of the Category I and II weightings and shall be applied to both
Category II results. The two completed runs in Category II will be
deemed to meet the requirement for runs completed in both Category
I and Category II. Appliances that are not capable of operation
within Category II (<25 percent of maximum) cannot be evaluated
by this test method. The test report must include full
documentation and discussion of the attempted runs, completed rums
and calculations.
12.5.6.1 Stopped Fuel Combustion. Evidence that an appliance
cannot be operated at a Category I heat output rate due to stopped
fuel combustion shall include documentation of two or more attempts
to operate the appliance in burn rate Category I and fuel
combustion has stopped prior to complete consumption of the test
fuel charge. Stopped fuel combustion is evidenced when an elapsed
time of 60 minutes or more has occurred without a measurable (1 lb
or 0.5 kg) weight change in the test fuel charge while the
appliance operating control is in the demand mode. Report the
evidence and the reasoning used to determine that a test in burn
rate Category I cannot be achieved. For example, two unsuccessful
attempts to operate at an output rate of 10 percent of the rated
output capacity are not sufficient evidence that burn rate Category
I cannot be achieved. Note that section 12.5.6 requires that the
completed test run burn rate can be no greater than the burn rate
expected in home use. If this rate cannot be achieved, the test is
not valid.
12.5.7 Appliance Overheating. Appliances shall be capable of
operating in all heat output categories without overheating to be
rated by this test method. Appliance overheating occurs when the
rate of heat withdrawal from the appliance is lower than the rate
of heat production when the unit control is in the idle mode. This
condition results in the water in the appliance continuing to
increase in temperature well above the upper limit setting of the
operating control. Evidence of overheating includes: 1 hour or more
of appliance water temperature increase above the upper temperature
set-point of the operating control, exceeding the temperature limit
of a safety control device (independent from the operating
control), boiling water in a non-pressurized system or activation
of a pressure or temperature relief valve in a pressurized
system.
12.6 Additional Test Runs. The testing laboratory may conduct
more than one test run in each of the heat output categories
specified in section 4.3.1. If more than one test run is conducted
at a specified heat output rate, the results from at least
two-thirds of the test runs in that heat output rate category shall
be used in calculating the weighted average emission rate (See
section 14.1.14). The measurement data and results of all test runs
shall be reported regardless of which values are used in
calculating the weighted average emission rate.
13.0 Calculation of Results 13.1 Nomenclature ET - Total
particulate emissions for the full test run as determined per ASTM
E2515-11 (IBR, see § 60.17) in grams Eg/MJ - Emissions rate in
grams per megajoule of heat output Elb/mmBtu output - Emissions
rate in pounds per million Btu of heat output Eg/kg - Emissions
factor in grams per kilogram of dry fuel burned Eg/hr - Emissions
factor in grams per hour HHV - Higher heating value of fuel = 8600
Btu/lb (19.990 MJ/kg) LHV - Lower heating value of fuel = 7988
Btu/lb (18.567 MJ/kg) ΔT - Temperature difference between water
entering and exiting the heat exchanger Qout - Total heat output in
BTU's (megajoules) Qin - Total heat input available in test fuel
charge in BTU (megajoules) M - Mass flow rate of water in lb/min
(kg/min) Vi - Volume of water indicated by a totalizing flow meter
at the ith reading in gallons (liters) Vf - Volumetric flow rate of
water in heat exchange system in gallons per minute (liters/min) Θ
- Total length of test run in hours ti - Data sampling interval in
minutes ηdel - Delivered heating efficiency in percent Fi -
Weighting factor for heat output category i (See Table 2) T1 -
Temperature of water at the inlet on the supply side of the heat
exchanger T2 - Temperature of the water at the outlet on the supply
side of the heat exchanger T3 - Temperature of water at the inlet
to the load side of the heat exchanger TIavg - Average temperature
of the appliance and water at start of the test TFavg - Average
temperature of the appliance and water at the end of the test
MC - Fuel
moisture content in percent dry basis MCi - Average moisture
content of individual 4 × 4 fuel pieces in percent dry basis MCsp -
Moisture content of spacers assumed to be 10 percent dry basis σ -
Density of water in pounds per gallon Cp - Specific heat of water
in Btu/lb, °F Csteel - Specific heat of steel (0.1 Btu/lb, ºF)
Wfuel - Fuel charge weight in pounds (kg) Wi - Weight of individual
fuel 4 × 4 pieces in pounds (kg) Wsp - Weight of all spacers used
in a fuel load in pounds (kg) Wapp - Weight of empty appliance in
pounds Wwa - Weight of water in supply side of the system in pounds
13.2 After the test is completed, determine the particulate
emissions ET in accordance with ASTM E2515-11 (IBR, see §
60.17).
13.3 Determine Average Fuel Load Moisture Content 13.4 Determine
heat input 13.5 Determine
Heat Output and Efficiency 13.5.1 Determine heat output as: Qout =
Σ [Heat output determined for each sampling time interval] + Change
in heat stored in the appliance. Note:
The subscript (i) indicates the parameter value for sampling
time interval ti.
Mi = Mass flow rate = gal/min × density of water (lb/gal) = lb/min
Csteel = 0.1
Btu/lb, ° F Note:
Vi is the total water volume at the end of interval i and Vi-1
is the total water volume at the beginning of the time interval.
This calculation is necessary when a totalizing type water meter is
used.
13.5.2 Determine heat output rate as: 13.5.3 Determine
emission rates and emission factors as: 13.5.4 Determine
delivered efficiency as: 13.5.5 Determine
ηSLM - Overall Efficiency (SLM) using Stack Loss
For determination of the average overall thermal efficiency
(ηSLM) for the test run, use the data collected over the full test
run and the calculations in accordance with CSA B415.1-10 (IBR, see
§ 60.17), clause 13.7 except for 13.7.2 (e), (f), (g), and (h), use
the following average fuel properties for oak: percent C = 50.0,
percent H = 6.6, percent O = 43.2, percent ash = 0.2 percent. The
averaging period for determination of efficiency by the stack loss
method allows averaging over 10 minute time periods for flue gas
temperature, flue gas CO2, and flue gas CO for the determination of
the efficiency. However, under some cycling conditions the “on”
period may be short relative to this 10 minute period. For this
reason, during cycling operation the averaging period for these
parameters may not be longer than the burner on period divided by
10. The averaging period need not be shorter than one minute.
During the off period, under cycling operation, the averaging
periods specified may be used. Where short averaging times are
used, however, the averaging period for fuel consumption may still
be at 10 minutes. This average wood consumption rate shall be
applied to all of the smaller time intervals included.
13.5.5.1 Whenever the CSA B415.1-10 (IBR, see § 60.17) overall
efficiency is found to be lower than the overall efficiency based
on load side measurements, as determined by Eq. 16 of this method,
section 14.1.7 of the test report must include a discussion of the
reasons for this result.
13.6 Weighted Average Emissions and Efficiency
13.6.1 Determine the weighted average emission rate and
delivered efficiency from the individual tests in the specified
heat output categories. The weighting factors (Fi) are derived from
an analysis of ASHRAE bin data which provides details of normal
building heating requirements in terms of percent of design
capacity and time in a particular capacity range - or “bin” - over
the course of a heating season. The values used in this method
represent an average of data from several cities located in the
northern United States.
13.7 Average Heat Output (Qout-8hr) and Efficiency ((ηavg-8hr)
for 8 hour burn time.
13.7.1 Units tested under this standard typically require
infrequent fuelling, 8 to 12 hours intervals being typical. Rating
unit's based on an average output sustainable over an 8 hour
duration will assist consumers in appropriately sizing units to
match the theoretical heat demand of their application.
13.7.2 Calculations:
Where: Y1
= Test duration just above 8 hrs Y2 = Test duration just below 8
hrs X1 = Actual load for duration Y1 X2 = Actual load for duration
Y2 ηdel1 = Average delivered efficiency for duration Y1 ηdel2 =
Average delivered efficiency for duration Y2
13.7.2.1 Determine the test durations and actual load for each
category as recorded in Table 1A.
13.7.2.2 Determine the data point that has the nearest duration
greater than 8 hrs.
X1 = Actual load, Y1 = Test duration, and ηdel1 = Average delivered
efficiency for this data point
13.7.2.3 Determine the data point that has the nearest duration
less than 8 hours.
X2 = Actual load, Y2 = Test duration, and ηdel2 = Average delivered
efficiency for this data point
13.7.2.4 Example:
Category Actual Load Duration
[Category Actual Load Duration
ηdel]
(Btu/Hr)
(Hr)
(%)
1 15,000
10.2
70.0
2 26,000
8.4
75.5
3 50,000
6.4
80.1
4 100,000
4.7
80.9
Category 2 duration is just above 8 hours, therefore: X1 =
26,000 Btu/hr, ηdel1 = 75.5% and Y1 = 8.4 hrs
Category 3 duration is just below 8 hours, therefore: X2 =
50,000 Btu/hr, ηdel2 = 80.1% and Y2 = 6.4 hrs
For each minute of the test period, the carbon monoxide emission
rate shall be calculated as:
Total CO emissions for each of the three test periods (CO_1,
CO_2, CO_3) shall be calculated as the sum of the emission rates
for each of the 1 minute intervals.
Total CO emission for the test run, COT, shall be calculated as
the sum of CO_1, CO_2, and CO_3.
14.0 Report
14.1.1 The report shall include the following.
14.1.2 Name and location of the laboratory conducting the
test.
14.1.3 A description of the appliance tested and its condition,
date of receipt and dates of tests.
14.1.4 A statement that the test results apply only to the
specific appliance tested.
14.1.5 A statement that the test report shall not be reproduced
except in full, without the written approval of the laboratory.
14.1.6 A description of the test procedures and test equipment
including a schematic or other drawing showing the location of all
required test equipment. Also, a description of test fuel sourcing,
handling and storage practices shall be included.
14.1.7 Details of deviations from, additions to or exclusions
from the test method, and their data quality implications on the
test results (if any), as well as information on specific test
conditions, such as environmental conditions.
14.1.8 A list of participants and observers present for the
tests.
14.1.9 Data and drawings indicating the fire box size and
location of the fuel charge.
14.1.10 Drawings and calculations used to determine firebox
volume.
14.1.11 Information for each test run fuel charge including
piece size, moisture content, and weight.
14.1.12 All required data for each test run shall be provided in
spreadsheet format. Formulae used for all calculations shall be
accessible for review.
14.1.13 Test run duration for each test.
14.1.14 Calculated results for delivered efficiency at each burn
rate and the weighted average emissions reported as total emissions
in grams, pounds per mm Btu of delivered heat, grams per MJ of
delivered heat, grams per kilogram of dry fuel and grams per hour.
Results shall be reported for each heat output category and the
weighted average.
14.1.15 Tables 1A, 1B, 1C and Table 2 must be used for
presentation of results in test reports.
14.1.16 A statement of the estimated uncertainty of measurement
of the emissions and efficiency test results.
14.1.17 Raw data, calibration records, and other relevant
documentation shall be retained by the laboratory for a minimum of
7 years.
15.0 Precision and Bias
15.1 Precision - It is not possible to specify the precision of
the procedure in Method 28WHH because the appliance operation and
fueling protocols and the appliances themselves produce variable
amounts of emissions and cannot be used to determine
reproducibility or repeatability of this measurement method.
15.2 Bias - No definitive information can be presented on the
bias of the procedure in Method 28WHH for measuring solid fuel
burning hydronic heater emissions because no material having an
accepted reference value is available.
Test Method 28WHH
for Certification of Cord Wood-Fired Hydronic Heating Appliances
With Partial Thermal Storage: Measurement of Particulate Matter
(PM) and Carbon Monoxide (CO) Emissions and Heating Efficiency of
Wood-Fired Hydronic Heating Appliances With Partial Thermal Storage
1.0 Scope and Application
1.1 This test method applies to wood-fired hydronic heating
appliances with heat storage external to the appliance. The units
typically transfer heat through circulation of a liquid heat
exchange media such as water or a water-antifreeze mixture.
Throughout this document, the term “water” will be used to denote
any of the heat transfer liquids approved for use by the
manufacturer.
1.2 The test method measures PM and CO emissions and delivered
heating efficiency at specified heat output rates referenced
against the appliance's rated heating capacity as specified by the
manufacturer and verified under this test method.
1.3 PM emissions are measured by the dilution tunnel method as
specified in the EPA Method 28WHH and the standards referenced
therein with the exceptions noted in section 12.5.9. Delivered
efficiency is measured by determining the fuel energy input and
appliance output. Heat output is determined through measurement of
the flow rate and temperature change of water circulated through a
heat exchanger external to the appliance and the increase in energy
of the external storage. Heat input is determined from the mass of
dry wood fuel and its higher heating value (HHV). Delivered
efficiency does not attempt to account for pipeline loss.
1.4 Products covered by this test method include both
pressurized and non-pressurized hydronic heating appliances
intended to be fired with wood and for which the manufacturer
specifies for indoor or outdoor installation. The system, which
includes the heating appliance and external storage, is commonly
connected to a heat exchanger by insulated pipes and normally
includes a pump to circulate heated liquid. These systems are used
to heat structures such as homes, barns and greenhouses. They also
provide heat for domestic hot water, spas and swimming pools.
1.5 Distinguishing features of products covered by this standard
include:
1.5.1 The manufacturer specifies the application for either
indoor or outdoor installation.
1.5.2 A firebox with an access door for hand loading of
fuel.
1.5.3 Typically an aquastat mounted as part of the appliance
that controls combustion air supply to maintain the liquid in the
appliance within a predetermined temperature range provided
sufficient fuel is available in the firebox. The appliance may be
equipped with other devices to control combustion.
1.5.4 A chimney or vent that exhausts combustion products from
the appliance.
1.5.5 A liquid storage system, typically water, which is not
large enough to accept all of the heat produced when a full load of
wood is burned and the storage system starts a burn cycle at 125
°F.
1.5.6 The heating appliances require external thermal storage
and these units will only be installed as part of a system which
includes thermal storage. The manufacturer specifies the minimum
amount of thermal storage required. However, the storage system
shall be large enough to ensure that the boiler (heater) does not
cycle, slumber, or go into an off-mode when operated in a Category
III load condition (See section 4.3).
1.6 The values stated are to be regarded as the standard whether
in I-P or SI units. The values given in parentheses are for
information only.
2.0 Summary of Method and References
2.1 PM and CO emissions are measured from a wood-fired hydronic
heating appliance burning a prepared test fuel charge in a test
facility maintained at a set of prescribed conditions. Procedures
for determining heat output rates, PM and CO emissions, and
efficiency and for reducing data are provided.
2.2 Referenced Documents
2.2.1 EPA Standards
2.2.1.1 Method 28 Certification and Auditing of Wood Heaters
2.2.1.2 Method 28WHH Measurement of Particulate Emissions and
Heating Efficiency of Wood-Fired Hydronic Heating Appliances and
the Standards Referenced therein.
2.2.2 Other Standards
2.2.2.1 CSA-B415.1-10 Performance Testing of
Solid-Fuel-Burning Heating Appliances
3.0 Terminology 3.1 Definitions
3.1.1 Hydronic Heating - A heating system in which a heat source
supplies energy to a liquid heat exchange media such as water that
is circulated to a heating load and returned to the heat source
through pipes.
3.1.2 Aquastat - A control device that opens or closes a circuit
to control the rate of fuel consumption in response to the
temperature of the heating media in the heating appliance.
3.1.3 Delivered Efficiency - The percentage of heat available in
a test fuel charge that is delivered to a simulated heating load or
the storage system as specified in this test method.
3.1.4 Emission Factor - The emission of a pollutant expressed in
mass per unit of energy (typically) output from the
boiler/heater.
3.1.5 Emission Index - The emission of a pollutant expressed in
mass per unit mass of fuel used.
3.1.6 Emission Rate - The emission of a pollutant expressed in
mass per unit time
3.1.7 Manufacturer's Rated Heat Output Capacity - The value in
Btu/hr (MJ/hr) that the manufacturer specifies that a particular
model of hydronic heating appliance is capable of supplying at its
design capacity as verified by testing, in accordance with section
12.5.4.
3.1.8 Heat Output Rate - The average rate of energy output from
the appliance during a specific test period in Btu/hr (MJ/hr).
3.1.9 Firebox - The chamber in the appliance in which the test
fuel charge is placed and combusted.
3.1.10 NIST - National Institute of Standards and
Technology.
3.1.11 Test Fuel Charge - The collection of test fuel placed in
the appliance at the start of the emission test run.
3.1.12 Test Run - An individual emission test which encompasses
the time required to consume the mass of the test fuel charge. The
time of the test run also considers the time for the energy to be
drawn from the thermal storage.
3.1.13 Test Run Under “Cold-to-Cold” Condition - Under this test
condition the test fuel is added into an empty chamber along with
kindling and ignition materials (paper). The boiler/heater at the
start of this test is typically 125° to 130 °F.
3.1.14 Test Run Under “Hot-to-Hot” Condition - Under this test
condition the test fuel is added onto a still-burning bed of
charcoals produced in a pre-burn period. The boiler/heater water is
near its operating control limit at the start of the test.
3.1.15 Overall Efficiency, also known as Stack Loss Efficiency -
The efficiency for each test run as determined using the CSA
B415.1-10 (IBR, see § 60.17) stack loss method (SLM).
3.1.16 Phases of a Burn Cycle - The “startup phase” is defined
as the period from the start of the test until 15 percent of the
test fuel charge is consumed. The “steady-state phase” is defined
as the period from the end of the startup phase to a point at which
80 percent of the test fuel charge is consumed. The “end phase” is
defined as the time from the end of the steady-state period to the
end of the test.
3.1.17 Thermopile - A device consisting of a number of
thermocouples connected in series, used for measuring differential
temperature.
3.1.18 Slumber Mode - This is a mode in which the temperature of
the water in the boiler/heater has exceeded the operating control
limit and the control has changed the boiler/heater fan speed,
dampers, and/or other operating parameters to minimize the heat
output of the boiler/heater.
4.0 Summary of Test Method
4.1 Dilution Tunnel. Emissions are determined using the
“dilution tunnel” method specified in EPA Method 28WHH and the
standards referenced therein. The flow rate in the dilution tunnel
is maintained at a constant level throughout the test cycle and
accurately measured. Samples of the dilution tunnel flow stream are
extracted at a constant flow rate and drawn through high efficiency
filters. The filters are dried and weighed before and after the
test to determine the emissions collected and this value is
multiplied by the ratio of tunnel flow to filter flow to determine
the total particulate emissions produced in the test cycle.
4.2 Efficiency. The efficiency test procedure takes advantage of
the fact that this type of system delivers heat through circulation
of the heated liquid (water) from the system to a remote heat
exchanger (e.g. baseboard radiators in a room) and back to
the system. Measurements of the cooling water temperature
difference as it enters and exits the test system heat exchanger
along with the measured flow rate allow for an accurate
determination of the useful heat output of the appliance. Also
included in the heat output is the change in the energy content in
the storage system during a test run. Energy input to the appliance
during the test run is determined by weight of the test fuel
charge, adjusted for moisture content, multiplied by the higher
heating value. Additional measurements of the appliance weight and
temperature at the beginning and end of a test cycle are used to
correct for heat stored in the appliance. Overall efficiency (SLM)
is determined using the CSA B415.1-10 (IBR, see § 60.17) stack loss
method for data quality assurance purposes.
4.3 Operation. Four test categories are defined for use in this
method. These are:
4.3.1 Category I: A heat output of 15 percent or less of
manufacturer's rated heat output capacity.
4.3.2 Category II: A heat output of 16 percent to 24 percent of
manufacturer's rated heat output capacity.
4.3.3 Category III: A heat output of 25 percent to 50 percent of
manufacturer's rated heat output capacity.
4.3.4 Category IV: Manufacturer's Rated Heat Output Capacity.
These heat output categories refer to the output from the system by
way of the load heat exchanger installed for the test. The output
from just the boiler/heater part of the system may be higher for
all or part of a test, as part of this boiler/heater output goes to
storage.
For the Category III and IV runs, appliance operation is
conducted on a hot-to-hot test cycle meaning that the appliance is
brought to operating temperature and a coal bed is established
prior to the addition of the test fuel charge and measurements are
made for each test fuel charge cycle. The measurements are made
under constant heat draw conditions within pre-determined ranges.
No attempt is made to modulate the heat demand to simulate an
indoor thermostat cycling on and off in response to changes in the
indoor environment.
For the Category I and II runs, the unit is tested with a “cold
start.” At the manufacturer's option, the Category II and III runs
may be waived and it may be assumed that the particulate emission
values and efficiency values determined in the startup,
steady-state, and end phases of Category I are applicable in
Categories II and III for the purpose of determining the annual
averages in lb/mmBtu and g/MJ (See section 13). For the annual
average in g/hr, the length of time for stored heat to be drawn
from thermal storage shall be determined for the test load
requirements of the respective category.
All test operations and measurements shall be conducted by
personnel of the laboratory responsible for the submission of the
test report.
5.0 Significance and Use
5.1 The measurement of particulate matter emission and CO rates
is an important test method widely used in the practice of air
pollution control.
5.1.1 These measurements, when approved by state or federal
agencies, are often required for the purpose of determining
compliance with regulations and statutes.
5.1.2 The measurements made before and after design
modifications are necessary to demonstrate the effectiveness of
design changes in reducing emissions and make this standard an
important tool in manufacturers' research and development
programs.
5.2 Measurement of heating efficiency provides a uniform basis
for comparison of product performance that is useful to the
consumer. It is also required to relate emissions produced to the
useful heat production.
5.3 This is a laboratory method and is not intended to be fully
representative of all actual field use. It is recognized that users
of hand-fired, wood-burning equipment have a great deal of
influence over the performance of any wood-burning appliance. Some
compromises in realism have been made in the interest of providing
a reliable and repeatable test method.
6.0 Test Equipment
6.1 Scale. A platform scale capable of weighing the
boiler/heater under test and associated parts and accessories when
completely filled with water to an accuracy of ±1.0 pound (±0.5 kg)
and a readout resolution of ±0.2 pound (±0.1 kg).
6.2 Heat Exchanger. A water-to-water heat exchanger capable of
dissipating the expected heat output from the system under
test.
6.3 Water Temperature Difference Measurement. A Type - T
'special limits' thermopile with a minimum of 5 pairs of junctions
shall be used to measure the temperature difference in water
entering and leaving the heat exchanger. The temperature difference
measurement uncertainty of this type of thermopile is equal to or
less than ±0.50 °F (±0.25 °C). Other temperature measurement
methods may be used if the temperature difference measurement
uncertainty is equal to or less than ±0.50 °F (±0.25 °C). This
measurement uncertainty shall include the temperature sensor,
sensor well arrangement, piping arrangements, lead wire, and
measurement/recording system. The response time of the temperature
measurement system shall be less than half of the time interval at
which temperature measurements are recorded.
6.4 Water Flow Meter. A water flow meter shall be installed in
the inlet to the load side of the heat exchanger. The flow meter
shall have an accuracy of ±1 percent of measured flow.
6.4.1 Optional - Appliance Side Water Flow Meter. A water flow
meter with an accuracy of ±1 percent of the flow rate is
recommended to monitor supply side water flow rate.
6.5 Optional Recirculation Pump. Circulating pump used during
test to prevent stratification, in the boiler/heater, of liquid
being heated.
6.6 Water Temperature Measurement. Thermocouples or other
temperature sensors to measure the water temperature at the inlet
and outlet of the load side of the heat exchanger must meet the
calibration requirements specified in 10.1 of this method.
6.7 Lab Scale. For measuring the moisture content of wood slices
as part of the overall wood moisture determination. Accuracy of
±0.01 pounds.
6.8 Flue Gas Temperature Measurement. Must meet the requirements
of CSA B415.1-10 (IBR, see § 60.17), clause 6.2.2.
6.9 Test Room Temperature Measurement. Must meet the
requirements of CSA B415.1-10 (IBR, see § 60.17), clause 6.2.1.
6.10 Flue Gas Composition Measurement. Must meet the
requirements of CSA B415.1-10 (IBR, see § 60.17), clauses 6.3.1
through 6.3.3.
6.11 Dilution Tunnel CO Measurement. In parallel with the flue
gas composition measurements, the CO concentration in the dilution
tunnel shall also be measured and reported at time intervals not to
exceed one minute. This analyzer shall meet the zero and span drift
requirements of CSA B415.1-10 (IBR, see § 60.17). In addition the
measurement repeatability shall be better than ±15 ppm over the
range of CO levels observed in the dilution tunnel.
7.0 Safety
7.1 These tests involve combustion of wood fuel and substantial
release of heat and products of combustion. The heating system also
produces large quantities of very hot water and the potential for
steam production and system pressurization. Appropriate precautions
must be taken to protect personnel from burn hazards and
respiration of products of combustion.
8.0 Sampling, Test Specimens and Test Appliances
8.1 Test specimens shall be supplied as complete appliances, as
described in marketing materials, including all controls and
accessories necessary for installation in the test facility. A full
set of specifications, installation and operating instructions, and
design and assembly drawings shall be provided when the product is
to be placed under certification of a third-party agency. The
manufacturer's written installation and operating instructions are
to be used as a guide in the set-up and testing of the appliance
and shall be part of the test record.
8.2 The size, connection arrangement, and control arrangement
for the thermal storage shall be as specified in the manufacturer's
documentation. It is not necessary to use the specific storage
system that the boiler/heater will be marketed with. However, the
capacity of the system used in the test cannot be greater than that
specified as the minimum allowable for the boiler/heater.
8.3 All system control settings shall be the as-shipped, default
settings. These default settings shall be the same as those
communicated in a document to the installer or end user. These
control settings and the documentation of the control settings as
to be provided to the installer or end user shall be part of the
test record.
8.4 Where the manufacturer defines several alternatives for the
connection and loading arrangement, one shall be defined in the
appliance documentation as the default or standard installation. It
is expected that this will be the configuration for use with a
simple baseboard heating system. This is the configuration to be
followed for these tests. The manufacturer's documentation shall
define the other arrangements as optional or alternative
arrangements.
9.0 Preparation of Test Equipment
9.1 The appliance is to be placed on a scale capable of weighing
the appliance fully loaded with a resolution of ±0.2 lb (0.1
kg).
9.2 The appliance shall be fitted with the type of chimney
recommended or provided by the manufacturer and extending to 15
±0.5 feet (4.6 ±0.15 m) from the upper surface of the scale. If no
flue or chimney system is recommended or provided by the
manufacturer, connect the appliance to a flue of a diameter equal
to the flue outlet of the appliance. The flue section from the
appliance flue collar to 8 ±0.5 feet above the scale shall be
single wall stove pipe and the remainder of the flue shall be
double wall insulated class A chimney.
9.3 Optional Equipment Use
9.3.1 A recirculation pump may be installed between connections
at the top and bottom of the appliance to minimize thermal
stratification if specified by the manufacturer. The pump shall not
be installed in such a way as to change or affect the flow rate
between the appliance and the heat exchanger.
9.3.2 If the manufacturer specifies that a thermal control valve
or other device be installed and set to control the return water
temperature to a specific set point, the valve or other device
shall be installed and set per the manufacturer's written
instructions.
9.4 Prior to filling the boiler/heater with water, weigh and
record the appliance mass.
9.5 Heat Exchanger
9.5.1 Plumb the unit to a water-to-water heat exchanger with
sufficient capacity to draw off heat at the maximum rate
anticipated. Route hoses and electrical cables and instrument wires
in a manner that does not influence the weighing accuracy of the
scale as indicated by placing dead weights on the platform and
verifying the scale's accuracy.
9.5.2 Locate thermocouples to measure the water temperature at
the inlet and outlet of the load side of the heat exchanger.
9.5.3 Install a thermopile (or equivalent instrumentation)
meeting the requirements of section 6.3 to measure the water
temperature difference between the inlet and outlet of the load
side of the heat exchanger
9.5.4 Install a calibrated water flow meter in the heat
exchanger load side supply line. The water flow meter is to be
installed on the cooling water inlet side of the heat exchanger so
that it will operate at the temperature at which it is
calibrated.
9.5.5 Place the heat exchanger in a box with 2 in. (50 mm) of
expanded polystyrene (EPS) foam insulation surrounding it to
minimize heat losses from the heat exchanger.
9.5.6 The reported efficiency and heat output rate shall be
based on measurements made on the load side of the heat
exchanger.
9.5.7 Temperature instrumentation per section 6.6 shall be
installed in the appliance outlet and return lines. The average of
the outlet and return water temperature on the supply side of the
system shall be considered the average appliance temperature for
calculation of heat storage in the appliance (TFavg and
TIavg). Installation of a water flow meter in the supply
side of the system is optional.
9.6 Storage Tank. The storage tank shall include a
destratification pump as illustrated in Figure 1. The pump will
draw from the bottom of the tank and return to the top as
illustrated. Temperature sensors (TS1 and TS2 in Figure 1) shall be
included to measure the temperature in the recirculation loop. The
valve plan in Figure 1 allows the tank recirculation loop to
operate and the boiler/heater-to-heat exchanger loop to operate at
the same time but in isolation. This would typically be done before
the start of a test or following completion of a test to determine
the end of test average tank temperature. The nominal flow rate in
the storage tank recirculation loop can be estimated based on pump
manufacturers' performance curves and any significant restriction
in the recirculation loop.
9.7 Fill the system with water. Determine the total weight of
the water in the appliance when the water is circulating. Verify
that the scale indicates a stable weight under operating
conditions. Make sure air is purged properly.
10.0 Calibration and Standardization
10.1 Water Temperature Sensors. Temperature measuring equipment
shall be calibrated before initial use and at least semi-annually
thereafter. Calibrations shall be in compliance with National
Institute of Standards and Technology (NIST) Monograph 175,
Standard Limits of Error.
10.2 Heat Exchanger Load Side Water Flow Meter.
10.2.1 The heat exchanger load side water flow meter shall be
calibrated within the flow range used for the test run using
NIST-traceable methods. Verify the calibration of the water flow
meter before and after each test run and at least once during each
test run by comparing the water flow rate indicated by the flow
meter to the mass of water collected from the outlet of the heat
exchanger over a timed interval. Volume of the collected water
shall be determined based on the water density calculated from
section 13, Eq. 12, using the water temperature measured at the
flow meter. The uncertainty in the verification procedure used
shall be 1 percent or less. The water flow rate determined by the
collection and weighing method shall be within 1 percent of the
flow rate indicated by the water flow meter.
10.3 Scales. The scales used to weigh the appliance and test
fuel charge shall be calibrated using NIST-traceable methods at
least once every 6 months.
10.4 Flue Gas Analyzers - In accordance with CSA B415.1-10 (IBR,
see § 60.17), clause 6.8.
11.0 Conditioning
11.1 Prior to testing, an appliance is to be operated for a
minimum of 50 hours using a medium heat draw rate. The conditioning
may be at the manufacturer's facility prior to the certification
test. If the conditioning is at the certification test laboratory,
the pre-burn for the first test can be included as part of the
conditioning requirement. If conditioning is included in pre-burn,
then the appliance shall be aged with fuel meeting the
specifications outlined in section 12.2 with a moisture content
between 19 and 25 percent on a dry basis. Operate the appliance at
a medium heat output rate (Category II or III) for at least 10
hours for non-catalytic appliances and 50 hours for catalytic
appliances. Record and report hourly flue gas exit temperature data
and the hours of operation. The aging procedure shall be conducted
and documented by a testing laboratory.
12.0 Procedure
12.1 Appliance Installation. Assemble the appliance and parts in
conformance with the manufacturer's written installation
instructions. Clean the flue with an appropriately sized, wire
chimney brush before each certification test series.
12.2 Fuel. Test fuel charge fuel shall be red (Quercus ruba
L.) or white (Quercus Alba) oak 19 to 25 percent
moisture content on a dry basis. Piece length shall be 80 percent
of the firebox depth rounded down to the nearest 1 inch (25mm)
increment. For example, if the firebox depth is 46 inches (1168mm)
the piece length would be 36 inches (46 inches × 0.8 = 36.8 inches,
rounded down to 36 inches). Pieces are to be placed in the firebox
parallel to the longest firebox dimension. For fireboxes with
sloped surfaces that create a non-uniform firebox length, the piece
length shall be adjusted for each layer based on 80 percent of the
length at the level where the layer is placed. The test fuel shall
be cord wood with cross section dimensions and weight limits as
defined in CSA B415.1-10 (IBR, see § 60.17), section 8.3, Table 4.
The use of dimensional lumber is not allowed.
12.2.1 Select three pieces of cord wood from the same batch of
wood as the test fuel and the same weight as the average weight of
the pieces in the test load ±1.0 lb. From each of these three
pieces, cut three slices. Each slice shall be 1/2 inch to 3/4 inch
thick. One slice shall be cut across the center of the length of
the piece. The other two slices shall be cut half way between the
center and the end. Immediately measure the mass of each piece in
pounds. Dry each slice in an oven at 220 °F for 24 hours or until
no further weight change occurs. The slices shall be arranged in
the oven so as to provide separation between faces. Remove from the
oven and measure the mass of each piece again as soon as practical,
in pounds.
The moisture content of each slice, on a dry basis, shall be
calculated as:
Where:
WSliceWet = weight of the slice before drying in pounds
WSliceDry = weight of the slice after drying in pounds
MCSlice = moisture content of the slice in % dry basis
The average moisture content of the entire test load (MC) shall
be determined using Eq. 6. Each individual slice shall have a
moisture content in the range of 18 percent to 28 percent on a dry
basis. The average moisture content for the test fuel load shall be
in the range of 19 percent to 25 percent. Moisture shall not be
added to previously dried fuel pieces except by storage under high
humidity conditions and temperature up to 100 °F. Fuel moisture
measurement shall begin within 4 hours of using the fuel batch for
a test. Use of a pin-type meter to estimate the moisture content
prior to a test is recommended.
12.2.2 Firebox Volume. Determine the firebox volume in cubic
feet. Firebox volume shall include all areas accessible through the
fuel loading door where firewood could reasonably be placed up to
the horizontal plane defined by the top of the loading door. A
drawing of the firebox showing front, side and plan views or an
isometric view with interior dimensions shall be provided by the
manufacturer and verified by the laboratory. Calculations for
firebox volume from computer aided design (CAD) software programs
are acceptable and shall be included in the test report if used. If
the firebox volume is calculated by the laboratory the firebox
drawings and calculations shall be included in the test report.
12.2.3 Test Fuel charge. Test fuel charges shall be determined
by multiplying the firebox volume by 10 pounds (4.54 kg) per ft 3
(28L), or a higher load density as recommended by the
manufacturer's printed operating instructions, of wood (as used wet
weight). Select the number of pieces of cord wood that most nearly
match this target weight. However, the test fuel charge cannot be
less than the target of 10 pounds (4.54 kg) per ft 3 (28L).
12.3 Sampling Equipment. Prepare the particulate emission
sampling equipment as defined by EPA Method 28WHH and the standards
referenced therein.
12.4 Appliance Startup. The appliance shall be fired with wood
fuel of any species, size and moisture content, at the laboratory's
discretion, to bring it up to operating temperature. Operate the
appliance until the water is heated to the upper operating control
limit and has cycled at least two times. Then remove all unburned
fuel, zero the scale and verify the scales accuracy using dead
weights.
12.4.1 Startup Procedure for Category III and IV Test Runs,
“Hot-to-Hot.”
12.4.1.1 Pretest t Burn Cycle. Following appliance startup
(section 12.4), reload appliance with oak cord wood and allow it to
burn down to the specified coal bed weight. The pre-test burn cycle
fuel charge weight shall be within ±10 percent of the test fuel
charge weight. Piece size and length shall be selected such that
charcoalization is achieved by the time the fuel charge has burned
down to the required coal bed weight. Pieces with a maximum
thickness of approximately 2 inches have been found to be suitable.
Charcoalization is a general condition of the test fuel bed
evidenced by an absence of large pieces of burning wood in the coal
bed and the remaining fuel pieces being brittle enough to be broken
into smaller charcoal pieces with a metal poker. Manipulations to
the fuel bed prior to the start of the test run are to be done to
achieve charcoalization while maintaining the desired heat output
rate. During the pre-test burn cycle and at least one hour prior to
starting the test run, adjust water flow to the heat exchanger to
establish the target heat draw for the test. For the first test run
the heat draw rate shall be equal to the manufacturer's rated heat
output capacity.
12.4.1.2 Allowable Adjustments. Fuel addition or subtractions,
and coal bed raking shall be kept to a minimum but are allowed up
to 15 minutes prior to the start of the test run. For the purposes
of this method, coal bed raking is the use of a metal tool (poker)
to stir coals, break burning fuel into smaller pieces, dislodge
fuel pieces from positions of poor combustion, and check for the
condition of charcoalization. Record all adjustments to and
additions or subtractions of fuel, and any other changes to the
appliance operations that occur during pretest ignition period.
During the 15-minute period prior to the start of the test run, the
wood heater loading door shall not be open more than a total of 1
minute. Coal bed raking is the only adjustment allowed during this
period.
12.4.1.3 Coal Bed Weight. The appliance is to be loaded with the
test fuel charge when the coal bed weight is between 10 percent and
20 percent of the test fuel charge weight. Coals may be raked as
necessary to level the coal bed but may only be raked and stirred
once between 15 to 20 minutes prior to the addition of the test
fuel charge.
12.4.1.4 Storage. The Category III and IV test runs may be done
either with or without the thermal storage. If thermal storage is
used, the initial temperature of the storage must be 125 °F or
greater at the start of the test. The storage may be heated during
the pre-test burn cycle or it may be heated by external means. If
thermal storage is used, prior to the start of the test run, the
storage tank destratification pump, shown in Figure 1, shall be
operated until the total volume pumped exceeds 1.5 times the tank
volume and the difference between the temperature at the top and
bottom of the storage tank (TS1 and TS2) is less than 1 °F. These
two temperatures shall then be recorded to determine the starting
average tank temperature. The total volume pumped may be based on
the nominal flow rate of the destratification pump (See section
9.6). If the Category III and IV runs are done with storage, it is
recognized that during the last hour of the pre-burn cycle the
storage tank must be mixed to achieve a uniform starting
temperature and cannot receive heat from the boiler/heater during
this time. During this time period, the boiler/heater might cycle
or go into a steady reduced output mode. (Note - this would happen,
for example, in a Category IV run if the actual maximum output of
the boiler/heater exceed the manufacturer's rated output.) A second
storage tank may be used temporarily to enable the boiler/heater to
operate during this last hour of the pre-burn period as it will
during the test period. The temperature of this second storage tank
is not used in the calculations but the return water to the
boiler/heater (after mixing device if used) must be 125 °F or
greater.
12.4.2 Startup Procedure for Category I and II Test Runs,
“Cold-to-Cold.”
12.4.2.1 Initial Temperatures. This test shall be started with
both the boiler/heater and the storage at a minimum temperature of
125 °F. The boiler/heater maximum temperature at the start of this
test shall be 135 °F. The boiler/heater and storage may be heated
through a pre-burn or it may be heated by external means.
12.4.2.2 Firebox Condition at Test Start. Prior to the start of
this test remove all ash and charcoal from the combustion
chamber(s). The loading of the test fuel and kindling should follow
the manufacturer's recommendations, subject to the following
constraints: Up to 10 percent kindling and paper may be used which
is in addition to the fuel load. Further, up to 10 percent of the
fuel load (i.e., included in the 10 lb/ft 3) may be smaller
than the main fuel. This startup fuel shall still be larger than 2
inches.
12.4.2.3 Storage. The Category I and II test runs shall be done
with thermal storage. The initial temperature of the storage must
be 125 °F or greater at the start of the test. The storage may be
heated during the pre-test burn cycle or it may be heated by
external means. Prior to the start of the test run, the storage
tank destratification pump, shown in Figure 1, shall be operated
until the total volume pumped exceeds 1.5 times the tank volume and
the difference between the temperature at the top and bottom of the
storage tank (TS1 and TS2) is less than 1 °F. These two
temperatures shall then be recorded to determine the starting
average tank temperature. The total volume pumped may be based on
the nominal flow rate of the destratification pump (See section
9.6).
12.5 Test Runs. For all test runs, the return water temperature
to the hydronic heater must be equal to or greater than 120 °F
(this is lower than the initial tank temperature to allow for any
pipeline losses). Where the storage system is used, flow of water
from the boiler/heater shall be divided between the storage tank
and the heat exchanger such that the temperature change of the
circulating water across the heat exchanger shall be 30 ±5 °F,
averaged over the entire test run. This is typically adjusted using
the system valves.
Complete a test run in each heat output rate category, as
follows:
12.5.1 Test Run Start. For Category III and IV runs: Once the
appliance is operating normally and the pretest coal bed weight has
reached the target value per section 12.4.1, tare the scale and
load the full test charge into the appliance. Time for loading
shall not exceed 5 minutes. The actual weight of the test fuel
charge shall be measured and recorded within 30 minutes prior to
loading. Start all sampling systems.
For Category I and II runs: Once the appliance has reached the
starting temperature, tare the scale and load the full test charge,
including kindling into the appliance. The actual weight of the
test fuel charge shall be measured and recorded within 30 minutes
prior to loading. Light the fire following the manufacturer's
written normal startup procedure. Start all sampling systems.
12.5.1.1 Record all water temperatures, differential water
temperatures and water flow rates at time intervals of one minute
or less.
12.5.1.2 Record particulate emissions data per the requirements
of EPA Method 28WHH and the standards referenced therein.
12.5.1.3 Record data needed to determine overall efficiency
(SLM) per the requirements of CSA B415.1-10 (IBR, see § 60.17)
clauses 6.2.1, 6.2.2, 6.3, 8.5.7, 10.4.3(a), 10.4.3(f), and
13.7.9.3
12.5.1.3.1 Measure and record the test room air temperature in
accordance with the requirements of CSA B415.1-10 (IBR, see §
60.17), clauses 6.2.1, 8.5.7 and 10.4.3(g).
12.5.1.3.2 Measure and record the flue gas temperature in
accordance with the requirements of CSA B415.1-10 (IBR, see §
60.17), clauses 6.2.2, 8.5.7 and 10.4.3(f).
12.5.1.3.3 Determine and record the carbon monoxide (CO) and
carbon dioxide (CO2) concentrations in the flue gas in accordance
with CSA B415.1-10 (IBR, see § 60.17), clauses 6.3, 8.5.7 and
10.4.3(i) and (j).
12.5.1.3.4 Measure and record the test fuel weight per the
requirements of CSA B415.1-10 (IBR, see § 60.17), clauses 8.5.7 and
10.4.3(h).
12.5.1.3.5 Record the test run time per the requirements of CSA
B415.1-10 (IBR, see § 60.17), clause 10.4.3(a).
12.5.1.3.6 Record and document all settings and adjustments, if
any, made to the boiler/heater as recommended/required by
manufacturer's instruction manual for different combustion
conditions or heat loads. These may include temperature setpoints,
under and over-fire air adjustment, or other adjustments that could
be made by an operator to optimize or alter combustion. All such
settings shall be included in the report for each test run.
12.5.1.4 Monitor the average heat output rate on the load side
of the heat exchanger based on water temperatures and flow. If the
heat output rate over a 10 minute averaging period gets close to
the upper or lower limit of the target range (±5 percent), adjust
the water flow through the heat exchanger to compensate. Make
changes as infrequently as possible while maintaining the target
heat output rate. The first test run shall be conducted at the
Category IV heat output rate to validate that the appliance is
capable of producing the manufacturer's rated heat output
capacity.
12.5.2 Test Fuel Charge Adjustment. It is acceptable to adjust
the test fuel charge (i.e., reposition) once during a test
run if more than 60 percent of the initial test fuel charge weight
has been consumed and more than 10 minutes have elapsed without a
measurable (1 lb or 0.5 kg) weight change while the operating
control is in the demand mode. The time used to make this
adjustment shall be less than 60 seconds.
12.5.3 Test Run Completion. For the Category III and IV,
“hot-to-hot” test runs, the test run is completed when the
remaining weight of the test fuel charge is 0.0 lb (0.0 kg).
(WFuelBurned = Wfuel) End the test run when the scale
has indicated a test fuel charge weight of 0.0 lb (0.0 kg) or less
for 30 seconds.
For the Category I and II “cold-to-cold” test runs, the test run
is completed; and the end of a test is defined at the first
occurrence of any one of the following:
(a) The remaining weight of the test fuel charge is less than 1
percent of the total test fuel weight (WFuelBurned > 0.99
· Wfuel);
(b) The automatic control system on the boiler/heater switches
to an off mode. In this case, the boiler/heater fan (if used) is
typically stopped and all air flow dampers are closed by the
control system. Note that this off mode cannot be an “overheat” or
emergency shutdown which typically requires a manual reset; or
(c) If the boiler/heater does not have an automatic off mode:
After 90 percent of the fuel load has been consumed and the scale
has indicated a rate of change of the test fuel charge of less than
1.0 lb/hr for a period of 10 minutes or longer. Note - this is not
considered “stopped fuel combustion,” See section 12.5.6.1.
12.5.3.1 At the end of the test run, stop the particulate
sampling train and overall efficiency (SLM) measurements, and
record the run time, and all final measurement values.
12.5.3.2 At the end of the test run, continue to operate the
storage tank destratification pump until the total volume pumped
exceeds 1.5 times the tank volume. The maximum average of the top
and bottom temperatures measured after this time may be taken as
the average tank temperature at the end of the tests (TFSavg, See
section 13.1). The total volume pumped may be based on the nominal
flow rate of the destratification pump (See section 9.6).
12.5.3.3 For the Category I and II test runs, there is a need to
determine the energy content of the unburned fuel remaining in the
chamber if the remaining mass in the chamber is greater than 1
percent of the test fuel weight. Following the completion of the
test, as soon as safely practical, this remaining fuel is removed
from the chamber, separated from the remaining ash and weighed.
This separation could be implemented with a slotted “scoop” or
similar tool. A 1/4 inch opening size in the separation tool shall
be used to separate the ash and charcoal. This separated char is
assigned a heating value of 12,500 Btu/lb.
12.5.4 Heat Output Capacity Validation. The first test run must
produce a heat output rate that is within 10 percent of the
manufacturer's rated heat output capacity (Category IV) throughout
the test run and an average heat output rate within 5 percent of
the manufacturer's rated heat output capacity. If the appliance is
not capable of producing a heat output within these limits, the
manufacturer's rated heat output capacity is considered not
validated and testing is to be terminated. In such cases, the tests
may be restarted using a lower heat output capacity if requested by
the manufacturer. Alternatively, during the Category IV run, if the
rated output cannot be maintained for a 15 minute interval, the
manufacturer may elect to reduce the rated output to match the test
and complete the Category IV run on this basis. The target outputs
for Categories I, II, and III shall then be recalculated based on
this change in rated output capacity.
12.5.5 Additional Test Runs. Using the manufacturer's rated heat
output capacity as a basis, conduct a test for additional heat
output categories as specified in section 4.3. It is not required
to run these tests in any particular order.
12.5.6 Alternative Heat Output Rate for Category I. If an
appliance cannot be operated in the Category I heat output range
due to stopped combustion, two test runs shall be conducted at heat
output rates within Category II. When this is the case, the
weightings for the weighted averages indicated in section 14.1.15
shall be the average of the Category I and II weighting's and shall
be applied to both Category II results. Appliances that are not
capable of operation within Category II (<25 percent of maximum)
cannot be evaluated by this test method.
12.5.6.1 Stopped Fuel Combustion. Evidence that an appliance
cannot be operated at a Category I heat output rate due to stopped
fuel combustion shall include documentation of two or more attempts
to operate the appliance in heat output rate Category I and fuel
combustion has stopped prior to complete consumption of the test
fuel charge. Stopped fuel combustion is evidenced when an elapsed
time of 60 minutes or more has occurred without a measurable (1 lb
or 0.5 kg) weight change in the test fuel charge while the
appliance operating control is in the demand mode. Report the
evidence and the reasoning used to determine that a test in heat
output rate Category I cannot be achieved. For example, two
unsuccessful attempts to operate at an output rate of 10 percent of
the rated output capacity are not sufficient evidence that heat
output rate Category I cannot be achieved.
12.5.7 Appliance Overheating. Appliances with their associated
thermal storage shall be capable of operating in all heat output
categories without overheating to be rated by this test method.
Appliance overheating occurs when the rate of heat withdrawal from
the appliance is lower than the rate of heat production when the
unit control is in the idle mode. This condition results in the
water in the appliance continuing to increase in temperature well
above the upper limit setting of the operating control. Evidence of
overheating includes: 1 hour or more of appliance water temperature
increase above the upper temperature set-point of the operating
control, exceeding the temperature limit of a safety control device
(independent from the operating control - typically requires manual
reset), boiling water in a non-pressurized system or activation of
a pressure or temperature relief valve in a pressurized system.
12.5.8 Option to Eliminate Tests in Category II and III.
Following successful completion of a test run in Category I, the
manufacturer may eliminate the Category II and III tests. For the
purpose of calculating the annual averages for particulates and
efficiency, the values obtained in the Category I run shall be
assumed to apply also to Category II and Category III. It is
envisioned that this option would be applicable to systems which
have sufficient thermal storage such that the fuel load in the
Category I test can be completely consumed without the system
reaching its upper operating temperature limit. In this case, the
boiler/heater would likely be operating at maximum thermal output
during the entire test and this output rate may be higher than the
manufacturer's rated heat output capacity. The Category II and III
runs would then be the same as the Category I run. It may be
assumed that the particulate emission values and efficiency values
determined in the startup, steady-state, and end phases of Category
I are applicable in Categories II and III, for the purpose of
determining the annual averages in lb/mmBtu and g/MJ (See section
13). For the annual average in g/hr, the length of time for stored
heat to be drawn from thermal storage shall be determined for the
test load requirements of the respective category.
12.5.9 Modification to Measurement Procedure in EPA Method 28WHH
to Determine Emissions Separately During the Startup, Steady-State
and End Phases. With one of the two particulate sampling trains
used, filter changes shall be made at the end of the startup phase
and the steady-state phase (See section 3.0). This shall be done to
determine the particulate emission rate and particulate emission
index for the startup, steady-state, and end phases individually.
For this one train, the particulates measured during each of these
three phases shall be added together to also determine the
particulate emissions for the whole run.
12.5.10 Modification to Measurement Procedure in EPA Method
28WHH and the Standards Referenced therein on Averaging Period for
Determination of Efficiency by the Stack Loss Method. The methods
currently defined in Method 28WHH allow averaging over 10-minute
time periods for flue gas temperature, flue gas CO2, and flue gas
CO for the determination of the efficiency with the stack loss
method. However, under some cycling conditions the “on” period may
be short relative to this 10-minute period. For this reason, during
cycling operation the averaging period for these parameters may not
be longer than the burner on period divided by 10. The averaging
period need not be shorter than one minute. During the off period,
under cycling operation, averaging periods as specified in EPA
Method 28WHH and the standards referenced therein, may be used.
Where short averaging times are used, however, the averaging period
for fuel consumption may still be at 10 minutes. This average wood
consumption rate shall be applied to all of the smaller time
intervals included.
12.6 Additional Test Runs. The testing laboratory may conduct
more than one test run in each of the heat output categories
specified in section 4.3. If more than one test run is conducted at
a specified heat output rate, the results from at least two-thirds
of the test runs in that heat output rate category shall be used in
calculating the weighted average emission rate. The measurement
data and results of all test runs shall be reported regardless of
which values are used in calculating the weighted average emission
rate.
13.0 Calculation of Results 13.1 Nomenclature COs - Carbon monoxide
measured in the dilution tunnel at arbitrary time in ppm dry basis.
COg/min - Carbon monoxide emission rate in g/min. COT - Total
carbon monoxide emission for the full test run in grams. CO_1 -
Startup period carbon monoxide emissions in grams. CO_2 -
Steady-state period carbon monoxide emission in grams. CO_3 - End
period carbon monoxide emission in grams. ET - Total particulate
emissions for the full test run as determined per EPA Method 28WHH
and the standards referenced therein in grams. E1 - Startup period
particulate emissions in grams. E2 - Steady-state period
particulate emissions in grams. E3 - End period particulate
emissions in grams. E1_g/kg - Startup period particulate emission
index in grams per kg fuel. E2_g/kg - Steady-state period
particulate emission index in grams per kg fuel. E3_g/kg - End
period particulate emission index in grams per kg fuel. E1_g/hr -
Startup period particulate emission rate in grams per hour. E2_g/hr
- Steady-state period particulate emission rate in grams per hour.
E3_g/hr - End period particulate emission rate in grams per hour.
Eg/MJ - Emission rate in grams per MJ of heat output. Elb/mmBtu
output - Emissions rate in pounds per million Btu of heat output.
Eg/kg - Emissions factor in grams per kilogram of dry fuel burned.
Eg/hr - Emission factor in grams per hour. HHV - Higher heating
value of fuel = 8600 Btu/lb (19.990 MJ/kg). LHV - Lower heating
value of fuel = 7988 Btu/lb (18.567 MJ/kg). ΔT - Temperature
difference between cooling water entering and exiting the heat
exchanger. Qout - Total heat output in Btu (MJ). Qin - Total heat
input available in test fuel charge in Btu's (MJ). Qstd -
Volumetric flow rate in dilution tunnel in dscfm. M - Mass flow
rate of water in lb/min (kg/min). Vi - Volume of water indicated by
a totalizing flow meter at the ith reading in gallons (liters). Vf
- Volumetric flow rate of water in heat exchange system in gallons
per minute (liters/min). Θ - Total length of burn period in hours
(Θ1 + Θ2 + Θ3). Θ1 - Length of time of the startup period in hours.
Θ2 - Length of time of the steady-state period in hours. Θ3 -
Length of time of the end period in hours. Θ4 - Length of time for
stored heat to be used following a burn period in hours. ti - Data
sampling interval in minutes. ηdel - Delivered heating efficiency
in percent. Fi - Weighting factor for heat output category i. (See
Table 2.) T1 - Temperature of water at the inlet on the supply side
of the heat exchanger, °F. T2 - Temperature of the water at the
outlet on the supply side of the heat exchanger, °F. T3 -
Temperature of cooling water at the inlet to the load side of the
heat exchanger, °F. T4 - Temperature of cooling water at the outlet
of the load side of the heat exchanger, °F. T5 - Temperature of the
hot water supply as it leaves the boiler/heater, °F. T6 -
Temperature of return water as it enters the boiler/heater, °F. T7
- Temperature in the boiler/heater optional destratification loop
at the top of the boiler/heater, °F. T8 - Temperature in the
boiler/heater optional destratification loop at the bottom of the
boiler/heater, °F. TIavg - Average temperature of the appliance and
water at start of the test. TFavg - Average
temperature of the appliance and water at the end of the test.
TIS1 -
Temperature at the inlet to the storage system at the start of the
test. TIS2 - Temperature at the outlet from the storage system at
the start of the test. TFS1 - Temperature at the inlet to the
storage system at the end of the test. TFS2 - Temperature at the
outlet from the storage system at the end of the test. TISavg -
Average temperature of the storage system at the start of the test.
TFSavg -
Average temperature of the storage system at the end of the test.
MC - Fuel
moisture content in percent dry basis. σ - Density of water in
pounds per gallon. σInitial - Density of water in the boiler/heater
system at the start of the test in pounds per gallons.
σboiler/heater - Density of water in the boiler/heater system at an
arbitrary time during the test in pounds per gallon. Cp - Specific
heat of water in Btu/lb, °F. Csteel - Specific heat of steel (0.1
Btu/lb, °F). Vboiler/heater - total volume of water in the
boiler/heater system on the weight scale in gallons. Wfuel - Fuel
charge weight, as-fired or “wet”, in pounds (kg). Wfuel_1 - Fuel
consumed during the startup period in pounds (kg). Wfuel_2 - Fuel
consumed during the steady state period in pounds (kg). Wfuel_3 -
Fuel consumed during the end period in pounds (kg). WFuelBurned -
Weight of fuel that has been burned from the start of the test to
an arbitrary time, including the needed correction for the change
in density and weight of the water in the boiler/heater system on
the scale in pounds (kg). WRemainingFuel - Weight of unburned fuel
separated from the ash at the end of a test. Useful only for
Category I and Category II tests. Wapp - Weight of empty appliance
in pounds (kg). Wwat - Weight of water in supply side of the system
in pounds (kg). WScaleInitial - Weight reading on the scale at the
start of the test, just after the test load has been added in
pounds (kg). WScale - Reading of the weight scale at an arbitrary
time during the test run in pounds (kg). WStorageTank - Weight of
the storage tank empty in pounds (kg). WWaterStorage - Weight of
the water in the storage tank at TISavg in pounds (kg).
13.2 After the test is completed, determine the particulate
emissions ET in accordance with EPA Method 28WHH and the standards
referenced therein.
13.3 Determination of the weight of fuel that has been burned at
an arbitrary time.
For the purpose of tracking the consumption of the test fuel
load during a test run the following may be used to calculate the
weight of fuel that burned since the start of the test:
Water
density, σ, is calculated using Equation 12. 13.4 Determine Average
Fuel Load Moisture Content. 13.5 Determine
Heat Input.
13.5.1 Correction to Qin for the Category I and II tests, where
there is greater than 1 percent of the test fuel charge in the
chamber at the end of the test period.
13.6 Determine Heat Output, Efficiency, and Emissions.
13.6.1 Determine heat output as:
Qout = Σ [Heat output determined for each sampling time
interval] + Change in heat stored in the appliance + Change in heat
in storage tank.
Note:
The subscript (i) indicates the parameter value for sampling
time interval ti.Mi = Mass flow rate = gal/min × density of water
(lb/gal) = lb/min.
Csteel =
0.1 Btu/lb, -° F. Note:
Vi is the total water volume at the end of interval i and Vi-1
is the total water volume at the beginning of the time interval.
This calculation is necessary when a totalizing type water meter is
used.
13.6.2 Determine Heat Output Rate Over Burn Period (Θ1 + Θ2 +
Θ3) as:
13.6.3 Determine Emission Rates and Emission Factors as:
If thermal storage is not used in a Category III or IV run, then
Θ4 = 0.
E1_g/kg = E1/(Wfuel_1/(1 + MC/100)), g/dry kg.
E2_g/kg = E2/(Wfuel_2/(1 + MC/100)), g/dry kg.
E3_g/kg = E3/(Wfuel_3/(1 + MC/100)), g/dry kg.
E1_g/hr = E1/Θ1, g/hr.
E2_g/hr = E2/Θ2, g/hr.
E3_g/hr = E3/Θ3, g/hr.
13.6.4 Determine delivered efficiency as:
13.6.5 Determine ηSLM - Overall Efficiency, also known as Stack
Loss Efficiency, using stack loss method (SLM).
For determination of the average overall thermal efficiency
(ηSLM) for the test run, use the data collected over the full test
run and the calculations in accordance with CSA B415.1-10 (IBR, see
§ 60.17), clause 13.7 except for 13.7.2(e), (f), (g), and (h), use
the following average fuel properties for oak: %C = 50.0, %H = 6.6,
%O = 43.2, %Ash = 0.2.
13.6.5.1 Whenever the CSA B415.1-10 (IBR, see § 60.17) overall
efficiency is found to be lower than the overall efficiency based
on load side measurements, as determined by Eq. 22 of this method,
section 14.1.7 of the test report must include a discussion of the
reasons for this result. For a test where the CSA B415.1-10 overall
efficiency SLM is less than 2 percentage points lower than the
overall efficiency based on load side measurements, the efficiency
based on load side measurements shall be considered invalid. [Note
on the rationale for the 2 percentage points limit. The SLM method
does not include boiler/heater jacket losses and, for this reason,
should provide an efficiency which is actually higher than the
efficiency based on the energy input and output measurements or
“delivered efficiency.” A delivered efficiency that is higher than
the efficiency based on the SLM could be considered suspect. A
delivered efficiency greater than 2 percentage points higher than
the efficiency based on the SLM, then, clearly indicates a
measurement error.]
13.6.6 Carbon Monoxide Emissions
For each minute of the test period, the carbon monoxide emission
rate shall be calculated as:
Total CO emissions for each of the three test periods (CO_1,
CO_2, CO_3) shall be calculated as the sum of the emission rates
for each of the 1-minute intervals. Total CO emission for the test
run, COT, shall be calculated as the sum of CO_1, CO_2, and
CO_3.
13.7 Weighted Average Emissions and Efficiency.
13.7.1 Determine the weighted average emission rate and
delivered efficiency from the individual tests in the specified
heat output categories. The weighting factors (Fi) are derived from
an analysis of ASHRAE bin data which provides details of normal
building heating requirements in terms of percent of design
capacity and time in a particular capacity range - or “bin” - over
the course of a heating season. The values used in this method
represent an average of data from several cities located in the
northern United States.
If, as discussed in section 12.5.8, the option to eliminate
tests in Category II and III is elected, the values of efficiency
and particulate emission rate as measured in Category I, shall be
assigned also to Category II and III for the purpose of determining
the annual averages.
14.0 Report
14.1.1 The report shall include the following:
14.1.2 Name and location of the laboratory conducting the
test.
14.1.3 A description of the appliance tested and its condition,
date of receipt and dates of tests.
14.1.4 A description of the minimum amount of external thermal
storage that is required for use with this system. This shall be
specified both in terms of volume in gallons and stored energy
content in Btu with a storage temperature ranging from 125 °F to
the manufacturer's specified setpoint temperature.
14.1.5 A statement that the test results apply only to the
specific appliance tested.
14.1.6 A statement that the test report shall not be reproduced
except in full, without the written approval of the laboratory.
14.1.7 A description of the test procedures and test equipment
including a schematic or other drawing showing the location of all
required test equipment. Also, a description of test fuel sourcing,
handling and storage practices shall be included.
14.1.8 Details of deviations from, additions to or exclusions
from the test method, and their data quality implications on the
test results (if any), as well as information on specific test
conditions, such as environmental conditions.
14.1.9 A list of participants and their roles and observers
present for the tests.
14.1.10 Data and drawings indicating the fire box size and
location of the fuel charge.
14.1.11 Drawings and calculations used to determine firebox
volume.
14.1.12 Information for each test run fuel charge including
piece size, moisture content and weight.
14.1.13 All required data and applicable blanks for each test
run shall be provided in spreadsheet format both in the printed
report and in a computer file such that the data can be easily
analyzed and calculations easily verified. Formulas used for all
calculations shall be accessible for review.
14.1.14 For each test run, Θ1,Θ2, Θ3, the total CO and
particulate emission for each of these three periods, and Θ4.
14.1.15 Calculated results for delivered efficiency at each heat
output rate and the weighted average emissions reported as total
emissions in grams, pounds per mm Btu of delivered heat, grams per
MJ of delivered heat, grams per kilogram of dry fuel and grams per
hour. Results shall be reported for each heat output category and
the weighted average.
14.1.16 Tables 1A, 1B, 1C, 1D, 1E and Table 2 must be used for
presentation of results in test reports.
14.1.17 A statement of the estimated uncertainty of measurement
of the emissions and efficiency test results.
14.1.18 A plot of CO emission rate in grams/minute vs. time,
based on 1 minute averages, for the entire test period, for each
run.
14.1.19 A plot of estimated boiler/heater energy release rate in
Btu/hr based on 10 minute averages, for the entire test period, for
each run. This will be calculated from the fuel used, the wood
heating value and moisture content, and the SLM efficiency during
each 10 minute period.
14.1.20 Raw data, calibration records, and other relevant
documentation shall be retained by the laboratory for a minimum of
7 years.
15.0 Precision and Bias
15.1 Precision - It is not possible to specify the precision of
the procedure in this test method because the appliance operation
and fueling protocols and the appliances themselves produce
variable amounts of emissions and cannot be used to determine
reproducibility or repeatability of this test method.
15.2 Bias - No definitive information can be presented on the
bias of the procedure in this test method for measuring solid fuel
burning hydronic heater emissions because no material having an
accepted reference value is available.
Method 29 -
Determination of Metals Emissions From Stationary Sources Note:
This method does not include all of the specifications
(e.g., equipment and supplies) and procedures (e.g.,
sampling and analytical) essential to its performance. Some
material is incorporated by reference from other methods in this
part. Therefore, to obtain reliable results, persons using this
method should have a thorough knowledge of at least the following
additional test methods: Method 5 and Method 12.
1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Antimony (Sb)
7440-36-0
Arsenic (As)
7440-38-2
Barium (Ba)
7440-39-3
Beryllium
(Be)
7440-41-7
Cadmium (Cd)
7440-43-9
Chromium (Cr)
7440-47-3
Cobalt (Co)
7440-48-4
Copper (Cu)
7440-50-8
Lead (Pb)
7439-92-1
Manganese
(Mn)
7439-96-5
Mercury (Hg)
7439-97-6
Nickel (Ni)
7440-02-0
Phosphorus
(P)
7723-14-0
Selenium (Se)
7782-49-2
Silver (Ag)
7440-22-4
Thallium (Tl)
7440-28-0
Zinc (Zn)
7440-66-6
1.2 Applicability. This method is applicable to the
determination of metals emissions from stationary sources. This
method may be used to determine particulate emissions in addition
to the metals emissions if the prescribed procedures and
precautions are followed.
1.2.1 Hg emissions can be measured, alternatively, using EPA
Method 101A of Appendix B, 40 CFR Part 61. Method 101-A measures
only Hg but it can be of special interest to sources which need to
measure both Hg and Mn emissions.
2.0 Summary of Method
2.1 Principle. A stack sample is withdrawn isokinetically from
the source, particulate emissions are collected in the probe and on
a heated filter, and gaseous emissions are then collected in an
aqueous acidic solution of hydrogen peroxide (analyzed for all
metals including Hg) and an aqueous acidic solution of potassium
permanganate (analyzed only for Hg). The recovered samples are
digested, and appropriate fractions are analyzed for Hg by cold
vapor atomic absorption spectroscopy (CVAAS) and for Sb, As, Ba,
Be, Cd, Cr, Co, Cu, Pb, Mn, Ni, P, Se, Ag, Tl, and Zn by
inductively coupled argon plasma emission spectroscopy (ICAP) or
atomic absorption spectroscopy (AAS). Graphite furnace atomic
absorption spectroscopy (GFAAS) is used for analysis of Sb, As, Cd,
Co, Pb, Se, and Tl if these elements require greater analytical
sensitivity than can be obtained by ICAP. If one so chooses, AAS
may be used for analysis of all listed metals if the resulting
in-stack method detection limits meet the goal of the testing
program. Similarly, inductively coupled plasma-mass spectroscopy
(ICP-MS) may be used for analysis of Sb, As, Ba, Be, Cd, Cr, Co,
Cu, Pb, Mn, Ni, Ag, Tl and Zn.
3.0 Definitions [Reserved] 4.0 Interferences
4.1 Iron (Fe) can be a spectral interference during the analysis
of As, Cr, and Cd by ICAP. Aluminum (Al) can be a spectral
interference during the analysis of As and Pb by ICAP. Generally,
these interferences can be reduced by diluting the analytical
sample, but such dilution raises the in-stack detection limits.
Background and overlap corrections may be used to adjust for
spectral interferences. Refer to Method 6010 of Reference 2 in
section 16.0 or the other analytical methods used for details on
potential interferences to this method. For all GFAAS analyses, use
matrix modifiers to limit interferences, and matrix match all
standards.
5.0 Safety
5.1 Disclaimer. This method may involve hazardous materials,
operations, and equipment. This test method may not address all of
the safety problems associated with its use. It is the
responsibility of the user of this test method to establish
appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to performing this
test method.
5.2 Corrosive Reagents. The following reagents are hazardous.
Personal protective equipment and safe procedures are useful in
preventing chemical splashes. If contact occurs, immediately flush
with copious amounts of water at least 15 minutes. Remove clothing
under shower and decontaminate. Treat residual chemical burn as
thermal burn.
5.2.1 Nitric Acid (HNO3). Highly corrosive to eyes, skin, nose,
and lungs. Vapors cause bronchitis, pneumonia, or edema of lungs.
Reaction to inhalation may be delayed as long as 30 hours and still
be fatal. Provide ventilation to limit exposure. Strong oxidizer.
Hazardous reaction may occur with organic materials such as
solvents.
5.2.2 Sulfuric Acid (H2SO4). Rapidly destructive to body tissue.
Will cause third degree burns. Eye damage may result in blindness.
Inhalation may be fatal from spasm of the larynx, usually within 30
minutes. May cause lung tissue damage with edema. 1 mg/m 3 for 8
hours will cause lung damage or, in higher concentrations, death.
Provide ventilation to limit inhalation. Reacts violently with
metals and organics.
5.2.3 Hydrochloric Acid (HC1). Highly corrosive liquid with
toxic vapors. Vapors are highly irritating to eyes, skin, nose, and
lungs, causing severe damage. May cause bronchitis, pneumonia, or
edema of lungs. Exposure to concentrations of 0.13 to 0.2 percent
can be lethal to humans in a few minutes. Provide ventilation to
limit exposure. Reacts with metals, producing hydrogen gas.
5.2.4 Hydrofluoric Acid (HF). Highly corrosive to eyes, skin,
nose, throat, and lungs. Reaction to exposure may be delayed by 24
hours or more. Provide ventilation to limit exposure.
5.2.5 Hydrogen Peroxide (H2O2). Irritating to eyes, skin, nose,
and lungs. 30% H2O2 is a strong oxidizing agent. Avoid contact with
skin, eyes, and combustible material. Wear gloves when
handling.
5.2.7 Potassium Persulfate. Strong oxidizer. Avoid bodily
contact with. Keep containers well closed and in a cool place.
5.3 Reaction Pressure. Due to the potential reaction of the
potassium permanganate with the acid, there could be pressure
buildup in the acidic KMnO4 absorbing solution storage bottle.
Therefore these bottles shall not be fully filled and shall be
vented to relieve excess pressure and prevent explosion potentials.
Venting is required, but not in a manner that will allow
contamination of the solution. A No. 70-72 hole drilled in the
container cap and Teflon liner has been used.
6.0 Equipment and Supplies
6.1 Sampling. A schematic of the sampling train is shown in
Figure 29-1. It has general similarities to the Method 5 train.
6.1.1 Probe Nozzle (Probe Tip) and Borosilicate or Quartz Glass
Probe Liner. Same as Method 5, sections 6.1.1.1 and 6.1.1.2, except
that glass nozzles are required unless alternate tips are
constructed of materials that are free from contamination and will
not interfere with the sample. If a probe tip other than glass is
used, no correction to the sample test results to compensate for
the nozzle's effect on the sample is allowed. Probe fittings of
plastic such as Teflon, polypropylene, etc. are recommended instead
of metal fittings to prevent contamination. If one chooses to do
so, a single glass piece consisting of a combined probe tip and
probe liner may be used.
6.1.2 Pitot Tube and Differential Pressure Gauge. Same as Method
2, sections 6.1 and 6.2, respectively.
6.1.3 Filter Holder. Glass, same as Method 5, section 6.1.1.5,
except use a Teflon filter support or other non-metallic,
non-contaminating support in place of the glass frit.
6.1.4 Filter Heating System. Same as Method 5, section
6.1.1.6.
6.1.5 Condenser. Use the following system for condensing and
collecting gaseous metals and determining the moisture content of
the stack gas. The condensing system shall consist of four to seven
impingers connected in series with leak-free ground glass fittings
or other leak-free, non-contaminating fittings. Use the first
impinger as a moisture trap. The second impinger (which is the
first HNO3/H2O2 impinger) shall be identical to the first impinger
in Method 5. The third impinger (which is the second HNO3/H2O2
impinger) shall be a Greenburg Smith impinger with the standard tip
as described for the second impinger in Method 5, section 6.1.1.8.
The fourth (empty) impinger and the fifth and sixth (both acidified
KMnO4) impingers are the same as the first impinger in Method 5.
Place a temperature sensor capable of measuring to within 1 °C (2
°F) at the outlet of the last impinger. If no Hg analysis is
planned, then the fourth, fifth, and sixth impingers are not
used.
6.1.6 Metering System, Barometer, and Gas Density Determination
Equipment. Same as Method 5, sections 6.1.1.9, 6.1.2, and 6.1.3,
respectively.
6.1.7 Teflon Tape. For capping openings and sealing connections,
if necessary, on the sampling train.
6.2 Sample Recovery. Same as Method 5, sections 6.2.1 through
6.2.8 (Probe-Liner and Probe-Nozzle Brushes or Swabs, Wash Bottles,
Sample Storage Containers, Petri Dishes, Glass Graduated Cylinder,
Plastic Storage Containers, Funnel and Rubber Policeman, and Glass
Funnel), respectively, with the following exceptions and
additions:
6.2.1 Non-metallic Probe-Liner and Probe-Nozzle Brushes or
Swabs. Use non-metallic probe-liner and probe-nozzle brushes or
swabs for quantitative recovery of materials collected in the
front-half of the sampling train.
6.2.2 Sample Storage Containers. Use glass bottles (see section
8.1 of this Method) with Teflon-lined caps that are non-reactive to
the oxidizing solutions, with capacities of 1000- and 500-ml, for
storage of acidified KMnO4 - containing samples and blanks. Glass
or polyethylene bottles may be used for other sample types.
6.2.3 Graduated Cylinder. Glass or equivalent.
6.2.4 Funnel. Glass or equivalent.
6.2.5 Labels. For identifying samples.
6.2.6 Polypropylene Tweezers and/or Plastic Gloves. For recovery
of the filter from the sampling train filter holder.
6.3 Sample Preparation and Analysis.
6.3.1 Volumetric Flasks, 100-ml, 250-ml, and 1000-ml. For
preparation of standards and sample dilutions.
6.3.2 Graduated Cylinders. For preparation of reagents.
6.3.3 Parr Bombs or Microwave Pressure Relief Vessels with
Capping Station (CEM Corporation model or equivalent). For sample
digestion.
6.3.4 Beakers and Watch Glasses. 250-ml beakers, with watch
glass covers, for sample digestion.
6.3.5 Ring Stands and Clamps. For securing equipment such as
filtration apparatus.
6.3.6 Filter Funnels. For holding filter paper.
6.3.7 Disposable Pasteur Pipets and Bulbs.
6.3.8 Volumetric Pipets.
6.3.9 Analytical Balance. Accurate to within 0.1 mg.
6.3.10 Microwave or Conventional Oven. For heating samples at
fixed power levels or temperatures, respectively.
6.3.11 Hot Plates.
6.3.12 Atomic Absorption Spectrometer (AAS). Equipped with a
background corrector.
6.3.12.1 Graphite Furnace Attachment. With Sb, As, Cd, Co, Pb,
Se, and Tl hollow cathode lamps (HCLs) or electrodeless discharge
lamps (EDLs). Same as Reference 2 in section 16.0. Methods 7041
(Sb), 7060 (As), 7131 (Cd), 7201 (Co), 7421 (Pb), 7740 (Se), and
7841 (Tl).
6.3.12.2 Cold Vapor Mercury Attachment. With a mercury HCL or
EDL, an air recirculation pump, a quartz cell, an aerator
apparatus, and a heat lamp or desiccator tube. The heat lamp shall
be capable of raising the temperature at the quartz cell by 10 °C
above ambient, so that no condensation forms on the wall of the
quartz cell. Same as Method 7470 in Reference 2 in section 16.0.
See note 2: section 11.1.3 for other acceptable approaches for
analysis of Hg in which analytical detection limits of 0.002 ng/ml
were obtained.
6.3.13 Inductively Coupled Argon Plasma Spectrometer. With
either a direct or sequential reader and an alumina torch. Same as
EPA Method 6010 in Reference 2 in section 16.0.
Same as EPA Method 6020 in Reference 2 in section 16.0.
7.0 Reagents and Standards
7.1 Unless otherwise indicated, it is intended that all reagents
conform to the specifications established by the Committee on
Analytical Reagents of the American Chemical Society, where such
specifications are available. Otherwise, use the best available
grade.
7.2 Sampling Reagents.
7.2.1 Sample Filters. Without organic binders. The filters shall
contain less than 1.3 µg/in. 2 of each of the metals to be
measured. Analytical results provided by filter manufacturers
stating metals content of the filters are acceptable. However, if
no such results are available, analyze filter blanks for each
target metal prior to emission testing. Quartz fiber filters
meeting these requirements are recommended. However, if glass fiber
filters become available which meet these requirements, they may be
used. Filter efficiencies and unreactiveness to sulfur dioxide
(SO2) or sulfur trioxide (SO3) shall be as described in section
7.1.1 of Method 5.
7.2.2 Water. To conform to ASTM Specification D1193-77 or 91,
Type II (incorporated by reference - see § 60.17). If necessary,
analyze the water for all target metals prior to field use. All
target metals should be less than 1 ng/ml.
7.2.3 HNO3, Concentrated. Baker Instra-analyzed or
equivalent.
7.2.4 HCl, Concentrated. Baker Instra-analyzed or
equivalent.
7.2.5 H2O2, 30 Percent (V/V).
7.2.6 KMnO4.
7.2.7 H2SO4, Concentrated.
7.2.8 Silica Gel and Crushed Ice. Same as Method 5, sections
7.1.2 and 7.1.4, respectively.
7.3 Pretest Preparation of Sampling Reagents.
7.3.1 HNO3/H2O2 Absorbing Solution, 5 Percent HNO3/10 Percent
H2O2. Add carefully with stirring 50 ml of concentrated HNO3 to a
1000-ml volumetric flask containing approximately 500 ml of water,
and then add carefully with stirring 333 ml of 30 percent H2O2.
Dilute to volume with water. Mix well. This reagent shall contain
less than 2 ng/ml of each target metal.
7.3.2 Acidic KMnO4 Absorbing Solution, 4 Percent KMnO4 (W/V), 10
Percent H2SO4 (V/V). Prepare fresh daily. Mix carefully, with
stirring, 100 ml of concentrated H2SO4 into approximately 800 ml of
water, and add water with stirring to make a volume of 1 liter:
this solution is 10 percent H2SO4 (V/V). Dissolve, with stirring,
40 g of KMnO4 into 10 percent H2SO4 (V/V) and add 10 percent H2SO4
(V/V) with stirring to make a volume of 1 liter. Prepare and store
in glass bottles to prevent degradation. This reagent shall contain
less than 2 ng/ml of Hg.
Precaution: To prevent autocatalytic decomposition of the
permanganate solution, filter the solution through Whatman 541
filter paper.
7.3.3 HNO3, 0.1 N. Add with stirring 6.3 ml of concentrated HNO3
(70 percent) to a flask containing approximately 900 ml of water.
Dilute to 1000 ml with water. Mix well. This reagent shall contain
less than 2 ng/ml of each target metal.
7.3.4 HCl, 8 N. Carefully add with stirring 690 ml of
concentrated HCl to a flask containing 250 ml of water. Dilute to
1000 ml with water. Mix well. This reagent shall contain less than
2 ng/ml of Hg.
7.4 Glassware Cleaning Reagents.
7.4.1 HNO3, Concentrated. Fisher ACS grade or equivalent.
7.4.2 Water. To conform to ASTM Specifications D1193, Type
II.
7.4.3 HNO3, 10 Percent (V/V). Add with stirring 500 ml of
concentrated HNO3 to a flask containing approximately 4000 ml of
water. Dilute to 5000 ml with water. Mix well. This reagent shall
contain less than 2 ng/ml of each target metal.
7.5 Sample Digestion and Analysis Reagents. The metals
standards, except Hg, may also be made from solid chemicals as
described in Reference 3 in section 16.0. Refer to References 1, 2,
or 5 in section 16.0 for additional information on Hg standards.
The 1000 µg/ml Hg stock solution standard may be made according to
section 7.2.7 of Method 101A.
7.5.1 HCl, Concentrated.
7.5.2 HF, Concentrated.
7.5.3 HNO3, Concentrated. Baker Instra-analyzed or
equivalent.
7.5.4 HNO3, 50 Percent (V/V). Add with stirring 125 ml of
concentrated HNO3 to 100 ml of water. Dilute to 250 ml with water.
Mix well. This reagent shall contain less than 2 ng/ml of each
target metal.
7.5.5 HNO3, 5 Percent (V/V). Add with stirring 50 ml of
concentrated HNO3 to 800 ml of water. Dilute to 1000 ml with water.
Mix well. This reagent shall contain less than 2 ng/ml of each
target metal.
7.5.6 Water. To conform to ASTM Specifications D1193, Type
II.
7.5.7 Hydroxylamine Hydrochloride and Sodium Chloride Solution.
See Reference 2 In section 16.0 for preparation.
7.5.8 Stannous Chloride. See Reference 2 in section 16.0 for
preparation.
7.5.9 KMnO4, 5 Percent (W/V). See Reference 2 in section 16.0
for preparation.
7.5.10 H2SO4, Concentrated.
7.5.11 Potassium Persulfate, 5 Percent (W/V). See Reference 2 in
section 16.0 for preparation.
7.5.12 Nickel Nitrate, Ni(N03) 2 6H20.
7.5.13 Lanthanum Oxide, La203.
7.5.14 Hg Standard (AAS Grade), 1000 µg/ml.
7.5.15 Pb Standard (AAS Grade), 1000 µg/ml.
7.5.16 As Standard (AAS Grade), 1000 µg/ml.
7.5.17 Cd Standard (AAS Grade), 1000 µg/ml.
7.5.18 Cr Standard (AAS Grade), 1000 µg/ml.
7.5.19 Sb Standard (AAS Grade), 1000 µg/ml.
7.5.20 Ba Standard (AAS Grade), 1000 µg/ml.
7.5.21 Be Standard (AAS Grade), 1000 µg/ml.
7.5.22 Co Standard (AAS Grade), 1000 µg/ml.
7.5.23 Cu Standard (AAS Grade), 1000 µg/ml.
7.5.24 Mn Standard (AAS Grade), 1000 µg/ml.
7.5.25 Ni Standard (AAS Grade), 1000 µg/ml.
7.5.26 P Standard (AAS Grade), 1000 µg/ml.
7.5.27 Se Standard (AAS Grade), 1000 µg/ml.
7.5.28 Ag Standard (AAS Grade), 1000 µg/ml.
7.5.29 Tl Standard (AAS Grade), 1000 µg/ml.
7.5.30 Zn Standard (AAS Grade), 1000 µg/ml.
7.5.31 Al Standard (AAS Grade), 1000 µg/ml.
7.5.32 Fe Standard (AAS Grade), 1000 µg/ml.
7.5.33 Hg Standards and Quality Control Samples. Prepare fresh
weekly a 10 µg/ml intermediate Hg standard by adding 5 ml of 1000
µg/ml Hg stock solution prepared according to Method 101A to a
500-ml volumetric flask; dilute with stirring to 500 ml by first
carefully adding 20 ml of 15 percent HNO3 and then adding water to
the 500-ml volume. Mix well. Prepare a 200 ng/ml working Hg
standard solution fresh daily: add 5 ml of the 10 µg/ml
intermediate standard to a 250-ml volumetric flask, and dilute to
250 ml with 5 ml of 4 percent KMnO4, 5 ml of 15 percent HNO3, and
then water. Mix well. Use at least five separate aliquots of the
working Hg standard solution and a blank to prepare the standard
curve. These aliquots and blank shall contain 0.0, 1.0, 2.0, 3.0,
4.0, and 5.0 ml of the working standard solution containing 0, 200,
400, 600, 800, and 1000 ng Hg, respectively. Prepare quality
control samples by making a separate 10 µg/ml standard and diluting
until in the calibration range.
7.5.34 ICAP Standards and Quality Control Samples. Calibration
standards for ICAP analysis can be combined into four different
mixed standard solutions as follows:
Mixed Standard Solutions for ICAP
Analysis
Solution
Elements
I
As, Be, Cd, Mn, Pb, Se,
Zn.
II
Ba, Co, Cu, Fe.
III
Al, Cr, Ni.
IV
Ag, P, Sb, Tl.
Prepare these standards by combining and diluting the
appropriate volumes of the 1000 µg/ml solutions with 5 percent
HNO3. A minimum of one standard and a blank can be used to form
each calibration curve. However, prepare a separate quality control
sample spiked with known amounts of the target metals in quantities
in the mid-range of the calibration curve. Suggested standard
levels are 25 µg/ml for Al, Cr and Pb, 15 µg/ml for Fe, and 10
µg/ml for the remaining elements. Prepare any standards containing
less than 1 µg/ml of metal on a daily basis. Standards containing
greater than 1 µg/ml of metal should be stable for a minimum of 1
to 2 weeks. For ICP-MS, follow Method 6020 in EPA Publication
SW-846 Third Edition (November 1986) including updates I, II, IIA,
IIB and III, as incorporated by reference in § 60.17(i).
7.5.35 GFAAS Standards. Sb, As, Cd, Co, Pb, Se, and Tl. Prepare
a 10 µg/ml standard by adding 1 ml of 1000 µg/ml standard to a
100-ml volumetric flask. Dilute with stirring to 100 ml with 10
percent HNO3. For GFAAS, matrix match the standards. Prepare a 100
ng/ml standard by adding 1 ml of the 10 µg/ml standard to a 100-ml
volumetric flask, and dilute to 100 ml with the appropriate matrix
solution. Prepare other standards by diluting the 100 ng/ml
standards. Use at least five standards to make up the standard
curve. Suggested levels are 0, 10, 50, 75, and 100 ng/ml. Prepare
quality control samples by making a separate 10 µg/ml standard and
diluting until it is in the range of the samples. Prepare any
standards containing less than 1 µg/ml of metal on a daily basis.
Standards containing greater than 1 µg/ml of metal should be stable
for a minimum of 1 to 2 weeks.
7.5.36 Matrix Modifiers.
7.5.36.1 Nickel Nitrate, 1 Percent (V/V). Dissolve 4.956 g of
Ni(N03)2·6H20 or other nickel compound suitable for preparation of
this matrix modifier in approximately 50 ml of water in a 100-ml
volumetric flask. Dilute to 100 ml with water.
7.5.36.2 Nickel Nitrate, 0.1 Percent (V/V). Dilute 10 ml of 1
percent nickel nitrate solution to 100 ml with water. Inject an
equal amount of sample and this modifier into the graphite furnace
during GFAAS analysis for As.
7.5.36.3 Lanthanum. Carefully dissolve 0.5864 g of La203 in 10
ml of concentrated HN03, and dilute the solution by adding it with
stirring to approximately 50 ml of water. Dilute to 100 ml with
water, and mix well. Inject an equal amount of sample and this
modifier into the graphite furnace during GFAAS analysis for
Pb.
7.5.37 Whatman 40 and 541 Filter Papers (or equivalent). For
filtration of digested samples.
8.0 Sample Collection, Preservation, Transport, and Storage
8.1 Sampling. The complexity of this method is such that, to
obtain reliable results, both testers and analysts must be trained
and experienced with the test procedures, including source
sampling; reagent preparation and handling; sample handling; safety
equipment and procedures; analytical calculations; reporting; and
the specific procedural descriptions throughout this method.
8.1.1 Pretest Preparation. Follow the same general procedure
given in Method 5, section 8.1, except that, unless particulate
emissions are to be determined, the filter need not be desiccated
or weighed. First, rinse all sampling train glassware with hot tap
water and then wash in hot soapy water. Next, rinse glassware three
times with tap water, followed by three additional rinses with
water. Then soak all glassware in a 10 percent (V/V) nitric acid
solution for a minimum of 4 hours, rinse three times with water,
rinse a final time with acetone, and allow to air dry. Cover all
glassware openings where contamination can occur until the sampling
train is assembled for sampling.
8.1.2 Preliminary Determinations. Same as Method 5, section
8.1.2.
8.1.3 Preparation of Sampling Train.
8.1.3.1 Set up the sampling train as shown in Figure 29-1.
Follow the same general procedures given in Method 5, section 8.3,
except place 100 ml of the HNO3/H2O2 solution (Section 7.3.1 of
this method) in each of the second and third impingers as shown in
Figure 29-1. Place 100 ml of the acidic KMnO4 absorbing solution
(Section 7.3.2 of this method) in each of the fifth and sixth
impingers as shown in Figure 29-1, and transfer approximately 200
to 300 g of pre-weighed silica gel from its container to the last
impinger. Alternatively, the silica gel may be weighed directly in
the impinger just prior to final train assembly.
8.1.3.2 Based on the specific source sampling conditions, the
use of an empty first impinger can be eliminated if the moisture to
be collected in the impingers will be less than approximately 100
ml.
8.1.3.3 If Hg analysis will not be performed, the fourth, fifth,
and sixth impingers as shown in Figure 29-1 are not required.
8.1.3.4 To insure leak-free sampling train connections and to
prevent possible sample contamination problems, use Teflon tape or
other non-contaminating material instead of silicone grease.
Precaution: Exercise extreme care to prevent
contamination within the train. Prevent the acidic KMnO4 from
contacting any glassware that contains sample material to be
analyzed for Mn. Prevent acidic H2O2 from mixing with the acidic
KMnO4.
8.1.4 Leak-Check Procedures. Follow the leak-check procedures
given in Method 5, section 8.4.2 (Pretest Leak-Check), section
8.4.3 (Leak-Checks During the Sample Run), and section 8.4.4
(Post-Test Leak-Checks).
8.1.5 Sampling Train Operation. Follow the procedures given in
Method 5, section 8.5. When sampling for Hg, use a procedure
analogous to that described in section 8.1 of Method 101A, 40 CFR
Part 61, Appendix B, if necessary to maintain the desired color in
the last acidified permanganate impinger. For each run, record the
data required on a data sheet such as the one shown in Figure 5-3
of Method 5.
8.1.6 Calculation of Percent Isokinetic. Same as Method 5,
section 12.11.
8.2 Sample Recovery.
8.2.1 Begin cleanup procedures as soon as the probe is removed
from the stack at the end of a sampling period. The probe should be
allowed to cool prior to sample recovery. When it can be safely
handled, wipe off all external particulate matter near the tip of
the probe nozzle and place a rinsed, non-contaminating cap over the
probe nozzle to prevent losing or gaining particulate matter. Do
not cap the probe tip tightly while the sampling train is cooling;
a vacuum can form in the filter holder with the undesired result of
drawing liquid from the impingers onto the filter.
8.2.2 Before moving the sampling train to the cleanup site,
remove the probe from the sampling train and cap the open outlet.
Be careful not to lose any condensate that might be present. Cap
the filter inlet where the probe was fastened. Remove the umbilical
cord from the last impinger and cap the impinger. Cap the filter
holder outlet and impinger inlet. Use non-contaminating caps,
whether ground-glass stoppers, plastic caps, serum caps, or Teflon
® tape to close these openings.
8.2.3 Alternatively, the following procedure may be used to
disassemble the train before the probe and filter holder/oven are
completely cooled: Initially disconnect the filter holder
outlet/impinger inlet and loosely cap the open ends. Then
disconnect the probe from the filter holder or cyclone inlet and
loosely cap the open ends. Cap the probe tip and remove the
umbilical cord as previously described.
8.2.4 Transfer the probe and filter-impinger assembly to a
cleanup area that is clean and protected from the wind and other
potential causes of contamination or loss of sample. Inspect the
train before and during disassembly and note any abnormal
conditions. Take special precautions to assure that all the items
necessary for recovery do not contaminate the samples. The sample
is recovered and treated as follows (see schematic in Figures 29-2a
and 29-2b):
8.2.5 Container No. 1 (Sample Filter). Carefully remove the
filter from the filter holder and place it in its labeled petri
dish container. To handle the filter, use either acid-washed
polypropylene or Teflon coated tweezers or clean, disposable
surgical gloves rinsed with water and dried. If it is necessary to
fold the filter, make certain the particulate cake is inside the
fold. Carefully transfer the filter and any particulate matter or
filter fibers that adhere to the filter holder gasket to the petri
dish by using a dry (acid-cleaned) nylon bristle brush. Do not use
any metal-containing materials when recovering this train. Seal the
labeled petri dish.
8.2.6 Container No. 2 (Acetone Rinse). Perform this procedure
only if a determination of particulate emissions is to be made.
Quantitatively recover particulate matter and any condensate from
the probe nozzle, probe fitting, probe liner, and front half of the
filter holder by washing these components with a total of 100 ml of
acetone, while simultaneously taking great care to see that no dust
on the outside of the probe or other surfaces gets in the sample.
The use of exactly 100 ml is necessary for the subsequent blank
correction procedures. Distilled water may be used instead of
acetone when approved by the Administrator and shall be used when
specified by the Administrator; in these cases, save a water blank
and follow the Administrator's directions on analysis.
8.2.6.1 Carefully remove the probe nozzle, and clean the inside
surface by rinsing with acetone from a wash bottle while brushing
with a non-metallic brush. Brush until the acetone rinse shows no
visible particles, then make a final rinse of the inside surface
with acetone.
8.2.6.2 Brush and rinse the sample exposed inside parts of the
probe fitting with acetone in a similar way until no visible
particles remain. Rinse the probe liner with acetone by tilting and
rotating the probe while squirting acetone into its upper end so
that all inside surfaces will be wetted with acetone. Allow the
acetone to drain from the lower end into the sample container. A
funnel may be used to aid in transferring liquid washings to the
container. Follow the acetone rinse with a non-metallic probe
brush. Hold the probe in an inclined position, squirt acetone into
the upper end as the probe brush is being pushed with a twisting
action three times through the probe. Hold a sample container
underneath the lower end of the probe, and catch any acetone and
particulate matter which is brushed through the probe until no
visible particulate matter is carried out with the acetone or until
none remains in the probe liner on visual inspection. Rinse the
brush with acetone, and quantitatively collect these washings in
the sample container. After the brushing, make a final acetone
rinse of the probe as described above.
8.2.6.3 It is recommended that two people clean the probe to
minimize sample losses. Between sampling runs, keep brushes clean
and protected from contamination. Clean the inside of the
front-half of the filter holder by rubbing the surfaces with a
non-metallic brush and rinsing with acetone. Rinse each surface
three times or more if needed to remove visible particulate. Make a
final rinse of the brush and filter holder. After all acetone
washings and particulate matter have been collected in the sample
container, tighten the lid so that acetone will not leak out when
shipped to the laboratory. Mark the height of the fluid level to
determine whether or not leakage occurred during transport. Clearly
label the container to identify its contents.
8.2.7 Container No. 3 (Probe Rinse). Keep the probe assembly
clean and free from contamination during the probe rinse. Rinse the
probe nozzle and fitting, probe liner, and front-half of the filter
holder thoroughly with a total of 100 ml of 0.1 N HNO3, and place
the wash into a sample storage container. Perform the rinses as
applicable and generally as described in Method 12, section 8.7.1.
Record the volume of the rinses. Mark the height of the fluid level
on the outside of the storage container and use this mark to
determine if leakage occurs during transport. Seal the container,
and clearly label the contents. Finally, rinse the nozzle, probe
liner, and front-half of the filter holder with water followed by
acetone, and discard these rinses.
Note:
The use of a total of exactly 100 ml is necessary for the
subsequent blank correction procedures.
8.2.8 Container No. 4 (Impingers 1 through 3, Moisture Knockout
Impinger, when used, HNO3/H2O2 Impingers Contents and Rinses). Due
to the potentially large quantity of liquid involved, the tester
may place the impinger solutions from impingers 1 through 3 in more
than one container, if necessary. Measure the liquid in the first
three impingers to within 0.5 ml using a graduated cylinder. Record
the volume. This information is required to calculate the moisture
content of the sampled flue gas. Clean each of the first three
impingers, the filter support, the back half of the filter housing,
and connecting glassware by thoroughly rinsing with 100 ml of 0.1 N
HNO3 using the procedure as applicable in Method 12, section
8.7.3.
Note:
The use of exactly 100 ml of 0.1 N HNO3 rinse is necessary for
the subsequent blank correction procedures. Combine the rinses and
impinger solutions, measure and record the final total volume. Mark
the height of the fluid level, seal the container, and clearly
label the contents.
8.2.9 Container Nos. 5A (0.1 N HNO3), 5B (KMnO4/H2SO4 absorbing
solution), and 5C (8 N HCl rinse and dilution).
8.2.9.1 When sampling for Hg, pour all the liquid from the
impinger (normally impinger No. 4) that immediately preceded the
two permanganate impingers into a graduated cylinder and measure
the volume to within 0.5 ml. This information is required to
calculate the moisture content of the sampled flue gas. Place the
liquid in Container No. 5A. Rinse the impinger with exactly 100 ml
of 0.1 N HNO3 and place this rinse in Container No. 5A.
8.2.9.2 Pour all the liquid from the two permanganate impingers
into a graduated cylinder and measure the volume to within 0.5 ml.
This information is required to calculate the moisture content of
the sampled flue gas. Place this acidic KMnO4 solution into
Container No. 5B. Using a total of exactly 100 ml of fresh
acidified KMnO4 solution for all rinses (approximately 33 ml per
rinse), rinse the two permanganate impingers and connecting
glassware a minimum of three times. Pour the rinses into Container
No. 5B, carefully assuring transfer of all loose precipitated
materials from the two impingers. Similarly, using 100 ml total of
water, rinse the permanganate impingers and connecting glass a
minimum of three times, and pour the rinses into Container 5B,
carefully assuring transfer of any loose precipitated material.
Mark the height of the fluid level, and clearly label the contents.
Read the Precaution: in section 7.3.2.
Note:
Due to the potential reaction of KMnO4 with acid, pressure
buildup can occur in the sample storage bottles. Do not fill these
bottles completely and take precautions to relieve excess pressure.
A No. 70-72 hole drilled in the container cap and Teflon liner has
been used successfully.
8.2.9.3 Wash the two permanganate impingers with 25 ml of 8 N
HCl, and place the wash in a separate sample container labeled No.
5C containing 200 ml of water. First, place 200 ml of water in the
container. Then wash the impinger walls and stem with the 8 N HCl
by turning the impinger on its side and rotating it so that the HCl
contacts all inside surfaces. Use a total of only 25 ml of 8 N HCl
for rinsing both permanganate impingers combined. Rinse the
first impinger, then pour the actual rinse used for the first
impinger into the second impinger for its rinse. Finally, pour the
25 ml of 8 N HCl rinse carefully into the container with the 200 ml
of water. Mark the height of the fluid level on the outside of the
container in order to determine if leakage occurs during
transport.
8.2.10 Container No. 6 (Silica Gel). Note the color of the
indicating silica gel to determine whether it has been completely
spent and make a notation of its condition. Transfer the silica gel
from its impinger to its original container and seal it. The tester
may use a funnel to pour the silica gel and a rubber policeman to
remove the silica gel from the impinger. The small amount of
particles that might adhere to the impinger wall need not be
removed. Do not use water or other liquids to transfer the silica
gel since weight gained in the silica gel impinger is used for
moisture calculations. Alternatively, if a balance is available in
the field, record the weight of the spent silica gel (or silica gel
plus impinger) to the nearest 0.5 g.
8.2.11 Container No. 7 (Acetone Blank). If particulate emissions
are to be determined, at least once during each field test, place a
100-ml portion of the acetone used in the sample recovery process
into a container labeled No. 7. Seal the container.
8.2.12 Container No. 8A (0.1 N HNO3 Blank). At least once during
each field test, place 300 ml of the 0.1 N HNO3 solution used in
the sample recovery process into a container labeled No. 8A. Seal
the container.
8.2.13 Container No. 8B (Water Blank). At least once during each
field test, place 100 ml of the water used in the sample recovery
process into a container labeled No. 8B. Seal the container.
8.2.14 Container No. 9 (5 Percent HNO3/10 Percent H2O2 Blank).
At least once during each field test, place 200 ml of the 5 Percent
HNO3/10 Percent H2O2 solution used as the nitric acid impinger
reagent into a container labeled No. 9. Seal the container.
8.2.15 Container No. 10 (Acidified KMnO4 Blank). At least once
during each field test, place 100 ml of the acidified KMnO4
solution used as the impinger solution and in the sample recovery
process into a container labeled No. 10. Prepare the container as
described in section 8.2.9.2. Read the Precaution: in
section 7.3.2 and read the note in section 8.2.9.2.
8.2.16 Container No. 11 (8 N HCl Blank). At least once during
each field test, place 200 ml of water into a sample container
labeled No. 11. Then carefully add with stirring 25 ml of 8 N HCl.
Mix well and seal the container.
8.2.17 Container No. 12 (Sample Filter Blank). Once during each
field test, place into a petri dish labeled No. 12 three unused
blank filters from the same lot as the sampling filters. Seal the
petri dish.
8.3 Sample Preparation. Note the level of the liquid in each of
the containers and determine if any sample was lost during
shipment. If a noticeable amount of leakage has occurred, either
void the sample or use methods, subject to the approval of the
Administrator, to correct the final results. A diagram illustrating
sample preparation and analysis procedures for each of the sample
train components is shown in Figure 29-3.
8.3.1 Container No. 1 (Sample Filter).
8.3.1.1 If particulate emissions are being determined, first
desiccate the filter and filter catch without added heat (do not
heat the filters to speed the drying) and weigh to a constant
weight as described in section 11.2.1 of Method 5.
8.3.1.2 Following this procedure, or initially, if particulate
emissions are not being determined in addition to metals analysis,
divide the filter with its filter catch into portions containing
approximately 0.5 g each. Place the pieces in the analyst's choice
of either individual microwave pressure relief vessels or Parr
Bombs. Add 6 ml of concentrated HNO3 and 4 ml of concentrated HF to
each vessel. For microwave heating, microwave the samples for
approximately 12 to 15 minutes total heating time as follows: heat
for 2 to 3 minutes, then turn off the microwave for 2 to 3 minutes,
then heat for 2 to 3 minutes, etc., continue this alternation until
the 12 to 15 minutes total heating time are completed (this
procedure should comprise approximately 24 to 30 minutes at 600
watts). Microwave heating times are approximate and are dependent
upon the number of samples being digested simultaneously.
Sufficient heating is evidenced by sorbent reflux within the
vessel. For conventional heating, heat the Parr Bombs at 140 °C
(285 °F) for 6 hours. Then cool the samples to room temperature,
and combine with the acid digested probe rinse as required in
section 8.3.3.
8.3.1.3 If the sampling train includes an optional glass cyclone
in front of the filter, prepare and digest the cyclone catch by the
procedures described in section 8.3.1.2 and then combine the
digestate with the digested filter sample.
8.3.2 Container No. 2 (Acetone Rinse). Note the level of liquid
in the container and confirm on the analysis sheet whether or not
leakage occurred during transport. If a noticeable amount of
leakage has occurred, either void the sample or use methods,
subject to the approval of the Administrator, to correct the final
results. Measure the liquid in this container either volumetrically
within 1 ml or gravimetrically within 0.5 g. Transfer the contents
to an acid-cleaned, tared 250-ml beaker and evaporate to dryness at
ambient temperature and pressure. If particulate emissions are
being determined, desiccate for 24 hours without added heat, weigh
to a constant weight according to the procedures described in
section 11.2.1 of Method 5, and report the results to the nearest
0.1 mg. Redissolve the residue with 10 ml of concentrated HNO3.
Quantitatively combine the resultant sample, including all liquid
and any particulate matter, with Container No. 3 before beginning
section 8.3.3.
8.3.3 Container No. 3 (Probe Rinse). Verify that the pH of this
sample is 2 or lower. If it is not, acidify the sample by careful
addition with stirring of concentrated HNO3 to pH 2. Use water to
rinse the sample into a beaker, and cover the beaker with a ribbed
watch glass. Reduce the sample volume to approximately 20 ml by
heating on a hot plate at a temperature just below boiling. Digest
the sample in microwave vessels or Parr Bombs by quantitatively
transferring the sample to the vessel or bomb, carefully adding the
6 ml of concentrated HNO3, 4 ml of concentrated HF, and then
continuing to follow the procedures described in section 8.3.1.2.
Then combine the resultant sample directly with the acid digested
portions of the filter prepared previously in section 8.3.1.2. The
resultant combined sample is referred to as “Sample Fraction
1”. Filter the combined sample using Whatman 541 filter paper.
Dilute to 300 ml (or the appropriate volume for the expected metals
concentration) with water. This diluted sample is “Analytical
Fraction 1”. Measure and record the volume of Analytical
Fraction 1 to within 0.1 ml. Quantitatively remove a 50-ml aliquot
and label as “Analytical Fraction 1B”. Label the remaining
250-ml portion as “Analytical Fraction 1A”. Analytical
Fraction 1A is used for ICAP or AAS analysis for all desired metals
except Hg. Analytical Fraction 1B is used for the determination of
front-half Hg.
8.3.4 Container No. 4 (Impingers 1-3). Measure and record the
total volume of this sample to within 0.5 ml and label it
“Sample Fraction 2”. Remove a 75- to 100-ml aliquot for Hg
analysis and label the aliquot “Analytical Fraction 2B”.
Label the remaining portion of Container No. 4 as “Sample
Fraction 2A”. Sample Fraction 2A defines the volume of
Analytical Fraction 2A prior to digestion. All of Sample
Fraction 2A is digested to produce “Analytical Fraction 2A”.
Analytical Fraction 2A defines the volume of Sample Fraction 2A
after its digestion and the volume of Analytical Fraction 2A
is normally 150 ml. Analytical Fraction 2A is analyzed for all
metals except Hg. Verify that the pH of Sample Fraction 2A is 2 or
lower. If necessary, use concentrated HNO3 by careful addition and
stirring to lower Sample Fraction 2A to pH 2. Use water to rinse
Sample Fraction 2A into a beaker and then cover the beaker with a
ribbed watchglass. Reduce Sample Fraction 2A to approximately 20 ml
by heating on a hot plate at a temperature just below boiling. Then
follow either of the digestion procedures described in sections
8.3.4.1 or 8.3.4.2.
8.3.4.1 Conventional Digestion Procedure. Add 30 ml of 50
percent HNO3, and heat for 30 minutes on a hot plate to just below
boiling. Add 10 ml of 3 percent H2O2 and heat for 10 more minutes.
Add 50 ml of hot water, and heat the sample for an additional 20
minutes. Cool, filter the sample, and dilute to 150 ml (or the
appropriate volume for the expected metals concentrations) with
water. This dilution produces Analytical Fraction 2A. Measure and
record the volume to within 0.1 ml.
8.3.4.2 Microwave Digestion Procedure. Add 10 ml of 50 percent
HNO3 and heat for 6 minutes total heating time in
alternations of 1 to 2 minutes at 600 Watts followed by 1 to 2
minutes with no power, etc., similar to the procedure described in
section 8.3.1. Allow the sample to cool. Add 10 ml of 3 percent
H2O2 and heat for 2 more minutes. Add 50 ml of hot water, and heat
for an additional 5 minutes. Cool, filter the sample, and dilute to
150 ml (or the appropriate volume for the expected metals
concentrations) with water. This dilution produces Analytical
Fraction 2A. Measure and record the volume to within 0.1 ml.
Note:
All microwave heating times given are approximate and are
dependent upon the number of samples being digested at a time.
Heating times as given above have been found acceptable for
simultaneous digestion of up to 12 individual samples. Sufficient
heating is evidenced by solvent reflux within the vessel.
8.3.5 Container No. 5A (Impinger 4), Container Nos. 5B and 5C
(Impingers 5 and 6). Keep the samples in Containers Nos. 5A, 5B,
and 5C separate from each other. Measure and record the volume of
5A to within 0.5 ml. Label the contents of Container No. 5A to be
Analytical Fraction 3A. To remove any brown MnO2 precipitate from
the contents of Container No. 5B, filter its contents through
Whatman 40 filter paper into a 500 ml volumetric flask and dilute
to volume with water. Save the filter for digestion of the brown
MnO2 precipitate. Label the 500 ml filtrate from Container No. 5B
to be Analytical Fraction 3B. Analyze Analytical Fraction 3B for Hg
within 48 hours of the filtration step. Place the saved filter,
which was used to remove the brown MnO2 precipitate, into an
appropriately sized vented container, which will allow
release of any gases including chlorine formed when the filter is
digested. In a laboratory hood which will remove any gas produced
by the digestion of the MnO2, add 25 ml of 8 N HCl to the filter
and allow to digest for a minimum of 24 hours at room temperature.
Filter the contents of Container No. 5C through a Whatman 40 filter
into a 500-ml volumetric flask. Then filter the result of the
digestion of the brown MnO2 from Container No. 5B through a Whatman
40 filter into the same 500-ml volumetric flask, and dilute and mix
well to volume with water. Discard the Whatman 40 filter. Mark this
combined 500-ml dilute HCl solution as Analytical Fraction 3C.
8.3.6 Container No. 6 (Silica Gel). Weigh the spent silica gel
(or silica gel plus impinger) to the nearest 0.5 g using a
balance.
9.0 Quality Control
9.1 Field Reagent Blanks, if analyzed. Perform the digestion and
analysis of the blanks in Container Nos. 7 through 12 that were
produced in sections 8.2.11 through 8.2.17, respectively. For Hg
field reagent blanks, use a 10 ml aliquot for digestion and
analysis.
9.1.1 Digest and analyze one of the filters from Container No.
12 per section 8.3.1, 100 ml from Container No. 7 per section
8.3.2, and 100 ml from Container No. 8A per section 8.3.3. This
step produces blanks for Analytical Fractions 1A and 1B.
9.1.2 Combine 100 ml of Container No. 8A with 200 ml from
Container No. 9, and digest and analyze the resultant volume per
section 8.3.4. This step produces blanks for Analytical Fractions
2A and 2B.
9.1.3 Digest and analyze a 100-ml portion of Container No. 8A to
produce a blank for Analytical Fraction 3A.
9.1.4 Combine 100 ml from Container No. 10 with 33 ml from
Container No. 8B to produce a blank for Analytical Fraction 3B.
Filter the resultant 133 ml as described for Container No. 5B in
section 8.3.5, except do not dilute the 133 ml. Analyze this blank
for Hg within 48 hr of the filtration step, and use 400 ml as the
blank volume when calculating the blank mass value. Use the actual
volumes of the other analytical blanks when calculating their mass
values.
9.1.5 Digest the filter that was used to remove any brown MnO2
precipitate from the blank for Analytical Fraction 3B by the same
procedure as described in section 8.3.5 for the similar sample
filter. Filter the digestate and the contents of Container No. 11
through Whatman 40 paper into a 500-ml volumetric flask, and dilute
to volume with water. These steps produce a blank for Analytical
Fraction 3C.
9.1.6 Analyze the blanks for Analytical Fraction Blanks 1A and
2A per section 11.1.1 and/or section 11.1.2. Analyze the blanks for
Analytical Fractions 1B, 2B, 3A, 3B, and 3C per section 11.1.3.
Analysis of the blank for Analytical Fraction 1A produces the
front-half reagent blank correction values for the desired metals
except for Hg; Analysis of the blank for Analytical Fraction 1B
produces the front-half reagent blank correction value for Hg.
Analysis of the blank for Analytical Fraction 2A produces the
back-half reagent blank correction values for all of the desired
metals except for Hg, while separate analyses of the blanks for
Analytical Fractions 2B, 3A, 3B, and 3C produce the back-half
reagent blank correction value for Hg.
9.2 Quality Control Samples. Analyze the following quality
control samples.
9.2.1 ICAP and ICP-MS Analysis. Follow the respective quality
control descriptions in section 8 of Methods 6010 and 6020 in EPA
Publication SW-846 Third Edition (November 1986) including updates
I, II, IIA, IIB and III, as incorporated by reference in §
60.17(i). For the purposes of a source test that consists of three
sample runs, modify those requirements to include the following:
two instrument check standard runs, two calibration blank runs, one
interference check sample at the beginning of the analysis (analyze
by Method of Standard Additions unless within 25 percent), one
quality control sample to check the accuracy of the calibration
standards (required to be within 25 percent of calibration), and
one duplicate analysis (required to be within 20 percent of average
or repeat all analyses).
9.2.2 Direct Aspiration AAS and/or GFAAS Analysis for Sb, As,
Ba, Be, Cd, Cu, Cr, Co, Pb, Ni, Mn, Hg, P, Se, Ag, Tl, and Zn.
Analyze all samples in duplicate. Perform a matrix spike on at
least one front-half sample and one back-half sample, or one
combined sample. If recoveries of less than 75 percent or greater
than 125 percent are obtained for the matrix spike, analyze each
sample by the Method of Standard Additions. Analyze a quality
control sample to check the accuracy of the calibration standards.
If the results are not within 20 percent, repeat the
calibration.
9.2.3 CVAAS Analysis for Hg. Analyze all samples in duplicate.
Analyze a quality control sample to check the accuracy of the
calibration standards (if not within 15 percent, repeat
calibration). Perform a matrix spike on one sample (if not within
25 percent, analyze all samples by the Method of Standard
Additions). Additional information on quality control can be
obtained from Method 7470 in EPA Publication SW-846 Third Edition
(November 1986) including updates I, II, IIA, IIB and III, as
incorporated by reference in § 60.17(i), or in Standard Methods
for Water and Wastewater Method 303F.
10.0 Calibration and Standardization Note:
Maintain a laboratory log of all calibrations.
10.1 Sampling Train Calibration. Calibrate the sampling train
components according to the indicated sections of Method 5: Probe
Nozzle (Section 10.1); Pitot Tube (Section 10.2); Metering System
(Section 10.3); Probe Heater (Section 10.4); Temperature Sensors
(Section 10.5); Leak-Check of the Metering System (Section 8.4.1);
and Barometer (Section 10.6).
10.2 Inductively Coupled Argon Plasma Spectrometer Calibration.
Prepare standards as outlined in section 7.5. Profile and calibrate
the instrument according to the manufacturer's recommended
procedures using those standards. Check the calibration once per
hour. If the instrument does not reproduce the standard
concentrations within 10 percent, perform the complete calibration
procedures. Perform ICP-MS analysis by following Method 6020 in EPA
Publication SW-846 Third Edition (November 1986) including updates
I, II, IIA, IIB and III, as incorporated by reference in §
60.17(i).
10.3 Atomic Absorption Spectrometer - Direct Aspiration AAS,
GFAAS, and CVAAS analyses. Prepare the standards as outlined in
section 7.5 and use them to calibrate the spectrometer. Calibration
procedures are also outlined in the EPA methods referred to in
Table 29-2 and in Method 7470 in EPA Publication SW-846 Third
Edition (November 1986) including updates I, II, IIA, IIB and III,
as incorporated by reference in § 60.17(i), or in Standard
Methods for Water and Wastewater Method 303F (for Hg). Run each
standard curve in duplicate and use the mean values to calculate
the calibration line. Recalibrate the instrument approximately once
every 10 to 12 samples.
10.4 Field Balance Calibration Check. Check the calibration of
the balance used to weigh impingers with a weight that is at least
500g or within 50g of a loaded impinger. The weight must be ASTM
E617-13 “Standard Specification for Laboratory Weights and
Precision Mass Standards” (incorporated by reference-see 40 CFR
60.17) Class 6 (or better). Daily before use, the field balance
must measure the weight within ±0.5g of the certified mass. If the
daily balance calibration check fails, perform corrective measures
and repeat the check before using balance.
10.5 Analytical Balance Calibration. Perform a multipoint
calibration (at least five points spanning the operational range)
of the analytical balance before the first use, and semiannually
thereafter. The calibration of the analytical balance must be
conducted using ASTM E617-13 “Standard Specification for Laboratory
Weights and Precision Mass Standards” (incorporated by reference -
see 40 CFR 60.17) Class 2 (or better) tolerance weights. Audit the
balance each day it is used for gravimetric measurements by
weighing at least one ASTM E617-13 Class 2 tolerance (or better)
calibration weight that corresponds to 50 to 150 percent of the
weight of one filter or between 1g and 5g. If the scale cannot
reproduce the value of the calibration weight to within 0.5 mg of
the certified mass, perform corrective measures, and conduct the
multipoint calibration before use.
11.0 Analytical Procedure
11.1 Sample Analysis. For each sampling train sample run, seven
individual analytical samples are generated; two for all desired
metals except Hg, and five for Hg. A schematic identifying each
sample container and the prescribed analytical preparation and
analysis scheme is shown in Figure 29-3. The first two analytical
samples, labeled Analytical Fractions 1A and 1B, consist of the
digested samples from the front-half of the train. Analytical
Fraction 1A is for ICAP, ICP-MS or AAS analysis as described in
sections 11.1.1 and 11.1.2, respectively. Analytical Fraction 1B is
for front-half Hg analysis as described in section 11.1.3. The
contents of the back-half of the train are used to prepare the
third through seventh analytical samples. The third and fourth
analytical samples, labeled Analytical Fractions 2A and 2B, contain
the samples from the moisture removal impinger No. 1, if used, and
HNO3/H2O2 impingers Nos. 2 and 3. Analytical Fraction 2A is for
ICAP, ICP-MS or AAS analysis for target metals, except Hg.
Analytical Fraction 2B is for analysis for Hg. The fifth through
seventh analytical samples, labeled Analytical Fractions 3A, 3B,
and 3C, consist of the impinger contents and rinses from the empty
impinger No. 4 and the H2SO4/KMnO4 Impingers Nos. 5 and 6. These
analytical samples are for analysis for Hg as described in section
11.1.3. The total back-half Hg catch is determined from the sum of
Analytical Fractions 2B, 3A, 3B, and 3C. Analytical Fractions 1A
and 2A can be combined proportionally prior to analysis.
11.1.1 ICAP and ICP-MS Analysis. Analyze Analytical Fractions 1A
and 2A by ICAP using Method 6010 or Method 200.7 (40 CFR 136,
Appendix C). Calibrate the ICAP, and set up an analysis program as
described in Method 6010 or Method 200.7. Follow the quality
control procedures described in section 9.2.1. Recommended
wavelengths for analysis are as shown in Table 29-2. These
wavelengths represent the best combination of specificity and
potential detection limit. Other wavelengths may be substituted if
they can provide the needed specificity and detection limit, and
are treated with the same corrective techniques for spectral
interference. Initially, analyze all samples for the target metals
(except Hg) plus Fe and Al. If Fe and Al are present, the sample
might have to be diluted so that each of these elements is at a
concentration of less than 50 ppm so as to reduce their spectral
interferences on As, Cd, Cr, and Pb. Perform ICP-MS analysis by
following Method 6020 in EPA Publication SW-846 Third Edition
(November 1986) including updates I, II, IIA, IIB and III, as
incorporated by reference in § 60.17(i).
Note:
When analyzing samples in a HF matrix, an alumina torch should
be used; since all front-half samples will contain HF, use an
alumina torch.
11.1.2 AAS by Direct Aspiration and/or GFAAS. If analysis of
metals in Analytical Fractions 1A and 2A by using GFAAS or direct
aspiration AAS is needed, use Table 29-3 to determine which
techniques and procedures to apply for each target metal. Use Table
29-3, if necessary, to determine techniques for minimization of
interferences. Calibrate the instrument according to section 10.3
and follow the quality control procedures specified in section
9.2.2.
11.1.3 CVAAS Hg analysis. Analyze Analytical Fractions 1B, 2B,
3A, 3B, and 3C separately for Hg using CVAAS following the method
outlined in Method 7470 in EPA Publication SW-846 Third Edition
(November 1986) including updates I, II, IIA, IIB and III, as
incorporated by reference in § 60.17(i), or in Standard Methods
for Water and Wastewater Analysis, 15th Edition, Method 303F,
or, optionally using note no. 2 at the end of this section. Set up
the calibration curve (zero to 1000 ng) as described in Method 7470
or similar to Method 303F using 300-ml BOD bottles instead of
Erlenmeyers. Perform the following for each Hg analysis. From each
original sample, select and record an aliquot in the size range
from 1 ml to 10 ml. If no prior knowledge of the expected amount of
Hg in the sample exists, a 5 ml aliquot is suggested for the first
dilution to 100 ml (see note no. 1 at end of this section). The
total amount of Hg in the aliquot shall be less than 1 µg and
within the range (zero to 1000 ng) of the calibration curve. Place
the sample aliquot into a separate 300-ml BOD bottle, and add
enough water to make a total volume of 100 ml. Next add to it
sequentially the sample digestion solutions and perform the sample
preparation described in the procedures of Method 7470 or Method
303F. (See note no. 2 at the end of this section). If the maximum
readings are off-scale (because Hg in the aliquot exceeded the
calibration range; including the situation where only a 1-ml
aliquot of the original sample was digested), then dilute the
original sample (or a portion of it) with 0.15 percent HNO3 (1.5 ml
concentrated HNO3 per liter aqueous solution) so that when a 1- to
10-ml aliquot of the “0.15 HNO3 percent dilution of the original
sample” is digested and analyzed by the procedures described above,
it will yield an analysis within the range of the calibration
curve.
Note No. 1:
When Hg levels in the sample fractions are below the in-stack
detection limit given in Table 29-1, select a 10 ml aliquot for
digestion and analysis as described.
Note No. 2:
Optionally, Hg can be analyzed by using the CVAAS analytical
procedures given by some instrument manufacturer's directions.
These include calibration and quality control procedures for the
Leeman Model PS200, the Perkin Elmer FIAS systems, and similar
models, if available, of other instrument manufacturers. For
digestion and analyses by these instruments, perform the following
two steps: (1), Digest the sample aliquot through the addition of
the aqueous hydroxylamine hydrochloride/sodium chloride solution
the same as described in this section: (The Leeman, Perkin
Elmer, and similar instruments described in this note add
automatically the necessary stannous chloride solution during the
automated analysis of Hg.); (2), Upon completion of the
digestion described in (1), analyze the sample according to the
instrument manufacturer's directions. This approach allows multiple
(including duplicate) automated analyses of a digested sample
aliquot.
12.0 Data Analysis and Calculations
12.1 Nomenclature.
A = Analytical detection limit, µg/ml. B = Liquid volume of
digested sample prior to aliquotting for analysis, ml. C = Stack
sample gas volume, dsm 3. Ca1 = Concentration of metal in
Analytical Fraction 1A as read from the standard curve, µg/ml. Ca2
= Concentration of metal in Analytical Fraction 2A as read from the
standard curve, (µg/ml). Cs = Concentration of a metal in the stack
gas, mg/dscm. D = In-stack detection limit, µg/m 3. Fa = Aliquot
factor, volume of Sample Fraction 2 divided by volume of Sample
Fraction 2A (see section 8.3.4.) Fd = Dilution factor (Fd = the
inverse of the fractional portion of the concentrated sample in the
solution actually used in the instrument to produce the reading
Ca1. For example, if a 2 ml aliquot of Analytical Fraction 1A is
diluted to 10 ml to place it in the calibration range, Fd = 5).
Hgbh = Total mass of Hg collected in the back-half of the sampling
train, µg. Hgbh2 = Total mass of Hg collected in Sample Fraction 2,
µg. Hgbh3(A,B,C) = Total mass of Hg collected separately in
Fraction 3A, 3B, or 3C, µg. Hgbhb = Blank correction value for mass
of Hg detected in back-half field reagent blanks, µg. Hgfh = Total
mass of Hg collected in the front-half of the sampling train
(Sample Fraction 1), µg. Hgfhb = Blank correction value for mass of
Hg detected in front-half field reagent blank, µg. Hgt = Total mass
of Hg collected in the sampling train, µg. Mbh = Total mass of each
metal (except Hg) collected in the back-half of the sampling train
(Sample Fraction 2), µg. Mbhb = Blank correction value for mass of
metal detected in back-half field reagent blank, µg. Mfh = Total
mass of each metal (except Hg) collected in the front half of the
sampling train (Sample Fraction 1), µg. Mfhb = Blank correction
value for mass of metal detected in front-half field reagent blank,
µg. Mt = Total mass of each metal (separately stated for each
metal) collected in the sampling train, µg. Mt = Total mass of that
metal collected in the sampling train, µg; (substitute Hgt for Mt
for the Hg calculation). Qbh2 = Quantity of Hg, µg, TOTAL in the
ALIQUOT of Analytical Fraction 2B selected for digestion and
analysis . Note:
For example, if a 10 ml aliquot of Analytical Fraction 2B is
taken and digested and analyzed (according to section 11.1.3 and
its notes nos. 1 and 2), then calculate and use the total amount of
Hg in the 10 ml aliquot for Qbh2.
Qbh3(A,B,C) = Quantity of Hg, µg, TOTAL, separately, in the
ALIQUOT of Analytical Fraction 3A, 3B, or 3C selected for digestion
and analysis (see notes in sections 12.7.1 and 12.7.2
describing the quantity “Q” and calculate similarly). Qfh =
Quantity of Hg, µg, TOTAL in the ALIQUOT of Analytical Fraction
1B selected for digestion and analysis. Note:
For example, if a 10 ml aliquot of Analytical Fraction 1B is
taken and digested and analyzed (according to section 11.1.3 and
its notes nos. 1 and 2), then calculate and use the total amount of
Hg in the 10 ml aliquot for Qfh.
Va = Total volume of digested sample solution (Analytical Fraction
2A), ml (see section 8.3.4.1 or 8.3.4.2, as applicable). Vf1B =
Volume of aliquot of Analytical Fraction 1B analyzed, ml. Note:
For example, if a 1 ml aliquot of Analytical Fraction 1B was
diluted to 50 ml with 0.15 percent HNO3 as described in section
11.1.3 to bring it into the proper analytical range, and then 1 ml
of that 50-ml was digested according to section 11.1.3 and
analyzed, Vf1B would be 0.02 ml.
Vf2B = Volume of Analytical Fraction 2B analyzed, ml. Note:
For example, if 1 ml of Analytical Fraction 2B was diluted to 10
ml with 0.15 percent HNO3 as described in section 11.1.3 to bring
it into the proper analytical range, and then 5 ml of that 10 ml
was analyzed, Vf2B would be 0.5 ml.
Vf3(A,B,C) = Volume, separately, of Analytical Fraction 3A, 3B, or
3C analyzed, ml (see previous notes in sections 12.7.1 and 12.7.2,
describing the quantity “V” and calculate similarly). Vm(std) =
Volume of gas sample as measured by the dry gas meter, corrected to
dry standard conditions, dscm. Vsoln,1 = Total volume of digested
sample solution (Analytical Fraction 1), ml. Vsoln,1 = Total volume
of Analytical Fraction 1, ml. Vsoln,2 = Total volume of Sample
Fraction 2, ml.
Vsoln,3(A,B,C) = Total volume, separately, of Analytical
Fraction 3A, 3B, or 3C, ml.
K4 = 10−3 mg/µg.
12.2 Dry Gas Volume. Using the data from this test, calculate
Vm(std), the dry gas sample volume at standard conditions as
outlined in section 12.3 of Method 5.
12.3 Volume of Water Vapor and Moisture Content. Using the total
volume of condensate collected during the source sampling,
calculate the volume of water vapor Vw(std) and the moisture
content Bws of the stack gas. Use Equations 5-2 and 5-3 of Method
5.
12.4 Stack Gas Velocity. Using the data from this test and
Equation 2-9 of Method 2, calculate the average stack gas
velocity.
12.5 In-Stack Detection Limits. Calculate the in-stack method
detection limits shown in Table 29-4 using the conditions described
in section 13.3.1 as follows:
12.6 Metals (Except Hg) in Source Sample.
12.6.1 Analytical Fraction 1A, Front-Half, Metals (except Hg).
Calculate separately the amount of each metal collected in Sample
Fraction 1 of the sampling train using the following equation:
Note:
If Analytical Fractions 1A and 2A are combined, use proportional
aliquots. Then make appropriate changes in Equations 29-2 through
29-4 to reflect this approach.
12.6.2 Analytical Fraction 2A, Back-Half, Metals (except Hg).
Calculate separately the amount of each metal collected in Fraction
2 of the sampling train using the following equation:
12.6.3 Total Train, Metals (except Hg). Calculate the total
amount of each of the quantified metals collected in the sampling
train as follows:
Note:
If the measured blank value for the front half (Mfhb) is in the
range 0.0 to “A” µg (where “A” µg equals the value determined by
multiplying 1.4 µg/in.2 times the actual area in in.2 of the sample
filter), use Mfhb to correct the emission sample value (Mfh); if
Mfhb exceeds “A” µg, use the greater of I or II:
I. “A” µg.
II. The lesser of (a) Mfhb, or (b) 5 percent of Mfh. If the
measured blank value for the back-half (Mbhb) is in the range 0.0
to 1 µg, use Mbhb to correct the emission sample value (Mbh); if
Mbhb exceeds 1 µg, use the greater of I or II:
I. 1 µg.
II. The lesser of (a) Mbhb, or (b) 5 percent of Mbh.
12.7 Hg in Source Sample.
12.7.1 Analytical Fraction 1B; Front-Half Hg. Calculate the
amount ofHg collected in the front-half, Sample Fraction 1, of the
sampling train by using Equation 29-5:
12.7.2 Analytical Fractions 2B, 3A, 3B, and 3C; Back Half
Hg.
12.7.2.1 Calculate the amount of Hg collected in Sample Fraction
2 by using Equation 29-6:
12.7.2.2 Calculate each of the back-half Hg values for
Analytical Fractions 3A, 3B, and 3C by using Equation 29-7:
12.7.2.3 Calculate the total amount of Hg collected in the
back-half of the sampling train by using Equation 29-8:
12.7.3 Total Train Hg Catch. Calculate the total amount of Hg
collected in the sampling train by using Equation 29-9:
Note:
If the total of the measured blank values (Hgfhb + Hgbhb) is in
the range of 0.0 to 0.6 µg, then use the total to correct the
sample value (Hgfh + Hgbh); if it exceeds 0.6 µg, use the greater
of I. or II:
I. 0.6 µg.
II. The lesser of (a) (Hgfhb + Hgbhb), or (b) 5 percent of the
sample value (Hgfh + Hgbh).
12.8 Individual Metal Concentrations in Stack Gas. Calculate the
concentration of each metal in the stack gas (dry basis, adjusted
to standard conditions) by using Equation 29-10:
12.9 Isokinetic Variation and Acceptable Results. Same as Method
5, sections 12.11 and 12.12, respectively.
13.0 Method Performance
13.1 Range. For the analysis described and for similar analyses,
the ICAP response is linear over several orders of magnitude.
Samples containing metal concentrations in the nanograms per ml
(ng/ml) to micrograms per ml (µg/ml) range in the final analytical
solution can be analyzed using this method. Samples containing
greater than approximately 50 µg/ml As, Cr, or Pb should be diluted
to that level or lower for final analysis. Samples containing
greater than approximately 20 µg/ml of Cd should be diluted to that
level before analysis.
13.2 Analytical Detection Limits.
Note:
See section 13.3 for the description of in-stack detection
limits.
13.2.1 ICAP analytical detection limits for the sample solutions
(based on SW-846, Method 6010) are approximately as follows:
Sb (32 ng/ml), As (53 ng/ml), Ba (2 ng/ml), Be (0.3 ng/ml), Cd (4
ng/ml), Cr (7 ng/ml), Co (7 ng/ml), Cu (6 ng/ml), Pb (42 ng/ml), Mn
(2 ng/ml), Ni (15 ng/ml), P (75 ng/ml), Se (75 ng/ml), Ag (7
ng/ml), Tl (40 ng/ml), and Zn (2 ng/ml). ICP-MS analytical
detection limits (based on SW-846, Method 6020) are lower
generally by a factor of ten or more. Be is lower by a factor of
three. The actual sample analytical detection limits are sample
dependent and may vary due to the sample matrix.
13.2.2 The analytical detection limits for analysis by direct
aspiration AAS (based on SW-846, Method 7000 series) are
approximately as follows: Sb (200 ng/ml), As (2 ng/ml), Ba (100
ng/ml), Be (5 ng/ml), Cd (5 ng/ml), Cr (50 ng/ml), Co (50 ng/ml),
Cu (20 ng/ml), Pb (100 ng/ml), Mn (10 ng/ml), Ni (40 ng/ml), Se (2
ng/ml), Ag (10 ng/ml), Tl (100 ng/ml), and Zn (5 ng/ml).
13.2.3 The detection limit for Hg by CVAAS (on the resultant
volume of the digestion of the aliquots taken for Hg
analyses) can be approximately 0.02 to 0.2 ng/ml, depending upon
the type of CVAAS analytical instrument used. 13.2.4 The use of
GFAAS can enhance the detection limits compared to direct
aspiration AAS as follows: Sb (3 ng/ml), As (1 ng/ml), Be (0.2
ng/ml), Cd (0.1 ng/ml), Cr (1 ng/ml), Co (1 ng/ml), Pb (1 ng/ml),
Se (2 ng/ml), and Tl (1 ng/ml).
13.3 In-stack Detection Limits.
13.3.1 For test planning purposes in-stack detection limits can
be developed by using the following information: (1) The procedures
described in this method, (2) the analytical detection limits
described in section 13.2 and in SW-846,(3) the normal
volumes of 300 ml (Analytical Fraction 1) for the front-half and
150 ml (Analytical Fraction 2A) for the back-half samples, and (4)
a stack gas sample volume of 1.25 m 3. The resultant in-stack
method detection limits for the above set of conditions are
presented in Table 29-1 and were calculated by using Eq. 29-1 shown
in section 12.5.
13.3.2 To ensure optimum precision/resolution in the analyses,
the target concentrations of metals in the analytical solutions
should be at least ten times their respective analytical detection
limits. Under certain conditions, and with greater care in the
analytical procedure, these concentrations can be as low as
approximately three times the respective analytical detection
limits without seriously impairing the precision of the analyses.
On at least one sample run in the source test, and for each metal
analyzed, perform either repetitive analyses, Method of Standard
Additions, serial dilution, or matrix spike addition, etc., to
document the quality of the data.
13.3.3 Actual in-stack method detection limits are based on
actual source sampling parameters and analytical results as
described above. If required, the method in-stack detection limits
can be improved over those shown in Table 29-1 for a specific test
by either increasing the sampled stack gas volume, reducing the
total volume of the digested samples, improving the analytical
detection limits, or any combination of the three. For extremely
low levels of Hg only, the aliquot size selected for
digestion and analysis can be increased to as much as 10 ml, thus
improving the in-stack detection limit by a factor of ten compared
to a 1 ml aliquot size.
13.3.3.1 A nominal one hour sampling run will collect a stack
gas sampling volume of about 1.25 m 3. If the sampling time is
increased to four hours and 5 m 3 are collected, the in-stack
method detection limits would be improved by a factor of four
compared to the values shown in Table 29-1.
13.3.3.2 The in-stack detection limits assume that all of the
sample is digested and the final liquid volumes for analysis are
the normal values of 300 ml for Analytical Fraction 1, and 150 ml
for Analytical Fraction 2A. If the volume of Analytical Fraction 1
is reduced from 300 to 30 ml, the in-stack detection limits for
that fraction of the sample would be improved by a factor of ten.
If the volume of Analytical Fraction 2A is reduced from 150 to 25
ml, the in-stack detection limits for that fraction of the sample
would be improved by a factor of six. Matrix effect checks are
necessary on sample analyses and typically are of much greater
significance for samples that have been concentrated to less than
the normal original sample volume. Reduction of Analytical
Fractions 1 and 2A to volumes of less than 30 and 25 ml,
respectively, could interfere with the redissolving of the residue
and could increase interference by other compounds to an
intolerable level.
13.3.3.3 When both of the modifications described in sections
13.3.3.1 and 13.3.3.2 are used simultaneously on one sample, the
resultant improvements are multiplicative. For example, an increase
in stack gas volume by a factor of four and a reduction in the
total liquid sample digested volume of both Analytical Fractions 1
and 2A by a factor of six would result in an improvement by a
factor of twenty-four of the in-stack method detection limit.
13.4 Precision. The precision (relative standard deviation) for
each metal detected in a method development test performed at a
sewage sludge incinerator were found to be as follows:
Sb (12.7 percent), As (13.5 percent), Ba (20.6 percent), Cd (11.5
percent), Cr (11.2 percent), Cu (11.5 percent), Pb (11.6 percent),
P (14.6 percent), Se (15.3 percent), Tl (12.3 percent), and Zn
(11.8 percent). The precision for Ni was 7.7 percent for another
test conducted at a source simulator. Be, Mn, and Ag were not
detected in the tests. However, based on the analytical detection
limits of the ICAP for these metals, their precisions could be
similar to those for the other metals when detected at similar
levels. 14.0 Pollution Prevention [Reserved] 15.0 Waste Management
[Reserved] 16.0 Alternative Procedures
16.1 Alternative Analyzer. Samples may also be analyzed by cold
vapor atomic fluorescence spectrometry.
16.2 [Reserved]
17.0 References
1. Method 303F in Standard Methods for the Examination of
Water Wastewater, 15th Edition, 1980. Available from the
American Public Health Association, 1015 18th Street N.W.,
Washington, D.C. 20036.
2. EPA Methods 6010, 6020, 7000, 7041, 7060, 7131, 7421, 7470,
7740, and 7841, Test Methods for Evaluating Solid Waste:
Physical/Chemical Methods. SW-846, Third Edition, November
1986, with updates I, II, IIA, IIB and III. Office of Solid Waste
and Emergency Response, U. S. Environmental Protection Agency,
Washington, DC 20460.
3. EPA Method 200.7, Code of Federal Regulations, Title 40, Part
136, Appendix C. July 1, 1987.
4. EPA Methods 1 through 5, Code of Federal Regulations, Title
40, Part 60, Appendix A, July 1, 1991.
5. EPA Method 101A, Code of Federal Regulations, Title 40, Part
61, Appendix B, July 1, 1991.
18.0 Tables, Diagrams, Flowcharts, and Validation Data
Table 29-1 - In Stack Method Detection
Limits (ug/m 3) for the Front-Half, the Back Half, and
the Total Sampling Train Using ICAP, GFAAS, and CVAAS
Metal
Front-half: probe and
filter
Back-half: impinters 1-3
Back-half: impringers
4-6 a
Total train
Antimony
1 7.7 (0.7)
1 3.8 (0.4)
1 11.5 (1.1)
Arsenic
1 12.7 (0.3)
1 6.4 (0.1)
1 19.1 (0.4)
Barium
0.5
0.3
0.8
Beryllium
1 0.07 (0.05)
1 0.04 (0.03)
1 0.11 (0.08)
Cadmium
1 1.0 (0.02)
1 0.5 (0.01)
1 1.5 (0.03)
Chromium
1 1.7 (0.2)
1 0.8 (0.1)
1 2.5 (0.3)
Cobalt
1 1.7 (0.2)
1 0.8 (0.1)
1 2.5 (0.3)
Copper
1.4
0.7
2.1
Lead
1 10.1 (0.2)
1 5.0 (0.1)
1 15.1 (0.3)
Manganese
1 0.5 (0.2)
1 0.2 (0.1)
1 0.7 (0.3)
Mercury
2 0.06
2 0.3
2 0.2
2 0.56
Nickel
3.6
1.8
5.4
Phosphorus
18
9
27
Selenium
1 18 (0.5)
1 9 (0.3)
1 27 (0.8)
Silver
1.7
0.9 (0.7)
2.6
Thallium
1 9.6 (0.2)
1 4.8 (0.1)
1 14.4 (0.3)
Zinc
0.5
0.3
0.8
a Mercury analysis only.
1 Detection limit when analyzed
by ICAP or GFAAS as shown in parentheses (see section 11.1.2).
2 Detection limit when anaylzed
by CVAAS, estimated for Back-half and Total Train. See sections
13.2 and 11.1.3. Note: Actual method in-stack detection limits may
vary from these values, as described in section 13.3.3.
Table 29-2 - Recommended Wavelengths for
ICAP Analysis
Analyte
Wavelength
(nm)
Aluminum (Al)
308.215
Antimony (Sb)
206.833
Arsenic (As)
193.696
Barium (Ba)
455.403
Beryllium
(Be)
313.042
Cadmium (Cd)
226.502
Chromium (Cr)
267.716
Cobalt (Co)
228.616
Copper (Cu)
328.754
Iron (Fe)
259.940
Lead (Pb)
220.353
Manganese
(Mn)
257.610
Nickel (Ni)
231.604
Phosphorus
(P)
214.914
Selenium (Se)
196.026
Silver (Ag)
328.068
Thallium (T1)
190,864
Zinc (Zn)
213,856
Table 29-3 - Applicable Techniques, Methods
and Minimization of Interferences for AAS Analysis
Metal
Technique
SW-846
1
Methods No.
Wavelength
(nm)
Interferences
Cause
Minimization
Fe
Aspiration
7380
248.3
Contamination
Great care taken to avoid
contamination.
Pb
Aspiration
7420
283.3
217.0 nm alternate
Background correction
required.
Pb
Furnace
7421
283.3
Poor recoveries
Matrix modifier, add 10 µl of
phosphorus acid to 1 ml of prepared sample in sampler cup.
Mn
Aspiration
7460
279.5
403.1 nm alternate
Background correction
required.
Ni
Aspiration
7520
232.0
352.4 nm alternate Fe, Co, and
Cr
Nonlinear response
Background correction
required. Matrix matching or nitrous-oxide/acetylene flame
Sample dilution or use 352.3 nm line
Se
Furnace
7740
196.0
Volatility
Spike samples and reference
materials and add nickel nitrate to minimize volatilization.
Adsorption & scatter
Background correction is
required and Zeeman background correction can be useful.
Ag
Aspiration
7760
328.1
Adsorption & scatter AgCl
insoluble
Background correction is
required. Avoid hydrochloric acid unless silver is in solution as a
chloride complex. Sample and standards monitored for aspiration
rate.
Tl
Aspiration
7840
276.8
Background correction is
required. Hydrochloric acid should not be used.
Tl
Furnace
7841
276.8
Hydrochloric acid or
chloride
Background correction is
required. Verify that losses are not occurring for volatilization
by spiked samples or standard addition; Palladium is a suitable
matrix modifier.
Zn
Aspiration
7950
213.9
High Si, Cu, & P
Contamination
Strontium removes Cu and
phosphate.
Great care taken to avoid contamination.
Sb
Aspiration
7040
217.6
1000 mg/ml Pb, Ni, Cu, or
acid
Use secondary wavelength of
231.1 nm; match sample & standards acid concentration or use
nitrous oxide/acetylene flame.
Sb
Furnace
7041
217.6
High Pb
Secondary wavelength or Zeeman
correction.
As
Furnace
7060
193.7
Arsenic Volatilization
Aluminum
Spike samples and add nickel
nitrate solution to digestates prior to analysis. Use Zeeman
background correction.
Ba
Aspiration
7080
553.6
Calcium
Barium Ionization
High hollow cathode current
and narrow band set.
2 ml of KCl per 100 m1 of sample.
Be
Aspiration
7090
234.9
500 ppm Al. High Mg and
Si
Add 0.1% fluoride.
Be
Furnace
7091
234.9
Be in optical path
Optimize parameters to
minimize effects.
Cd
Aspiration
7130
228.8
Absorption and light
scattering
Background correction is
required.
Cd
Furnace
7131
228.8
As above
Excess Chloride
Pipet Tips
As above.
Ammonium phosphate used as a matrix modifier.
Use cadmium-free tips.
Cr
Aspiration
7190
357.9
Alkali metal
KCl ionization suppressant in
samples and standards - Consult mfgs' literature.
Co
Furnace
7201
240.7
Excess chloride
Use Method of Standard
Additions.
Cr
Furnace
7191
357.9
200 mg/L Ca and P
All calcium nitrate for a know
constant effect and to eliminate effect of phosphate.
Cu
Aspiration
7210
324.7
Absorption and Scatter
Consult manufacturer's
manual.
1 Refer to EPA publication SW-846
(Reference 2 in section 16.0).
Method 30A -
Determination of Total Vapor Phase Mercury Emissions From
Stationary Sources (Instrumental Analyzer Procedure) 1.0 Scope and
Application What Is Method 30A?
Method 30A is a procedure for measuring total vapor phase
mercury (Hg) emissions from stationary sources using an
instrumental analyzer. This method is particularly appropriate for
performing emissions testing and for conducting relative accuracy
test audits (RATAs) of mercury continuous emissions monitoring
systems (Hg CEMS) and sorbent trap monitoring systems at coal-fired
combustion sources. Quality assurance and quality control
requirements are included to assure that you, the tester, collect
data of known and acceptable quality for each testing site. This
method does not completely describe all equipment, supplies, and
sampling procedures and analytical procedures you will need but
refers to other test methods for some of the details. Therefore, to
obtain reliable results, you should also have a thorough knowledge
of these additional methods which are also found in appendices A-1
and A-3 to this part:
(a) Method 1 - Sample and Velocity Traverses for Stationary
Sources.
(b) Method 4 - Determination of Moisture Content in Stack
Gases.
1.1 Analytes. What does this method determine? This method is
designed to measure the mass concentration of total vapor phase Hg
in flue gas, which represents the sum of elemental Hg (Hg 0) and
oxidized forms of Hg (Hg+2), in mass concentration units of
micrograms per cubic meter (µg/m 3).
Analyte
CAS No.
Sensitivity
Elemental Hg (Hg
0)
7439-97-6
Typically <2% of
Calibration Span.
Oxidized Hg
(Hg+2)
(Same).
1.2 Applicability. When is this method required? Method 30A is
offered as a reference method for emission testing and for RATAs of
Hg CEMS and sorbent trap monitoring systems at coal-fired boilers.
Method 30A may also be specified for other source categories in the
future, either by New Source Performance Standards (NSPS), National
Emission Standards for Hazardous Air Pollutants (NESHAP), emissions
trading programs, State Implementation Plans (SIP), or operating
permits that require measurement of Hg concentrations in stationary
source emissions to determine compliance with an applicable
emission standard or limit, or to conduct RATAs of Hg CEMS and
sorbent trap monitoring systems.
1.3 Data Quality Objectives (DQO). How good must my collected
data be? Method 30A has been designed to provide data of high and
known quality for Hg emission testing and for relative accuracy
testing of Hg monitoring systems including Hg CEMS and sorbent trap
monitoring systems. In these and other applications, the principle
objective is to ensure the accuracy of the data at the actual
emission levels encountered. To meet this objective, calibration
standards prepared according to an EPA traceability protocol must
be used and measurement system performance tests are required.
2.0 Summary of Method
In this method, a sample of the effluent gas is continuously
extracted and conveyed to an analyzer capable of measuring the
total vapor phase Hg concentration. Elemental and oxidized mercury
(i.e., Hg 0 and Hg+2) may be measured separately or simultaneously
but, for purposes of this method, total vapor phase Hg is the sum
of Hg 0 and Hg+2. You must meet the performance requirements of
this method (i.e., system calibration, interference testing,
dynamic spiking, and system integrity/drift checks) to validate
your data. The dynamic spiking requirement is deferred until
January 1, 2009.
3.0 Definitions
3.1 Calibration Curve means the relationship between an
analyzer's response to the injection of a series of calibration
gases and the actual concentrations of those gases.
3.2 Calibration Gas means a gas standard containing Hg 0
or HgCl2 at a known concentration that is produced and certified in
accordance with an EPA traceability protocol for certification of
Hg calibration standards.
3.2.1 Zero Gas means a calibration gas with a
concentration that is below the level detectable by the measurement
system.
3.2.2 Low-Level Gas means a calibration gas with a
concentration that is 10 to 30 percent of the calibration span.
3.2.3 Mid-Level Gas means a calibration gas with a
concentration that is 40 to 60 percent of the calibration span.
3.2.4 High-Level Gas means a calibration gas whose
concentration is equal to the calibration span.
3.3 Converter means a device that reduces oxidized
mercury (Hg+2) to elemental mercury (Hg 0).
3.4 Calibration Span means the upper limit of valid
instrument response during sampling. To the extent practicable the
measured emissions are to be between 10 and 100 percent of the
selected calibration span (i.e., the measured emissions
should be within the calibrated range determined by the Low- and
High-Level gas standards). It is recommended that the calibration
span be at least twice the native concentration to accommodate the
dynamic spiking procedure.
3.5 Centroidal Area means the central area that has the
same shape as the stack or duct cross section and is no greater
than one percent of the stack or duct total cross-sectional
area.
3.6 Data Recorder means the equipment that permanently
records the concentrations reported by the analyzer.
3.7 Drift Check means the test to determine the
difference between the measurement system readings obtained in a
post-run system integrity check and the prior pre-run system
integrity check at a specific calibration gas concentration level
(i.e., zero, mid-level, or high-level).
3.8 Dynamic Spiking means a procedure in which a known
mass or concentration of vapor phase HgCl2 is injected into the
probe sample gas stream at a known flow rate, in order to assess
the effects of the flue gas matrix on the accuracy of the
measurement system.
3.9 Gas Analyzer means the equipment that detects the
total vapor phase Hg being measured and generates an output
proportional to its concentration.
3.10 Interference Test means the test to detect analyzer
responses to compounds other than Hg, usually gases present in the
measured gas stream, that are not adequately accounted for in the
calibration procedure and may cause measurement bias.
3.11 Measurement System means all of the equipment used
to determine the Hg concentration. The measurement system may
generally include the following major subsystems: sample
acquisition, Hg+2 to Hg 0 converter, sample transport, sample
conditioning, flow control/gas manifold, gas analyzer, and data
recorder.
3.12 Native Concentration means the total vapor phase Hg
concentration in the effluent gas stream.
3.13 NIST means the National Institute of Standards and
Technology, located in Gaithersburg, Maryland.
3.14 Response Time means the time it takes for the
measurement system, while operating normally at its target sample
flow rate or dilution ratio, to respond to a known step change in
gas concentration (from a low-level to a high-level gas) and to
read within 5 percent of the stable high-level gas response.
3.15 Run means a series of gas samples taken successively
from the stack or duct. A test normally consists of a specific
number of runs.
3.16 System Calibration Error means the difference
between the measured concentration of a low-, mid-, or high-level
Hg 0 calibration gas and the certified concentration of the gas
when it is introduced in system calibration mode.
3.17 System Calibration Mode means introducing the
calibration gases into the measurement system at the probe,
upstream of all sample conditioning components.
3.18 Test refers to the series of runs required by the
applicable regulation.
4.0 Interferences
Interferences will vary among instruments and potential
instrument-specific spectral and matrix interferences must be
evaluated through the interference test and the dynamic spiking
tests.
5.0 Safety What safety measures should I consider when using this
method?
This method may require you to work with hazardous materials and
in hazardous conditions. You are encouraged to establish safety
procedures before using the method. Among other precautions, you
should become familiar with the safety recommendations in the gas
analyzer user's manual. Occupational Safety and Health
Administration (OSHA) regulations concerning use of compressed gas
cylinders and noxious gases may apply.
6.0 Equipment and Supplies
6.1 What do I need for the measurement system? This method is
intended to be applicable to multiple instrumental technologies.
You may use any equipment and supplies that meet the following
specifications.
6.1.1 All wetted sampling system components, including probe
components prior to the point at which the calibration gas is
introduced, must be chemically inert to all Hg species. Materials
such as perfluoroalkoxy (PFA) Teflon TM, quartz, treated stainless
steel (SS) are examples of such materials. [Note: These materials
of construction are required because components prior to the
calibration gas injection point are not included in the system
calibration error, system integrity, and interference tests.]
6.1.2 The interference, system calibration error, system
integrity, drift and dynamic spiking test criteria must all be met
by the system used.
6.1.3 The system must be capable of measuring and controlling
sample flow rate.
6.1.4 All system components prior to the Hg+2 to Hg 0 converter
must be maintained at a sample temperature above the acid gas dew
point.
6.2 Measurement System Components. Figure 30A-1 in section 17.0
is an example schematic of a Method 30A measurement system.
6.2.1 Sample Probe. The probe must be made of the appropriate
materials as noted in section 6.1.1, heated when necessary (see
section 6.1.4), configured with ports for introduction of
calibration and spiking gases, and of sufficient length to traverse
all of the sample points.
6.2.2 Filter or Other Particulate Removal Device. The filter or
other particulate removal device is considered to be a part of the
measurement system, must be made of appropriate materials as noted
in section 6.1.1, and must be included in all system tests.
6.2.3 Sample Line. The sample line that connects the probe to
the converter, conditioning system and analyzer must be made of
appropriate materials as noted in section 6.1.1.
6.2.4 Conditioning Equipment. For dry basis measurements, a
condenser, dryer or other suitable device is required to remove
moisture continuously from the sample gas. Any equipment needed to
heat the probe, or sample line to avoid condensation prior to the
moisture removal component is also required. For wet basis systems,
you must keep the sample above its dew point either by: (1) Heating
the sample line and all sample transport components up to the inlet
of the analyzer (and, for hot-wet extractive systems, also heating
the analyzer) or (2) by diluting the sample prior to analysis using
a dilution probe system. The components required to do either of
the above are considered to be conditioning equipment.
6.2.5 Sampling Pump. A pump is needed to push or pull the sample
gas through the system at a flow rate sufficient to minimize the
response time of the measurement system. If a mechanical sample
pump is used and its surfaces are in contact with the sample gas
prior to detection, the pump must be leak free and must be
constructed of a material that is non-reactive to the gas being
sampled (see section 6.1.1). For dilution-type measurement systems,
an ejector pump (eductor) may be used to create a sufficient vacuum
that sample gas will be drawn through a critical orifice at a
constant rate. The ejector pump may be constructed of any material
that is non-reactive to the gas being sampled.
6.2.6 Calibration Gas System(s). One or more systems may be
needed to introduce calibration gases into the measurement system.
A system should be able to flood the sampling probe sufficiently to
prevent entry of gas from the effluent stream.
6.2.7 Dynamic Spiking Port. For the purposes of the dynamic
spiking procedure described in section 8.2.7, the measurement
system must be equipped with a port to allow introduction of the
dynamic spike gas stream with the sample gas stream, at a point as
close as possible to the inlet of the probe so as to ensure
adequate mixing. The same port used for system calibrations and
calibration error checks may be used for dynamic spiking
purposes.
6.2.8 Sample Gas Delivery. The sample line may feed directly to
a converter, to a by-pass valve (for speciating systems), or to a
sample manifold. All valve and/or manifold components must be made
of material that is non-reactive to the gas sampled and the
calibration gas, and must be configured to safely discharge any
excess gas.
6.2.9 Hg Analyzer. An instrument is required that continuously
measures the total vapor phase Hg in the gas stream and meets the
applicable specifications in section 13.0.
6.2.10 Data Recorder. A recorder, such as a computerized data
acquisition and handling system (DAHS), digital recorder, strip
chart, or data logger, is required for recording measurement
data.
6.3 Moisture Measurement System. If correction of the measured
Hg emissions for moisture is required (see section 8.5), either
Method 4 in appendix A-3 to this part or other moisture measurement
methods approved by the Administrator will be needed to measure
stack gas moisture content.
7.0 Reagents and Standards
7.1 Calibration Gases. What calibration gases do I need? You
will need calibration gases of known concentrations of Hg 0 and
HgCl2. Special reagents and equipment may be required to prepare
the HgCl 2 gas standards (e.g., a NIST-traceable solution of HgCl2
and a gas generator equipped with mass flow controllers).
The following calibration gas concentrations are required:
7.1.1 High-Level Gas. Equal to the selected calibration
span.
7.1.2 Mid-Level Gas. 40 to 60 percent of the calibration
span.
7.1.3 Low-Level Gas. 10 to 30 percent of the calibration
span.
7.1.4 Zero Gas. No detectable Hg.
7.1.5 Dynamic Spike Gas. The exact concentration of the HgCl2
calibration gas used to perform the pre-test dynamic spiking
procedure described in section 8.2.7 depends on the native Hg
concentration in the stack The spike gas must produce a spiked
sample concentration above the native concentration, as specified
in section 8.2.7.2.2.
7.2 Interference Test. What reagents do I need for the
interference test? Use the appropriate test gases listed in Table
30A-3 in section 17.0 (i.e., the potential interferents for the
source to be tested, as identified by the instrument manufacturer)
to conduct the interference check. These gases need not be of
protocol gas quality.
8.0 Sample Collection Emission Test Procedure
Figure 30A-2 in section 17.0 presents an overview of the test
procedures required by this method. Since you may choose different
options to comply with certain performance criteria, you must
identify the specific options and associated frequencies you select
and document your results in regard to the performance
criteria.
8.1 Selection of Sampling Sites and Sampling Points. What
sampling site and sampling points do I select?
8.1.1 When this method is used solely for Hg emission testing
(e.g., to determine compliance with an emission standard or limit),
use twelve sampling points located according to Table 1-1 or Table
1-2 of Method 1 in appendix A-1 to this part. Alternatively, you
may conduct a stratification test as described in section 8.1.3 to
determine the number and location of the sampling points.
8.1.2 When this method is used for relative accuracy testing of
a Hg CEMS or sorbent trap monitoring system, follow the sampling
site selection and sampling point layout procedures for gas monitor
RATA testing described in the appropriate performance specification
or applicable regulation (e.g., Performance Specification 2,
section 8.1.3 of appendix B to this part or section 6.5.6 of
appendix A to part 75 of this chapter), with one exception. If you
elect to perform stratification testing as part of the sampling
point selection process, perform the testing in accordance with
section 8.1.3 of this method (see also “Summary Table of QA/QC
Requirements” in section 9.0).
8.1.3 Determination of Stratification. If you elect to perform
stratification testing as part of the sampling point selection
process and the test results show your effluent gas stream to be
unstratified or minimally stratified, you may be allowed to sample
at fewer points or at different points than would otherwise be
required.
8.1.3.1 Test Procedure. To test for stratification, use a probe
of appropriate length to measure the total vapor phase Hg
concentration at twelve traverse points located according to Table
1-1 or Table 1-2 of Method 1 in appendix A-1 to this part.
Alternatively, for a sampling location where stratification is
expected (e.g., after a wet scrubber or at a point where dissimilar
gas streams are combined together), if a 12-point Hg stratification
test has been previously performed at that location and the results
of the test showed the location to be minimally stratified or
unstratified according to the criteria in section 8.1.3.2, you may
perform an abbreviated 3-point or 6-point Hg stratification test at
the points specified in section 6.5.6.2(a) of appendix A to part 75
of this chapter in lieu of performing the 12-point test. Sample for
a minimum of twice the system response time (see section 8.2.6) at
each traverse point. Calculate the individual point and mean Hg
concentrations.
8.1.3.2 Acceptance Criteria and Sampling Point Location.
8.1.3.2.1 If the Hg concentration at each traverse point differs
from the mean concentration for all traverse points by no more
than: (a) ±5 percent of the mean concentration; or (b) ±0.2 µg/m 3
(whichever is less restrictive), the gas stream is considered to be
unstratified and you may collect samples from a single point that
most closely matches the mean.
8.1.3.2.2 If the 5 percent or 0.2 µg/m 3 criterion in section
8.1.3.2.1 is not met, but the Hg concentration at each traverse
point differs from the mean concentration for all traverse points
by no more than: (a)±10 percent of the mean; or (b)±0.5 µg/m 3
(whichever is less restrictive), the gas stream is considered to be
minimally stratified, and you may take samples from three points,
provided the points are located on the measurement line exhibiting
the highest average Hg concentration during the stratification
test. If the stack diameter (or equivalent diameter, for a
rectangular stack or duct) is greater than 2.4 meters (7.8 ft),
locate the three sampling points at 0.4, 1.0, and 2.0 meters from
the stack or duct wall. Alternatively, if a RATA required by part
75 of this chapter is being conducted, you may locate the three
points at 4.4, 14.6, and 29.6 percent of the duct diameter, in
accordance with Method 1 in appendix A-1 to this part. For stack or
duct diameters of 2.4 meters (7.8 ft) or less, locate the three
sampling points at 16.7, 50.0, and 83.3 percent of the measurement
line.
8.1.3.2.3 If the gas stream is found to be stratified because
the 10 percent or 0.5 µg/m 3 criterion in section 8.1.3.2.2 is not
met, then either locate three sampling points at 16.7, 50.0, and
83.3 percent of the measurement line that exhibited the highest
average Hg concentration during the stratification test, or locate
twelve traverse points for the test in accordance with Table 1-1 or
Table 1-2 of Method 1 in appendix A-1 to this part; or, if a RATA
required by part 75 of this chapter is being conducted, locate six
Method 1 points along the measurement line that exhibited the
highest average Hg concentration.
8.1.3.3 Temporal Variations. Temporal variations in the source
Hg concentration during a stratification test may complicate the
determination of stratification. If temporal variations are a
concern, you may use the following procedure to normalize the
stratification test data. A second Hg measurement system, i.e.,
either an installed Hg CEMS or another Method 30A system, is
required to perform this procedure. Position the sampling probe of
the second Hg measurement system at a fixed point in the stack or
duct, at least one meter from the stack or duct wall. Then, each
time that the Hg concentration is measured at one of the
stratification test points, make a concurrent measurement of Hg
concentration at the fixed point. Normalize the Hg concentration
measured at each traverse point, by multiplying it by the ratio of
CF,avg to CF, where CF is the corresponding fixed-point Hg
concentration measurement, and CF,avg is the average of all of the
fixed-point measurements over the duration of the stratification
test. Evaluate the results of the stratification test according to
section 8.1.3.2, using the normalized Hg concentrations.
8.1.3.4 Stratification Testing Exemption. Stratification testing
need not be performed at a test location where it would otherwise
be required to justify using fewer sample points or different
sample points, if the owner or operator documents that the Hg
concentration in the stack gas is expected to be 3 µg/m 3 or less
at the time of a Hg monitoring system RATA or an Hg emissions test.
To demonstrate that a particular test location qualifies for the
stratification testing exemption, representative Hg emissions data
must be collected just prior to the RATA or emissions test. At
least one hour of Hg concentration data is required for the
demonstration. The data used for the demonstration shall be
recorded at process operating conditions that closely approximate
the operating conditions that will exist during the RATA or
emissions test. It is recommended that collection of the
demonstration data be integrated with the on-site pretest
procedures required by the reference method being used for the RATA
or emissions test (whether this method or another approved Hg
reference method is used). Quality-assured data from an installed
Hg monitoring system may also be used for the demonstration. If a
particular test location qualifies for the stratification testing
exemption, sampling shall be performed at three points, as
described in section 8.1.3.2.2 of this method. The owner or
operator shall fully document the method used to collect the
demonstration data and shall keep this documentation on file with
the data from the associated RATA or Hg emissions test.
8.1.3.5 Interim Alternative Stratification Test Procedures. In
the time period between the effective date of this method and
January 1, 2009, you may follow one of the following two
procedures. Substitute a stratification test for sulfur dioxide
(SO2) for the Hg stratification test described in section 8.1.3.1.
If this option is chosen, follow the test procedures in section
6.5.6.1 of appendix A to part 75 of this chapter. Evaluate the test
results and determine the sampling point locations according to
section 6.5.6.3 of appendix A to part 75 of this chapter. If the
sampling location is found to be minimally stratified or
unstratified for SO2, it shall be considered minimally stratified
or unstratified for Hg. Alternatively, you may forgo stratification
testing, assume the gas stream is minimally stratified, and sample
at three points as described in section 8.1.3.2.2 of this
method.
8.2 Initial Measurement System Performance Tests. What initial
performance criteria must my system meet before I begin sampling?
Before measuring emissions, perform the following procedures:
(a) Interference Test;
(b) Calibration Gas Verification;
(c) Measurement System Preparation;
(d) 3-Point System Calibration Error Test;
(e) System Integrity Check;
(f) Measurement System Response Time Test; and
(g) Dynamic Spiking Test.
8.2.1 Interference Test (Optional). Your measurement system
should be free of known interferences. It is recommended that you
conduct this interference test of your measurement system prior to
its initial use in the field to verify that the candidate test
instrument is free from inherent biases or interferences resulting
from common combustion emission constituents. If you have multiple
measurement systems with components of the same make and model
numbers, you need only perform this interference check on one
system and you may also rely on an interference test conducted by
the manufacturer on a system having components of the same make and
model(s) of the system that you use. The interference test
procedure is found in section 8.6 of this method.
8.2.2 Calibration Gas Verification. How must I verify the
concentrations of my calibration gases?
8.2.2.1 Cylinder Gas Standards. When cylinder gas standards are
used for Hg 0, obtain a certificate from the gas manufacturer and
confirm that the documentation includes all information required by
an EPA traceability protocol (see section 16). Confirm that the
manufacturer certification is complete and current. Ensure that the
calibration gas certifications have not expired.
8.2.2.2 Other Calibration Standards. All other calibration
standards for HgCl2 and Hg 0, such as gas generators, must meet the
requirements of an EPA traceability protocol (see section 16), and
the certification procedures must be fully documented in the test
report.
8.2.2.3 Calibration Span. Select the calibration span (i.e.,
high-level gas concentration) so that the measured source emissions
are 10 to 100 percent of the calibration span. This requirement is
waived for applications in which the Hg concentrations are
consistently below 1 µg/m 3; however, the calibration span for
these low-concentration applications shall not exceed 5 µg/m 3.
8.2.3 Measurement System Preparation. How do I prepare my
measurement system for use? Assemble, prepare, and precondition the
measurement system according to your standard operating procedure.
Adjust the system to achieve the correct sampling rate or dilution
ratio (as applicable). Then, conduct a 3-point system calibration
error test using Hg 0 as described in section 8.2.4, an initial
system integrity check using HgCl2 and a zero gas as described in
section 8.2.5, and a pre-test dynamic spiking test as described in
section 8.2.7.
8.2.4 System Calibration Error Test. Conduct a 3-point system
calibration error test before the first test run. Use Hg 0
standards for this test. Introduce the low-, mid-, and high-level
calibration gases in any order, in system calibration mode, unless
you desire to determine the system response time during this test,
in which case, inject the gases such that the high-level injection
directly follows the low-level injection. For non-dilution systems,
you may adjust the system to maintain the correct flow rate at the
analyzer during the test, but you may not make adjustments for any
other purpose. For dilution systems, you must operate the
measurement system at the appropriate dilution ratio during all
system calibration error checks, and you may make only the
adjustments necessary to maintain the proper ratio. After each gas
injection, wait until a stable response has been obtained. Record
the analyzer's final, stable response to each calibration gas on a
form similar to Table 30A-1 in section 17.0. For each calibration
gas, calculate the system calibration error using Equation 30A-1 in
section 12.2. The calibration error specification in section 13.1
must be met for the low-, mid-, and high-level gases. If the
calibration error specification is not met for all three gases,
take corrective action and repeat the test until an acceptable
3-point calibration is achieved.
8.2.5 System Integrity Check. Perform a two-point system
integrity check before the first test run. Use the zero gas and
either the mid- or high-level HgCl2 calibration gas for the check,
whichever one best represents the total vapor phase Hg
concentration levels in the stack. Record the data on a form
similar to Table 30A-2 in section 17.0. The system integrity check
specification in section 13.2 must be met for both the zero gas and
the mid- or high-level gas. If the system integrity specification
is not met for both gases, take corrective action and repeat the
test until an acceptable system integrity check is achieved.
8.2.6 Measurement System Response Time. The measurement system
response time is used to determine the minimum sampling time for
each sampling point and is equal to the time that is required for
the measured Hg concentration to increase from the stable low-level
calibration gas response to a value within 5 percent of the stable
high-level calibration gas response during the system calibration
error test in section 8.2.4. Round off the measured system response
time to the nearest minute.
8.2.7 Dynamic Spiking Test. You must perform dynamic spiking
prior to the first test run to validate your test data. The purpose
of this procedure is to demonstrate that the site-specific flue gas
matrix does not adversely affect the accuracy of the measurement
system. The specifications in section 13.5 must be met to validate
your data. If these specifications are not met for the pre-test
dynamic spiking, you may not proceed with the test until
satisfactory results are obtained. For the time period between the
effective date of this method and January 1, 2009, the dynamic
spiking requirement is waived.
8.2.7.1 How do I perform dynamic spiking? Dynamic spiking is a
gas phase application of the method of standard additions, which
involves injecting a known quantity of Hg into the measurement
system upstream of all sample conditioning components, similar to
system calibration mode, except the probe is not flooded and the
resulting sample stream includes both effluent gas and the spike
gas. You must follow a written procedure that details how the spike
is added to the system, how the spike dilution factor (DF) is
measured, and how the Hg concentration data are collected and
processed.
8.2.7.2 Spiking Procedure Requirements.
8.2.7.2.1 Spiking Gas Requirements. The spike gas must also be a
HgCl2 calibration gas certified by an EPA traceability protocol.
You must choose concentrations that can produce the target levels
while being injected at a volumetric flow rate that is ≤20 percent
of the total volumetric flow rate through the measurement system
(i.e., sample flow rate plus spike gas flow rate).
8.2.7.2.2 Target Spiking Level. The target level for spiking
must be 150 to 200 percent of the native Hg concentration; however,
if the native Hg concentration is <1 µg/m 3, set the target
level to add between 1 and 4 µg/m 3 Hg+2 to the native
concentration. Use Equation 30A-5 in section 12.5 to calculate the
acceptable range of spike gas concentrations at the target level.
Then select a spike gas concentration in that range.
8.2.7.2.3 Spike Injections. You must inject spikes in such a
manner that the spiking does not alter the total volumetric sample
system flow rate and dilution ratio (if applicable). You must
collect at least 3 data points, and the relative standard deviation
(RSD) specification in section 13.5 must be met. Each data point
represents a single spike injection, and pre- and post-injection
measurements of the native Hg concentration (or diluted native
concentration, as applicable) are required for each spike
injection.
8.2.7.2.4 Spike Dilution Factor (DF). For each spike injection,
DF, the dilution factor must be determined. DF is the ratio of the
total volumetric flow rate of gas through the measurement system to
the spike gas flow rate. This factor must be ≥5. The spiking mass
balance calculation is directly dependent on the accuracy of the DF
determination. As a result, high accuracy total volumetric flow
rate and spike gas flowrate measurements are required. These flow
rates may be determined by direct or indirect measurement.
Calibrated flow meters, venturies, orifices or tracer gas
measurements are examples of potential flow measurement
techniques.
8.2.7.2.5 Concentrations. The measurement system must record
total vapor phase Hg concentrations continuously during the dynamic
spiking procedure. It is possible that dynamic spiking at a level
close to 200 percent of the native Hg concentration may cause the
measured Hg concentration to exceed the calibration span value.
Avoid this by choosing a lower spiking level or by recalibration at
a higher span. The measurements shall not exceed 120 percent of the
calibration span. The “baseline” measurements made between spikes
may represent the native Hg concentration (if spike gas flow is
stopped between injections) or the native Hg concentration diluted
by blank or carrier gas flowing at the same rate as the spike gas
(if gas flow cannot be stopped between injections). Each baseline
measurement must include at least 4 readings or 1 minute (whichever
is greater) of stable responses. Use Equation 30A-10 or 30A-11 in
section 12.10 (as applicable) to convert baseline measurements to
native concentration.
8.2.7.2.6 Recovery. Calculate spike recoveries using Equation
30A-7 in section 12.7. Mass recoveries may be calculated from
stable responses based on injected mass flows or from integrated
response peaks based on total mass injected. Calculate the mean and
RSD for the three (or more) spike injections and compare to the
specifications in section 13.5.
8.2.7.2.7 Error Adjustment Option. You may adjust the
measurement data collected during dynamic spiking for the system
calibration error using Equation 30A-3 in section 12. To do this,
perform the initial system integrity check prior to the dynamic
spiking test, and perform another system integrity check following
the dynamic spiking test and before the first test run. If you
choose this option, you must apply Equation 30A-3 to both the
spiked sample concentration measurement (Css) and the baseline or
native concentration measurement (Cnative), each substituted in
place of Cavg in the equation.
8.2.7.3 Example Spiking Procedure Using a Hot Vapor Calibration
Source Generator.
(a) Introduce the spike gas into the probe using a hot vapor
calibration source generator and a solution of HgCl2 in dilute HC1
and HNO3. The calibrator uses a mass flow controller (accurate
within 2 percent) to measure the gas flow, and the solution feed is
measured using a top-loading balance accurate to 0.01g. The
challenges of injecting oxidized Hg may make it impractical to stop
the flow of gas between spike injections. In this case, operate the
hot vapor calibration source generator continuously during the
spiking procedure, swapping blank solutions for HgCl2 solutions
when switching between spiking and baseline measurements.
(b) If applicable, monitor the measurement system to make sure
the total sampling system flow rate and the sample dilution ratio
do not change during this procedure. Record all data on a data
sheet similar to Table 30A-5 in section 17.0. If the Hg measurement
system design makes it impractical to measure the total volumetric
flow rate through the system, use a spike gas that includes a
tracer for measuring the dilution factor, DF (see Equation 30A-9 in
section 12.9). Allow the measurements to stabilize between each
spike injection, average the pre- and post-injection baseline
measurements, and calculate the native concentration. If this
measurement shifts by more than 5 percent during any injection, it
may be necessary to discard that data point and repeat the
injection to achieve the required RSD among the injections. If the
spikes persistently show poor repeatability, or if the recoveries
are not within the range specified in section 13.5, take corrective
action.
8.2.8 Run Validation. How do I confirm that each run I conduct
is valid?
8.2.8.1 System Integrity Checks.
(a) Before and after each test run, perform a two-point system
integrity check using the same procedure as the initial system
integrity check described in section 8.2.5. You may use data from
that initial system integrity check as the pre-run data for the
first test run, provided it is the most recent system integrity
check done before the first run. You may also use the results of a
successful post-run system integrity check as the pre-run data for
the next test run. Do not make any adjustments to the measurement
system during these checks, other than to maintain the target
calibration gas flow rate and the proper dilution ratio.
(b) As a time-saving alternative, you may, at the risk of
invalidating multiple test runs, skip one or more integrity checks
during a test day. Provided there have been no auto-calibrations or
other instrument alterations, a single integrity check may suffice
as a post-run check to validate (or invalidate) as many consecutive
test runs as can be completed during a single test day. All
subsequent test days must begin with a pre-run system integrity
check subject to the same performance criteria and corrective
action requirements as a post-run system integrity check.
(c) Each system integrity check must meet the criteria for
system integrity checks in section 13.2. If a post-run system
integrity check is failed, all test runs since the last passed
system integrity check are invalid. If a post-run or a pre-run
system integrity check is failed, you must take corrective action
and pass another 3-point Hg 0 system calibration error test
(Section 8.2.4) followed by another system integrity check before
conducting any additional test runs. Record the results of the pre-
and post-run system integrity checks on a form similar to Table
30A-2 in section 17.0.
8.2.8.2 Drift Check. Using the data from the successful pre- and
post-run system integrity checks, calculate the zero and upscale
drift, using Equation 30A-2 in section 12.3. Exceeding the section
13.3 specification does not invalidate the run, but corrective
action must be taken and a new 3-point Hg 0 system calibration
error test and a system integrity check must be passed before any
more runs are made.
8.3 Dilution-Type Systems - Special Considerations. When a
dilution-type measurement system is used, there are three important
considerations that must be taken into account to ensure the
quality of the emissions data. First, the critical orifice size and
dilution ratio must be selected properly so that the sample dew
point will be below the sample line and analyzer temperatures.
Second, a high-quality, accurate dilution controller must be used
to maintain the correct dilution ratio during sampling. The
dilution controller should be capable of monitoring the dilution
air pressure, orifice upstream pressure, eductor vacuum, and sample
flow rates. Third, differences between the molecular weight of
calibration gas mixtures, dilution air, and the stack gas molecular
weight must be considered because these can affect the dilution
ratio and introduce measurement bias.
8.4 Sampling.
(a) Position the probe at the first sampling point. Allow the
system to flush and equilibrate for at least two times the
measurement system response time before recording any data. Then,
traverse and record measurements at all required sampling points.
Sample at each traverse point for an equal length of time,
maintaining the appropriate sample flow rate or dilution ratio (as
applicable). For all Hg instrumental method systems, the minimum
sampling time at each sampling point must be at least two times the
system response time, but not less than 10 minutes. For
concentrating systems, the minimum sampling time must also include
at least 4 concentration measurement cycles.
(b) After recording data for the appropriate period of time at
the first traverse point, you may move the sample probe to the next
point and continue recording, omitting the requirement to allow the
system to equilibrate for two times the system response time before
recording data at the subsequent traverse points. You must,
however, sample at this and all subsequent traverse points for the
required minimum amount of time specified in this section. If you
must remove the probe from the stack for any reason, you must again
allow the sampling system to equilibrate for at least two times the
system response time prior to resuming data recording.
(c) If at any point the measured Hg concentration exceeds the
calibration span value, you must at a minimum identify and report
this as a deviation from the method. Depending on the data quality
objectives of the test, this event may require corrective action
before proceeding. If the average Hg concentration for any run
exceeds the calibration span value, the run is invalidated.
8.5 Moisture Correction. If the moisture basis (wet or dry) of
the measurements made with this method is different from the
moisture basis of either: (1) The applicable emission limit; or (2)
a Hg CEMS or sorbent trap monitoring system being evaluated for
relative accuracy, you must determine the moisture content of the
flue gas and correct the measured gas concentrations to a dry basis
using Method 4 in appendix A-3 of this part or other appropriate
methods, subject to the approval of the Administrator.
8.6 Optional Interference Test Procedure.
(a) Select an appropriate calibration span that reflects the
source(s) to be tested and perform the interference check at 40
percent of the lowest calibration span value anticipated, e.g., 10
µg/m 3. Alternatively, successfully conducting the interference
test at an absolute Hg concentration of 2 µg/m 3 will demonstrate
performance for an equivalent calibration span of 5 µg/m 3, the
lowest calibration span allowed for Method 30A testing. Therefore,
performing the interference test at the 2 µ/m 3 level will serve to
demonstrate acceptable performance for all calibration spans
greater than or equal to 5 µg/m 3.
(b) Introduce the interference test gases listed in Table 30A-3
in section 17.0 into the measurement system separately or as a
mixture. The interference test gases HCl and NO must be introduced
as a mixture. The interference test gases must be introduced into
the sampling system at the probe such that the interference gas
mixtures pass through all filters, scrubbers, conditioners, and
other components as would be configured for normal sampling.
(c) The interference test must be performed using HgCl2, and
each interference test gas (or gas mixture) must be evaluated in
triplicate. This is accomplished by measuring the Hg response first
with only the HgCl2 gas present and then when adding the
interference test gas(es) while maintaining the HgCl2 concentration
of the test stream constant. It is important that the equipment
used to conduct the interference test be of sufficient quality so
as to be capable of blending the HgCl2 and interference gases while
maintaining the Hg concentration constant. Gas blending system or
manifolds may be used.
(d) The duration of each test should be for a sufficient period
of time to ensure the Hg measurement system surfaces are
conditioned and a stable output is obtained. Measure the Hg
response of the analyzer to these gases in µg/m3. Record the
responses and determine the overall interference response using
Table 30A-4 in section 17.0 and the equations presented in section
12.11. The specification in section 13.4 must be met.
(e) A copy of these data, including the date completed and a
signed certification, must be included with each test report. The
intent of this test is that the interference test results are
intended to be valid for the life of the system. As a result, the
Hg measurement system should be operated and tested in a
configuration consistent with the configuration that will be used
for field applications. However, if the system used for field
testing is not consistent with the system that was
interference-tested, the interference test must be repeated before
it is used for any field applications. Examples of such conditions
include, but are not limited to: major changes in dilution ratio
(for dilution based systems), changes in catalyst materials,
changes in filtering device design or materials, changes in probe
design or configuration, and changes in gas conditioning materials
or approaches.
9.0 Quality Control What quality control measures must I take?
The table which follows is a summary of the mandatory,
suggested, and alternative quality assurance and quality control
measures and the associated frequency and acceptance criteria. All
of the QC data, along with the run data, must be documented and
included in the test report.
Summary Table of QA/QC Requirements
Status 1
Process or element
QA/QC specification
Acceptance criteria
Checking frequency
S
Identify Data User
Regulatory Agency or other
primary end user of data
Before designing test.
M
Analyzer Design
Analyzer range
Sufficiently >high-level
gas to allow determination of system calibration error
Each system integrity check
(if it better represents Cnative than the mid level gas).
M
Mid-level HgCl2
40 to 60% of calibration
span
Each system gas integrity
check (if it better represents Cnative than the high level
gas).
M
Zero gas
Each system integrity
check.
M
Dynamic spike gas (Cnative ≥1
µg/m 3)
A high-concentration HgCl2
gas, used to produce a spiked sample concentration that is 150 to
200% of the native concentration
Pre-test; dynamic spiking not
required until 1/1/09.
M
Dynamic spike gas (Cnative
<1 µg/m 3)
A high-concentration HgCl2
gas, used to produce a spiked sample concentration that is 1 to 2
µg/m 3 above the native concentration
Pre-test; dynamic spiking not
required until 1/1/09.
S
Data Recorder Design
Data resolution
≤0.5% of full-scale
Manufacturer design.
M
Sample Extraction
Probe material
Inert to sample constituents
(e.g., PFA Teflon, or quartz if stack >500 °F)
Each run.
M
Sample Extraction
Probe, filter and sample line
temperature
For dry-basis analyzers, keep
sample above the dew point, by heating prior to moisture
removal
For wet-basis analyzers, keep sample above dew point at all times,
by heating or dilution
Each run.
M
Sample Extraction
Calibration valve
material
Inert to sample constituents
(e.g., PFA Teflon or PFA Teflon coated)
Each test.
S
Sample Extraction
Sample pump material
Inert to sample
constituents
Each test.
M
Sample Extraction
Manifold material
Inert to sample
constituents
Each test.
M
Particulate Removal
Filter inertness
Pass calibration error
check
Each calibration error
check.
M
System Calibration
Performance
System calibration error (CE)
test
CE ≤5.0 % of the calibration
span for the low-, mid-or high-level Hg 0 calibration
gas
Alternative specification: ≤0.5 µg/m 3 absolute
difference between system response and reference value
Before initial run and after a
failed system integrity check or drift test.
M
System Calibration
Performance
System integrity check
Error ≤5.0% of the calibration
span for the zero and mid- or high-level HgCl2 calibration gas
Alternative specification: ≤0.5 µg/m 3 absolute
difference between system response and reference value
Before initial run, after each
run, at the beginning of subsequent test days, and after a failed
system integrity check or drift test.
M
System Performance
System response time
Used to determine minimum
sampling time per point
During initial 3-point system
calibration error test.
M
System Performance
Drift
≤3.0% of calibration span for
the zero and mid- or high-level gas
Alternative specification: ≤0.3 µg/m 3 absolute
difference between pre- and post-run system calibration error
percentages.
At least once per test
day.
M
System Performance
Minimum sampling time
The greater of two times the
system response time or 10 minutes. Concentrating systems must also
include at least 4 cycles
Each sampling point.
M
System Performance
Percentage spike recovery and
relative standard deviation
Percentage spike recovery, at
the target level: 100 ±10%
Relative standard deviation: ≤5 percent
Alternative specification: absolute difference between calculated
and measured spike values ≤0.5 µg/m 3
Before initial run; dynamic
spiking not required until 1/1/09.
M
Sample Point Selection
Number and Location of Sample
Points
For emission testing
applications, use 12 points, located according to Method 1 in
appendix A-1 to this part, unless the results of a stratification
test allow fewer points to be used
Prior to first run.
For Part 60 RATAs, follow the
procedures in Performance Specification 2, section 8.1.3, and for
Part 75 RATAs, follow the procedures in section 6.5.6 of appendix A
to Part 75. That is:
• At any test location, you
may use 3 sample points located at 16.7, 50.0, and 83.3% of a
“long” measurement line passing through the centroidal area;
or
• At any test location, you
may use 6 sample points along a diameter, located according to
Method 1 (Part 75 RATAs, only); or
• At a location where
stratification is not expected and the measurement line is >2.4
m (7.8 ft), you may use 3 sample points located along a “short”
measurement line at 0.4, 1.0, and 2.0 m from the stack or duct wall
or, for Part 75 only, sample points may be located at 4.4, 14.6,
and 29.6% of the measurement line; or
• After a wet scrubber or at a
point where dissimilar gas streams are combined, either locate 3
sample points along the “long” measurement line or locate 6 Method
1 points along a diameter (Part 75, only), unless the results of a
stratification test allow you to use a “short” 3-point measurement
line or to sample at a single point
• If it can be demonstrated
that stack gas concentration is ≤3 µg/m 3, then the test
site is exempted from stratification testing. Use the 3-point
“short” measurement line if the stack diameter is >2.4 m (7.8
ft) and the 3-point “long” line for stack diameters ≤2.4 m (7.8
ft)
A
Sample Point Selection
Stratification Test (See
section 8.1.3).
If the Hg concentration
2 at each traverse point during the stratification test
is:
• Within ±5% of mean, use 1-point sampling (at the point closest to
the mean); or
• Not within ±5% of mean, but is within ±10% of mean, use 3-point
sampling. Locate points according to section 8.1.3.2.2 of this
method.
Alternatively, if the Hg concentration at each point is:
• Within ±0.2 µg/m 3 of mean, use 1-point sampling (at
the point closest to the mean); or
• Not within ±0.2 µg/m 3 of mean, but is within ±0.5
µg/m 3 of mean, use 3-point sampling. Locate points
according to section 8.1.3.2.2 of this method.
Prior to first run.
Prior to 1/1/09, you may (1) forgo stratification testing and use 3
sampling points (as per section 8.1.3.2.2) or (2) perform a SO2
stratification test (see sections 6.5.6.1 and 6.5.6.3 of appendix A
to part 75), in lieu of a Hg stratification test. If the test
location is unstratified or minimally stratified for SO2, it can be
considered unstratified or minimally stratified for Hg also.
M
Data Recording
Frequency
Once per cycle
During run.
S
Data Parameters
Sample concentration and
calibration span
All analyzer readings during
each run within calibration span
Each run.
M
Data Parameters
Sample concentration and
calibration span
All analyzer readings during
dynamic spiking tests within 120% of calibration span
Each spike injection.
M
Data Parameters
Sample concentration and
calibration span
Average Hg concentration for
the run ≤calibration span
Each run.
1 M = Mandatory; S = Suggested; A
= Alternative.
2 These may either be the
unadjusted Hg concentrations or concentrations normalized to
account for temporal variations.
10.0 Calibration and Standardization What measurement system
calibrations are required?
Your analyzer must be calibrated with Hg° standards. The initial
3-point system calibration error test described in section 8.2.4 is
required before you start the test. Also, prior to and following
test runs, the two-point system integrity checks described in
sections 8.2.5 and 8.2.8 are required. On and after January 1,
2009, the pre-test dynamic spiking procedure described in section
8.2.7 is also required to verify that the accuracy of the
measurement system is suitable and not adversely affected by the
flue gas matrix.
11.0 Analytical Procedures
Because sample collection and analysis are performed together
(see section 8), additional discussion of the analytical procedure
is not necessary.
12.0 Calculations and Data Analysis
You must follow the procedures for calculations and data
analysis listed in this section.
12.1 Nomenclature. The terms used in the equations are defined
as follows:
Bws = Moisture content of sample gas as measured by Method 4 in
Appendix A-3 to this part, percent/100. Cavg = Average unadjusted
Hg concentration for the test run, as indicated by the data
recorder µg/m 3. C baseline = Average Hg concentration measured
before and after dynamic spiking injections, µg/m 3. Cd = Hg
concentration, dry basis, µg/m 3. Cdif = Absolute value of the
difference between the measured Hg concentrations of the reference
HgCl2 calibration gas, with and without the individual or combined
interference gases, µg/m 3. Cdif avg = Average of the 3 absolute
values of the difference between the measured Hg concentrations of
the reference HgCl2 calibration gas, with and without the
individual or combined interference gases, µg/m 3. Cgas = Average
Hg concentration in the effluent gas for the test run, adjusted for
system calibration error, µg/m 3. Cint = Measured Hg concentration
of the reference HgCl2 calibration gas plus the individual or
combined interference gases, µg/m 3. Cm = Average of pre- and
post-run system integrity check responses for the upscale (i.e.,
mid- or high-level) calibration gas, µg/m 3. Cma = Actual
concentration of the upscale (i.e., mid- or high-level) calibration
gas used for the system integrity checks, µg/m 3. C0 = Average of
pre- and post-run system integrity check responses from the zero
gas, µg/m 3. Cnative = Vapor phase Hg concentration in the source
effluent, µg/m 3. Cref = Measured Hg concentration of the reference
HgCl2 calibration gas alone, in the interference test, µg/m 3. Cs =
Measured concentration of a calibration gas (zero-, low-, mid-, or
high-level), when introduced in system calibration mode, µg/m 3.
Cspike = Actual Hg concentration of the spike gas, µg/m 3. C*spike
= Hg concentration of the spike gas required to achieve a certain
target value for the spiked sample Hg concentration, µg/m 3. Css =
Measured Hg concentration of the spiked sample at the target level,
µg/m 3. C*ss = Expected Hg concentration of the spiked sample at
the target level, µg/m 3. Ctarget = Target Hg concentration of the
spiked sample, µg/m 3. CTnative = Measured tracer gas concentration
present in native effluent gas, ppm. CTdir = Tracer gas
concentration injected with spike gas, ppm. CTv = Diluted tracer
gas concentration measured in a spiked sample, ppm. Cv = Certified
Hg° or HgCl2 concentration of a calibration gas (zero, low, mid, or
high), µg/m 3. Cw = Hg concentration measured under moist sample
conditions, wet basis, µg/m 3. CS = Calibration span, µg/m 3. D =
Zero or upscale drift, percent of calibration span. DF = Dilution
factor of the spike gas, dimensionless. I = Interference response,
percent of calibration span. Qprobe = Total flow rate of the stack
gas sample plus the spike gas, liters/min. Qspike = Flow rate of
the spike gas, liters/min. Ri = Individual injection spike
recovery, %. R = Mean value of spike recoveries at a particular
target level, %. RSD = Relative standard deviation, %;. SCE =
System calibration error, percent of calibration span. SCEi =
Pre-run system calibration error during the two-point system
integrity check, percent of calibration span. SCEf = Post-run
system calibration error during the two-point system integrity
check, percent of calibration span.
12.2 System Calibration Error. Use Equation 30A-1 to calculate
the system calibration error. Equation 30A-1 applies to: 3-point
system calibration error tests performed with Hg° standards; and
pre- and post-run two-point system integrity checks performed with
HgCl2.
12.3 Drift Assessment. Use Equation 30A-2 to separately
calculate the zero and upscale drift for each test run.
12.3 Effluent Hg Concentration. For each test run, calculate
Cavg, the arithmetic average of all valid Hg concentration values
recorded during the run. Then, adjust the value of Cavg for system
calibration error, using Equation 30A-3.
12.4 Moisture Correction. Use Equation 30A-4a if your
measurements need to be corrected to a dry basis.
Use Equation 30A-4b if your measurements need to be corrected to
a wet basis.
12.5 Dynamic Spike Gas Concentrations. Use Equation 30A-5 to
determine the spike gas concentration needed to produce a spiked
sample with a certain “target” Hg concentration.
12.6 Spiked Sample Concentration. Use Equation 30A-6 to
determine the expected or theoretical Hg concentration of a spiked
sample.
12.7 Spike Recovery. Use Equation 30A-7 to calculate the
percentage recovery of each spike.
12.8 Relative Standard Deviation. Use Equation 30A-8 to
calculate the relative standard deviation of the individual
percentage spike recovery values from the mean.
12.9 Spike Dilution Factor. Use Equation 30A-9 to calculate the
spike dilution factor, using either direct flow measurements or
tracer gas measurements.
12.10 Native Concentration. For spiking procedures that inject
blank or carrier gases (at the spiking flow rate, Qspike) between
spikes, use Equation 30A-10 to calculate the native
concentration.
For spiking procedures that halt all injections between spikes,
the native concentration equals the average baseline concentration
(see Equation 30A-11).
12.11 Overall Interference Response. Use equation 30A-12 to
calculate the overall interference response.
Where, for each interference gas (or mixture):
13.0 Method Performance
13.1 System Calibration Error Test. This specification applies
to the 3-point system calibration error tests using Hg 0. At each
calibration gas level tested (low-, mid-, or high-level), the
calibration error must be within ±5.0 percent of the calibration
span. Alternatively, the results are acceptable if | Cs − Cv | ≤0.5
µg/m 3.
13.2 System Integrity Checks. This specification applies to all
pre- and post-run 2-point system integrity checks using HgCl2 and
zero gas. At each calibration gas level tested (zero and mid- or
high-level), the error must be within ±5.0 percent of the
calibration span. Alternatively, the results are acceptable if | Cs
− Cv | ≤0.5 µg/m 3.
13.3 Drift. For each run, the low-level and upscale drift must
be less than or equal to 3.0 percent of the calibration span. The
drift is also acceptable if the pre- and post-run system integrity
check responses do not differ by more than 0.3 µg/m 3 (i.e., | Cs
post-run − Cs pre-run | ≤0.3 µg/m 3).
13.4 Interference Test. Summarize the results following the
format contained in Table 30A-4. For each interference gas (or
mixture), calculate the mean difference between the measurement
system responses with and without the interference test gas(es).
The overall interference response for the analyzer that was used
for the test (calculated according to Equation 30A-12), must not be
greater than 3.0 percent of the calibration span used for the test
(see section 8.6). The results of the interference test are also
acceptable if the sum of the absolute average differences for all
interference gases (i.e., Σ Cdif avg) does not exceed 0.3 µg/m
3.
13.5 Dynamic Spiking Test. For the pre-test dynamic spiking, the
mean value of the percentage spike recovery must be 100 ±10
percent. In addition, the relative standard deviation (RSD) of the
individual percentage spike recovery values from the mean must be
≤5.0 percent. Alternatively, if the mean percentage recovery is not
met, the results are acceptable if the absolute difference between
the theoretical spiked sample concentration (see section 12.6) and
the actual average value of the spiked sample concentration is ≤0.5
µg/m 3.
1. EPA Traceability Protocol for Qualification and Certification
of Elemental Mercury Gas Generators, expected publication date
December 2008, see www.epa.gov/ttn/emc.
2. EPA Traceability Protocol for Qualification and Certification
of Oxidized Mercury Gas Generators, expected publication date
December 2008, see www.epa.gov/ttn/emc.
3. EPA Traceability Protocol for Assay and Certification of
Gaseous Calibration Standards, expected revision publication date
December 2008, see www.epa.gov/ttn/emc.
17.0 Figures and Tables
Table 30A-3 - Interference Check Gas
Concentrations
Potential interferent gas
1
Concentration,
tentative - (balance N2)
CO2
15% ±1% CO2
CO
100 ±20 ppm
HCl
2
100 ±20 ppm
NO
2
250 ±50 ppm
SO2
200 ±20 ppm
O2
3% ±1% O2
H2O
10% ±1% H2O
Nitrogen
Balance
Other
1 Any of these specific gases can
be tested at a lower level if the manufacturer has provided
reliable means for limiting or scrubbing that gas to a specified
level.
2 HCl and NO must be tested as a
mixture.
Method 30B - Determination
of Total Vapor Phase Mercury Emissions From Coal-Fired Combustion
Sources Using Carbon Sorbent Traps 1.0 Scope and Application What
is Method 30B?
Method 30B is a procedure for measuring total vapor phase
mercury (Hg) emissions from coal-fired combustion sources using
sorbent trap sampling and an extractive or thermal analytical
technique. This method is only intended for use only under
relatively low particulate conditions (e.g., sampling after all
pollution control devices). Quality assurance and quality control
requirements are included to assure that you, the tester, collect
data of known and acceptable quality for each testing program. This
method does not completely describe all equipment, supplies, and
sampling and analytical procedures you will need, but instead
refers to other test methods for some of the details. Therefore, to
obtain reliable results, you should also have a thorough knowledge
of these additional methods which are found in Appendices A-1 and
A-3 to this part:
(a) Method 1 - Sample and Velocity Traverses for Stationary
Sources.
(b) Method 4 - Determination of Moisture Content in Stack
Gases.
(c) Method 5 - Determination of Particulate Matter Emissions
from Stationary Sources
1.1 Analytes. What does this method determine? This method is
designed to measure the mass concentration of total vapor phase Hg
in flue gas, including elemental Hg (Hg 0) and oxidized forms of Hg
(Hg+2), in micrograms per dry standard cubic meter (µg/dscm).
Analyte
CAS No.
Analytical range and
sensitivity
Elemental Hg (Hg
0 )
7439-97-6
Typically 0.1 µg/dscm to
>50 µg/dscm.
Oxidized Hg
(Hg+2)
(Same)
1.2 Applicability. When is this method required? Method 30B is a
reference method for relative accuracy test audits (RATAs) of vapor
phase Hg CEMS and sorbent trap monitoring systems installed at
coal-fired boilers and is also appropriate for Hg emissions testing
at such boilers. It is intended for use only under relatively low
particulate conditions (i.e., sampling after all pollution control
devices); in cases where significant amounts of particle-bound Hg
may be present, an isokinetic sampling method for Hg should be
used. Method 30B may also be specified by New Source Performance
Standards (NSPS), National Emission Standards for Hazardous Air
Pollutants (NESHAP), emissions trading programs, State
Implementation Plans (SIPs), and operating permits that require
measurement of Hg concentrations in stationary source emissions,
either to determine compliance with an applicable emission standard
or limit, or to conduct RATAs of Hg CEMS and sorbent trap
monitoring systems.
1.3 Data Quality Objectives (DQO). How good must my collected
data be? Method 30B has been designed to provide data of high and
known quality for Hg emissions testing and for RATA testing of Hg
monitoring systems, including CEMS and sorbent trap monitors. In
these and other applications, the principal objective is to ensure
the accuracy of the data at the actual emissions levels and in the
actual emissions matrix encountered. To meet this objective,
NIST-traceable calibration standards must be used and method
performance tests are required.
2.0 Summary of Method
Known volumes of flue gas are extracted from a stack or duct
through paired, in-stack sorbent media traps at an appropriate flow
rate. Collection of mercury on the sorbent media in the stack
mitigates potential loss of mercury during transport through a
probe/sample line. For each test run, paired train sampling is
required to determine measurement precision and verify
acceptability of the measured emissions data. A field recovery test
which assesses recovery of an elemental Hg spike to determine
measurement bias is also used to verify data acceptability. The
sorbent traps are recovered from the sampling system, prepared for
analysis as needed, and analyzed by any suitable determinative
technique that can meet the performance criteria.
3.0 Definitions
3.1 Analytical System is the combined equipment and
apparatus used to perform sample analyses. This includes any
associated sample preparation apparatus e.g., digestion equipment,
spiking systems, reduction devices, etc., as well as analytical
instrumentation such as UV AA and UV AF cold vapor analyzers.
3.2 Calibration Standards are the Hg containing solutions
prepared from NIST traceable standards and are used to directly
calibrate analytical systems.
3.3 Independent Calibration Standard is a NIST traceable
standard obtained from a source or supplier independent of that for
the calibration standards and is used to confirm the integrity of
the calibration standards used.
3.4 Method Detection Limit (MDL) is the lowest mass of Hg
greater than zero that can be estimated and reported by your
candidate analytical technique. The MDL is statistically derived
from replicate low level measurements near your analytical
instrument's detection level.
3.5 NIST means the National Institute of Standards and
Technology, located in Gaithersburg, Maryland.
3.6 Run means a series of gas samples taken successively
from the stack or duct. A test normally consists of a specific
number of runs.
3.7 Sorbent Trap means a cartridge or sleeve containing a
sorbent media (typically activated carbon treated with iodine or
some other halogen) with multiple sections separated by an inert
material such as glass wool. These sorbent traps are optimized for
the quantitative capture of elemental and oxidized forms of Hg and
can be analyzed by multiple techniques.
3.8 Test refers to the series of runs required by the
applicable regulation.
3.9 Thermal Analysis means an analytical technique where
the contents of the sorbent traps are analyzed using a thermal
technique (desorption or combustion) to release the captured Hg in
a detectable form for quantification.
3.10 Wet Analysis means an analytical technique where the
contents of the sorbent tube are first leached or digested to
quantitatively transfer the captured Hg to liquid solution for
subsequent analysis.
4.0 Interferences
Interferences may result from the sorbent trap material used as
well as from the measurement environment itself. The iodine present
on some sorbent traps may impart a negative measurement bias. High
levels of sulfur trioxide (SO3) are also suspected to compromise
the performance of sorbent trap Hg capture. These, and other,
potential interferences are assessed by performing the analytical
matrix interference, Hg 0 and HgCl2 analytical bias and field
recovery tests.
5.0 Safety
What safety measures should I consider when using this method?
This method may require you to work with hazardous materials and in
hazardous conditions. You are encouraged to establish safety
procedures before using the method. Among other precautions, you
should become familiar with the safety recommendations in the gas
analyzer user's manual. Occupational Safety and Health
Administration (OSHA) regulations concerning use of compressed gas
cylinders and noxious gases may apply.
5.1 Site Hazards. Prior to applying these
procedures/specifications in the field, the potential hazards at
the test site should be considered; advance coordination with the
site is critical to understand the conditions and applicable safety
policies. At a minimum, portions of the sampling system will be
hot, requiring appropriate gloves, long sleeves, and caution in
handling this equipment.
5.2 Laboratory Safety. Policies should be in place to minimize
risk of chemical exposure and to properly handle waste disposal in
the laboratory. Personnel shall wear appropriate laboratory attire
according to a Chemical Hygiene Plan established by the
laboratory.
5.3 Reagent Toxicity/Carcinogenicity. The toxicity and
carcinogenicity of any reagents used must be considered. Depending
upon the sampling and analytical technologies selected, this
measurement may involve hazardous materials, operations, and
equipment and this method does not address all of the safety
problems associated with implementing this approach. It is the
responsibility of the user to establish appropriate safety and
health practices and determine the applicable regulatory
limitations prior to performance. Any chemical should be regarded
as a potential health hazard and exposure to these compounds should
be minimized. Chemists should refer to the Material Safety Data
Sheet (MSDS) for each chemical used.
5.4 Waste Disposal. Any waste generated by this procedure must
be disposed of according to a hazardous materials management plan
that details and tracks various waste streams and disposal
procedures.
6.0 Equipment and Supplies
The following list is presented as an example of key equipment
and supplies likely required to measure vapor-phase Hg using a
sorbent trap sampling system. It is recognized that additional
equipment and supplies may be needed. Collection of paired samples
is required.
6.1 Sorbent Trap Sampling System. A typical sorbent trap
sampling system is shown in Figure 30B-1 in section 17.0. The
sorbent trap sampling system shall include the following
components:
6.1.1 Sorbent Traps. The sorbent media used to collect Hg must
be configured in a trap with at least two distinct segments or
sections, connected in series, that are amenable to separate
analyses. section 1 is designated for primary capture of gaseous
Hg. section 2 is designated as a backup section for determination
of vapor phase Hg breakthrough. Each sorbent trap must be inscribed
or otherwise permanently marked with a unique identification
number, for tracking purposes. The sorbent media may be any
collection material (e.g., carbon, chemically-treated filter, etc.)
capable of quantitatively capturing and recovering for subsequent
analysis, all gaseous forms of Hg in the emissions from the
intended application. Selection of the sorbent media shall be based
on the material's ability to achieve the performance criteria
contained in this method as well as the sorbent's vapor phase Hg
capture efficiency for the emissions matrix and the expected
sampling duration at the test site. The sorbent media must be
obtained from a source that can demonstrate their quality assurance
and quality control (see section 7.2). The paired sorbent traps are
supported on a probe (or probes) and inserted directly into the
flue gas stream.
6.1.2 Sampling Probe Assembly. Each probe assembly shall have a
leak-free attachment to the sorbent trap(s). Each sorbent trap must
be mounted at the entrance of or within the probe such that the gas
sampled enters the trap directly. Each probe/sorbent trap assembly
must be heated to a temperature sufficient to prevent liquid
condensation in the sorbent trap(s). Auxiliary heating is required
only where the stack temperature is too low to prevent
condensation. Use a calibrated thermocouple to monitor the stack
temperature. A single probe capable of operating the paired sorbent
traps may be used. Alternatively, individual probe/sorbent trap
assemblies may be used, provided that the individual sorbent traps
are co-located to ensure representative Hg monitoring.
6.1.3 Moisture Removal Device. A moisture removal device or
system shall be used to remove water vapor from the gas stream
prior to entering dry gas flow metering devices.
6.1.4 Vacuum Pump. Use a leak-tight, vacuum pump capable of
operating within the system's flow range.
6.1.5 Gas Flow Meter. A gas flow meter (such as a dry gas meter,
thermal mass flow meter, or other suitable measurement device)
shall be used to determine the total sample volume on a dry basis,
in units of standard cubic meters. The meter must be sufficiently
accurate to measure the total sample volume to within 2 percent and
must be calibrated at selected flow rates across the range of
sample flow rates at which the sampling train will be operated. The
gas flow meter shall be equipped with any necessary auxiliary
measurement devices (e.g., temperature sensors, pressure
measurement devices) needed to correct the sample volume to
standard conditions.
6.1.6 Sample Flow Rate Meter and Controller. Use a flow rate
indicator and controller for maintaining necessary sampling flow
rates.
6.1.7 Temperature Sensor. Same as section 6.1.1.7 of Method 5 in
Appendix A-3 to this part.
6.1.8 Barometer. Same as section 6.1.2 of Method 5 in Appendix
A-3 to this part.
6.1.9 Data Logger (optional). Device for recording associated
and necessary ancillary information (e.g., temperatures, pressures,
flow, time, etc.).
6.2 Gaseous Hg 0 Sorbent Trap Spiking System. A known mass of
gaseous Hg 0 must be either present on or spiked onto the first
section of sorbent traps in order to perform the Hg 0 and HgCl2
analytical bias test and the field recovery study. Any approach
capable of quantitatively delivering known masses of Hg 0 onto
sorbent traps is acceptable. Several spiking technologies or
devices are available to meet this objective. Their practicality is
a function of Hg mass spike levels. For low levels, NIST-certified
or NIST-traceable gas generators or tanks may be suitable. An
alternative system, capable of delivering almost any mass required,
makes use of NIST-certified or NIST-traceable Hg salt solutions
(e.g., HgCl2, Hg(NO3)2). With this system, an aliquot of known
volume and concentration is added to a reaction vessel containing a
reducing agent (e.g., stannous chloride); the Hg salt solution is
reduced to Hg 0 and purged onto the sorbent trap using an impinger
sparging system. When available, information on example spiking
systems will be posted at http://www.epa.gov/ttn/emc.
6.3 Sample Analysis Equipment. Any analytical system capable of
quantitatively recovering and quantifying total Hg from the sorbent
media selected is acceptable provided that the analysis can meet
the performance criteria described in this method. Example recovery
techniques include acid leaching, digestion, and thermal
desorption/direct combustion. Example analytical techniques
include, but are not limited to, ultraviolet atomic fluorescence
(UV AF), ultraviolet atomic absorption (UV AA) with and without
gold trapping, and X-ray fluorescence (XRF) analysis.
6.3 Moisture Measurement System. If correction of the measured
Hg emissions for moisture is required (see section 8.3.3.7), either
Method 4 in Appendix A-3 to this part or other moisture measurement
methods approved by the Administrator will be needed to measure
stack gas moisture content.
7.0 Reagents and Standards
7.1 Reagents and Standards. Only NIST-certified or
NIST-traceable calibration standards, standard reference materials,
and reagents shall be used for the tests and procedures required by
this method.
7.2 Sorbent Trap Media. The sorbent trap media shall be prepared
such that the material used for testing is of known and acceptable
quality. Sorbent supplier quality assurance/quality control
measures to ensure appropriate and consistent performance such as
sorptive capacity, uniformity of preparation treatments, and
background levels shall be considered.
8.0 Sample Collection and Handling
This section presents the sample collection and handling
procedures along with the pretest and on-site performance tests
required by this method. Since you may choose different options to
comply with certain performance criteria, each test report must
identify the specific options selected and document the results
with respect to the performance criteria of this method.
8.1 Selection of Sampling Sites and Sampling Points. What
sampling site and sampling points do I select? Same as section 8.1
of Method 30A of this appendix.
8.2 Measurement System Performance Tests. What performance
criteria must my measurement system meet? The following laboratory
and field procedures and associated criteria of this section are
designed to ensure (1) selection of a sorbent and analytical
technique combination capable of quantitative collection and
analysis of gaseous Hg, (2) collection of an adequate amount of Hg
on each sorbent trap during field tests, and (3) adequate
performance of the method for each test program: The primary
objectives of these performance tests are to characterize and
verify the performance of your intended analytical system and
associated sampling and analytical procedures, and to define the
minimum amount of Hg (as the sample collection target) that can be
quantified reliably.
(a) Analytical Matrix Interference Test;
(b) Determination of Minimum Sample Mass;
(c) Hg 0 and HgCl2 Analytical Bias Test;
(d) Determination of Nominal Sample Volume;
(e) Field Recovery Test.
8.2.1 Analytical Matrix Interference Test and Minimum Sample
Dilution.
(a) The analytical matrix interference test is a laboratory
procedure. It is required only if you elect to use a liquid
digestion analytical approach and needs to be performed only once
for each sorbent material used. The purpose of the test is to
verify the presence or absence of known and potential analytical
matrix interferences, including the potential negative bias
associated with iodine common to many sorbent trap materials. The
analytical matrix interference test determines the minimum dilution
(if any) necessary to mitigate matrix effects on the sample
digestate solutions.
(b) The result of the analytical matrix interference test, i.e.,
the minimum sample dilution required (if any) for all sample
analyses, is used to establish the minimum sample mass needed for
the Hg 0 and HgCl2 analytical bias test and to determine the
nominal sample volume for a test run. The analytical matrix
interference test is sorbent material-specific and shall be
performed for each sorbent material you intend to use for field
sampling and analysis. The test shall be performed using a mass of
sorbent material comparable to the sorbent mass typically used in
the first section of the trap for sampling. Similar sorbent
materials from different sources of supply are considered to be
different materials and must be tested individually. You must
conduct the analytical matrix interference test for each sorbent
material prior to the analysis of field samples.
8.2.1.1 Analytical Matrix Interference Test Procedures. Digest
and prepare for analysis a representative mass of sorbent material
(unsampled) according to your intended laboratory techniques for
field samples. Analyze the digestate according to your intended
analytical conditions at the least diluted level you intend to use
for sample analysis (e.g., undiluted, 1 in 10 dilution, etc.).
Determine the Hg concentration of the undiluted digestate solution.
Prepare a series of solutions with a fixed final volume containing
graduated aliquots of the sample digestate and, a fixed aliquot of
a calibration standard (with the balance being Hg-free reagent or
H20) to establish solutions of varied digestate dilution ratio
(e.g., 1:2, 1:5, 1:10, 1:100, etc. - see example in section
8.2.1.3, below). One of these solutions should contain only the
aliquot of the calibration standard in Hg-free reagent or H2O. This
will result in a series of solutions where the amount of Hg is held
relatively constant and only the volume of digestate diluted is
varied. Analyze each of these solutions following intended sample
analytical procedures and conditions, determining the concentration
for each solution.
8.2.1.2 Analytical Matrix Interference Test Acceptance Criteria.
Compare the measured concentration of each solution containing
digestate to the measured concentration of the digestate-free
solution. The lowest dilution ratio of any solution having a Hg
concentration within ±5 percent of the digestate-free solution is
the minimum dilution ratio required for analysis of all samples. If
you desire to measure the digestate without dilution, the ±5
percent criterion must be met at a dilution ratio of at least 9:10
(i.e., ≥90% digestate).
8.2.1.3 Example Analytical Matrix Interference Test. An example
analytical matrix interference test is presented below. Additional
information on the conduct of the analytical matrix interference
test will be posted at http://www.epa.gov/ttn/emc. Determine
the most sensitive working range for the analyzer to be used. This
will be a narrow range of concentrations. Digest and prepare for
analysis a representative mass of sorbent material (unsampled)
according to your intended laboratory techniques for sample
preparation and analysis. Prepare a calibration curve for the most
sensitive analytical region, e.g., 0.0, 0.5, 1.0, 3.0, 5.0, 10 ppb.
Using the highest calibration standard, e.g., 10.0 ppb, prepare a
series of solutions by adding successively smaller increments of
the digestate to a fixed volume of the calibration standard and
bringing each solution to a final fixed volume with mercury-free
deionized water (diH2O). To 2.0 ml of the calibration standard add
18.0, 10.0, 4.0, 2.0, 1.0, 0.2, and 0.0 ml of the digestate. Bring
the final volume of each solution to a total volume of 20 ml by
adding 0.0, 8.0, 14.0, 16.0, 17.0, 17.8, and 18.0 ml of diH2O. This
will yield solutions with dilution ratios of 9:10, 1:2, 1:5, 1:10,
1:20, 1:100, and 0:10, respectively. Determine the Hg concentration
of each solution. The dilution ratio of any solution having a
concentration that is within ±5 percent of the concentration of the
solution containing 0.0 ml of digestate is an acceptable dilution
ratio for analyzing field samples. If more than one solution meets
this criterion, the one with the lowest dilution ratio is the
minimum dilution required for analysis of field samples. If the
9:10 dilution meets this criterion, then no sample dilution is
required.
8.2.2 Determination of Minimum Sample Mass. The minimum mass of
Hg that must be collected per sample must be determined. This
information is necessary in order to effectively perform the Hg 0
and HgCl2 Analytical Bias Test, to estimate target sample
volumes/sample times for test runs, and to ensure the quality of
the measurements. The determination of minimum sample mass is a
direct function of analytical technique, measurement sensitivity,
dilutions, etc. This determination is required for all analytical
techniques. Based on the analytical approach you employ, you should
determine the most sensitive calibration range. Based on a
calibration point within that range, you must consider all sample
treatments (e.g., dilutions) to determine the mass of sample that
needs to be collected to ensure that all sample analyses fall
within your calibration curve.
8.2.2.1 Determination of Minimum Calibration Concentration or
Mass. Based on your instrument's sensitivity and linearity,
determine the calibration concentrations or masses that make up a
representative low level calibration range. Verify that you are
able to meet the multipoint calibration performance criteria in
section 11.0 of this method. Select a calibration concentration or
mass that is no less than 2 times the lowest concentration or mass
in your calibration curve. The lowest point in your calibration
curve must be at least 5, and preferably 10, times the Method
Detection Limit (MDL), which is the minimum amount of the analyte
that can be detected and reported. The MDL must be determined at
least once for the analytical system using an MDL study such as
that found in section 15.0 to Method 301 of appendix A to part 63
of this chapter.
Note to section 8.2.2.1:
While it might be desirable to base the minimum calibration
concentration or mass on the lowest point in the calibration curve,
selecting a higher concentration or mass is necessary to ensure
that all analyses of the field samples will fall within the
calibration curve. Therefore, it is strongly recommended that you
select a minimum calibration concentration or mass that is
sufficiently above the lowest point of the calibration curve (see
examples in sections 8.2.2.2.1 and 8.2.2.2.2 below).
8.2.2.2 Determination of Minimum Sample Mass. Based on your
minimum calibration concentration or mass and other sample
treatments including, but not limited to, final digestate volume
and minimum sample dilution, determine the minimum sample mass.
Consideration should also be given to the Hg levels expected to be
measured in section 2 of the sorbent traps and to the breakthrough
criteria presented in Table 9-1.
8.2.2.2.1 Example Determination of Minimum Sample Mass for
Thermal Desorption Analysis. A thermal analysis system has been
calibrated at five Hg mass levels: 10 ng, 20 ng, 50 ng, 100 ng, 200
ng, and shown to meet the calibration performance criteria in this
method. Based on 2 times the lowest point in the calibration curve,
20 ng is selected as the minimum calibration mass. Because the
entire sample is analyzed and there are no dilutions involved, the
minimum sample mass is also 20 ng.
Note:
In this example, if the typical background (blank) Hg levels in
section 2 were relatively high (e.g., 3 to 5 ng), a sample mass of
20 ng might not have been sufficient to ensure that the
breakthrough criteria in Table 9-1 would be met, thereby
necessitating the use of a higher point on the calibration curve
(e.g., 50 ng) as the minimum calibration and sample mass.
8.2.2.2.2 Example Determination of Minimum Sample Mass for Acid
Leachate/Digestate Analysis. A cold vapor analysis system has been
calibrated at four Hg concentration levels: 2 ng/L, 5 ng, 10 ng/L,
20 ng/L, and shown to meet the calibration performance criteria in
this method. Based on 2 times the lowest point in the calibration
curve, 4 ng/L was selected as the minimum calibration
concentration. The final sample volume of a digestate is nominally
50 ml (0.05 L) and the minimum dilution necessary was determined to
be 1:100 by the Analytical Matrix Interference Test of section
8.2.1. The following calculation would be used to determine the
minimum sample mass.
Minimum sample mass = (4 ng/L) × (0.05 L) × (100) = 20 ng Note:
In this example, if the typical background (blank) Hg levels in
section 2 were relatively high (e.g., 3 to 5 ng), a sample mass of
20 ng might not have been sufficient to ensure that the
breakthrough criterion in Table 9-1 would be met, thereby
necessitating the use of a higher point on the calibration curve
(e.g., 10 ng/L) as the minimum calibration concentration.
8.2.3 Hg 0 and HgCl2 Analytical Bias Test. Before analyzing any
field samples, the laboratory must demonstrate the ability to
recover and accurately quantify Hg 0 and HgCl2 from the chosen
sorbent media by performing the following analytical bias test for
sorbent traps spiked with Hg 0 and HgCl2. The analytical bias test
is performed at a minimum of two distinct sorbent trap Hg loadings
that will: (1) Represent the lower and upper bound of sample Hg
loadings for application of the analytical technique to the field
samples, and (2) be used for data validation.
8.2.3.1 Hg 0 and HgCl2 Analytical Bias Test Procedures.
Determine the lower and upper bound mass loadings. The minimum
sample mass established in section 8.2.2.2 can be used for the
lower bound Hg mass loading although lower Hg loading levels are
acceptable. The upper bound Hg loading level should be an estimate
of the greatest mass loading that may result as a function of stack
concentration and volume sampled. As previously noted, this test
defines the bounds that actual field samples must be within in
order to be valid.
8.2.3.1.1 Hg 0 Analytical Bias Test. Analyze the front section
of three sorbent traps containing Hg 0 at the lower bound mass
loading level and the front section of three sorbent traps
containing Hg 0 at the upper bound mass loading level. In other
words, analyze each mass loading level in triplicate. You may refer
to section 6.2 for spiking guidance. Prepare and analyze each
spiked trap, using the same techniques that will be used to prepare
and analyze the field samples. The average recovery for the three
traps at each mass loading level must be between 90 and 110
percent. If multiple types of sorbent media are to be analyzed, a
separate analytical bias test is required for each sorbent
material.
8.2.3.1.2 HgCl2 Analytical Bias Test. Analyze the front section
of three sorbent traps containing HgCl2 at the lower bound mass
loading level and the front section of three traps containing HgCl2
at the upper bound mass loading level. HgCl2 can be spiked as a
gas, or as a liquid solution containing HgCl2. However the liquid
volume spiked must be <100 µL. Prepare and analyze each spiked
trap, using the techniques that will be used to prepare and analyze
the field samples. The average recovery for three traps at each
spike concentration must be between 90 and 110 percent. Again, if
multiple types of sorbent media are to be analyzed, a separate
analytical bias test is required for each sorbent material.
8.2.4 Determination of Target Sample Volume. The target sample
volume is an estimate of the sample volume needed to ensure that
valid emissions data are collected (i.e., that sample mass Hg
loadings fall within the analytical calibration curve and are
within the upper and lower bounds set by the analytical bias
tests). The target sample volume and minimum sample mass can also
be determined by performing a diagnostic test run prior to
initiation of formal testing.
Example:If the minimum sample mass is 50 ng and the concentration
of mercury in the stack gas is estimated to be 2 µg/m 3 (ng/L) then
the following calculation would be used to determine the target
sample volume: Target Sample Volume = (50 ng) / (2 ng/L) = 25 L
Note to section 8.2.4:
For the purposes of relative accuracy testing of Hg monitoring
systems under subpart UUUUU of part 63 of this chapter and
Performance Specifications 12A and 12B in appendix B to this part,
when the stack gas Hg concentration is expected to be very low
(<0.5 µg/dscm), you may estimate the Hg concentration at 0.5
µg/dscm.
8.2.5 Determination of Sample Run Time. Sample run time will be
a function of minimum sample mass (see section 8.2.2), target
sample volume and nominal equipment sample flow rate. The minimum
sample run time for conducting relative accuracy test audits of Hg
monitoring systems is 30 minutes and for emissions testing to
characterize an emission source is 1 hour. The target sample run
time can be calculated using the following example.
Example:If the target sample volume has been determined to be 25 L,
then the following formula would be used to determine the sampling
time necessary to acquire 25 L of gas when sampling at a rate of
0.4 L/min. Sampling time (min) = 25 L / 0.4 L/min = 63 minutes
8.2.6 Field Recovery Test. The field recovery test provides a
test program-specific verification of the performance of the
combined sampling and analytical approach. Three sets of paired
samples, one of each pair which is spiked with a known level of Hg,
are collected and analyzed and the average recovery of the spiked
samples is used to verify performance of the measurement system
under field conditions during that test program. The conduct of
this test requires an estimate or confirmation of the stack Hg
concentrations at the time of testing.
8.2.6.1 Calculation of Pre-sampling Spiking Level. Determine the
sorbent trap spiking level for the field recovery test using
estimates of the stack Hg concentration, the target sample flow
rate, and the planned sample duration. First, determine the Hg mass
expected to be collected in section 1 of the sorbent trap. The
pre-sampling spike must be within 50 to 150 percent of this
expected mass.
Example calculation:For an expected stack Hg concentration of 5
ug/m 3 (ng/L) a target sample rate of 0.40 liters/min, and a sample
duration of 1 hour: (0.40 L/min) * (60 min) * (5ng/L) = 120 ng
A Hg spike of 60 to 180 ng (50-150% of 120 ng) would be
appropriate.
8.2.6.2 Procedures. Set up two identical sampling trains. One of
the sampling trains shall be designated the spiked train and the
other the unspiked train. Spike Hg 0 onto the front section of the
sorbent trap in the spiked train before sampling. The mass of Hg
spiked shall be 50 to 150 percent of the mass expected to be
collected with the unspiked train. Sample the stack gas with the
two trains simultaneously using the same procedures as for the
field samples (see section 8.3). The total sample volume must be
within ±20 percent of the target sample volume for the field sample
test runs. Analyze the sorbent traps from the two trains utilizing
the same analytical procedures and instrumentation as for the field
samples (see section 11.0). Determine the fraction of spiked Hg
recovered (R) using the equations in section 12.7. Repeat this
procedure for a total of three runs. Report the individual R values
in the test report; the average of the three R values must be
between 85 and 115 percent.
Note to section 8.2.6.2:
It is acceptable to perform the field recovery test concurrent
with actual test runs (e.g., through the use of a quad probe). It
is also acceptable to use the field recovery test runs as test runs
for emissions testing or for the RATA of a Hg monitoring system
under subpart UUUUU of part 63 of this chapter and Performance
Specifications 12A and 12B in appendix B to this part, if certain
conditions are met. To determine whether a particular field
recovery test run may be used as a RATA run, subtract the mass of
the Hg 0 spike from the total Hg mass collected in sections 1 and 2
of the spiked trap. The difference represents the mass of Hg in the
stack gas sample. Divide this mass by the sample volume to obtain
the Hg concentration in the effluent gas stream, as measured with
the spiked trap. Compare this concentration to the corresponding Hg
concentration measured with the unspiked trap. If the paired trains
meet the relative deviation and other applicable data validation
criteria in Table 9-1, then the average of the two Hg
concentrations may be used as an emissions test run value or as the
reference method value for a RATA run.
8.3 Sampling. This section describes the procedures and criteria
for collecting the field samples for analysis. As noted in section
8.2.6, the field recovery test samples are also collected using
these procedures.
8.3.1 Pre-test leak check. Perform a leak check of the sampling
system with the sorbent traps in place. For each of the paired
sampling trains, draw a vacuum in the train, and adjust the vacuum
to ∼15″ Hg; and, using the gas flow meter, determine leak rate. The
leak rate for an individual train must not exceed 4 percent of the
target sampling rate. Once the leak check passes this criterion,
carefully release the vacuum in the sample train, then seal the
sorbent trap inlet until the probe is ready for insertion into the
stack or duct.
8.3.2 Determination of Flue Gas Characteristics. Determine or
measure the flue gas measurement environment characteristics (gas
temperature, static pressure, gas velocity, stack moisture, etc.)
in order to determine ancillary requirements such as probe heating
requirements (if any), initial sampling rate, moisture management,
etc.
8.3.3 Sample Collection
8.3.3.1 Remove the plug from the end of each sorbent trap and
store each plug in a clean sorbent trap storage container. Remove
the stack or duct port cap and insert the probe(s). Secure the
probe(s) and ensure that no leakage occurs between the duct and
environment.
8.3.3.2 Record initial data including the sorbent trap ID, date,
and the run start time.
8.3.3.3 Record the initial gas flow meter reading, stack
temperature, meter temperatures (if needed), and any other
appropriate information, before beginning sampling. Begin sampling
and target a sampling flow rate similar to that for the field
recovery test. Then, at regular intervals (≤5 minutes) during the
sampling period, record the date and time, the sample flow rate,
the gas meter reading, the stack temperature, the flow meter
temperatures (if using a dry gas meter), temperatures of heated
equipment such as the vacuum lines and the probes (if heated), and
the sampling system vacuum readings. Adjust the sampling flow rate
as necessary to maintain the initial sample flow rate. Ensure that
the total volume sampled for each run is within 20 percent of the
total volume sampled for the field recovery test.
8.3.3.4 Data Recording. Obtain and record any essential
operating data for the facility during the test period, e.g., the
barometric pressure must be obtained for correcting sample volume
to standard conditions when using a dry gas meter. At the end of
the data collection period, record the final gas flow meter reading
and the final values of all other essential parameters.
8.3.3.5 Post-Test Leak Check. When sampling is completed, turn
off the sample pump, remove the probe(s) with sorbent traps from
the port, and carefully seal the end of each sorbent trap. Perform
another leak check of each sampling train with the sorbent trap in
place, at the maximum vacuum reached during the sampling period.
Record the leakage rates and vacuums. The leakage rate for each
train must not exceed 4 percent of the average sampling rate for
the data collection period. Following each leak check, carefully
release the vacuum in the sample train.
8.3.3.6 Sample Recovery. Recover each sampled sorbent trap by
removing it from the probe and sealing both ends. Wipe any
deposited material from the outside of the sorbent trap. Place the
sorbent trap into an appropriate sample storage container and
store/preserve in appropriate manner (see section 8.3.3.8).
8.3.3.7 Stack Gas Moisture Determination. If the moisture basis
of the measurements made with this method (dry) is different from
the moisture basis of either: (1) the applicable emission limit; or
(2) a Hg CEMS being evaluated for relative accuracy, you must
determine the moisture content of the flue gas and correct for
moisture using Method 4 in appendix A-3 to this part. If correction
of the measured Hg concentrations for moisture is required, at
least one Method 4 moisture determination shall be made during each
test run.
8.3.3.8 Sample Handling, Preservation, Storage, and Transport.
While the performance criteria of this approach provides for
verification of appropriate sample handling, it is still important
that the user consider, determine and plan for suitable sample
preservation, storage, transport, and holding times for these
measurements. Therefore, procedures in ASTM D6911-15 “Standard
Guide for Packaging and Shipping Environmental Samples for
Laboratory Analysis” (incorporated by reference-see 40 CFR 60.17)
shall be followed for all samples, where appropriate. To avoid Hg
contamination of the samples, special attention should be paid to
cleanliness during transport, field handling, sampling, recovery,
and laboratory analysis, as well as during preparation of the
sorbent cartridges. Collection and analysis of blank samples
(e.g., reagent, sorbent, field, etc.) is useful in verifying
the absence or source of contaminant Hg.
8.3.3.9 Sample Custody. Proper procedures and documentation for
sample chain of custody are critical to ensuring data integrity.
The chain of custody procedures in ASTM D4840-99 “Standard Guide
for Sampling Chain-of-Custody Procedures” shall be followed for all
samples (including field samples and blanks).
9.0 Quality Assurance and Quality Control
Table 9-1 summarizes the QA/QC performance criteria that are
used to validate the Hg emissions data from Method 30B sorbent trap
measurement systems.
Table 9-1 - Quality Assurance/Quality
Control Criteria for Method 30B
QA/QC test or
specification
Acceptance criteria
Frequency
Consequences if not met
Gas flow meter
calibration (At 3 settings or points)
Calibration factor (Yi) at
each flow rate must be within ±2% of the average value (Y)
Prior to initial use and when
post-test check is not within ±5% of Y
Recalibrate at 3 points until
the acceptance criteria are met.
Gas flow meter
post-test calibration check (Single-point)
Calibration factor (Yi) must
be within ±5% of the Y value from the most recent 3-point
calibration
After each field test. For
mass flow meters, must be done on-site, using stack gas
Recalibrate gas flow meter at
3 points to determine a new value of Y. For mass flow meters, must
be done on-site, using stack gas. Apply the new Y value to the
field test data.
Temperature sensor
calibration
Absolute temperature measures
by sensor within ±1.5% of a reference sensor
Prior to initial use and
before each test thereafter
Recalibrate; sensor may not be
used until specification is met.
Barometer
calibration
Absolute pressure measured by
instrument within ±10 mm Hg of reading with a mercury barometer or
NIST traceable barometer
Prior to initial use and
before each test thereafter
Recalibrate; instrument may
not be used until specification is met.
Pre-test leak
check
≤4% of target sampling
rate
Prior to sampling
Sampling shall not commence
until the leak check is passed.
Post-test leak
check
≤4% of average sampling
rate
After sampling
Sample invalidated.*
Analytical matrix
interference test (wet chemical analysis, only)
Prior to analyzing any field
samples; repeat for each type of sorbent used
Field sample results not
validated.
Analytical bias
test
Average recovery between 90%
and 110% for Hg 0 and HgCl2 at each of the 2 spike
concentration levels
Prior to analyzing field
samples and prior to use of new sorbent media
Field samples shall not be
analyzed until the percent recovery criteria has been met.
Multipoint
analyzer calibration
Each analyzer reading within
±10% of true value and r 2≥0.99
On the day of analysis, before
analyzing any samples
Recalibrate until
successful.
Analysis of
independent calibration standard
Within ±10% of true value
Following daily calibration,
prior to analyzing field samples
Recalibrate and repeat
independent standard analysis until successful.
Analysis of
continuing calibration verification standard (CCVS)
Within ±10% of true value
Following daily calibration,
after analyzing ≤10 field samples, and at end of each set of
analyses
Recalibrate and repeat
independent standard analysis, reanalyze samples until successful,
if possible; for destructive techniques, samples invalidated.
Test run total
sample volume
Within ±20% of total volume
sampled during field recovery test
Each individual sample
Sample invalidated.
Sorbent trap
section 2 breakthrough
For compliance/emissions
testing:
Every sample
Sample invalidated.*
≤10% of section 1 Hg mass for
Hg concentrations >1 µg/dscm;
≤20% of section 1 Hg mass for
Hg concentrations ≤1 µg/dscm
≤50% of section 1 Hg mass if
the stack Hg concentration is ≤30% of the Hg concentration that is
equivalent to the applicable emission limit
For relative accuracy
testing:
≤10% of section 1 Hg mass for
Hg concentrations >1 µg/dscm;
≤20% of section 1 Hg mass for
Hg concentrations ≤1 µg/dscm and >0.5 µg/dscm;
≤50% of section 1 Hg mass for
Hg concentrations ≤0.5 µg/dscm >0.1 µg/dscm;
no criterion for Hg
concentrations ≤0.1 µg/dscm (must meet all other QA/QC
specifications)
Paired sorbent
trap agreement
≤10% Relative Deviation (RD)
mass for Hg concentrations >1 µg/dscm;
Every run
Run invalidated.*
≤20% RD or ≤0.2 µg/dscm
absolute difference for Hg concentrations ≤1 µg/dscm
Sample
analysis
Within valid calibration range
(within calibration curve)
All Section 1 samples where
stack Hg concentration is ≥0.02 µg/dscm except in case where stack
Hg concentration is ≤30% of the applicable emission limit
Reanalyze at more concentrated
level if possible, samples invalidated if not within calibrated
range.
Sample
analysis
Within bounds of Hg
0 and HgCl2 Analytical Bias Test
All Section 1 samples where
stack Hg concentration is ≥0.5 µg/dscm
Expand bounds of Hg
0 and HgCl2 Analytical Bias Test; if not successful,
samples invalidated.
Field recovery
test
Average recovery between 85%
and 115% for Hg 0
Once per field test
Field sample runs not
validated without successful field recovery test.
* And data from the pair of sorbent traps
are also invalidated.
10.0 Calibration and Standardization
10.1 Only NIST-certified and NIST-traceable calibration
standards (i.e., calibration gases, solutions, etc.) shall be used
for the spiking and analytical procedures in this method.
10.2 Gas Flow Meter Calibration.
10.2.1 Preliminaries. The manufacturer or equipment supplier of
the gas flow meter should perform all necessary set-up, testing,
programming, etc., and should provide the end user with any
necessary instructions, to ensure that the meter will give an
accurate readout of dry gas volume in standard cubic meters for
this method.
10.2.2 Initial Calibration. Prior to its initial use, a
calibration of the gas flow meter shall be performed. The initial
calibration may be done by the manufacturer, by the equipment
supplier, or by the end user. If the flow meter is volumetric in
nature (e.g., a dry gas meter), the manufacturer or end user
may perform a direct volumetric calibration using any gas. For a
mass flow meter, the manufacturer, equipment supplier, or end user
may calibrate the meter using either: (1) A bottled gas mixture
containing 12 ±0.5% CO2, 7 ±0.5% O2, and balance N2 (when this
method is applied to coal-fired boilers); (2) a bottled gas mixture
containing CO2, O2, and N2 in proportions representative of the
expected stack gas composition; or (3) the actual stack gas.
10.2.2.1 Initial Calibration Procedures. Determine an average
calibration factor (Y) for the gas flow meter by calibrating it at
three sample flow rate settings covering the range of sample flow
rates at which the sampling system will be operated. You may either
follow the procedures in section 10.3.1 of Method 5 in appendix A-3
to this part or in section 16 of Method 5 in appendix A-3 to this
part. If a dry gas meter is being calibrated, use at least five
revolutions of the meter at each flow rate.
10.2.2.2 Alternative Initial Calibration Procedures.
Alternatively, you may perform the initial calibration of the gas
flow meter using a reference gas flow meter (RGFM). The RGFM may
be: (1) A wet test meter calibrated according to section 10.3.1 of
Method 5 in appendix A-3 to this part; (2) a gas flow metering
device calibrated at multiple flow rates using the procedures in
section 16 of Method 5 in appendix A-3 to this part; or (3) a
NIST-traceable calibration device capable of measuring volumetric
flow to an accuracy of 1 percent. To calibrate the gas flow meter
using the RGFM, proceed as follows: While the Method 30B sampling
system is sampling the actual stack gas or a compressed gas mixture
that simulates the stack gas composition (as applicable), connect
the RGFM to the discharge of the system. Care should be taken to
minimize the dead volume between the gas flow meter being tested
and the RGFM. Concurrently measure dry stack gas volume with the
RGFM and the flow meter being calibrated for at least 10 minutes at
each of three flow rates covering the typical range of operation of
the sampling system. For each set of concurrent measurements,
record the total sample volume, in units of dry standard cubic
meters (dscm), measured by the RGFM and the gas flow meter being
tested.
10.2.2.3 Initial Calibration Factor. Calculate an individual
calibration factor Yi at each tested flow rate from section
10.2.2.1 or 10.2.2.2 of this method (as applicable) by taking the
ratio of the reference sample volume to the sample volume recorded
by the gas flow meter. Average the three Yi values, to determine Y,
the calibration factor for the flow meter. Each of the three
individual values of Yi must be within ±0.02 of Y. Except as
otherwise provided in sections 10.2.2.4 and 10.2.2.5 of this
method, use the average Y value from the initial 3-point
calibration to adjust subsequent gas volume measurements made with
the gas flow meter.
10.2.2.4 Pretest On-Site Calibration Check (Optional). For a
mass flow meter, if the most recent 3-point calibration of the flow
meter was performed using a compressed gas mixture, you may want to
conduct the following on-site calibration check prior to testing,
to ensure that the flow meter will accurately measure the volume of
the stack gas: While sampling stack gas, check the calibration of
the flow meter at one intermediate flow rate setting representative
of normal operation of the sampling system. If the pretest
calibration check shows that the value of Yi, the calibration
factor at the tested flow rate, differs from the current value of Y
by more than 5 percent, perform a full 3-point recalibration of the
meter using stack gas to determine a new value of Y, and (except as
otherwise provided in section 10.2.2.5 of this method) apply the
new Y value to the data recorded during the field test.
10.2.2.5 Post-Test Calibration Check. Check the calibration of
the gas flow meter following each field test at one intermediate
flow rate setting, either at, or in close proximity to, the average
sample flow rate during the field test. For dry gas meters, ensure
at least three revolutions of the meter during the calibration
check. For mass flow meters, this check must be performed before
leaving the test site, while sampling stack gas. If a one-point
calibration check shows that the value of Yi at the tested flow
rate differs by more than 5 percent from the current value of Y,
repeat the full 3-point calibration procedure to determine a new
value of Y, and apply the new Y value to the gas volume
measurements made with the gas flow meter during the field test
that was just completed. For mass flow meters, perform the 3-point
recalibration while sampling stack gas.
10.3 Thermocouples and Other Temperature Sensors. Use the
procedures and criteria in Section 10.3 of Method 2 in appendix A-1
to this part to calibrate in-stack temperature sensors and
thermocouples. Dial thermometers shall be calibrated against
mercury-in-glass thermometers or equivalent. Calibrations must be
performed prior to initial use and before each field test
thereafter. At each calibration point, the absolute temperature
measured by the temperature sensor must agree to within ±1.5
percent of the temperature measured with the reference sensor,
otherwise the sensor may not continue to be used.
10.4 Barometer. Calibrate against a mercury barometer or other
NIST-traceable barometer as per Section 10.6 of Method 5 in
appendix A-3 to this part. Calibration must be performed prior to
initial use and before each test program, and the absolute pressure
measured by the barometer must agree to within ±10 mm Hg of the
pressure measured by the mercury or other NIST-traceable barometer,
otherwise the barometer may not continue to be used.
10.5 Other Sensors and Gauges. Calibrate all other sensors and
gauges according to the procedures specified by the instrument
manufacturer(s).
10.6 Analytical System Calibration. See section 11.1 of this
method.
11.0 Analytical Procedures
The analysis of Hg in the field and quality control samples may
be conducted using any instrument or technology capable of
quantifying total Hg from the sorbent media and meeting the
performance criteria in this method. Because multiple analytical
approaches, equipment and techniques are appropriate for the
analysis of sorbent traps, it is not possible to provide detailed,
technique-specific analytical procedures. As they become available,
detailed procedures for a variety of candidate analytical
approaches will be posted at http://www.epa.gov/ttn/emc.
11.1 Analytical System Calibration. Perform a multipoint
calibration of the analyzer at three or more upscale points over
the desired quantitative range (multiple calibration ranges shall
be calibrated, if necessary). The field samples analyzed must fall
within a calibrated, quantitative range and meet the performance
criteria specified below. For samples suitable for aliquotting, a
series of dilutions may be needed to ensure that the samples fall
within a calibrated range. However, for sorbent media samples
consumed during analysis (e.g., when using thermal desorption
techniques), extra care must be taken to ensure that the analytical
system is appropriately calibrated prior to sample analysis. The
calibration curve range(s) should be determined such that the
levels of Hg mass expected to be collected and measured will fall
within the calibrated range. The calibration curve may be generated
by directly introducing standard solutions into the analyzer or by
spiking the standards onto the sorbent media and then introducing
into the analyzer after preparing the sorbent/standard according to
the particular analytical technique. For each calibration curve,
the value of the square of the linear correlation coefficient,
i.e., r 2, must be ≥0.99, and the analyzer response must be within
±10 percent of the reference value at each upscale calibration
point. Calibrations must be performed on the day of the analysis,
before analyzing any of the samples. Following calibration, an
independent standard shall be analyzed. The measured value of the
independently prepared standard must be within ±10 percent of the
expected value.
11.2 Sample Preparation. Carefully separate the sections of each
sorbent trap. Combine for analysis all materials associated with
each section; any supporting substrate that the sample gas passes
through prior to entering a media section (e.g., glass wool
separators, acid gas traps, etc.) must be analyzed with that
segment.
11.3 Field Sample Analyses. Analyze the sorbent trap samples
following the same procedures that were used for conducting the Hg
0 and HgCl2 analytical bias tests. The individual sections of the
sorbent trap and their respective components must be analyzed
separately (i.e., section 1 and its components, then section
2 and its components). All sorbent trap section 1 sample analyses
must be within the calibrated range of the analytical system as
specified in Table 9-1. For wet analyses, the sample can simply be
diluted to fall within the calibrated range. However, for the
destructive thermal analyses, samples that are not within the
calibrated range cannot be re-analyzed. As a result, the sample
cannot be validated, and another sample must be collected. It is
strongly suggested that the analytical system be calibrated over
multiple ranges so that thermally analyzed samples fall within the
calibrated range. The total mass of Hg measured in each sorbent
trap section 1 must also fall within the lower and upper mass
limits established during the initial Hg 0 and HgCl2 analytical
bias test. If a sample is analyzed and found to fall outside of
these limits, it is acceptable for an additional Hg 0 and HgCl2
analytical bias test to be performed that now includes this level.
However, some samples (e.g., the mass collected in trap section 2),
may have Hg levels so low that it may not be possible to quantify
them in the analytical system's calibrated range. Because a
reliable estimate of these low-level Hg measurements is necessary
to fully validate the emissions data, the MDL (see section 8.2.2.1
of this method) is used to establish the minimum amount that can be
detected and reported. If the measured mass or concentration is
below the lowest point in the calibration curve and above the MDL,
the analyst must estimate the mass or concentration of the sample
based on the analytical instrument response relative to an
additional calibration standard at a concentration or mass between
the MDL and the lowest point in the calibration curve. This is
accomplished by establishing a response factor (e.g., area counts
per Hg mass or concentration) and estimating the amount of Hg
present in the sample based on the analytical response and this
response factor.
Example:The analysis of a particular sample results in a measured
mass above the MDL, but below the lowest point in the calibration
curve which is 10 ng. An MDL of 1.3 ng Hg has been established by
the MDL study. A calibration standard containing 5 ng of Hg is
analyzed and gives an analytical response of 6,170 area counts,
which equates to a response factor of 1,234 area counts/ng Hg. The
analytical response for the sample is 4,840 area counts. Dividing
the analytical response for the sample (4,840 area counts) by the
response factor gives 3.9 ng Hg, which is the estimated mass of Hg
in the sample.
11.4 Analysis of Continuing Calibration Verification Standard
(CCVS). After no more than 10 samples and at the end of each set of
analyses, a continuing calibration verification standard must be
analyzed. The measured value of the continuing calibration standard
must be within ±10 percent of the expected value.
11.5 Blanks. The analysis of blanks is optional. The analysis of
blanks is useful to verify the absence of, or an acceptable level
of, Hg contamination. Blank levels should be considered when
quantifying low Hg levels and their potential contribution to
meeting the sorbent trap section 2 breakthrough requirements;
however, correcting sorbent trap results for blank levels is
prohibited.
12.0 Calculations and Data Analysis
You must follow the procedures for calculation and data analysis
listed in this section.
12.1 Nomenclature. The terms used in the equations are defined
as follows:
B = Breakthrough (%). Bws = Moisture content of sample gas as
measured by Method 4, percent/100. Ca = Concentration of Hg for the
sample collection period, for sorbent trap “a” (µg/dscm). Cb =
Concentration of Hg for the sample collection period, for sorbent
trap “b” (µg/dscm). Cd = Hg concentration, dry basis (µg/dscm).
Crec = Concentration of spiked compound measured (µg/m 3). Cw = Hg
concentration, wet basis (µg/m 3). m1 = Mass of Hg measured on
sorbent trap section 1 (µg). m2 = Mass of Hg measured on sorbent
trap section 2 (µg). mrecovered = Mass of spiked Hg recovered in
Analytical Bias or Field Recovery Test (µg). ms = Total mass of Hg
measured on spiked trap in Field Recovery Test (µg). mspiked = Mass
of Hg spiked in Analytical Bias or Field Recovery Test (µg). mu =
Total mass of Hg measured on unspiked trap in Field Recovery Test
(µg). R = Percentage of spiked mass recovered (%). RD = Relative
deviation between the Hg concentrations from traps “a” and “b” (%).
vs = Volume of gas sampled, spiked trap in Field Recovery Test
(dscm). Vt = Total volume of dry gas metered during the collection
period (dscm); for the purposes of this method, standard
temperature and pressure are defined as 20 °C and 760 mm Hg,
respectively. vu = Volume of gas sampled, unspiked trap in Field
Recovery Test (dscm).
12.2 Calculation of Spike Recovery (Analytical Bias Test).
Calculate the percent recovery of Hg 0 and HgCl2 using Equation
30B-1.
12.3 Calculation of Breakthrough. Use Equation 30B-2 to
calculate the percent breakthrough to the second section of the
sorbent trap.
12.4 Calculation of Hg Concentration. Calculate the Hg
concentration measured with sorbent trap “a”, using Equation
30B-3.
For sorbent trap “b”, replace “Ca ” with “Cb ” in Equation
30B-3. Report the average concentration, i.e., 1/2 (Ca + Cb).
12.5 Moisture Correction. Use Equation 30B-4 if your
measurements need to be corrected to a wet basis.
12.6 Calculation of Paired Trap Agreement. Calculate the
relative deviation (RD) between the Hg concentrations measured with
the paired sorbent traps using Equation 30B-5.
12.7 Calculation of Measured Spike Hg Concentration (Field
Recovery Test). Calculate the measured spike concentration using
Equation 30B-6.
Then calculate the spiked Hg recovery, R, using Equation
30B-7.
13.0 Method Performance
How do I validate my data? Measurement data are validated using
initial, one-time laboratory tests coupled with test
program-specific tests and procedures. The analytical matrix
interference test and the Hg 0 and HgCl2 analytical bias test
described in section 8.2 are used to verify the appropriateness of
the selected analytical approach(es) as well as define the valid
working ranges for sample analysis. The field recovery test serves
to verify the performance of the combined sampling and analysis as
applied for each test program. Field test samples are validated by
meeting the above requirements as well as meeting specific sampling
requirements (i.e., leak checks, paired train agreement, total
sample volume agreement with field recovery test samples) and
analytical requirements (i.e., valid calibration curve, continuing
calibration performance, sample results within calibration curve
and bounds of Hg 0 and HgCl2 analytical bias test). Complete data
validation requirements are summarized in Table 9-1.
1. EPA Traceability Protocol for Qualification and Certification
of Elemental Mercury Gas Generators, expected publication date
December 2008, see www.epa.gov/ttn/emc.
2. EPA Traceability Protocol for Qualification and Certification
of Oxidized Mercury Gas Generators, expected publication date
December 2008, see www.epa.gov/ttn/emc.
3. EPA Traceability Protocol for Assay and Certification of
Gaseous Calibration Standards, expected revision publication date
December 2008, see www.epa.gov/ttn/emc.
17.0 Figures and Tables [36 FR 24877, Dec.
23, 1971] Editorial Note:For Federal Register citations affecting
appendix A-8 to part 60, see the List of CFR sections Affected,
which appears in the Finding Aids section of the printed volume and
at www.govinfo.gov.
Appendix B to Part 60 - Performance Specifications
40:9.0.1.1.1.0.1.1.9 : Appendix B
Appendix B to Part 60 - Performance Specifications Performance
Specification 1 - Specifications and test procedures for continuous
opacity monitoring systems in stationary sources Performance
Specification 2 - Specifications and Test Procedures for SO2 and
NOX Continuous Emission Monitoring Systems in Stationary Sources
Performance Specification 3 - Specifications and Test Procedures
for O2 and CO2 Continuous Emission Monitoring Systems in Stationary
Sources Performance Specification 4 - Specifications and Test
Procedures for Carbon Monoxide Continuous Emission Monitoring
Systems in Stationary Sources Performance Specification 4A -
Specifications and Test Procedures for Carbon Monoxide Continuous
Emission Monitoring Systems in Stationary Sources Performance
Specification 4B - Specifications and Test Procedures for Carbon
Monoxide and Oxygen Continuous Monitoring Systems in Stationary
Sources Performance Specification 5 - Specifications and Test
Procedures for TRS Continuous Emission Monitoring Systems in
Stationary Sources Performance Specification 6 - Specifications and
Test Procedures for Continuous Emission Rate Monitoring Systems in
Stationary Sources Performance Specification 7 - Specifications and
Test Procedures for Hydrogen Sulfide Continuous Emission Monitoring
Systems in Stationary Sources Performance Specification 8 -
Performance Specifications for Volatile Organic Compound Continuous
Emission Monitoring Systems in Stationary Sources Performance
Specification 8A - Specifications and Test Procedures for Total
Hydrocarbon Continuous Monitoring Systems in Stationary Sources
Performance Specification 9 - Specifications and Test Procedures
for Gas Chromatographic Continuous Emission Monitoring Systems in
Stationary Sources Performance Specification 11 - Specifications
and Test Procedures for Particulate Matter Continuous Emission
Monitoring Systems at Stationary Sources Performance Specification
12A - Specifications and Text Procedures for Total Vapor Phase
Mercury Continuous Emission Monitoring Systems in Stationary
Sources Performance Specification 12B - Specifications and Test
Procedures for Monitoring Total Vapor Phase Mercury Emissions From
Stationary Sources Using A Sorbent Trap Monitoring System
Performance Specification 15 - Performance Specification for
Extractive FTIR Continuous Emissions Monitor Systems in Stationary
Sources Performance Specification 16 - Specifications and Test
Procedures for Predictive Emission Monitoring Systems in Stationary
Sources Performance Specification 17 [Reserved] Performance
Specification 18 - Performance Specifications and Test Procedures
for Gaseous Hydrogen Chloride (HCl) Continuous Emission Monitoring
Systems at Stationary Sources PS-18 - Appendix A Standard Addition
Procedures Performance Specification 1 - Specifications and Test
Procedures for Continuous Opacity Monitoring Systems in Stationary
Sources 1.0 What Is the Purpose and Applicability of Performance
Specification 1?
Performance Specification 1 (PS-1) provides (1) requirements for
the design, performance, and installation of a continuous opacity
monitoring system (COMS) and (2) data computation procedures for
evaluating the acceptability of a COMS. It specifies activities for
two groups (1) the owner or operator and (2) the opacity monitor
manufacturer.
1.1 Measurement Parameter. PS-1 covers the instrumental
measurement of opacity caused by attenuation of projected light due
to absorption and scatter of the light by particulate matter in the
effluent gas stream.
1.2 What COMS must comply with PS-1? If you are an owner or
operator of a facility with a COMS as a result of this Part, then
PS-1 applies to your COMS if one of the following is true:
(1) Your facility has a new COMS installed after February 6,
2001; or
(2) Your COMS is replaced, relocated, or substantially
refurbished (in the opinion of the regulatory authority) after
February 6, 2001; or
(3) Your COMS was installed before February 6, 2001 and is
specifically required by regulatory action other than the
promulgation of PS-1 to be recertified.
If you are an opacity monitor manufacturer, then paragraph 8.2
applies to you.
1.3 Does PS-1 apply to a facility with an applicable opacity
limit less than 10 percent? If you are an owner or operator of a
facility with a COMS as a result of this Part and the applicable
opacity limit is less than 10 percent, then PS-1 applies to your
COMS as described in section 1.2; taking into account (through
statistical procedures or otherwise) the uncertainties associated
with opacity measurements, and following the conditions for
attenuators selection for low opacity applications as outlined in
section 8.1(3)(ii). At your option, you, the source owner or
operator, may select to establish a reduced full scale range of no
less than 50 percent opacity instead of the 80 percent as
prescribed in section 3.5, if the applicable opacity limit for your
facility is less than 10 percent. The EPA recognizes that reducing
the range of the analyzer to 50 percent does not necessarily result
in any measurable improvement in measurement accuracy at opacity
levels less than 10 percent; however, it may allow improved chart
recorder interpretation.
1.4 What data uncertainty issues apply to COMS data? The
measurement uncertainties associated with COMS data result from
several design and performance factors including limitations on the
availability of calibration attenuators for opacities less than
about 6 percent (3 percent for single-pass instruments),
calibration error tolerances, zero and upscale drift tolerances,
and allowance for dust compensation that are significant relative
to low opacity levels. The full scale requirements of this PS may
also contribute to measurement uncertainty for opacity measurements
where the applicable limits are below 10 percent opacity.
2.0 What Are the Basic Requirements of PS-1?
PS-1 requires (1) opacity monitor manufacturers comply with a
comprehensive series of design and performance specifications and
test procedures to certify opacity monitoring equipment before
shipment to the end user, (2) the owner or operator to follow
installation guidelines, and (3) the owner or operator to conduct a
set of field performance tests that confirm the acceptability of
the COMS after it is installed.
2.1 ASTM D6216-12 (incorporated by reference, see § 60.17) is
the reference for design specifications, manufacturer's performance
specifications, and test procedures. The opacity monitor
manufacturer must periodically select and test an opacity monitor,
that is representative of a group of monitors produced during a
specified period or lot, for conformance with the design
specifications in ASTM D6216-12. The opacity monitor manufacturer
must test each opacity monitor for conformance with the
manufacturer's performance specifications in ASTM D6216-12. Note:
If the initial certification of the opacity monitor occurred before
November 14, 2018 using D6216-98, D6216-03, or D6216-07, it is not
necessary to recertify using D6216-12.
2.2 section 8.1(2) provides guidance for locating an opacity
monitor in vertical and horizontal ducts. You are encouraged to
seek approval for the opacity monitor location from the appropriate
regulatory authority prior to installation.
2.3 After the COMS is installed and calibrated, the owner or
operator must test the COMS for conformance with the field
performance specifications in PS-1.
3.0 What Special Definitions Apply to PS-1?
3.1 All definitions and discussions from section 3 of ASTM
D6216-12 are applicable to PS-1.
3.2 Centroid Area. A concentric area that is
geometrically similar to the stack or duct cross-section and is no
greater than 1 percent of the stack or duct cross-sectional
area.
3.3 Data Recorder. That portion of the installed COMS
that provides a permanent record of the opacity monitor output in
terms of opacity. The data recorder may include automatic data
reduction capabilities.
3.4 External Audit Device. The inherent design,
equipment, or accommodation of the opacity monitor allowing the
independent assessment of the COMS's calibration and operation.
3.5 Full Scale. The maximum data display output of the
COMS. For purposes of recordkeeping and reporting, full scale will
be greater than 80 percent opacity.
3.6 Operational Test Period. A period of time (168 hours)
during which the COMS is expected to operate within the established
performance specifications without any unscheduled maintenance,
repair, or adjustment.
3.7 Primary Attenuators. Those devices (glass or grid
filter that reduce the transmission of light) calibrated according
to procedures in section 7.1.
3.8 Secondary Attenuators. Those devices (glass or grid
filter that reduce the transmission of light) calibrated against
primary attenuators according to procedures in section 7.2.
3.9 System Response Time. The amount of time the COMS
takes to display 95 percent of a step change in opacity on the COMS
data recorder.
4.0 Interferences. Water Droplets 5.0 What Do I Need To Know To
Ensure the Safety of Persons Using PS-1?
The procedures required under PS-1 may involve hazardous
materials, operations, and equipment. PS-1 does not purport to
address all of the safety problems associated with these
procedures. Before performing these procedures, you must establish
appropriate safety and health practices, and you must determine the
applicable regulatory limitations. You should consult the COMS
user's manual for specific precautions to take.
6.0 What Equipment and Supplies Do I Need?
6.1 Continuous Opacity Monitoring System. You, as owner
or operator, are responsible for purchasing an opacity monitor that
meets the specifications of ASTM D6216-12, including a suitable
data recorder or automated data acquisition handling system.
Example data recorders include an analog strip chart recorder or
more appropriately an electronic data acquisition and reporting
system with an input signal range compatible with the analyzer
output.
6.2 Calibration Attenuators. You, as owner or operator,
are responsible for purchasing a minimum of three calibration
attenuators that meet the requirements of PS-1. Calibration
attenuators are optical filters with neutral spectral
characteristics. Calibration attenuators must meet the requirements
in section 7 and must be of sufficient size to attenuate the entire
light beam received by the detector of the COMS. For
transmissometers operating over a narrow bandwidth (e.g.,
laser), a calibration attenuator's value is determined for the
actual operating wavelengths of the transmissometer. Some filters
may not be uniform across the face. If errors result in the daily
calibration drift or calibration error test, you may want to
examine the across-face uniformity of the filter.
6.3 Calibration Spectrophotometer. Whoever calibrates the
attenuators must have a spectrophotometer that meets the following
minimum design specifications:
Parameter
Specification
Wavelength
range
300-800 nm.
Detector angle of
view
<10°.
Accuracy
<0.5% transmittance, NIST
traceable calibration.
7.0 What Reagents and Standards Do I Need?
You will need to use attenuators (i.e., neutral density
filters) to check the daily calibration drift and calibration error
of a COMS. Attenuators are designated as either primary or
secondary based on how they are calibrated.
7.1 Attenuators are designated primary in one of two ways:
(1) They are calibrated by NIST; or
(2) They are calibrated on a 6-month frequency through the
assignment of a luminous transmittance value in the following
manner:
(i) Use a spectrophotometer meeting the specifications of
section 6.3 to calibrate the required filters. Verify the
spectrophotometer calibration through use of a NIST 930D Standard
Reference Material (SRM). A SRM 930D consists of three neutral
density glass filters and a blank, each mounted in a cuvette. The
wavelengths and temperature to be used in the calibration are
listed on the NIST certificate that accompanies the reported
values. Determine and record a transmittance of the SRM values at
the NIST wavelengths (three filters at five wavelengths each for a
total of 15 determinations). Calculate a percent difference between
the NIST certified values and the spectrophotometer response. At
least 12 of the 15 differences (in percent) must be within ±0.5
percent of the NIST SRM values. No difference can be greater than
±1.0 percent. Recalibrate the SRM or service the spectrophotometer
if the calibration results fail the criteria.
(ii) Scan the filter to be tested and the NIST blank from
wavelength 380 to 780 nm, and record the spectrophotometer percent
transmittance responses at 10 nm intervals. Test in this sequence:
blank filter, tested filter, tested filter rotated 90 degrees in
the plane of the filter, blank filter. Calculate the average
transmittance at each 10 nm interval. If any pair of the tested
filter transmittance values (for the same filter and wavelength)
differ by more than ±0.25 percent, rescan the tested filter. If the
filter fails to achieve this tolerance, do not use the filter in
the calibration tests of the COMS.
(iii) Correct the tested filter transmittance values by dividing
the average tested filter transmittance by the average blank filter
transmittance at each 10 nm interval.
(iv) Calculate the weighted (to the response of the human eye),
tested filter transmittance by multiplying the transmittance value
by the corresponding response factor shown in table 1-1, to obtain
the Source C Human Eye Response.
(v) Recalibrate the primary attenuators semi-annually if they
are used for the required calibration error test. Recalibrate the
primary attenuators annually if they are used only for calibration
of secondary attenuators.
7.2 Attenuators are designated secondary if the filter
calibration is done using a laboratory-based transmissometer.
Conduct the secondary attenuator calibration using a
laboratory-based transmissometer calibrated as follows:
(i) Use at least three primary filters of nominal luminous
transmittance 50, 70 and 90 percent, calibrated as specified in
section 7.1(2)(i), to calibrate the laboratory-based
transmissometer. Determine and record the slope of the calibration
line using linear regression through zero opacity. The slope of the
calibration line must be between 0.99 and 1.01, and the
laboratory-based transmissometer reading for each primary filter
must not deviate by more than ±2 percent from the linear regression
line. If the calibration of the laboratory-based transmissometer
yields a slope or individual readings outside the specified ranges,
secondary filter calibrations cannot be performed. Determine the
source of the variations (either transmissometer performance or
changes in the primary filters) and repeat the transmissometer
calibration before proceeding with the attenuator calibration.
(ii) Immediately following the laboratory-based transmissometer
calibration, insert the secondary attenuators and determine and
record the percent effective opacity value per secondary attenuator
from the calibration curve (linear regression line).
(iii) Recalibrate the secondary attenuators semi-annually if
they are used for the required calibration error test.
8.0 What Performance Procedures Are Required To Comply With PS-1?
Procedures to verify the performance of the COMS are divided
into those completed by the owner or operator and those completed
by the opacity monitor manufacturer.
8.1 What procedures must I follow as the Owner or Operator?
(1) You must purchase an opacity monitor that complies with ASTM
D6216-12 and obtain a certificate of conformance from the opacity
monitor manufacturer.
(2) You must install the opacity monitor at a location where the
opacity measurements are representative of the total emissions from
the affected facility. You must meet this requirement by choosing a
measurement location and a light beam path as follows:
(i) Measurement Location. Select a measurement location that is
(1) at least 4 duct diameters downstream from all particulate
control equipment or flow disturbance, (2) at least 2 duct
diameters upstream of a flow disturbance, (3) where condensed water
vapor is not present, and (4) accessible in order to permit
maintenance. Alternatively, you may select a measurement location
specified in paragraph 8.1(2)(ii) or 8.1(2)(iii).
(ii) Light Beam Path. Select a light beam path that passes
through the centroidal area of the stack or duct. Also, you must
follow these additional requirements or modifications for these
measurement locations:
If your measurement location
is in a:
And is:
Then use a light beam path
that is:
1. Straight
vertical section of stack or duct
Less than 4 equivalent
diameters downstream from a bend
In the plane defined by the
upstream bend (see figure 1-1).
2. Straight
vertical section of stack or duct
Less than 4 equivalent
diameters upstream from a bend
In the plane defined by the
downstream bend (see figure 1-2).
3. Straight
vertical section of stack or duct
Less than 4 equivalent
diameters downstream and is also less than 1 diameter upstream from
a bend
In the plane defined by the
upstream bend (see figure 1-3).
4. Horizontal
section of stack or duct
At least 4 equivalent
diameters downstream from a vertical bend
In the horizontal plane that
is between 1/3 and 1/2 the distance up the vertical axis from the
bottom of the duct (see figure 1-4).
5. Horizontal
section of duct
Less than 4 equivalent
diameters downstream from a vertical bend
In the horizontal plane that
is between 1/2 and 2/3 the distance up the vertical axis from the
bottom of the duct for upward flow in the vertical section, and is
between 1/3 and 1/2 the distance up the vertical axis from the
bottom of the duct for downward flow (figure 1-5).
(iii) Alternative Locations and Light Beam Paths. You may select
locations and light beam paths, other than those cited above, if
you demonstrate, to the satisfaction of the Administrator or
delegated agent, that the average opacity measured at the
alternative location or path is equivalent to the opacity as
measured at a location meeting the criteria of sections 8.1(2)(i)
and 8.1(2)(ii). The opacity at the alternative location is
considered equivalent if (1) the average opacity value measured at
the alternative location is within ±10 percent of the average
opacity value measured at the location meeting the installation
criteria, and (2) the difference between any two average opacity
values is less than 2 percent opacity (absolute). You use the
following procedure to conduct this demonstration: simultaneously
measure the opacities at the two locations or paths for a minimum
period of time (e.g., 180-minutes) covering the range of
normal operating conditions and compare the results. The opacities
of the two locations or paths may be measured at different times,
but must represent the same process operating conditions. You may
use alternative procedures for determining acceptable locations if
those procedures are approved by the Administrator.
(3) Field Audit Performance Tests. After you install the COMS,
you must perform the following procedures and tests on the
COMS.
(i) Optical Alignment Assessment. Verify and record that all
alignment indicator devices show proper alignment. A clear
indication of alignment is one that is objectively apparent
relative to reference marks or conditions.
(ii) Calibration Error Check. Conduct a three-point calibration
error test using three calibration attenuators that produce outlet
pathlength corrected, single-pass opacity values shown in ASTM
D6216-12, section 7.5. If your applicable limit is less than 10
percent opacity, use attenuators as described in ASTM D6216-12,
section 7.5 for applicable standards of 10 to 19 percent opacity.
Confirm the external audit device produces the proper zero value on
the COMS data recorder. Separately, insert each calibration
attenuators (low, mid, and high-level) into the external audit
device. While inserting each attenuator, (1) ensure that the entire
light beam passes through the attenuator, (2) minimize interference
from reflected light, and (3) leave the attenuator in place for at
least two times the shortest recording interval on the COMS data
recorder. Make a total of five nonconsecutive readings for each
attenuator. At the end of the test, correlate each attenuator
insertion to the corresponding value from the data recorder.
Subtract the single-pass calibration attenuator values corrected to
the stack exit conditions from the COMS responses. Calculate the
arithmetic mean difference, standard deviation, and confidence
coefficient of the five measurements value using equations 1-3,
1-4, and 1-5. Calculate the calibration error as the sum of the
absolute value of the mean difference and the 95 percent confidence
coefficient for each of the three test attenuators using equation
1-6. Report the calibration error test results for each of the
three attenuators.
(iii) System Response Time Check. Using a high-level calibration
attenuator, alternately insert the filter five times and remove it
from the external audit device. For each filter insertion and
removal, measure the amount of time required for the COMS to
display 95 percent of the step change in opacity on the COMS data
recorder. For the upscale response time, measure the time from
insertion to display of 95 percent of the final, steady upscale
reading. For the downscale response time, measure the time from
removal to display 5 percent of the initial upscale reading.
Calculate the mean of the five upscale response time measurements
and the mean of the five downscale response time measurements.
Report both the upscale and downscale response times.
(iv) Averaging Period Calculation and Recording Check. After the
calibration error check, conduct a check of the averaging period
calculation (e.g., 6-minute integrated average). Consecutively
insert each of the calibration error check attenuators (low, mid,
and high-level) into the external audit device for a period of two
times the averaging period plus 1 minute (e.g., 13 minutes for a
6-minute averaging period). Compare the path length corrected
opacity value of each attenuator to the valid average value
calculated by the COMS data recording device for that
attenuator.
(4) Operational Test Period. Before conducting the operational
testing, you must have successfully completed the field audit tests
described in sections 8.1(3)(i) through 8.1(3)(iv). Then, you
operate the COMS for an initial 168-hour test period while the
source is operating under normal operating conditions. If normal
operations contain routine source shutdowns, include the source's
down periods in the 168-hour operational test period. However, you
must ensure that the following minimum source operating time is
included in the operational test period: (1) For a batch operation,
the operational test period must include at least one full cycle of
batch operation during the 168-hour period unless the batch
operation is longer than 168 hours or (2) for continuous operating
processes, the unit must be operating for at least 50 percent of
the 168-hour period. Except during times of instrument zero and
upscale calibration drift checks, you must analyze the effluent gas
for opacity and produce a permanent record of the COMS output.
During this period, you may not perform unscheduled maintenance,
repair, or adjustment to the COMS. Automatic zero and calibration
adjustments (i.e., intrinsic adjustments), made by the COMS
without operator intervention or initiation, are allowable at any
time. At the end of the operational test period, verify and record
that the COMS optical alignment is still correct. If the test
period is interrupted because of COMS failure, record the time when
the failure occurred. After the failure is corrected, you restart
the 168-hour period and tests from the beginning (0-hour). During
the operational test period, perform the following test
procedures:
(i) Zero Calibration Drift Test. At the outset of the 168-hour
operational test period and at each 24-hour interval, the automatic
calibration check system must initiate the simulated zero device to
allow the zero drift to be determined. Record the COMS response to
the simulated zero device. After each 24-hour period, subtract the
COMS zero reading from the nominal value of the simulated zero
device to calculate the 24-hour zero drift (ZD). At the end of the
168-hour period, calculate the arithmetic mean, standard deviation,
and confidence coefficient of the 24-hour ZDs using equations 1-3,
1-4, and 1-5. Calculate the sum of the absolute value of the mean
and the absolute value of the confidence coefficient using equation
1-6, and report this value as the 24-hour ZD error.
(ii) Upscale Calibration Drift Test. At each 24-hour interval
after the simulated zero device value has been checked, check and
record the COMS response to the upscale calibration device. After
each 24-hour period, subtract the COMS upscale reading from the
nominal value of the upscale calibration device to calculate the
24-hour calibration drift (CD). At the end of the 168-hour period,
calculate the arithmetic mean, standard deviation, and confidence
coefficient of the 24-hour CD using equations 1-3, 1-4, and 1-5.
Calculate the sum of the absolute value of the mean and the
absolute value of the confidence coefficient using equation 1-6,
and report this value as the 24-hour CD error.
(5) Retesting. If the COMS fails to meet the specifications for
the tests conducted under the operational test period, make the
necessary corrections and restart the operational test period.
Depending on the opinion of the enforcing agency, you may have to
repeat some or all of the field audit tests.
8.2 What are the responsibilities of the Opacity Monitor
Manufacturer?
You, the manufacturer, must carry out the following
activities:
(1) Conduct the verification procedures for design
specifications in section 6 of ASTM D6216-12.
(2) Conduct the verification procedures for performance
specifications in section 7 of ASTM D6216-12.
(3) Provide to the owner or operator, a report of the opacity
monitor's conformance to the design and performance specifications
required in sections 6 and 7 of ASTM D6216-12 in accordance with
the reporting requirements of section 9 in ASTM D6216-12.
9.0 What quality control measures are required by PS-1?
Opacity monitor manufacturers must initiate a quality program
following the requirements of ASTM D6216-12, section 8. The quality
program must include (1) a quality system and (2) a corrective
action program.
10.0 Calibration and Standardization [Reserved] 11.0 Analytical
Procedure [Reserved] 12.0 What Calculations Are Needed for PS-1?
12.1 Desired Attenuator Values. Calculate the desired attenuator
value corrected to the emission outlet pathlength as follows:
Where: OP1 = Nominal opacity value of required
low-, mid-, or high-range calibration attenuators. OP2 = Desired
attenuator opacity value from ASTM D6216-12, section 7.5 at the
opacity limit required by the applicable subpart. L1 = Monitoring
pathlength. L2 = Emission outlet pathlength.
12.2 Luminous Transmittance Value of a Filter. Calculate the
luminous transmittance of a filter as follows:
12.3 Arithmetic Mean. Calculate the arithmetic mean of a data
set as follows:
Where:
12.4 Standard Deviation. Calculate the standard deviation as
follows:
Where: Sd = Standard deviation of a data set.
12.5 Confidence Coefficient. Calculate the 2.5 percent error
confidence coefficient (one-tailed) as follows:
Where: CC = Confidence coefficient t0.975 = t −
value (see table 1-2).
12.6 Calibration Error. Calculate the error (calibration error,
zero drift error, and calibration drift error) as follows:
Where: Er = Error.
12.7 Conversion of Opacity Values for Monitor Pathlength to
Emission Outlet Pathlength. When the monitor pathlength is
different from the emission outlet pathlength, use either of the
following equations to convert from one basis to the other (this
conversion may be automatically calculated by the monitoring
system):
Where: Op1 = Opacity of the
effluent based upon L1. Op2 = Opacity of the effluent based upon
L2. L1 = Monitor pathlength. L2 = Emission outlet pathlength. OD1 =
Optical density of the effluent based upon L1. OD2 = Optical
density of the effluent based upon L2.
12.8 Mean Response Wavelength. Calculate the mean of the
effective spectral response curve from the individual responses at
the specified wavelength values as follows:
Where: L = mean of the effective spectral
response curve Li = The specified wavelength at which the response
gi is calculated at 20 nm intervals. gi = The individual response
value at Li. 13.0 What Specifications Does a COMS Have to Meet for
Certification?
A COMS must meet the following design, manufacturer's
performance, and field audit performance specifications:
Note: If the initial certification of the opacity monitor
occurred before November 14, 2018 using D6216-98, D6216-03, or
D6216-07, it is not necessary to recertify using D6216-12.A. COMS
must meet the following design, manufacturer's performance, and
field audit performance specifications.
13.1 Design Specifications. The opacity monitoring equipment
must comply with the design specifications of ASTM D6216-12.
13.2 Manufacturer's Performance Specifications. The opacity
monitor must comply with the manufacturer's performance
specifications of ASTM D6216-12.
13.3 Field Audit Performance Specifications. The installed COMS
must comply with the following performance specifications:
(1) Optical Alignment. Objectively indicate proper alignment
relative to reference marks (e.g., bull's-eye) or
conditions.
(2) Calibration Error. The calibration error must be ≤3 percent
opacity for each of the three calibration attenuators.
(3) System Response Time. The COMS upscale and downscale
response times must be ≤10 seconds as measured at the COMS data
recorder.
(4) Averaging Period Calculation and Recording. The COMS data
recorder must average and record each calibration attenuator value
to within ±2 percent opacity of the certified value of the
attenuator.
(5) Operational Test Period. The COMS must be able to measure
and record opacity and to perform daily calibration drift
assessments for 168 hours without unscheduled maintenance, repair,
or adjustment.
(6) Zero and Upscale Calibration Drift Error. The COMS zero and
upscale calibration drift error must not exceed 2 percent opacity
over a 24 hour period.
14.0 Pollution Prevention [Reserved] 15.0 Waste Management
[Reserved] 16.0 Which references are relevant to this method?
1. Experimental Statistics. Department of Commerce. National
Bureau of Standards Handbook 91. Paragraph 3-3.1.4. 1963. 3-31
p.
2. Performance Specifications for Stationary Source Monitoring
Systems for Gases and Visible Emissions, EPA-650/2-74-013, January
1974, U. S. Environmental Protection Agency, Research Triangle
Park, NC.
3. Koontz, E.C., Walton, J. Quality Assurance Programs for
Visible Emission Evaluations. Tennessee Division of Air Pollution
Control. Nashville, TN. 78th Meeting of the Air Pollution Control
Association. Detroit, MI. June 16-21, 1985.
4. Evaluation of Opacity CEMS Reliability and Quality Assurance
Procedures. Volume 1. U. S. Environmental Protection Agency.
Research Triangle Park, NC. EPA-340/1-86-009a.
5. Nimeroff, I. “Colorimetry Precision Measurement and
Calibration.” NBS Special Publication 300. Volume 9. June 1972.
6. Technical Assistance Document: Performance Audit Procedures
for Opacity Monitors. U. S. Environmental Protection Agency.
Research Triangle Park, NC. EPA-600/8-87-025. April 1987.
7. Technical Assistance Document: Performance Audit Procedures
for Opacity Monitors. U. S. Environmental Protection Agency.
Research Triangle Park, NC. EPA-450/4-92-010. April 1992.
8. ASTM D6216-12: Standard Practice for Opacity Monitor
Manufacturers to Certify Conformance with Design and Performance
Specifications. ASTM. October 2012.
17.0 What tables and diagrams are relevant to this method?
17.1 Reference Tables.
Table 1-1 - Source C, Human Eye Response
Factor
Wavelength
nanometers
Weighting
factor a
Wavelength
nanometers
Weighting
factor a
380
0
590
6627
390
0
600
5316
400
2
610
4176
410
9
620
3153
420
37
630
2190
430
122
640
1443
440
262
650
886
450
443
660
504
460
694
670
259
470
1058
680
134
480
1618
690
62
490
2358
700
29
500
3401
720
14
510
4833
720
6
520
6462
730
3
530
7934
740
2
540
9194
750
1
550
9832
760
1
560
9841
770
0
570
9147
780
0
580
7992
1 Total of weighting factors =
100,000.
Table 1-2 T Values
n a
t 0.975
n a
t 0.975
n a
t 0.975
2
12.706
7
2.447
12
2.201
3
4.303
8
2.365
13
2.179
4
3.182
9
2.306
14
2.160
5
2.776
10
2.262
15
2.145
6
2.571
11
2.228
16
2.131
a The values in this table are
already corrected for n-1 degrees of freedom. Use n equal to the
number of individual values.
17.2 Diagrams.
Performance
Specification 2 - Specifications and Test Procedures for SO2 and
NOX Continuous Emission Monitoring Systems in Stationary Sources
1.0 Scope and Application
1.1 Analytes
Analyte
CAS Nos.
Sulfur Dioxide
(SO2)
7449-09-5
Nitrogen Oxides
(NOX)
10102-44-0 (NO2), 10024-97-2
(NO)
1.2 Applicability.
1.2.1 This specification is for evaluating the acceptability of
SO2 and NOX continuous emission monitoring systems (CEMS) at the
time of installation or soon after and whenever specified in the
regulations. The CEMS may include, for certain stationary sources,
a diluent (O2 or CO2) monitor.
1.2.2 This specification is not designed to evaluate the
installed CEMS performance over an extended period of time nor does
it identify specific calibration techniques and other auxiliary
procedures to assess the CEMS performance. The source owner or
operator is responsible to calibrate, maintain, and operate the
CEMS properly. The Administrator may require, under section 114 of
the Act, the operator to conduct CEMS performance evaluations at
other times besides the initial test to evaluate the CEMS
performance. See 40 CFR Part 60, § 60.13(c).
2.0 Summary of Performance Specification
Procedures for measuring CEMS relative accuracy and calibration
drift are outlined. CEMS installation and measurement location
specifications, equipment specifications, performance
specifications, and data reduction procedures are included.
Conformance of the CEMS with the Performance Specification is
determined.
3.0 Definitions
3.1 Calibration Drift (CD) means the difference in the
CEMS output readings from the established reference value after a
stated period of operation during which no unscheduled maintenance,
repair, or adjustment took place.
3.2 Centroidal Area means a concentric area that is
geometrically similar to the stack or duct cross section and is no
greater than l percent of the stack or duct cross-sectional
area.
3.3 Continuous Emission Monitoring System means the total
equipment required for the determination of a gas concentration or
emission rate. The sample interface, pollutant analyzer, diluent
analyzer, and data recorder are the major subsystems of the
CEMS.
3.4 Data Recorder means that portion of the CEMS that
provides a permanent record of the analyzer output. The data
recorder may include automatic data reduction capabilities.
3.5 Diluent Analyzer means that portion of the CEMS that
senses the diluent gas (i.e., CO2 or O2) and generates an
output proportional to the gas concentration.
3.6 Path CEMS means a CEMS that measures the gas
concentration along a path greater than 10 percent of the
equivalent diameter of the stack or duct cross section.
3.7 Point CEMS means a CEMS that measures the gas
concentration either at a single point or along a path equal to or
less than 10 percent of the equivalent diameter of the stack or
duct cross section.
3.8 Pollutant Analyzer means that portion of the CEMS
that senses the pollutant gas and generates an output proportional
to the gas concentration.
3.9 Relative Accuracy (RA) means the absolute mean
difference between the gas concentration or emission rate
determined by the CEMS and the value determined by the reference
method (RM), plus the 2.5 percent error confidence coefficient of a
series of tests, divided by the mean of the RM tests or the
applicable emission limit.
3.10 Sample Interface means that portion of the CEMS used
for one or more of the following: sample acquisition, sample
delivery, sample conditioning, or protection of the monitor from
the effects of the stack effluent.
3.11 Span Value means the calibration portion of the
measurement range as specified in the applicable regulation or
other requirement. If the span is not specified in the applicable
regulation or other requirement, then it must be a value
approximately equivalent to two times the emission standard. For
spans less than 500 ppm, the span value may either be rounded
upward to the next highest multiple of 10 ppm, or to the next
highest multiple of 100 ppm such that the equivalent emission
concentration is not less than 30 percent of the selected span
value.
4.0 Interferences [Reserved] 5.0 Safety
The procedures required under this performance specification may
involve hazardous materials, operations, and equipment. This
performance specification may not address all of the safety
problems associated with these procedures. It is the responsibility
of the user to establish appropriate safety and health practices
and determine the applicable regulatory limitations prior to
performing these procedures. The CEMS user's manual and materials
recommended by the reference method should be consulted for
specific precautions to be taken.
6.0 Equipment and Supplies
6.1 CEMS Equipment Specifications.
6.1.1 Data Recorder. The portion of the CEMS that provides a
record of analyzer output. The data recorder may record other
pertinent data such as effluent flow rates, various instrument
temperatures or abnormal CEMS operation. The data recorder output
range must include the full range of expected concentration values
in the gas stream to be sampled including zero and span values.
6.1.2 The CEMS design should also allow the determination of
calibration drift at the zero and span values. If this is not
possible or practical, the design must allow these determinations
to be conducted at a low-level value (zero to 20 percent of the
span value) and at a value between 50 and 100 percent of the span
value. In special cases, the Administrator may approve a
single-point calibration drift determination.
6.2 Other equipment and supplies, as needed by the applicable
reference method(s) (see section 8.4.2 of this Performance
Specification), may be required.
7.0 Reagents and Standards
7.1 Reference Gases, Gas Cells, or Optical Filters. As specified
by the CEMS manufacturer for calibration of the CEMS (these need
not be certified).
7.2 Reagents and Standards. May be required as needed by the
applicable reference method(s) (see section 8.4.2 of this
Performance Specification).
8.0 Performance Specification Test Procedure
8.1 Installation and Measurement Location Specifications.
8.1.1 CEMS Installation. Install the CEMS at an accessible
location where the pollutant concentration or emission rate
measurements are directly representative or can be corrected so as
to be representative of the total emissions from the affected
facility or at the measurement location cross section. Then select
representative measurement points or paths for monitoring in
locations that the CEMS will pass the RA test (see section 8.4). If
the cause of failure to meet the RA test is determined to be the
measurement location and a satisfactory correction technique cannot
be established, the Administrator may require the CEMS to be
relocated. Suggested measurement locations and points or paths that
are most likely to provide data that will meet the RA requirements
are listed below.
8.1.2 CEMS Measurement Location. It is suggested that the
measurement location be (1) at least two equivalent diameters
downstream from the nearest control device, the point of pollutant
generation, or other point at which a change in the pollutant
concentration or emission rate may occur and (2) at least a half
equivalent diameter upstream from the effluent exhaust or control
device.
8.1.2.1 Point CEMS. It is suggested that the measurement point
be (1) no less than 1.0 meter (3.3 ft) from the stack or duct wall
or (2) within or centrally located over the centroidal area of the
stack or duct cross section.
8.1.2.2 Path CEMS. It is suggested that the effective
measurement path (1) be totally within the inner area bounded by a
line 1.0 meter (3.3 ft) from the stack or duct wall, or (2) have at
least 70 percent of the path within the inner 50 percent of the
stack or duct cross-sectional area, or (3) be centrally located
over any part of the centroidal area.
8.1.3 Reference Method Measurement Location and Traverse
Points.
8.1.3.1 Select, as appropriate, an accessible RM measurement
point at least two equivalent diameters downstream from the nearest
control device, the point of pollutant generation, or other point
at which a change in the pollutant concentration or emission rate
may occur, and at least a half equivalent diameter upstream from
the effluent exhaust or control device. When pollutant
concentration changes are due solely to diluent leakage
(e.g., air heater leakages) and pollutants and diluents are
simultaneously measured at the same location, a half diameter may
be used in lieu of two equivalent diameters. The CEMS and RM
locations need not be the same.
8.1.3.2 Select traverse points that assure acquisition of
representative samples over the stack or duct cross section. The
minimum requirements are as follows: Establish a “measurement line”
that passes through the centroidal area and in the direction of any
expected stratification. If this line interferes with the CEMS
measurements, displace the line up to 30 cm (12 in.) (or 5 percent
of the equivalent diameter of the cross section, whichever is less)
from the centroidal area. Locate three traverse points at 16.7,
50.0, and 83.3 percent of the measurement line. If the measurement
line is longer than 2.4 meters (7.8 ft) and pollutant
stratification is not expected, the three traverse points may be
located on the line at 0.4, 1.2, and 2.0 meters from the stack or
duct wall. This option must not be used after wet scrubbers or at
points where two streams with different pollutant concentrations
are combined. If stratification is suspected, the following
procedure is suggested. For rectangular ducts, locate at least nine
sample points in the cross section such that sample points are the
centroids of similarly-shaped, equal area divisions of the cross
section. Measure the pollutant concentration, and, if applicable,
the diluent concentration at each point using appropriate reference
methods or other appropriate instrument methods that give responses
relative to pollutant concentrations. Then calculate the mean value
for all sample points. For circular ducts, conduct a 12-point
traverse (i.e., six points on each of the two perpendicular
diameters) locating the sample points as described in 40 CFR 60,
Appendix A, Method 1. Perform the measurements and calculations as
described above. Determine if the mean pollutant concentration is
more than 10% different from any single point. If so, the cross
section is considered to be stratified, and the tester may not use
the alternative traverse point locations (...0.4, 1.2, and 2.0
meters from the stack or duct wall.) but must use the three
traverse points at 16.7, 50.0, and 83.3 percent of the entire
measurement line. Other traverse points may be selected, provided
that they can be shown to the satisfaction of the Administrator to
provide a representative sample over the stack or duct cross
section. Conduct all necessary RM tests within 3 cm (1.2 in.) of
the traverse points, but no closer than 3 cm (1.2 in.) to the stack
or duct wall.
8.2 Pretest Preparation. Install the CEMS, prepare the RM test
site according to the specifications in section 8.1, and prepare
the CEMS for operation according to the manufacturer's written
instructions.
8.3 Calibration Drift Test Procedure.
8.3.1 CD Test Period. While the affected facility is
operating, determine the magnitude of the CD once each day (at
24-hour intervals) for 7 consecutive calendar days according to the
procedure given in sections 8.3.2 through 8.3.4. Alternatively, the
CD test may be conducted over 7 consecutive unit operating
days.
8.3.2 The purpose of the CD measurement is to verify the ability
of the CEMS to conform to the established CEMS calibration used for
determining the emission concentration or emission rate. Therefore,
if periodic automatic or manual adjustments are made to the CEMS
zero and calibration settings, conduct the CD test immediately
before these adjustments, or conduct it in such a way that the CD
can be determined.
8.3.3 Conduct the CD test at the two points specified in section
6.1.2. Introduce to the CEMS the reference gases, gas cells, or
optical filters (these need not be certified). Record the CEMS
response and subtract this value from the reference value (see
example data sheet in Figure 2-1).
8.4 Relative Accuracy Test Procedure.
8.4.1 RA Test Period. Conduct the RA test according to the
procedure given in sections 8.4.2 through 8.4.6 while the affected
facility is operating at more than 50 percent of normal load, or as
specified in an applicable subpart. The RA test may be conducted
during the CD test period.
8.4.2 Reference Methods. Unless otherwise specified in an
applicable subpart of the regulations, Methods 3B, 4, 6, and 7, or
their approved alternatives, are the reference methods for diluent
(O2 and CO2), moisture, SO2, and NOX, respectively.
8.4.3 Sampling Strategy for RM Tests. Conduct the RM tests in
such a way that they will yield results representative of the
emissions from the source and can be correlated to the CEMS data.
It is preferable to conduct the diluent (if applicable), moisture
(if needed), and pollutant measurements simultaneously. However,
diluent and moisture measurements that are taken within an hour of
the pollutant measurements may be used to calculate dry pollutant
concentration and emission rates. In order to correlate the CEMS
and RM data properly, note the beginning and end of each RM test
period of each run (including the exact time of day) on the CEMS
chart recordings or other permanent record of output. Use the
following strategies for the RM tests:
8.4.3.1 For integrated samples (e.g., Methods 6 and
Method 4), make a sample traverse of at least 21 minutes, sampling
for an equal time at each traverse point (see section 8.1.3.2 for
discussion of traverse points.
8.4.3.2 For grab samples (e.g., Method 7), take one
sample at each traverse point, scheduling the grab samples so that
they are taken simultaneously (within a 3-minute period) or at an
equal interval of time apart over the span of time the CEM
pollutant is measured. A test run for grab samples must be made up
of at least three separate measurements.
Note:
At times, CEMS RA tests are conducted during new source
performance standards performance tests. In these cases, RM results
obtained during CEMS RA tests may be used to determine compliance
as long as the source and test conditions are consistent with the
applicable regulations.
8.4.4 Number of RM Tests. Conduct a minimum of nine sets of all
necessary RM test runs.
Note:
More than nine sets of RM tests may be performed. If this option
is chosen, a maximum of three sets of the test results may be
rejected so long as the total number of test results used to
determine the RA is greater than or equal to nine. However, all
data must be reported, including the rejected data.
8.4.5 Correlation of RM and CEMS Data. Correlate the CEMS and
the RM test data as to the time and duration by first determining
from the CEMS final output (the one used for reporting) the
integrated average pollutant concentration or emission rate for
each pollutant RM test period. Consider system response time, if
important, and confirm that the pair of results are on a consistent
moisture, temperature, and diluent concentration basis. Then,
compare each integrated CEMS value against the corresponding
average RM value. Use the following guidelines to make these
comparisons.
8.4.5.1 If the RM has an integrated sampling technique, make a
direct comparison of the RM results and CEMS integrated average
value.
8.4.5.2 If the RM has a grab sampling technique, first average
the results from all grab samples taken during the test run, and
then compare this average value against the integrated value
obtained from the CEMS chart recording or output during the run. If
the pollutant concentration is varying with time over the run, the
arithmetic average of the CEMS value recorded at the time of each
grab sample may be used.
8.4.6 Calculate the mean difference between the RM and CEMS
values in the units of the emission standard, the standard
deviation, the confidence coefficient, and the relative accuracy
according to the procedures in section 12.0.
8.5 Reporting. At a minimum (check with the appropriate regional
office, State, or Local agency for additional requirements, if
any), summarize in tabular form the results of the CD tests and the
RA tests or alternative RA procedure, as appropriate. Include all
data sheets, calculations, charts (records of CEMS responses),
cylinder gas concentration certifications, and calibration cell
response certifications (if applicable) necessary to confirm that
the performance of the CEMS met the performance specifications.
9.0 Quality Control [Reserved] 10.0 Calibration and Standardization
[Reserved] 11.0 Analytical Procedure
Sample collection and analysis are concurrent for this
Performance Specification (see section 8.0). Refer to the RM for
specific analytical procedures.
12.0 Calculations and Data Analysis
Summarize the results on a data sheet similar to that shown in
Figure 2-2 (in section 18.0).
12.1 All data from the RM and CEMS must be on a consistent dry
basis and, as applicable, on a consistent diluent basis and in the
units of the emission standard. Correct the RM and CEMS data for
moisture and diluent as follows:
12.1.1 Moisture Correction (as applicable). Correct each wet RM
run for moisture with the corresponding Method 4 data; correct each
wet CEMS run using the corresponding CEMS moisture monitor date
using Equation 2-1.
12.1.2 Correction to Units of Standard (as applicable). Correct
each dry RM run to the units of the emission standard with the
corresponding Method 3B data; correct each dry CEMS run using the
corresponding CEMS diluent monitor data as follows:
12.1.2.1 Correct to Diluent Basis. The following is an example
of concentration (ppm) correction to 7% oxygen.
The following is an example of mass/gross calorific value
(lbs/million Btu) correction.
lbs/MMBtu = Conc(dry) (F-factor) (20.9/20.9-%02)
12.2 Arithmetic Mean. Calculate the arithmetic mean of the
difference, d, of a data set as follows:
Where: n = Number of data points.
12.3 Standard Deviation. Calculate the standard deviation, Sd,
as follows:
12.4 Confidence Coefficient. Calculate the 2.5 percent error
confidence coefficient (one-tailed), CC, as follows:
Where: t 0.975 = t-value (see Table 2-1).
12.5 Relative Accuracy. Calculate the RA of a set of data as
follows:
Where: |d | = Absolute value of the mean
differences (from Equation 2-3). |CC| = Absolute value of the
confidence coefficient (from Equation 2-3). RM = Average RM value.
In cases where the average emissions for the test are less than 50
percent of the applicable standard, substitute the emission
standard value in the denominator of Eq. 2-6 in place of RM. In all
other cases, use RM. 13.0 Method Performance
13.1 Calibration Drift Performance Specification. The CEMS
calibration must not drift or deviate from the reference value of
the gas cylinder, gas cell, or optical filter by more than 2.5
percent of the span value. If the CEMS includes pollutant and
diluent monitors, the CD must be determined separately for each in
terms of concentrations (See Performance Specification 3 for the
diluent specifications), and none of the CDs may exceed the
specification.
13.2 Relative Accuracy Performance Specification.
Calculate . . .
RA criteria
(%)
If average
emissions during the RATA are ≥50% of emission standard
Use Eq. 2-6, with RM in the
denominator
≤20.0
If average
emissions during the RATA are <50% of emission standard
Use Eq. 2-6, emission standard
in the denominator
≤10.0
For SO2 emission
standards ≤130 but ≥86 ng/J (0.30 and 0.20 lb/million Btu)
Use Eq. 2-6, emission standard
in the denominator
≤15.0
For SO2 emission
standards <86 ng/J (0.20 lb/million Btu)
Use Eq. 2-6, emission standard
in the denominator
≤20.0
13.3 For instruments that use common components to measure more
than one effluent gas constituent, all channels must simultaneously
pass the RA requirement, unless it can be demonstrated that any
adjustments made to one channel did not affect the others.
Paragraphs 60.13(j)(1) and (2) of 40 CFR part 60 contain
criteria for which the reference method procedure for determining
relative accuracy (see section 8.4 of this Performance
Specification) may be waived and the following procedure
substituted.
16.1 Conduct a complete CEMS status check following the
manufacturer's written instructions. The check should include
operation of the light source, signal receiver, timing mechanism
functions, data acquisition and data reduction functions, data
recorders, mechanically operated functions (mirror movements, zero
pipe operation, calibration gas valve operations, etc.), sample
filters, sample line heaters, moisture traps, and other related
functions of the CEMS, as applicable. All parts of the CEMS shall
be functioning properly before proceeding to the alternative RA
procedure.
16.2 Alternative RA Procedure.
16.2.1 Challenge each monitor (both pollutant and diluent, if
applicable) with cylinder gases of known concentrations or
calibration cells that produce known responses at two measurement
points within the ranges shown in Table 2-2 (Section 18).
16.2.2 Use a separate cylinder gas (for point CEMS only) or
calibration cell (for path CEMS or where compressed gas cylinders
can not be used) for measurement points 1 and 2. Challenge the CEMS
and record the responses three times at each measurement point. The
Administrator may allow dilution of cylinder gas using the
performance criteria in Test Method 205, 40 CFR Part 51, Appendix
M. Use the average of the three responses in determining relative
accuracy.
16.2.3 Operate each monitor in its normal sampling mode as
nearly as possible. When using cylinder gases, pass the cylinder
gas through all filters, scrubbers, conditioners, and other monitor
components used during normal sampling and as much of the sampling
probe as practical. When using calibration cells, the CEMS
components used in the normal sampling mode should not be by-passed
during the RA determination. These include light sources, lenses,
detectors, and reference cells. The CEMS should be challenged at
each measurement point for a sufficient period of time to assure
adsorption-desorption reactions on the CEMS surfaces have
stabilized.
16.2.4 Use cylinder gases that have been certified by comparison
to National Institute of Standards and Technology (NIST) gaseous
standard reference material (SRM) or NIST/EPA approved gas
manufacturer's certified reference material (CRM) (See Reference 2
in section 17.0) following EPA Traceability Protocol Number 1 (See
Reference 3 in section 17.0). As an alternative to Protocol Number
1 gases, CRM's may be used directly as alternative RA cylinder
gases. A list of gas manufacturers that have prepared approved
CRM's is available from EPA at the address shown in Reference 2.
Procedures for preparation of CRM's are described in Reference
2.
16.2.5 Use calibration cells certified by the manufacturer to
produce a known response in the CEMS. The cell certification
procedure shall include determination of CEMS response produced by
the calibration cell in direct comparison with measurement of gases
of known concentration. This can be accomplished using SRM or CRM
gases in a laboratory source simulator or through extended tests
using reference methods at the CEMS location in the exhaust stack.
These procedures are discussed in Reference 4 in section 17.0. The
calibration cell certification procedure is subject to approval of
the Administrator.
16.3 The differences between the known concentrations of the
cylinder gases and the concentrations indicated by the CEMS are
used to assess the accuracy of the CEMS. The calculations and
limits of acceptable relative accuracy are as follows:
16.3.1 For pollutant CEMS:
Where: d = Average difference between responses
and the concentration/responses (see section 16.2.2). AC = The
known concentration/response of the cylinder gas or calibration
cell.
16.3.2 For diluent CEMS:
RA= d; ≤0.7 percent O2 or CO2, as applicable. Note:
Waiver of the relative accuracy test in favor of the alternative
RA procedure does not preclude the requirements to complete the CD
tests nor any other requirements specified in an applicable subpart
for reporting CEMS data and performing CEMS drift checks or
audits.
17.0 References
1. Department of Commerce. Experimental Statistics. Handbook 91.
Washington, D.C. p. 3-31, paragraphs 3-3.1.4.
2. “A Procedure for Establishing Traceability of Gas Mixtures to
Certain National Bureau of Standards Standard Reference Materials.”
Joint publication by NBS and EPA. EPA 600/7-81-010. Available from
U.S. Environmental Protection Agency, Quality Assurance Division
(MD-77), Research Triangle Park, North Carolina 27711.
3. “Traceability Protocol for Establishing True Concentrations
of Gases Used for Calibration and Audits of Continuous Source
Emission Monitors. (Protocol Number 1).” June 1978. Protocol Number
1 is included in the Quality Assurance Handbook for Air Pollution
Measurement Systems, Volume III, Stationary Source Specific
Methods. EPA-600/4-77-027b. August 1977.
4. “Gaseous Continuous Emission Monitoring Systems - Performance
Specification Guidelines for SO2, NOX, CO2, O2, and TRS.”
EPA-450/3-82-026. Available from the U.S. EPA, Emission Measurement
Center, Emission Monitoring and Data Analysis Division (MD-19),
Research Triangle Park, North Carolina 27711.
18.0 Tables, Diagrams, Flowcharts, and Validation Data
Table 2-1 - t-Values
n a
t0.975
n a
t0.975
n a
t0.975
2
12.706
7
2.447
12
2.201
3
4.303
8
2.365
13
2.179
4
3.182
9
2.306
14
2.160
5
2.776
10
2.262
15
2.145
6
2.571
11
2.228
16
2.131
a The values in this table are
already corrected for n−1 degrees of freedom. Use n equal to the
number of individual values.
Table 2-2 - Measurement Range
Measurement
point
Pollutant
monitor
Diluent monitor
for
CO2
O2
1
20-30% of span value
5-8% by volume
4-6% by volume.
2
50-60% of span value
10-14% by volume
8-12% by volume.
a For Steam generators.
b Average of three samples.
c Make sure that RM and CEMS data
are on a consistent basis, either wet or dry.
Performance Specification 3 - Specifications and Test Procedures
for O2 and CO2 Continuous Emission Monitoring Systems in Stationary
Sources 1.0 Scope and Application
1.1 Analytes.
Analytes
CAS No.
Carbon Dioxide
(CO2)
124-38-9
Oxygen (O2)
7782-44-7
1.2 Applicability.
1.2.1 This specification is for evaluating acceptability of O2
and CO2 continuous emission monitoring systems (CEMS) at the time
of installation or soon after and whenever specified in an
applicable subpart of the regulations. This specification applies
to O2 or CO2 monitors that are not included under Performance
Specification 2 (PS 2).
1.2.2 This specification is not designed to evaluate the
installed CEMS performance over an extended period of time, nor
does it identify specific calibration techniques and other
auxiliary procedures to assess the CEMS performance. The source
owner or operator, is responsible to calibrate, maintain, and
operate the CEMS properly. The Administrator may require, under
section 114 of the Act, the operator to conduct CEMS performance
evaluations at other times besides the initial test to evaluate the
CEMS performance. See 40 CFR part 60, section 60.13(c).
1.2.3 The definitions, installation and measurement location
specifications, calculations and data analysis, and references are
the same as in PS 2, sections 3, 8.1, 12, and 17, respectively, and
also apply to O2 and CO2 CEMS under this specification. The
performance and equipment specifications and the relative accuracy
(RA) test procedures for O2 and CO2 CEMS do not differ from those
for SO2 and NOX CEMS (see PS 2), except as noted below.
2.0 Summary of Performance Specification
The RA and calibration drift (CD) tests are conducted to
determine conformance of the CEMS to the specification.
3.0 Definitions
Same as in section 3.0 of PS 2.
4.0 Interferences [Reserved] 5.0 Safety
This performance specification may involve hazardous materials,
operations, and equipment. This performance specification may not
address all of the safety problems associated with its use. It is
the responsibility of the user to establish appropriate safety and
health practices and determine the applicable regulatory
limitations prior to performing this performance specification. The
CEMS users manual should be consulted for specific precautions to
be taken with regard to the analytical procedures.
6.0 Equipment and Supplies
Same as section 6.0 of PS2.
7.0 Reagents and Standards
Same as section 7.0 of PS2.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Relative Accuracy Test Procedure. Sampling Strategy for
reference method (RM) Tests, Correlation of RM and CEMS Data, and
Number of RM Tests. Same as PS 2, sections 8.4.3, 8.4.5, and 8.4.4,
respectively.
8.2 Reference Method. Unless otherwise specified in an
applicable subpart of the regulations, Method 3B or other approved
alternative is the RM for O2 or CO2.
9.0 Quality Control [Reserved] 10.0 Calibration and Standardization
[Reserved] 11.0 Analytical Procedure
Sample collection and analyses are concurrent for this
performance specification (see section 8). Refer to the RM for
specific analytical procedures.
12.0 Calculations and Data Analysis
Calculate the RA using equations 3-1 and 3-2. Summarize the
results on a data sheet similar to that shown in Figure 2.2 of
PS2.
13.0 Method
Performance
13.1 Calibration Drift Performance Specification. The CEMS
calibration must not drift by more than 0.5 percent O2 or CO2 from
the reference value of the gas, gas cell, or optical filter.
13.2 CEMS Relative Accuracy Performance Specification. The RA of
the CEMS must be no greater than 20.0 percent of the mean value of
the reference method (RM) data when calculated using equation 3-1.
The results are also acceptable if the result of Equation 3-2 is
less than or equal to 1.0 percent O2 (or CO2).
17.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
Performance Specification 4 - Specifications and Test Procedures
for Carbon Monoxide Continuous Emission Monitoring Systems in
Stationary Sources 1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Carbon Monoxide
(CO)
630-08-0
1.2 Applicability.
1.2.1 This specification is for evaluating the acceptability of
carbon monoxide (CO) continuous emission monitoring systems (CEMS)
at the time of installation or soon after and whenever specified in
an applicable subpart of the regulations. This specification was
developed primarily for CEMS having span values of 1,000 ppmv
CO.
1.2.2 This specification is not designed to evaluate the
installed CEMS performance over an extended period of time nor does
it identify specific calibration techniques and other auxiliary
procedures to assess CEMS performance. The source owner or
operator, is responsible to calibrate, maintain, and operate the
CEMS. The Administrator may require, under section 114 of the Act,
the source owner or operator to conduct CEMS performance
evaluations at other times besides the initial test to evaluate the
CEMS performance. See 40 CFR part 60, section 60.13(c).
1.2.3 The definitions, performance specification test
procedures, calculations, and data analysis procedures for
determining calibration drift (CD) and relative accuracy (RA) of
Performance Specification 2 (PS 2), sections 3, 8.0, and 12,
respectively, apply to this specification.
2.0 Summary of Performance Specification
The CD and RA tests are conducted to determine conformance of
the CEMS to the specification.
3.0 Definitions
Same as in section 3.0 of PS 2.
4.0 Interferences [Reserved] 5.0 Safety
This performance specification may involve hazardous materials,
operations, and equipment. This performance specification may not
address all of the safety problems associated with its use. It is
the responsibility of the user to establish appropriate safety and
health practices and determine the applicable regulatory
limitations prior to performing this performance specification. The
CEMS users manual should be consulted for specific precautions to
be taken with regard to the analytical procedures.
6.0 Equipment and Supplies
Same as section 6.0 of PS 2.
7.0 Reagents and Standards
Same as section 7.0 of PS 2.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Relative Accuracy Test Procedure. Sampling Strategy for
reference method (RM) Tests, Number of RM Tests, and Correlation of
RM and CEMS Data are the same as PS 2, sections 8.4.3, 8.4.4, and
8.4.5, respectively.
8.2 Reference Methods. Unless otherwise specified in an
applicable subpart of the regulation, Method 10, 10A, 10B or other
approved alternative are the RM for this PS.
9.0 Quality Control [Reserved] 10.0 Calibration and Standardization
[Reserved] 11.0 Analytical Procedure
Sample collection and analysis are concurrent for this
performance specification (see section 8.0). Refer to the RM for
specific analytical procedures.
12.0 Calculations and Data Analysis
Same as section 12.0 of PS 2.
13.0 Method Performance
13.1 Calibration Drift. The CEMS calibration must not drift or
deviate from the reference value of the calibration gas, gas cell,
or optical filter by more than 5 percent of the established span
value for 6 out of 7 test days (e.g., the established span
value is 1000 ppm for Subpart J affected facilities).
13.2 Relative Accuracy. The RA of the CEMS must be no greater
than 10 percent when the average RM value is used to calculate RA
or 5 percent when the applicable emission standard is used to
calculate RA.
1. Ferguson, B.B., R.E. Lester, and W.J. Mitchell. Field
Evaluation of Carbon Monoxide and Hydrogen Sulfide Continuous
Emission Monitors at an Oil Refinery. U.S. Environmental Protection
Agency. Research Triangle Park, N.C. Publication No.
EPA-600/4-82-054. August 1982. 100 p.
2. “Gaseous Continuous Emission Monitoring Systems - Performance
Specification Guidelines for SO2, NOX, CO2, O2, and TRS.”
EPA-450/3-82-026. U.S. Environmental Protection Agency, Technical
Support Division (MD-19), Research Triangle Park, NC 27711.
3. Repp, M. Evaluation of Continuous Monitors for Carbon
Monoxide in Stationary Sources. U.S. Environmental Protection
Agency. Research Triangle Park, N.C. Publication No.
EPA-600/2-77-063. March 1977. 155 p.
4. Smith, F., D.E. Wagoner, and R.P. Donovan. Guidelines for
Development of a Quality Assurance Program: Volume VIII -
Determination of CO Emissions from Stationary Sources by NDIR
Spectrometry. U.S. Environmental Protection Agency. Research
Triangle Park, N.C. Publication No. EPA-650/4-74-005-h. February
1975. 96 p.
18.0 Tables, Diagrams, Flowcharts, and Validation Data
Same as section 18.0 of PS 2.
Performance Specification 4A - Specifications and Test Procedures
for Carbon Monoxide Continuous Emission Monitoring Systems in
Stationary Sources 1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Carbon Monoxide
(CO)
630-80-0
1.2 Applicability.
1.2.1 This specification is for evaluating the acceptability of
carbon monoxide (CO) continuous emission monitoring systems (CEMS)
at the time of installation or soon after and whenever specified in
an applicable subpart of the regulations. This specification was
developed primarily for CEMS that comply with low emission
standards (less than 200 ppmv).
1.2.2 This specification is not designed to evaluate the
installed CEMS performance over an extended period of time nor does
it identify specific calibration techniques and other auxiliary
procedures to assess CEMS performance. The source owner or operator
is responsible to calibrate, maintain, and operate the CEMS. The
Administrator may require, under section 114 of the Act, the source
owner or operator to conduct CEMS performance evaluations at other
times besides the initial test to evaluate CEMS performance. See 40
CFR Part 60, section 60.13(c).
1.2.3 The definitions, performance specification, test
procedures, calculations and data analysis procedures for
determining calibration drifts (CD) and relative accuracy (RA), of
Performance Specification 2 (PS 2), sections 3, 8.0, and 12,
respectively, apply to this specification.
2.0 Summary of Performance Specification
The CD and RA tests are conducted to determine conformance of
the CEMS to the specification.
3.0 Definitions
Same as in section 3.0 of PS 2.
4.0 Interferences [Reserved] 5.0 Safety
This performance specification may involve hazardous materials,
operations, and equipment. This performance specification may not
address all of the safety problems associated with its use. It is
the responsibility of the user to establish appropriate safety and
health practices and determine the applicable regulatory
limitations prior to performing this performance specification. The
CEMS users manual should be consulted for specific precautions to
be taken with regard to the analytical procedures.
6.0 Equipment and Supplies
Same as section 6.0 of PS 2 with the following additions.
6.1 Data Recorder Scale.
6.1.1 This specification is the same as section 6.1 of PS 2. The
CEMS shall be capable of measuring emission levels under normal
conditions and under periods of short-duration peaks of high
concentrations. This dual-range capability may be met using two
separate analyzers (one for each range) or by using dual-range
units which have the capability of measuring both levels with a
single unit. In the latter case, when the reading goes above the
full-scale measurement value of the lower range, the higher-range
operation shall be started automatically. The CEMS recorder range
must include zero and a high-level value. Under applications of
consistent low emissions, a single-range analyzer is allowed
provided normal and spike emissions can be quantified. In this
case, set an appropriate high-level value to include all
emissions.
6.1.2 For the low-range scale of dual-range units, the
high-level value shall be between 1.5 times the pollutant
concentration corresponding to the emission standard level and the
span value. For the high-range scale, the high-level value shall be
set at 2000 ppm, as a minimum, and the range shall include the
level of the span value. There shall be no concentration gap
between the low-and high-range scales.
7.0 Reagents and Standards
Same as section 7.0 of PS 2.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Relative Accuracy Test Procedure. Sampling Strategy for
reference method (RM) Tests, Number of RM Tests, and Correlation of
RM and CEMS Data are the same as PS 2, sections 8.4.3, 8.4.4, and
8.4.5, respectively.
8.2 Reference Methods. Unless otherwise specified in an
applicable subpart of the regulation, Methods 10, 10A, 10B, or
other approved alternative is the RM for this PS. When evaluating
nondispersive infrared CEMS using Method 10 as the RM, the
alternative interference trap specified in section 16.0 of Method
10 shall be used.
8.3 Response Time Test Procedure. The response time test applies
to all types of CEMS, but will generally have significance only for
extractive systems. The entire system is checked with this
procedure including applicable sample extraction and transport,
sample conditioning, gas analyses, and data recording.
8.3.1 Introduce zero gas into the system. When the system output
has stabilized (no change greater than 1 percent of full scale for
30 sec), introduce an upscale calibration gas and wait for a stable
value. Record the time (upscale response time) required to reach 95
percent of the final stable value. Next, reintroduce the zero gas
and wait for a stable reading before recording the response time
(downscale response time). Repeat the entire procedure until you
have three sets of data to determine the mean upscale and downscale
response times. The slower or longer of the two means is the system
response time.
8.4 Interference Check. The CEMS must be shown to be free from
the effects of any interferences.
9.0 Quality Control [Reserved] 10.0 Calibration and Standardization
[Reserved] 11.0 Analytical Procedure
Sample collection and analysis are concurrent for this
performance specification (see section 8.0). Refer to the RM for
specific analytical procedures.
12.0 Calculations and Data Analysis. Same as section 12.0 of PS 2
13.0 Method Performance
13.1 Calibration Drift. The CEMS calibration must not drift or
deviate from the reference value of the calibration gas, gas cell,
or optical filter by more than 5 percent of the established span
value for 6 out of 7 test days.
13.2 Relative Accuracy. The RA of the CEMS must be no greater
than 10 percent when the average RM value is used to calculate RA,
5 percent when the applicable emission standard is used to
calculate RA, or within 5 ppmv when the RA is calculated as the
absolute average difference between the RM and CEMS plus the 2.5
percent confidence coefficient.
13.3 Response Time. The CEMS response time shall not exceed 240
seconds to achieve 95 percent of the final stable value.
16.1 Under conditions where the average CO emissions are less
than 10 percent of the standard and this is verified by Method 10,
a cylinder gas audit may be performed in place of the RA test to
determine compliance with these limits. In this case, the cylinder
gas shall contain CO in 12 percent carbon dioxide as an
interference check. If this option is exercised, Method 10 must be
used to verify that emission levels are less than 10 percent of the
standard.
17.0 References
Same as section 17 of PS 4.
18.0 Tables, Diagrams, Flowcharts, and Validation Data
Same as section 18.0 of PS 2.
Performance Specification 4B - Specifications and Test Procedures
for Carbon Monoxide and Oxygen Continuous Monitoring Systems in
Stationary Sources a. Applicability and Principle
1.1 Applicability. a. This specification is to be used for
evaluating the acceptability of carbon monoxide (CO) and oxygen
(O2) continuous emission monitoring systems (CEMS) at the time of
or soon after installation and whenever specified in the
regulations. The CEMS may include, for certain stationary sources,
(a) flow monitoring equipment to allow measurement of the dry
volume of stack effluent sampled, and (b) an automatic sampling
system.
b. This specification is not designed to evaluate the installed
CEMS' performance over an extended period of time nor does it
identify specific calibration techniques and auxiliary procedures
to assess the CEMS' performance. The source owner or operator,
however, is responsible to properly calibrate, maintain, and
operate the CEMS. To evaluate the CEMS' performance, the
Administrator may require, under section 114 of the Act, the
operator to conduct CEMS performance evaluations at times other
than the initial test.
c. The definitions, installation and measurement location
specifications, test procedures, data reduction procedures,
reporting requirements, and bibliography are the same as in PS 3
(for O2) and PS 4A (for CO) except as otherwise noted below.
1.2 Principle. Installation and measurement location
specifications, performance specifications, test procedures, and
data reduction procedures are included in this specification.
Reference method tests, calibration error tests, calibration drift
tests, and interferant tests are conducted to determine conformance
of the CEMS with the specification.
b. Definitions
2.1 Continuous Emission Monitoring System (CEMS). This
definition is the same as PS 2 section 2.1 with the following
addition. A continuous monitor is one in which the sample to be
analyzed passes the measurement section of the analyzer without
interruption.
2.2 Response Time. The time interval between the start of
a step change in the system input and when the pollutant analyzer
output reaches 95 percent of the final value.
2.3 Calibration Error (CE). The difference between the
concentration indicated by the CEMS and the known concentration
generated by a calibration source when the entire CEMS, including
the sampling interface is challenged. A CE test procedure is
performed to document the accuracy and linearity of the CEMS over
the entire measurement range.
3. Installation and Measurement Location Specifications
3.1 The CEMS Installation and Measurement Location. This
specification is the same as PS 2 section 3.1 with the following
additions. Both the CO and O2 monitors should be installed at the
same general location. If this is not possible, they may be
installed at different locations if the effluent gases at both
sample locations are not stratified and there is no in-leakage of
air between sampling locations.
3.1.1 Measurement Location. Same as PS 2 section
3.1.1.
3.1.2 Point CEMS. The measurement point should be within
or centrally located over the centroidal area of the stack or duct
cross section.
3.1.3 Path CEMS. The effective measurement path should:
(1) Have at least 70 percent of the path within the inner 50
percent of the stack or duct cross sectional area, or (2) be
centrally located over any part of the centroidal area.
3.2 Reference Method (RM) Measurement Location and Traverse
Points. This specification is the same as PS 2 section 3.2 with
the following additions. When pollutant concentration changes are
due solely to diluent leakage and CO and O2 are simultaneously
measured at the same location, one half diameter may be used in
place of two equivalent diameters.
3.3 Stratification Test Procedure. Stratification is
defined as the difference in excess of 10 percent between the
average concentration in the duct or stack and the concentration at
any point more than 1.0 meter from the duct or stack wall. To
determine whether effluent stratification exists, a dual probe
system should be used to determine the average effluent
concentration while measurements at each traverse point are being
made. One probe, located at the stack or duct centroid, is used as
a stationary reference point to indicate change in the effluent
concentration over time. The second probe is used for sampling at
the traverse points specified in Method 1 (40 CFR part 60 appendix
A). The monitoring system samples sequentially at the reference and
traverse points throughout the testing period for five minutes at
each point.
d. Performance and Equipment Specifications
4.1 Data Recorder Scale. For O2, same as specified in PS 3,
except that the span must be 25 percent. The span of the O2 may be
higher if the O2 concentration at the sampling point can be greater
than 25 percent. For CO, same as specified in PS 4A, except that
the low-range span must be 200 ppm and the high range span must be
3000 ppm. In addition, the scale for both CEMS must record all
readings within a measurement range with a resolution of 0.5
percent.
4.2 Calibration Drift. For O2, same as specified in PS 3.
For CO, the same as specified in PS 4A except that the CEMS
calibration must not drift from the reference value of the
calibration standard by more than 3 percent of the span value on
either the high or low range.
4.3 Relative Accuracy (RA). For O2, same as specified in
PS 3. For CO, the same as specified in PS 4A.
4.4 Calibration Error (CE). The mean difference between
the CEMS and reference values at all three test points (see Table
I) must be no greater than 5 percent of span value for CO monitors
and 0.5 percent for O2 monitors.
4.5 Response Time. The response time for the CO or O2
monitor must not exceed 240 seconds.
e. Performance Specification Test Procedure
5.1 Calibration Error Test and Response Time Test
Periods. Conduct the CE and response time tests during the CD
test period.
F. The CEMS Calibration Drift and Response Time Test Procedures
The response time test procedure is given in PS 4A, and must be
carried out for both the CO and O2 monitors.
7. Relative Accuracy and Calibration Error Test Procedures
7.1 Calibration Error Test Procedure. Challenge each
monitor (both low and high range CO and O2) with zero gas and EPA
Protocol 1 cylinder gases at three measurement points within the
ranges specified in Table I.
Table I. Calibration Error Concentration
Ranges
Measurement point
CO Low range (ppm)
CO High range (ppm)
O2 (%)
1
0-40
0-600
0-2
2
60-80
900-1200
8-10
3
140-160
2100-2400
14-16
Operate each monitor in its normal sampling mode as nearly as
possible. The calibration gas must be injected into the sample
system as close to the sampling probe outlet as practical and
should pass through all CEMS components used during normal
sampling. Challenge the CEMS three non-consecutive times at each
measurement point and record the responses. The duration of each
gas injection should be sufficient to ensure that the CEMS surfaces
are conditioned.
7.1.1 Calculations. Summarize the results on a data
sheet. Average the differences between the instrument response and
the certified cylinder gas value for each gas. Calculate the CE
results for the CO monitor according to:
CE = | d/FS | × 100 (1) Where d is the mean difference between the
CEMS response and the known reference concentration, and FS is the
span value. The CE for the O2 monitor is the average percent O2
difference between the O2 monitor and the certified cylinder gas
value for each gas.
7.2 Relative Accuracy Test Procedure. Follow the RA test
procedures in PS 3 (for O2) section 3 and PS 4A (for CO) section
4.
7.3 Alternative RA Procedure. Under some operating
conditions, it may not be possible to obtain meaningful results
using the RA test procedure. This includes conditions where
consistent, very low CO emission or low CO emissions interrupted
periodically by short duration, high level spikes are observed. It
may be appropriate in these circumstances to waive the RA test and
substitute the following procedure.
Conduct a complete CEMS status check following the
manufacturer's written instructions. The check should include
operation of the light source, signal receiver, timing mechanism
functions, data acquisition and data reduction functions, data
recorders, mechanically operated functions, sample filters, sample
line heaters, moisture traps, and other related functions of the
CEMS, as applicable. All parts of the CEMS must be functioning
properly before the RA requirement can be waived. The instrument
must also successfully passed the CE and CD specifications.
Substitution of the alternate procedure requires approval of the
Regional Administrator.
8. Bibliography
1. 40 CFR Part 266, Appendix IX, section 2, “Performance
Specifications for Continuous Emission Monitoring Systems.”
Performance Specification 5 - Specifications and Test Procedures
for TRS Continuous Emission Monitoring Systems in Stationary
Sources 1.0 Scope and Application
1.1 Analytes.
Analyte
CAS No.
Total Reduced
Sulfur (TRS)
NA
1.2 Applicability. This specification is for evaluating the
applicability of TRS continuous emission monitoring systems (CEMS)
at the time of installation or soon after and whenever specified in
an applicable subpart of the regulations. The CEMS may include
oxygen monitors which are subject to Performance Specification 3
(PS 3).
1.3 The definitions, performance specification, test procedures,
calculations and data analysis procedures for determining
calibration drifts (CD) and relative accuracy (RA) of PS 2,
sections 3.0, 8.0, and 12.0, respectively, apply to this
specification.
2.0 Summary of Performance Specification
The CD and RA tests are conducted to determine conformance of
the CEMS to the specification.
3.0 Definitions
Same as in section 3.0 of PS 2.
4.0 Interferences [Reserved] 5.0 Safety
This performance specification may involve hazardous materials,
operations, and equipment. This performance specification may not
address all of the safety problems associated with its use. It is
the responsibility of the user to establish appropriate safety and
health practices and determine the applicable regulatory
limitations prior to performing this performance specification. The
CEMS user's manual should be consulted for specific precautions to
be taken with regard to the analytical procedures.
6.0 Equipment and Supplies
Same as section 6.0 of PS 2.
7.0 Reagents and Standards
Same as section 7.0 of PS 2.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Relative Accuracy Test Procedure. Sampling Strategy for
reference method (RM) Tests, Number of RM Tests, and Correlation of
RM and CEMS Data are the same as PS 2, sections 8.4.3, 8.4.4, and
8.4.5, respectively.
Note:
For Method 16, a sample is made up of at least three separate
injects equally spaced over time. For Method 16A, a sample is
collected for at least 1 hour. For Method 16B, you must analyze a
minimum of three aliquots spaced evenly over the test period.
Note:
For Method 16, a sample is made up of at least three separate
injects equally space over time. For Method 16A, a sample is
collected for at least 1 hour.
8.2 Reference Methods. Unless otherwise specified in the
applicable subpart of the regulations, Method 16, Method 16A, 16B
or other approved alternative is the RM for TRS.
9.0 Quality Control [Reserved] 10.0 Calibration and Standardization
[Reserved] 11.0 Analytical Procedure
Sample collection and analysis are concurrent for this
performance specification (see section 8.0). Refer to the reference
method for specific analytical procedures.
12.0 Calculations and Data Analysis
Same as section 12.0 of PS 2.
13.0 Method Performance
13.1 Calibration Drift. The CEMS detector calibration must not
drift or deviate from the reference value of the calibration gas by
more than 5 percent of the established span value for 6 out of 7
test days. This corresponds to 1.5 ppm drift for Subpart BB sources
where the span value is 30 ppm. If the CEMS includes pollutant and
diluent monitors, the CD must be determined separately for each in
terms of concentrations (see PS 3 for the diluent
specifications).
13.2 Relative Accuracy. The RA of the CEMS must be no greater
than 20 percent when the average RM value is used to calculate RA
or 10 percent when the applicable emission standard is used to
calculate RA.
1. Department of Commerce. Experimental Statistics, National
Bureau of Standards, Handbook 91. 1963. Paragraphs 3-3.1.4, p.
3-31.
2. A Guide to the Design, Maintenance and Operation of TRS
Monitoring Systems. National Council for Air and Stream Improvement
Technical Bulletin No. 89. September 1977.
3. Observation of Field Performance of TRS Monitors on a Kraft
Recovery Furnace. National Council for Air and Stream Improvement
Technical Bulletin No. 91. January 1978.
18.0 Tables, Diagrams, Flowcharts, and Validation Data
Same as section 18.0 of PS 2.
Performance Specification 6 - Specifications and Test Procedures
for Continuous Emission Rate Monitoring Systems in Stationary
Sources 1.0 Scope and Application
1.1 Applicability. This specification is used for evaluating the
acceptability of continuous emission rate monitoring systems
(CERMSs).
1.2 The installation and measurement location specifications,
performance specification test procedure, calculations, and data
analysis procedures, of Performance Specifications (PS 2), sections
8.0 and 12, respectively, apply to this specification.
2.0 Summary of Performance Specification
The calibration drift (CD) and relative accuracy (RA) tests are
conducted to determine conformance of the CERMS to the
specification.
3.0 Definitions
The definitions are the same as in section 3 of PS 2, except
this specification refers to the continuous emission rate
monitoring system rather than the continuous emission monitoring
system. The following definitions are added:
3.1 Continuous Emission Rate Monitoring System (CERMS).
The total equipment required for the determining and recording the
pollutant mass emission rate (in terms of mass per unit of
time).
3.2 Flow Rate Sensor. That portion of the CERMS that
senses the volumetric flow rate and generates an output
proportional to that flow rate. The flow rate sensor shall have
provisions to check the CD for each flow rate parameter that it
measures individually (e.g., velocity, pressure).
4.0 Interferences [Reserved] 5.0 Safety
This performance specification may involve hazardous materials,
operations, and equipment. This performance specification may not
address all of the safety problems associated with its use. It is
the responsibility of the user to establish appropriate safety and
health practices and determine the applicable regulatory
limitations prior to performing this performance specification. The
CERMS users manual should be consulted for specific precautions to
be taken with regard to the analytical procedures.
6.0 Equipment and Supplies
Same as section 6.0 of PS 2.
7.0 Reagents and Standards
Same as section 7.0 of PS 2.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Calibration Drift Test Procedure.
8.1.1 The CD measurements are to verify the ability of the CERMS
to conform to the established CERMS calibrations used for
determining the emission rate. Therefore, if periodic automatic or
manual adjustments are made to the CERMS zero and calibration
settings, conduct the CD tests immediately before these
adjustments, or conduct them in such a way that CD can be
determined.
8.1.2 Conduct the CD tests for pollutant concentration at the
two values specified in section 6.1.2 of PS 2. For other parameters
that are selectively measured by the CERMS (e.g., velocity,
pressure, flow rate), use two analogous values (e.g., Low:
0-20% of full scale, High: 50-100% of full scale). Introduce to the
CERMS the reference signals (these need not be certified). Record
the CERMS response to each and subtract this value from the
respective reference value (see example data sheet in Figure
6-1).
8.2 Relative Accuracy Test Procedure.
8.2.1 Sampling Strategy for reference method (RM) Tests,
Correlation of RM and CERMS Data, and Number of RM Tests are the
same as PS 2, sections 8.4.3, 8.4.5, and 8.4.4, respectively.
Summarize the results on a data sheet. An example is shown in
Figure 6-1. The RA test may be conducted during the CD test
period.
8.2.2 Reference Methods. Unless otherwise specified in the
applicable subpart of the regulations, the RM for the pollutant gas
is the Appendix A method that is cited for compliance test
purposes, or its approved alternatives. Methods 2, 2A, 2B, 2C, or
2D, as applicable, are the RMs for the determination of volumetric
flow rate.
9.0 Quality Control [Reserved] 10.0 Calibration and Standardization
[Reserved] 11.0 Analytical Procedure
Same as section 11.0 of PS 2.
12.0 Calculations and Data Analysis
Same as section 12.0 of PS 2.
13.0 Method Performance
13.1 Calibration Drift. Since the CERMS includes analyzers for
several measurements, the CD shall be determined separately for
each analyzer in terms of its specific measurement. The calibration
for each analyzer associated with the measurement of flow rate
shall not drift or deviate from each reference value of flow rate
by more than 3 percent of the respective high-level reference value
over the CD test period (e.g., seven-day) associated with
the pollutant analyzer. The CD specification for each analyzer for
which other PSs have been established (e.g., PS 2 for SO2
and NOX), shall be the same as in the applicable PS.
13.2 CERMS Relative Accuracy. Calculate the CERMS Relative
Accuracy using Eq. 2-6 of section 12 of Performance Specification
2. The RA of the CERMS shall be no greater than 20 percent of the
mean value of the RM's test data in terms of the units of the
emission standard, or in cases where the average emissions for the
test are less than 50 percent of the applicable standard,
substitute the emission standard value in the denominator of Eq.
2-6 in place of the RM.
1. Brooks, E.F., E.C. Beder, C.A. Flegal, D.J. Luciani, and R.
Williams. Continuous Measurement of Total Gas Flow Rate from
Stationary Sources. U.S. Environmental Protection Agency. Research
Triangle Park, North Carolina. Publication No. EPA-650/2-75-020.
February 1975. 248 p.
18.0 Tables, Diagrams, Flowcharts, and Validation Data
Run No.
Date and
time
Emission rate
(kg/hr) a
CERMS
RMs
Difference
(RMs-CERMS)
1
2
3
4
5
6
7
8
9
a The RMs and CERMS data as
corrected to a consistent basis (i.e., moisture, temperature, and
pressure conditions).
Figure 6-1 - Emission Rate Determinations Performance Specification
7 - Specifications and Test Procedures for Hydrogen Sulfide
Continuous Emission Monitoring Systems in Stationary Sources 1.0
Scope and Application
1.1 Analytes.
Analyte
CAS No.
Hydrogen
Sulfide
7783-06-4
1.2 Applicability.
1.2.1 This specification is to be used for evaluating the
acceptability of hydrogen sulfide (H2S) continuous emission
monitoring systems (CEMS) at the time of or soon after installation
and whenever specified in an applicable subpart of the
regulations.
1.2.2 This specification is not designed to evaluate the
installed CEMS performance over an extended period of time nor does
it identify specific calibration techniques and other auxiliary
procedures to assess CEMS performance. The source owner or
operator, however, is responsible to calibrate, maintain, and
operate the CEMS. To evaluate CEMS performance, the Administrator
may require, under section 114 of the Act, the source owner or
operator to conduct CEMS performance evaluations at other times
besides the initial test. See section 60.13(c).
2.0 Summary
Calibration drift (CD) and relative accuracy (RA) tests are
conducted to determine that the CEMS conforms to the
specification.
3.0 Definitions
Same as section 3.0 of PS 2.
4.0 Interferences [Reserved] 5.0 Safety
The procedures required under this performance specification may
involve hazardous materials, operations, and equipment. This
performance specification may not address all of the safety
problems associated with these procedures. It is the responsibility
of the user to establish appropriate safety problems associated
with these procedures. It is the responsibility of the user to
establish appropriate safety and health practices and determine the
application regulatory limitations prior to performing these
procedures. The CEMS user's manual and materials recommended by the
reference method should be consulted for specific precautions to be
taken.
6.0 Equipment and Supplies
6.1 Instrument Zero and Span. This specification is the same as
section 6.1 of PS 2.
6.2 Calibration Drift. The CEMS calibration must not drift or
deviate from the reference value of the calibration gas or
reference source by more than 5 percent of the established span
value for 6 out of 7 test days (e.g., the established span value is
300 ppm for Subpart J fuel gas combustion devices).
6.3 Relative Accuracy. The RA of the CEMS must be no greater
than 20 percent when the average reference method (RM) value is
used to calculate RA or 10 percent when the applicable emission
standard is used to calculate RA.
7.0 Reagents and Standards
Same as section 7.0 of PS 2.
8.0 Sample Collection, Preservation, Storage, and Transport.
8.1 Installation and Measurement Location Specification. Same as
section 8.1 of PS 2.
8.2 Pretest Preparation. Same as section 8.2 of PS 2.
8.3 Calibration Drift Test Procedure. Same as section 8.3 of PS
2.
8.4 Relative Accuracy Test Procedure.
8.4.1 Sampling Strategy for RM Tests, Number of RM Tests,
Correlation of RM and CEMS Data, and Calculations. These are the
same as that in PS-2, Sections 8.4.3 (except as specified below),
8.4.4, 8.4.5, and 8.4.6, respectively.
8.4.2 Reference Methods. Unless otherwise specified in an
applicable subpart of the regulation, Methods 11, 15, and 16 may be
used for the RM for this PS.
8.4.2.1 Sampling Time Per Run - Method 11. A sampling run, when
Method 11 (integrated sampling) is used, shall consist of a single
measurement for at least 10 minutes and 0.010 dscm (0.35 dscf).
Each sample shall be taken at approximately 30-minute
intervals.
8.4.2.2 Sampling Time Per Run - Methods 15 and 16. The sampling
run shall consist of two injections equally spaced over a 30-minute
period following the procedures described in the particular method.
Note: Caution! Heater or non-approved electrical probes should not
be used around explosive or flammable sources.
8.5 Reporting. Same as section 8.5 of PS 2.
9.0 Quality Control [Reserved] 10.0 Calibration and
Standardizations [Reserved] 11.0 Analytical Procedures
Sample Collection and analysis are concurrent for this PS (see
section 8.0). Refer to the RM for specific analytical
procedures.
1. U.S. Environmental Protection Agency. Standards of
Performance for New Stationary Sources; Appendix B; Performance
Specifications 2 and 3 for SO2, NOX, CO2, and O2 Continuous
Emission Monitoring Systems; Final Rule. 48 CFR 23608. Washington,
D.C. U.S. Government Printing Office. May 25, 1983.
2. U.S. Government Printing Office. Gaseous Continuous Emission
Monitoring Systems - Performance Specification Guidelines for SO2,
NOX, CO2, O2, and TRS. U.S. Environmental Protection Agency.
Washington, D.C. EPA-450/3-82-026. October 1982. 26 p.
3. Maines, G.D., W.C. Kelly (Scott Environmental Technology,
Inc.), and J.B. Homolya. Evaluation of Monitors for Measuring H2S
in Refinery Gas. Prepared for the U.S. Environmental Protection
Agency. Research Triangle Park, N.C. Contract No. 68-02-2707. 1978.
60 p.
4. Ferguson, B.B., R.E. Lester (Harmon Engineering and Testing),
and W.J. Mitchell. Field Evaluation of Carbon Monoxide and Hydrogen
Sulfide Continuous Emission Monitors at an Oil Refinery. Prepared
for the U.S. Environmental Protection Agency. Research Triangle
Park, N.C. Publication No. EPA-600/4-82-054. August 1982. 100
p.
5. Letter to RAMCON Environmental Corp. from Robert Kellam,
December 27, 1992.
17.0 Tables, Diagrams, Flowcharts, and Validation Data
Same as section 18.0 of PS 2.
Performance Specification 8 - Performance Specifications for
Volatile Organic Compound Continuous Emission Monitoring Systems in
Stationary Sources 1.0 Scope and Application
1.1 Analytes. Volatile Organic Compounds (VOCs).
1.2 Applicability.
1.2.1 This specification is to be used for evaluating a
continuous emission monitoring system (CEMS) that measures a
mixture of VOC's and generates a single combined response value.
The VOC detection principle may be flame ionization (FI),
photoionization (PI), non-dispersive infrared absorption (NDIR), or
any other detection principle that is appropriate for the VOC
species present in the emission gases and that meets this
performance specification. The performance specification includes
procedures to evaluate the acceptability of the CEMS at the time of
or soon after its installation and whenever specified in emission
regulations or permits. This specification is not designed to
evaluate the installed CEMS performance over an extended period of
time, nor does it identify specific calibration techniques and
other auxiliary procedures to assess the CEMS performance. The
source owner or operator, however, is responsible to calibrate,
maintain, and operate the CEMS properly. To evaluate the CEMS
performance, the Administrator may require, under section 114 of
the Act, the operator to conduct CEMS performance evaluations in
addition to the initial test. See section 60.13(c).
1.2.2 In most emission circumstances, most VOC monitors can
provide only a relative measure of the total mass or volume
concentration of a mixture of organic gases, rather than an
accurate quantification. This problem is removed when an emission
standard is based on a total VOC measurement as obtained with a
particular detection principle. In those situations where a true
mass or volume VOC concentration is needed, the problem can be
mitigated by using the VOC CEMS as a relative indicator of total
VOC concentration if statistical analysis indicates that a
sufficient margin of compliance exists for this approach to be
acceptable. Otherwise, consideration can be given to calibrating
the CEMS with a mixture of the same VOC's in the same proportions
as they actually occur in the measured source. In those
circumstances where only one organic species is present in the
source, or where equal incremental amounts of each of the organic
species present generate equal CEMS responses, the latter choice
can be more easily achieved.
2.0 Summary of Performance Specification
2.1 Calibration drift and relative accuracy tests are conducted
to determine adherence of the CEMS with specifications given for
those items. The performance specifications include criteria for
installation and measurement location, equipment and performance,
and procedures for testing and data reduction.
3.0 Definitions.
Same as section 3.0 of PS 2.
4.0 Interferences [Reserved] 5.0 Safety
The procedures required under this performance specification may
involve hazardous materials, operations, and equipment. This
performance specification may not address all of the safety
problems associated with these procedures. It is the responsibility
of the user to establish appropriate safety problems associated
with these procedures. It is the responsibility of the user to
establish appropriate safety and health practices and determine the
application regulatory limitations prior to performing these
procedures. The CEMS user's manual and materials recommended by the
reference method should be consulted for specific precautions to be
taken.
6.0 Equipment and Supplies
6.1 VOC CEMS Selection. When possible, select a VOC CEMS with
the detection principle of the reference method specified in the
regulation or permit (usually either FI, NDIR, or PI). Otherwise,
use knowledge of the source process chemistry, previous emission
studies, or gas chromatographic analysis of the source gas to
select an appropriate VOC CEMS. Exercise extreme caution in
choosing and installing any CEMS in an area with explosive hazard
potential.
6.2 Data Recorder Scale. Same as section 6.1 of PS 2.
7.0 Reagents and Standards [Reserved] 8.0 Sample Collection,
Preservation, Storage, and Transport
8.1 Installation and Measurement Location Specifications. Same
as section 8.1 of PS 2.
8.2 Pretest Preparation. Same as section 8.2 of PS 2.
8.3 Calibration Drift Test Procedure. Same as section 8.3 of PS
2.
8.4 Reference Method (RM). Use the method specified in the
applicable regulation or permit, or any approved alternative, as
the RM.
8.5 Sampling Strategy for RM Tests, Correlation of RM and CEMS
Data, and Number of RM Tests. Follow PS 2, sections 8.4.3, 8.4.5,
and 8.4.4, respectively.
8.6 Reporting. Same as section 8.5 of PS 2.
9.0 Quality Control [Reserved] 10.0 Calibration and Standardization
[Reserved] 11.0 Analytical Procedure
Sample collection and analysis are concurrent for this PS (see
section 8.0). Refer to the RM for specific analytical
procedures.
12.0 Calculations and Data Analysis
Same as section 12.0 of PS 2.
13.0 Method Performance
13.1 Calibration Drift. The CEMS calibration must not drift by
more than 2.5 percent of the span value.
13.2 CEMS Relative Accuracy. Unless stated otherwise in the
regulation or permit, the RA of the CEMS must not be greater than
20 percent of the mean value of the RM test data in terms of the
units of the emission standard, or 10 percent of the applicable
standard, whichever is greater.
17.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]
Performance Specification 8A - Specifications and Test Procedures
for Total Hydrocarbon Continuous Monitoring Systems in Stationary
Sources 1. Applicability and Principle
1.1 Applicability. These performance specifications apply
to hydrocarbon (HC) continuous emission monitoring systems (CEMS)
installed on stationary sources. The specifications include
procedures which are intended to be used to evaluate the
acceptability of the CEMS at the time of its installation or
whenever specified in regulations or permits. The procedures are
not designed to evaluate CEMS performance over an extended period
of time. The source owner or operator is responsible for the proper
calibration, maintenance, and operation of the CEMS at all
times.
1.2 Principle. A gas sample is extracted from the source
through a heated sample line and heated filter to a flame
ionization detector (FID). Results are reported as volume
concentration equivalents of propane. Installation and measurement
location specifications, performance and equipment specifications,
test and data reduction procedures, and brief quality assurance
guidelines are included in the specifications. Calibration drift,
calibration error, and response time tests are conducted to
determine conformance of the CEMS with the specifications.
2. Definitions
2.1 Continuous Emission Monitoring System (CEMS). The
total equipment used to acquire data, which includes sample
extraction and transport hardware, analyzer, data recording and
processing hardware, and software. The system consists of the
following major subsystems:
2.1.1 Sample Interface. That portion of the system that
is used for one or more of the following: Sample acquisition,
sample transportation, sample conditioning, or protection of the
analyzer from the effects of the stack effluent.
2.1.2 Organic Analyzer. That portion of the system that
senses organic concentration and generates an output proportional
to the gas concentration.
2.1.3 Data Recorder. That portion of the system that
records a permanent record of the measurement values. The data
recorder may include automatic data reduction capabilities.
2.2 Instrument Measurement Range. The difference between
the minimum and maximum concentration that can be measured by a
specific instrument. The minimum is often stated or assumed to be
zero and the range expressed only as the maximum.
2.3 Span or Span Value. Full scale instrument measurement
range. The span value must be documented by the CEMS manufacturer
with laboratory data.
2.4 Calibration Gas. A known concentration of a gas in an
appropriate diluent gas.
2.5 Calibration Drift (CD). The difference in the CEMS
output readings from the established reference value after a stated
period of operation during which no unscheduled maintenance,
repair, or adjustment takes place. A CD test is performed to
demonstrate the stability of the CEMS calibration over time.
2.6 Response Time. The time interval between the start of
a step change in the system input (e.g., change of calibration gas)
and the time when the data recorder displays 95 percent of the
final value.
2.7 Accuracy. A measurement of agreement between a
measured value and an accepted or true value, expressed as the
percentage difference between the true and measured values relative
to the true value. For these performance specifications, accuracy
is checked by conducting a calibration error (CE) test.
2.8 Calibration Error (CE). The difference between the
concentration indicated by the CEMS and the known concentration of
the cylinder gas. A CE test procedure is performed to document the
accuracy and linearity of the monitoring equipment over the entire
measurement range.
2.9 Performance Specification Test (PST) Period. The
period during which CD, CE, and response time tests are
conducted.
2.10 Centroidal Area. A concentric area that is
geometrically similar to the stack or duct cross section and is no
greater than 1 percent of the stack or duct cross-sectional
area.
3. Installation and Measurement Location Specifications
3.1 CEMS Installation and Measurement Locations. The CEMS
must be installed in a location in which measurements
representative of the source's emissions can be obtained. The
optimum location of the sample interface for the CEMS is determined
by a number of factors, including ease of access for calibration
and maintenance, the degree to which sample conditioning will be
required, the degree to which it represents total emissions, and
the degree to which it represents the combustion situation in the
firebox (where applicable). The location should be as free from
in-leakage influences as possible and reasonably free from severe
flow disturbances. The sample location should be at least two
equivalent duct diameters downstream from the nearest control
device, point of pollutant generation, or other point at which a
change in the pollutant concentration or emission rate occurs and
at least 0.5 diameter upstream from the exhaust or control device.
The equivalent duct diameter is calculated as per 40 CFR part 60,
appendix A, method 1, section 2.1. If these criteria are not
achievable or if the location is otherwise less than optimum, the
possibility of stratification should be investigated as described
in section 3.2. The measurement point must be within the centroidal
area of the stack or duct cross section.
3.2 Stratification Test Procedure. Stratification is
defined as a difference in excess of 10 percent between the average
concentration in the duct or stack and the concentration at any
point more than 1.0 meter from the duct or stack wall. To determine
whether effluent stratification exists, a dual probe system should
be used to determine the average effluent concentration while
measurements at each traverse point are being made. One probe,
located at the stack or duct centroid, is used as a stationary
reference point to indicate the change in effluent concentration
over time. The second probe is used for sampling at the traverse
points specified in 40 CFR part 60 appendix A, method 1. The
monitoring system samples sequentially at the reference and
traverse points throughout the testing period for five minutes at
each point.
4. CEMS Performance and Equipment Specifications
If this method is applied in highly explosive areas, caution and
care must be exercised in choice of equipment and installation.
4.1 Flame Ionization Detector (FID) Analyzer. A heated
FID analyzer capable of meeting or exceeding the requirements of
these specifications. Heated systems must maintain the temperature
of the sample gas between 150 °C (300 °F) and 175 °C (350 °F)
throughout the system. This requires all system components such as
the probe, calibration valve, filter, sample lines, pump, and the
FID to be kept heated at all times such that no moisture is
condensed out of the system. The essential components of the
measurement system are described below:
4.1.1 Sample Probe. Stainless steel, or equivalent, to
collect a gas sample from the centroidal area of the stack
cross-section.
4.1.2 Sample Line. Stainless steel or Teflon tubing to
transport the sample to the analyzer.
Note:
Mention of trade names or specific products does not constitute
endorsement by the Environmental Protection Agency.
4.1.3 Calibration Valve Assembly. A heated three-way
valve assembly to direct the zero and calibration gases to the
analyzer is recommended. Other methods, such as quick-connect
lines, to route calibration gas to the analyzers are
applicable.
4.1.4 Particulate Filter. An in-stack or out-of-stack
sintered stainless steel filter is recommended if exhaust gas
particulate loading is significant. An out-of-stack filter must be
heated.
4.1.5 Fuel. The fuel specified by the manufacturer (e.g.,
40 percent hydrogen/60 percent helium, 40 percent hydrogen/60
percent nitrogen gas mixtures, or pure hydrogen) should be
used.
4.1.6 Zero Gas. High purity air with less than 0.1 parts
per million by volume (ppm) HC as methane or carbon equivalent or
less than 0.1 percent of the span value, whichever is greater.
4.1.7 Calibration Gases. Appropriate concentrations of
propane gas (in air or nitrogen). Preparation of the calibration
gases should be done according to the procedures in EPA Protocol 1.
In addition, the manufacturer of the cylinder gas should provide a
recommended shelf life for each calibration gas cylinder over which
the concentration does not change by more than ±2 percent from the
certified value.
4.2 CEMS Span Value. 100 ppm propane. The span value must
be documented by the CEMS manufacturer with laboratory data.
4.3 Daily Calibration Gas Values. The owner or operator
must choose calibration gas concentrations that include zero and
high-level calibration values.
4.3.1 The zero level may be between zero and 0.1 ppm (zero and
0.1 percent of the span value).
4.3.2 The high-level concentration must be between 50 and 90 ppm
(50 and 90 percent of the span value).
4.4 Data Recorder Scale. The strip chart recorder,
computer, or digital recorder must be capable of recording all
readings within the CEMS' measurement range and must have a
resolution of 0.5 ppm (0.5 percent of span value).
4.5 Response Time. The response time for the CEMS must
not exceed 2 minutes to achieve 95 percent of the final stable
value.
4.6 Calibration Drift. The CEMS must allow the
determination of CD at the zero and high-level values. The CEMS
calibration response must not differ by more than ±3 ppm (±3
percent of the span value) after each 24-hour period of the 7-day
test at both zero and high levels.
4.7 Calibration Error. The mean difference between the
CEMS and reference values at all three test points listed below
must be no greater than 5 ppm (±5 percent of the span value).
4.7.1 Zero Level. Zero to 0.1 ppm (0 to 0.1 percent of
span value).
4.7.2 Mid-Level. 30 to 40 ppm (30 to 40 percent of span
value).
4.7.3 High-Level. 70 to 80 ppm (70 to 80 percent of span
value).
4.8 Measurement and Recording Frequency. The sample to be
analyzed must pass through the measurement section of the analyzer
without interruption. The detector must measure the sample
concentration at least once every 15 seconds. An average emission
rate must be computed and recorded at least once every 60
seconds.
4.9 Hourly Rolling Average Calculation. The CEMS must
calculate every minute an hourly rolling average, which is the
arithmetic mean of the 60 most recent 1-minute average values.
4.10 Retest. If the CEMS produces results within the
specified criteria, the test is successful. If the CEMS does not
meet one or more of the criteria, necessary corrections must be
made and the performance tests repeated.
5. Performance Specification Test (PST) Periods
5.1 Pretest Preparation Period. Install the CEMS, prepare
the PTM test site according to the specifications in section 3, and
prepare the CEMS for operation and calibration according to the
manufacturer's written instructions. A pretest conditioning period
similar to that of the 7-day CD test is recommended to verify the
operational status of the CEMS.
5.2 Calibration Drift Test Period. While the facility is
operating under normal conditions, determine the magnitude of the
CD at 24-hour intervals for seven consecutive days according to the
procedure given in section 6.1. All CD determinations must be made
following a 24-hour period during which no unscheduled maintenance,
repair, or adjustment takes place. If the combustion unit is taken
out of service during the test period, record the onset and
duration of the downtime and continue the CD test when the unit
resumes operation.
5.3 Calibration Error Test and Response Time Test
Periods. Conduct the CE and response time tests during the CD
test period.
6. Performance Specification Test Procedures
6.1 Relative Accuracy Test Audit (RATA) and Absolute
Calibration Audits (ACA). The test procedures described in this
section are in lieu of a RATA and ACA.
6.2 Calibration Drift Test.
6.2.1 Sampling Strategy. Conduct the CD test at 24-hour
intervals for seven consecutive days using calibration gases at the
two daily concentration levels specified in section 4.3. Introduce
the two calibration gases into the sampling system as close to the
sampling probe outlet as practical. The gas must pass through all
CEM components used during normal sampling. If periodic automatic
or manual adjustments are made to the CEMS zero and calibration
settings, conduct the CD test immediately before these adjustments,
or conduct it in such a way that the CD can be determined. Record
the CEMS response and subtract this value from the reference
(calibration gas) value. To meet the specification, none of the
differences may exceed 3 percent of the span of the CEM.
6.2.2 Calculations. Summarize the results on a data
sheet. An example is shown in Figure 1. Calculate the differences
between the CEMS responses and the reference values.
6.3 Response Time. The entire system including sample
extraction and transport, sample conditioning, gas analyses, and
the data recording is checked with this procedure.
6.3.1 Introduce the calibration gases at the probe as near to
the sample location as possible. Introduce the zero gas into the
system. When the system output has stabilized (no change greater
than 1 percent of full scale for 30 sec), switch to monitor stack
effluent and wait for a stable value. Record the time (upscale
response time) required to reach 95 percent of the final stable
value.
6.3.2 Next, introduce a high-level calibration gas and repeat
the above procedure. Repeat the entire procedure three times and
determine the mean upscale and downscale response times. The longer
of the two means is the system response time.
6.4 Calibration Error Test Procedure.
6.4.1 Sampling Strategy. Challenge the CEMS with zero gas
and EPA Protocol 1 cylinder gases at measurement points within the
ranges specified in section 4.7.
6.4.1.1 The daily calibration gases, if Protocol 1, may be used
for this test.
6.4.1.2 Operate the CEMS as nearly as possible in its normal
sampling mode. The calibration gas should be injected into the
sampling system as close to the sampling probe outlet as practical
and must pass through all filters, scrubbers, conditioners, and
other monitor components used during normal sampling. Challenge the
CEMS three non-consecutive times at each measurement point and
record the responses. The duration of each gas injection should be
for a sufficient period of time to ensure that the CEMS surfaces
are conditioned.
6.4.2 Calculations. Summarize the results on a data
sheet. An example data sheet is shown in Figure 2. Average the
differences between the instrument response and the certified
cylinder gas value for each gas. Calculate three CE results
according to Equation 1. No confidence coefficient is used in CE
calculations.
7. Equations
Calibration Error. Calculate CE using Equation 1.
Where:
d = Mean difference between CEMS response and the known
reference concentration, determined using Equation 2. Where: di =
Individual difference between CEMS response and the known reference
concentration. 8. Reporting
At a minimum, summarize in tabular form the results of the CD,
response time, and CE test, as appropriate. Include all data
sheets, calculations, CEMS data records, and cylinder gas or
reference material certifications.
9.
References
1. Measurement of Volatile Organic Compounds-Guideline Series.
U.S. Environmental Protection Agency, Research Triangle Park, North
Carolina, 27711, EPA-450/2-78-041, June 1978.
2. Traceability Protocol for Establishing True Concentrations of
Gases Used for Calibration and Audits of Continuous Source Emission
Monitors (Protocol No. 1). U.S. Environmental Protection Agency
ORD/EMSL, Research Triangle Park, North Carolina, 27711, June
1978.
3. Gasoline Vapor Emission Laboratory Evaluation-Part 2. U.S.
Environmental Protection Agency, OAQPS, Research Triangle Park,
North Carolina, 27711, EMB Report No. 76-GAS-6, August 1975.
Performance Specification 9 - Specifications and Test Procedures
for Gas Chromatographic Continuous Emission Monitoring Systems in
Stationary Sources 1.0 Scope and Application
1.1 Applicability. These requirements apply to continuous
emission monitoring systems (CEMSs) that use gas chromatography
(GC) to measure gaseous organic compound emissions. The
requirements include procedures intended to evaluate the
acceptability of the CEMS at the time of its installation and
whenever specified in regulations or permits. Quality assurance
procedures for calibrating, maintaining, and operating the CEMS
properly at all times are also given in this procedure.
2.0 Summary of Performance Specification
2.1 Calibration precision, calibration error, and performance
audit tests are conducted to determine conformance of the CEMS with
these specifications. Daily calibration and maintenance
requirements are also specified.
3.0 Definitions
3.1 Gas Chromatograph (GC). That portion of the system that
separates and detects organic analytes and generates an output
proportional to the gas concentration. The GC must be temperature
controlled.
Note:
The term temperature controlled refers to the ability to
maintain a certain temperature around the column.
Temperature-programmable GC is not required for this performance
specification, as long as all other requirements for precision,
linearity and accuracy listed in this performance specification are
met. It should be noted that temperature programming a GC will
speed up peak elution, thus allowing increased sampling
frequency.
3.1.1 Column. Analytical column capable of separating the
analytes of interest.
3.1.2 Detector. A detection system capable of detecting and
quantifying all analytes of interest.
3.1.3 Integrator. That portion of the system that quantifies the
area under a particular sample peak generated by the GC.
3.1.4 Data Recorder. A strip chart recorder, computer, or
digital recorder capable of recording all readings within the
instrument's calibration range.
3.2 Calibration Precision. The error between triplicate
injections of each calibration standard.
4.0 Interferences [Reserved] 5.0 Safety
The procedures required under this performance specification may
involve hazardous materials, operations, and equipment. This
performance specification does not purport to address all of the
safety problems associated with these procedures. It is the
responsibility of the user to establish appropriate safety problems
associated with these procedures. It is the responsibility of the
user to establish appropriate safety and health practices and
determine the application regulatory limitations prior to
performing these procedures. The CEMS user's manual and materials
recommended by the reference method should be consulted for
specific precautions to be taken.
6.0 Equipment and Supplies
6.1 Presurvey Sample Analysis and GC Selection. Determine the
pollutants to be monitored from the applicable regulation or permit
and determine the approximate concentration of each pollutant (this
information can be based on past compliance test results). Select
an appropriate GC configuration to measure the organic compounds.
The GC components should include a heated sample injection loop (or
other sample introduction systems), separatory column,
temperature-controlled oven, and detector. If the source chooses
dual column and/or dual detector configurations, each
column/detector is considered a separate instrument for the purpose
of this performance specification and thus the procedures in this
performance specification shall be carried out on each system. If
this method is applied in highly explosive areas, caution should be
exercised in selecting the equipment and method of
installation.
6.2 Sampling System. The sampling system shall be heat traced
and maintained at a minimum of 120 °C with no cold spots. All
system components shall be heated, including the probe, calibration
valve, sample lines, sampling loop (or sample introduction system),
GC oven, and the detector block (when appropriate for the type of
detector being utilized, e.g., flame ionization
detector).
7.0 Reagents and Standards
7.1 Calibration Gases. Obtain three concentrations of
calibration gases certified by the manufacturer to be accurate to
within 2 percent of the value on the label. A gas dilution system
may be used to prepare the calibration gases from a high
concentration certified standard if the gas dilution system meets
the requirements specified in Test Method 205, 40 CFR Part 51,
Appendix M. The performance test specified in Test Method 205 shall
be repeated quarterly, and the results of the Method 205 test shall
be included in the report. The calibration gas concentration of
each target analyte shall be as follows (measured concentration is
based on the presurvey concentration determined in section
6.1).
Note:
If the low level calibration gas concentration falls at or below
the limit of detection for the instrument for any target pollutant,
a calibration gas with a concentration at 4 to 5 times the limit of
detection for the instrument may be substituted for the low-level
calibration gas listed in section 7.1.1.
7.1.1 Low-level. 40-60 percent of measured concentration.
7.1.2 Mid-level. 90-110 percent of measured concentration.
7.1.3 High-level. 140-160 percent of measured concentration, or
select highest expected concentration.
7.2 Performance Audit Gas. Performance Audit Gas is an
independent cylinder gas or cylinder gas mixture. A certified EPA
audit gas shall be used, when possible. A gas mixture containing
all the target compounds within the calibration range and certified
by EPA's Traceability Protocol for Assay and Certification of
Gaseous Calibration Standards may be used when EPA performance
audit materials are not available. If a certified EPA audit gas or
a traceability protocol gas is not available, use a gas
manufacturer standard accurate to 2 percent.
8.0 Sample Collection, Preservation, Storage, and Transport
8.1 Installation and Measurement Location Specifications.
Install the CEMs in a location where the measurements are
representative of the source emissions. Consider other factors,
such as ease of access for calibration and maintenance purposes.
The location should not be close to air in-leakages. The sampling
location should be at least two equivalent duct diameters
downstream from the nearest control device, point of pollutant
generation, or other point at which a change in the pollutant
concentration or emission rate occurs. The location should be at
least 0.5 diameter upstream from the exhaust or control device. To
calculate equivalent duct diameter, see section 12.2 of Method 1
(40 CFR Part 60, Appendix A). Sampling locations not conforming to
the requirements in this section may be used if necessary upon
approval of the Administrator.
8.2 Pretest Preparation Period. Using the procedures described
in Method 18
(40 CFR Part 60, Appendix A), perform initial tests to determine GC
conditions that provide good resolution and minimum analysis time
for compounds of interest. Resolution interferences that may occur
can be eliminated by appropriate GC column and detector choice or
by shifting the retention times through changes in the column flow
rate and the use of temperature programming.
8.3 Seven (7)-Day Calibration Error (CE) Test Period. At the
beginning of each 24-hour period, set the initial instrument set
points by conducting a multi-point calibration for each compound.
The multi-point calibration shall meet the requirements in sections
13.1, 13.2, and 13.3. Throughout the 24-hour period, sample and
analyze the stack gas at the sampling intervals prescribed in the
regulation or permit. At the end of the 24-hour period, inject the
calibration gases at three concentrations for each compound in
triplicate and determine the average instrument response. Determine
the CE for each pollutant at each concentration using Equation 9-2.
Each CE shall be ≤10 percent. Repeat this procedure six more times
for a total of 7 consecutive days.
8.4 Performance Audit Test Periods. Conduct the performance
audit once during the initial 7-day CE test and quarterly
thereafter. Performance Audit Tests must be conducted through the
entire sampling and analyzer system. Sample and analyze the EPA
audit gas(es) (or the gas mixture) three times. Calculate the
average instrument response. Results from the performance audit
test must meet the requirements in sections 13.3 and 13.4.
8.5 Reporting. Follow the reporting requirements of the
applicable regulation or permit. If the reporting requirements
include the results of this performance specification, summarize in
tabular form the results of the CE tests. Include all data sheets,
calculations, CEMS data records, performance audit results, and
calibration gas concentrations and certifications.
9.0 Quality Control [Reserved] 10.0 Calibration and Standardization
10.1 Multi-Point Calibration. After initial startup of the GC,
after routine maintenance or repair, or at least once per month,
conduct a multi-point calibration of the GC for each target
analyte. Calibration is performed at the instrument independent of
the sample transport system. The multi-point calibration for each
analyte shall meet the requirements in sections 13.1, 13.2, and
13.3.
10.2 Daily Calibration. Once every 24 hours, analyze the
mid-level calibration standard for each analyte in triplicate.
Calibration is performed at the instrument independent of the
sample transport system. Calculate the average instrument response
for each analyte. The average instrument response shall not vary by
more than 10 percent from the certified concentration value of the
cylinder for each analyte. If the difference between the analyzer
response and the cylinder concentration for any target compound is
greater than 10 percent, immediately inspect the instrument making
any necessary adjustments, and conduct an initial multi-point
calibration as described in section 10.1.
11.0 Analytical Procedure. Sample Collection and Analysis Are
Concurrent for This Performance Specification (See section 8.0)
12.0 Calculations and Data Analysis
12.1 Nomenclature.
Cm = average instrument response, ppm. Ca = cylinder gas value,
ppm. F = Flow rate of stack gas through sampling system, in
Liters/min. n = Number of measurement points. r 2 = Coefficient of
determination. V = Sample system volume, in Liters, which is the
volume inside the sample probe and tubing leading from the stack to
the sampling loop. x = CEMS response. y = Actual value of
calibration standard.
12.2 Coefficient of Determination. Calculate r 2 using linear
regression analysis and the average concentrations obtained at
three calibration points as shown in Equation 9-1.
12.3 Calibration Error Determination. Determine the percent
calibration error (CE) at each concentration for each pollutant
using the following equation.
12.4 Sampling System Time Constant (T).
13.0 Method Performance
13.1 Calibration Error (CE). The CEMS must allow the
determination of CE at all three calibration levels. The average
CEMS calibration response must not differ by more than 10 percent
of calibration gas value at each level after each 24-hour period
and after any triplicate calibration response check.
13.2 Calibration Precision and Linearity. For each triplicate
injection at each concentration level for each target analyte, any
one injection shall not deviate more than 5 percent from the
average concentration measured at that level. When the CEMS
response is evaluated over three concentration levels, the linear
regression curve for each organic compound shall be determined
using Equation 9-1 and must have an r 2 ≥0.995.
13.3 Measurement Frequency. The sample to be analyzed shall flow
continuously through the sampling system. The sampling system time
constant shall be ≤5 minutes or the sampling frequency specified in
the applicable regulation, whichever is less. Use Equation 9-3 to
determine T. The analytical system shall be capable of measuring
the effluent stream at the frequency specified in the appropriate
regulation or permit.
13.4 Audit Test Error. Determine the error for each average
pollutant measurement using the Equation 9-2 in section 12.3. Each
error shall be less than or equal to 10 percent of the cylinder gas
certified value. Report the audit results including the average
measured concentration, the error and the certified cylinder
concentration of each pollutant as part of the reporting
requirements in the appropriate regulation or permit.
14.0 Pollution Prevention [Reserved] 15.0 Waste Management
[Reserved] 16.0 References [Reserved] 17.0 Tables, Diagrams,
Flowcharts, and Validation Data [Reserved] Performance
Specification 11 - Specifications and Test Procedures for
Particulate Matter Continuous Emission Monitoring Systems at
Stationary Sources 1.0 What Are the Purpose and Applicability of
Performance Specification 11?
The purpose of Performance Specification 11 (PS-11) is to
establish the initial installation and performance procedures that
are required for evaluating the acceptability of a particulate
matter (PM) continuous emission monitoring system (CEMS); it is not
to evaluate the ongoing performance of your PM CEMS over an
extended period of time, nor to identify specific calibration
techniques and auxiliary procedures to assess CEMS performance. You
will find procedures for evaluating the ongoing performance of a PM
CEMS in Procedure 2 of Appendix F - Quality Assurance Requirements
for Particulate Matter Continuous Emission Monitoring Systems Used
at Stationary Sources.
1.1 Under what conditions does PS-11 apply to my PM CEMS? The
PS-11 applies to your PM CEMS if you are required by any provision
of Title 40 of the Code of Federal Regulations (CFR) to install and
operate PM CEMS.
1.2 When must I comply with PS-11? You must comply with PS-11
when directed by the applicable rule that requires you to install
and operate a PM CEMS.
1.3 What other monitoring must I perform? To report your PM
emissions in units of the emission standard, you may need to
monitor additional parameters to correct the PM concentration
reported by your PM CEMS. Your CEMS may include the components
listed in paragraphs (1) through (3) of this section:
(1) A diluent monitor (i.e., O2, CO2, or other CEMS
specified in the applicable regulation), which must meet its own
performance specifications (also found in this appendix),
(2) Auxiliary monitoring equipment to allow measurement,
determination, or input of the flue gas temperature, pressure,
moisture content, and/or dry volume of stack effluent sampled,
and
(3) An automatic sampling system. The performance of your PM
CEMS and the establishment of its correlation to manual reference
method measurements must be determined in units of mass
concentration as measured by your PM CEMS (e.g., milligrams
per actual cubic meter (mg/acm) or milligrams per dry standard
cubic meter (mg/dscm)).
2.0 What Are the Basic Requirements of PS-11?
The PS-11 requires you to perform initial installation and
calibration procedures that confirm the acceptability of your CEMS
when it is installed and placed into operation. You must develop a
site-specific correlation of your PM CEMS response against manual
gravimetric reference method measurements (including those made
using EPA Methods 5, 5I, or 17).
2.1 What types of PM CEMS technologies are covered? Several
different types of PM CEMS technologies (e.g., light
scattering, Beta attenuation, etc.) can be designed with in-situ or
extractive sample gas handling systems. Each PM CEMS technology and
sample gas handling technology has certain site-specific
advantages. You should select and install a PM CEMS that is
appropriate for the flue gas conditions at your source.
2.2 How is PS-11 different from other performance
specifications? The PS-11 is based on a technique of correlating PM
CEMS responses relative to emission concentrations determined by
the reference method. This technique is called “the correlation.”
This differs from CEMS used to measure gaseous pollutants that have
available calibration gases of known concentration. Because the
type and characteristics of PM vary from source to source, a single
PM correlation, applicable to all sources, is not possible.
2.3 How are the correlation data handled? You must carefully
review your manual reference method data and your PM CEMS responses
to include only valid, high-quality data. For the correlation, you
must convert the manual reference method data to measurement
conditions (e.g., wet or dry basis) that are consistent with
your PM CEMS. Then, you must correlate the manual method and PM
CEMS data in terms of the output as received from the monitor
(e.g., milliamps). At the appropriate PM CEMS response
specified in section 13.2 of this performance specification, you
must calculate the confidence interval half range and tolerance
interval half range as a percentage of the applicable PM
concentration emission limit and compare the confidence interval
and tolerance interval percentages with the performance criteria.
Also, you must calculate the correlation coefficient and compare
the correlation coefficient with the applicable performance
criterion specified in section 13.2 of this performance
specification.
Situations may arise where you will need two or more
correlations. If you need multiple correlations, you must collect
sufficient data for each correlation, and each correlation must
satisfy the performance criteria specified in section 13.2 of this
performance specification.
2.4 How do I design my PM CEMS correlation program? When
planning your PM CEMS correlation effort, you must address each of
the items in paragraphs (1) through (7) of this section to enhance
the probability of success. You will find each of these elements
further described in this performance specification or in the
applicable reference method procedure.
(1) What type of PM CEMS should I select? You should select a PM
CEMS that is appropriate for your source with technical
consideration for potential factors such as interferences,
site-specific configurations, installation location, flue gas
conditions, PM concentration range, and other PM characteristics.
You can find guidance on which technology is best suited for
specific situations in our report “Current Knowledge of Particulate
Matter (PM) Continuous Emission Monitoring” (PM CEMS Knowledge
Document, see section 16.5).
(2) Where should I install my PM CEMS? Your PM CEMS must be
installed in a location that is most representative of PM
emissions, as determined by the reference method, such that the
correlation between PM CEMS response and emissions determined by
the reference method will meet these performance specifications.
Care must be taken in selecting a location and measurement point to
minimize problems due to flow disturbances, cyclonic flow, and
varying PM stratification.
(3) How should I record my CEMS data? You need to ensure that
your PM CEMS and data logger are set up to collect and record all
normal emission levels and excursions. You must ensure that your
data logger and PM CEMS have been properly programmed to accept and
transfer status signals of valid monitor operation (e.g.,
flags for internal calibration, suspect data, or maintenance
periods).
(4) What CEMS data should I review? You must review drift data
daily to document proper operation. You must also ensure that any
audit material is appropriate for the typical operating range of
your PM CEMS.
(5) How long should I operate my PM CEMS before conducting the
initial correlation test? You should allow sufficient time for your
PM CEMS to operate for you to become familiar with your PM
CEMS.
(i) You should observe PM CEMS response over time during normal
and varying process conditions. This will ensure that your PM CEMS
has been properly set up to operate at a range that is compatible
with the concentrations and characteristics of PM emissions for
your source. You should use this information to establish the range
of operating conditions necessary to determine the correlations of
PM CEMS data to manual reference method measurements over a wide
operating range.
(ii) You must determine the types of process changes that will
influence, on a definable and repeatable basis, flue gas PM
concentrations and the resulting PM CEMS responses. You may find
this period useful to make adjustments to your planned approach for
operating your PM CEMS at your source. For instance, you may change
the measurement range or batch sampling period to something other
than those you initially planned to use.
(6) How do I conduct the initial correlation test? When
conducting the initial correlation test of your PM CEMS response to
PM emissions determined by the reference method, you must pay close
attention to accuracy and details. Your PM CEMS must be operating
properly. You must perform the manual reference method testing
accurately, with attention to eliminating site-specific systemic
errors. You must coordinate the timing of the manual reference
method testing with the sampling cycle of your PM CEMS. You must
complete a minimum of 15 manual reference method tests. You must
perform the manual reference method testing over the full range of
PM CEMS responses that correspond to normal operating conditions
for your source and control device and will result in the widest
range of emission concentrations.
(7) How should I perform the manual reference method testing?
You must perform the manual reference method testing in accordance
with specific rule requirements, coordinated closely with PM CEMS
and process operations. It is highly recommended that you use
paired trains for the manual reference method testing. You must
perform the manual reference method testing over a suitable PM
concentration range that corresponds to the full range of normal
process and control device operating conditions. Because the manual
reference method testing for this correlation test is not for
compliance reporting purposes, you may conduct the reference method
test runs for less than the typical minimum test run duration of 1
hour.
(8) What do I do with the manual reference method data and PM
CEMS data? You must complete each of the activities in paragraphs
(8)(i) through (v) of this section.
(i) Screen the manual reference method data for validity
(e.g., isokinetics, leak checks), quality assurance, and
quality control (e.g., outlier identification).
(ii) Screen your PM CEMS data for validity (e.g., daily
drift check requirements) and quality assurance (e.g.,
flagged data).
(iii) Convert the manual reference method test data into
measurement units (e.g., mg/acm) consistent with the
measurement conditions of your PM CEMS.
(iv) Calculate the correlation equation(s) as specified in
section 12.3.
(v) Calculate the correlation coefficient, confidence interval
half range, and tolerance interval half range for the complete set
of PM CEMS and reference method correlation data for comparison
with the correlation performance criteria specified in section
13.2.
2.5 What other procedures must I perform? Before conducting the
initial correlation test, you must successfully complete a 7-day
drift test (See section 8.5).
3.0 What Special Definitions Apply to PS-11?
3.1 “Appropriate Measurement Range of your PM CEMS” means a
measurement range that is capable of recording readings over the
complete range of your source's PM emission concentrations during
routine operations. The appropriate range is determined during the
pretest preparations as specified in section 8.4.
3.2 “Appropriate Data Range for PM CEMS Correlation” means the
data range that reflects the full range of your source's PM
emission concentrations recorded by your PM CEMS during the
correlation test planning period or other normal operations as
defined in the applicable regulations.
3.3 “Batch Sampling” means that gas is sampled on an
intermittent basis and concentrated on a collection medium before
intermittent analysis and follow-up reporting. Beta gauge PM CEMS
are an example of batch sampling devices.
3.4 “Confidence Interval Half Range (CI)” is a statistical term
and means one-half of the width of the 95 percent confidence
interval around the predicted mean PM concentration (y value)
calculated at the PM CEMS response value (x value) where the
confidence interval is narrowest. Procedures for calculating CI are
specified in section 12.3. The CI as a percent of the emission
limit value (CI%) is calculated at the appropriate PM CEMS response
value and must satisfy the criteria specified in section 13.2
(2).
3.5 “Continuous Emission Monitoring System (CEMS)” means all of
the equipment required for determination of PM mass concentration
in units of the emission standard. The sample interface, pollutant
monitor, diluent monitor, other auxiliary data monitor(s), and data
recorder are the major subsystems of your CEMS.
3.6 “Correlation” means the primary mathematical relationship
for correlating the output from your PM CEMS to a PM concentration,
as determined by the PM reference method. The correlation is
expressed in the measurement units that are consistent with the
measurement conditions (e.g., mg/dscm, mg/acm) of your PM
CEMS.
3.7 “Correlation Coefficient (r)” means a quantitative measure
of the association between your PM CEMS outputs and the reference
method measurements. Equations for calculating the r value are
provided in section 12.3(1)(iv) for linear correlations and in
section 12.3(2)(iv) for polynomial correlations.
3.8 “Cycle Time” means the time required to complete one
sampling, measurement, and reporting cycle. For a batch sampling PM
CEMS, the cycle time would start when sample gas is first extracted
from the stack/duct and end when the measurement of that batch
sample is complete and a new result for that batch sample is
produced on the data recorder.
3.9 “Data Recorder” means the portion of your CEMS that provides
a permanent record of the monitor output in terms of response and
status (flags). The data recorder may also provide automatic data
reduction and CEMS control capabilities (see section 6.6).
3.10 “Diluent Monitor and Other Auxiliary Data Monitor(s) (if
applicable)” means the portion of your CEMS that provides the
diluent gas concentration (such as O2 or CO2, as specified by the
applicable regulations), temperature, pressure, and/or moisture
content, and generates an output proportional to the diluent gas
concentration or gas property.
3.11 “Drift Check” means a check of the difference between your
PM CEMS output readings and the established reference value of a
reference standard or procedure after a stated period of operation
during which no unscheduled maintenance, repair, or adjustment took
place. The procedures used to determine drift are specific to the
operating principles of your specific PM CEMS. A drift check
includes both a zero drift check and an upscale drift check.
3.12 “Exponential Correlation” means an exponential equation
used to define the relationship between your PM CEMS output and the
reference method PM concentration, as indicated by Equation
11-37.
3.13 “Flagged Data” means data marked by your CEMS indicating
that the response value(s) from one or more CEMS subsystems is
suspect or invalid or that your PM CEMS is not in
source-measurement operating mode.
3.14 “Linear Correlation” means a first-order mathematical
relationship between your PM CEMS output and the reference method
PM concentration that is linear in form, as indicated by Equation
11-3.
3.15 “Logarithmic Correlation” means a first-order mathematical
relationship between the natural logarithm of your PM CEMS output
and the reference method PM concentration that is linear in form,
as indicated by Equation 11-34.
3.16 “Low-Emitting Source” means a source that operated at no
more than 50 percent of the emission limit during the most recent
performance test, and, based on the PM CEMS correlation, the daily
average emissions for the source, measured in the units of the
applicable emission limit, have not exceeded 50 percent of the
emission limit for any day since the most recent performance
test.
3.17 “Paired Trains” means two reference method trains that are
used to conduct simultaneous measurements of PM concentrations.
Guidance on the use of paired sampling trains can be found in the
PM CEMS Knowledge Document (see section 16.5).
3.18 “Polynomial Correlation” means a second-order equation used
to define the relationship between your PM CEMS output and
reference method PM concentration, as indicated by Equation
11-16.
3.19 “Power Correlation” means an equation used to define a
power function relationship between your PM CEMS output and the
reference method concentration, as indicated by Equation 11-42.
3.20 “Reference Method” means the method defined in the
applicable regulations, but commonly refers to those methods
collectively known as EPA Methods 5, 5I, and 17 (for particulate
matter), found in Appendix A of 40 CFR 60. Only the front half and
dry filter catch portions of the reference method can be correlated
to your PM CEMS output.
3.21 “Reference Standard” means a reference material or
procedure that produces a known and unchanging response when
presented to the pollutant monitor portion of your CEMS. You must
use these standards to evaluate the overall operation of your PM
CEMS, but not to develop a PM CEMS correlation.
3.22 “Response Time” means the time interval between the start
of a step change in the system input and the time when the
pollutant monitor output reaches 95 percent of the final value (see
sections 6.5 and 13.3 for procedures and acceptance criteria).
3.23 “Sample Interface” means the portion of your CEMS used for
one or more of the following: sample acquisition, sample delivery,
sample conditioning, or protection of the monitor from the effects
of the stack effluent.
3.24 “Sample Volume Check” means a check of the difference
between your PM CEMS sample volume reading and the sample volume
reference value.
3.25 “Tolerance Interval half range (TI)” means one-half of the
width of the tolerance interval with upper and lower limits, within
which a specified percentage of the future data population is
contained with a given level of confidence, as defined by the
respective tolerance interval half range equations in section
12.3(1)(iii) for linear correlations and in section 12.3(2)(iii)
for polynomial correlations. The TI as a percent of the emission
limit value (TI%) is calculated at the appropriate PM CEMS response
value specified in section 13.2(3).
3.26 “Upscale Check Value” means the expected response to a
reference standard or procedure used to check the upscale response
of your PM CEMS.
3.27 “Upscale Drift (UD) Check” means a check of the difference
between your PM CEMS output reading and the upscale check
value.
3.28 “Zero Check Value” means the expected response to a
reference standard or procedure used to check the response of your
PM CEMS to particulate-free or low-particulate concentration
conditions.
3.29 “Zero Drift (ZD) Check” means a check of the difference
between your PM CEMS output reading and the zero check value.
3.30 “Zero Point Correlation Value” means a value added to PM
CEMS correlation data to represent low or near zero PM
concentration data (see section 8.6 for rationale and
procedures).
4.0 Are There Any Potential Interferences for My PM CEMS?
Yes, condensible water droplets or condensible acid gas aerosols
(i.e., those with condensation temperatures above those
specified by the reference method) at the measurement location can
be interferences for your PM CEMS if the necessary precautions are
not met.
4.1 Where are interferences likely to occur? Interferences may
develop if your CEMS is installed downstream of a wet air pollution
control system or any other conditions that produce flue gases,
which, at your PM CEMS measurement point, normally or occasionally
contain entrained water droplets or condensible salts before
release to the atmosphere.
4.2 How do I deal with interferences? We recommend that you use
a PM CEMS that extracts and heats representative samples of the
flue gas for measurement to simulate results produced by the
reference method for conditions such as those described in section
4.1. Independent of your PM CEMS measurement technology and
extractive technique, you should have a configuration simulating
the reference method to ensure that:
(1) No formation of new PM or deposition of PM occurs in sample
delivery from the stack or duct; and
(2) No condensate accumulates in the sample flow measurement
apparatus.
4.3 What PM CEMS measurement technologies should I use? You
should use a PM CEMS measurement technology that is free of
interferences from any condensible constituent in the flue gas.
5.0 What Do I Need To Know To Ensure the Safety of Persons Using
PS-11?
People using the procedures required under PS-11 may be exposed
to hazardous materials, operations, site conditions, and equipment.
This performance specification does not purport to address all of
the safety issues associated with its use. It is your
responsibility to establish appropriate safety and health practices
and determine the applicable regulatory limitations before
performing these procedures. You must consult your CEMS user's
manual and other reference materials recommended by the reference
method for specific precautions to be taken.
6.0 What Equipment and Supplies Do I Need?
Different types of PM CEMS use different operating principles.
You should select an appropriate PM CEMS based on your
site-specific configurations, flue gas conditions, and PM
characteristics.
(1) Your PM CEMS must sample the stack effluent continuously or,
for batch sampling PM CEMS, intermittently.
(2) You must ensure that the averaging time, the number of
measurements in an average, the minimum data availability, and the
averaging procedure for your CEMS conform with those specified in
the applicable emission regulation.
(3) Your PM CEMS must include, as a minimum, the equipment
described in sections 6.1 through 6.7.
6.1 What equipment is needed for my PM CEMS's sample interface?
Your PM CEMS's sample interface must be capable of delivering a
representative sample of the flue gas to your PM CEMS. This
subsystem may be required to heat the sample gas to avoid PM
deposition or moisture condensation, provide dilution air, perform
other gas conditioning to prepare the sample for analysis, or
measure the sample volume or flow rate.
(1) If your PM CEMS is installed downstream of a wet air
pollution control system such that the flue gases normally or
occasionally contain entrained water droplets, we recommend that
you select a sampling system that includes equipment to extract and
heat a representative sample of the flue gas for measurement so
that the pollutant monitor portion of your CEMS measures only dry
PM. Heating should be sufficient to raise the temperature of the
extracted flue gas above the water condensation temperature and
should be maintained at all times and at all points in the sample
line from where the flue gas is extracted, including the pollutant
monitor and any sample flow measurement devices.
(2) You must consider the measured conditions of the sample gas
stream to ensure that manual reference method test data are
converted to units of PM concentration that are appropriate for the
correlation calculations. Additionally, you must identify what, if
any, additional auxiliary data from other monitoring and handling
systems are necessary to convert your PM CEMS response into the
units of the PM standard.
(3) If your PM CEMS is an extractive type and your source's flue
gas volumetric flow rate varies by more than 10 percent from
nominal, your PM CEMS should maintain an isokinetic sampling rate
(within 10 percent of true isokinetic). If your extractive-type PM
CEMS does not maintain an isokinetic sampling rate, you must use
actual site-specific data or data from a similar installation to
prove to us, the State, and/or local enforcement agency that
isokinetic sampling is not necessary.
6.2 What type of equipment is needed for my PM CEMS? Your PM
CEMS must be capable of providing an electronic output that can be
correlated to the PM concentration.
(1) Your PM CEMS must be able to perform zero and upscale drift
checks. You may perform these checks manually, but performing these
checks automatically is preferred.
(2) We recommend that you select a PM CEMS that is capable of
performing automatic diagnostic checks and sending instrument
status signals (flags) to the data recorder.
(3) If your PM CEMS is an extractive type that measures the
sample volume and uses the measured sample volume as part of
calculating the output value, your PM CEMS must be able to perform
a check of the sample volume to verify the accuracy of the sample
volume measuring equipment. The sample volume check must be
conducted daily and at the normal sampling rate of your PM
CEMS.
6.3 What is the appropriate measurement range for my PM CEMS?
Initially, your PM CEMS must be set up to measure over the expected
range of your source's PM emission concentrations during routine
operations. You may change the measurement range to a more
appropriate range prior to correlation testing.
6.4 What if my PM CEMS does automatic range switching? Your PM
CEMS may be equipped to perform automatic range switching so that
it is operating in a range most sensitive to the detected
concentrations. If your PM CEMS does automatic range switching, you
must configure the data recorder to handle the recording of data
values in multiple ranges during range-switching intervals.
6.5 What averaging time and sample intervals should be used?
Your CEMS must sample the stack effluent such that the averaging
time, the number of measurements in an average, the minimum
sampling time, and the averaging procedure for reporting and
determining compliance conform with those specified in the
applicable regulation. Your PM CEMS must be designed to meet the
specified response time and cycle time established in this
performance specification (see section 13.3).
6.6 What type of equipment is needed for my data recorder? Your
CEMS data recorder must be able to accept and record electronic
signals from all the monitors associated with your PM CEMS.
(1) Your data recorder must record the signals from your PM CEMS
that can be correlated to PM mass concentrations. If your PM CEMS
uses multiple ranges, your data recorder must identify what range
the measurement was made in and provide range-adjusted results.
(2) Your data recorder must accept and record monitor status
signals (flagged data).
(3) Your data recorder must accept signals from auxiliary data
monitors, as appropriate.
6.7 What other equipment and supplies might I need? You may need
other supporting equipment as defined by the applicable reference
method(s) (see section 7) or as specified by your CEMS
manufacturer.
7.0 What Reagents and Standards Do I Need?
You will need reference standards or procedures to perform the
zero drift check, the upscale drift check, and the sample volume
check.
7.1 What is the reference standard value for the zero drift
check? You must use a zero check value that is no greater than 20
percent of the PM CEMS's response range. You must obtain
documentation on the zero check value from your PM CEMS
manufacturer.
7.2 What is the reference standard value for the upscale drift
check? You must use an upscale check value that produces a response
between 50 and 100 percent of the PM CEMS's response range. For a
PM CEMS that produces output over a range of 4 mA to 20 mA, the
upscale check value must produce a response in the range of 12 mA
to 20 mA. You must obtain documentation on the upscale check value
from your PM CEMS manufacturer.
7.3 What is the reference standard value for the sample volume
check? You must use a reference standard value or procedure that
produces a sample volume value equivalent to the normal sampling
rate. You must obtain documentation on the sample volume value from
your PM CEMS manufacturer.
8.0 What Performance Specification Test Procedure Do I Follow?
You must complete each of the activities in sections 8.1 through
8.8 for your performance specification test.
8.1 How should I select and set up my equipment? You should
select a PM CEMS that is appropriate for your source, giving
consideration to potential factors such as flue gas conditions,
interferences, site-specific configuration, installation location,
PM concentration range, and other PM characteristics. Your PM CEMS
must meet the equipment specifications in sections 6.1 and 6.2.
(1) You should select a PM CEMS that is appropriate for the flue
gas conditions at your source. If your source's flue gas contains
entrained water droplets, we recommend that your PM CEMS include a
sample delivery and conditioning system that is capable of
extracting and heating a representative sample.
(i) Your PM CEMS must maintain the sample at a temperature
sufficient to prevent moisture condensation in the sample line
before analysis of PM.
(ii) If condensible PM is an issue, we recommend that you
operate your PM CEMS to maintain the sample gas temperature at the
same temperature as the reference method filter.
(iii) Your PM CEMS must avoid condensation in the sample flow
rate measurement lines.
(2) Some PM CEMS do not have a wide measurement range
capability. Therefore, you must select a PM CEMS that is capable of
measuring the full range of PM concentrations expected from your
source from normal levels through the emission limit
concentration.
(3) Some PM CEMS are sensitive to particle size changes, water
droplets in the gas stream, particle charge, stack gas velocity
changes, or other factors. Therefore, you should select a PM CEMS
appropriate for the emission characteristics of your source.
(4) We recommend that you consult your PM CEMS vendor to obtain
basic recommendations on the instrument capabilities and setup
configuration. You are ultimately responsible for setup and
operation of your PM CEMS.
8.2 Where do I install my PM CEMS? You must install your PM CEMS
at an accessible location downstream of all pollution control
equipment. You must perform your PM CEMS concentration measurements
from a location considered representative or be able to provide
data that can be corrected to be representative of the total PM
emissions as determined by the manual reference method.
(1) You must select a measurement location that minimizes
problems due to flow disturbances, cyclonic flow, and varying PM
stratification (refer to Method 1 for guidance).
(2) If you plan to achieve higher emissions for correlation test
purposes by adjusting the performance of the air pollution control
device (per section 8.6(4)(i)), you must locate your PM CEMS and
reference method sampling points well downstream of the control
device (e.g., downstream of the induced draft fan), in order
to minimize PM stratification that may be created in these
cases.
8.3 How do I select the reference method measurement location
and traverse points? You must follow EPA Method 1 for identifying
manual reference method traverse points. Ideally, you should
perform your manual reference method measurements at locations that
satisfy the measurement site selection criteria specified in EPA
Method 1 of at least eight duct diameters downstream and at least
two duct diameters upstream of any flow disturbance. Where
necessary, you may conduct testing at a location that is two
diameters downstream and 0.5 diameters upstream of flow
disturbances. If your location does not meet the minimum downstream
and upstream requirements, you must obtain approval from us to test
at your location.
8.4 What are my pretest preparation steps? You must install your
CEMS and prepare the reference method test site according to the
specifications in sections 8.2 and 8.3.
(1) After completing the initial field installation, we
recommend that you operate your PM CEMS according to the
manufacturer's instructions to familiarize yourself with its
operation before you begin correlation testing.
(i) During this initial period of operation, we recommend that
you conduct daily checks (zero and upscale drift and sample volume,
as appropriate), and, when any check exceeds the daily
specification (see section 13.1), make adjustments and perform any
necessary maintenance to ensure reliable operation.
(2) When you are confident that your PM CEMS is operating
properly, we recommend that you operate your CEMS over a
correlation test planning period of sufficient duration to identify
the full range of operating conditions and PM emissions to be used
in your PM CEMS correlation test.
(i) During the correlation test planning period, you should
operate the process and air pollution control equipment over the
normal range of operating conditions, except when you attempt to
produce higher emissions.
(ii) Your data recorder should record PM CEMS response during
the full range of routine process operating conditions.
(iii) You should try to establish the relationships between
operating conditions and PM CEMS response, especially those
conditions that produce the highest PM CEMS response over 15-minute
averaging periods, and the lowest PM CEMS response as well. The
objective is to be able to reproduce the conditions for purposes of
the actual correlation testing discussed in section 8.6.
(3) You must set the response range of your PM CEMS such that
the instrument measures the full range of responses that correspond
to the range of source operating conditions that you will implement
during correlation testing.
(4) We recommend that you perform preliminary reference method
testing after the correlation test planning period. During this
preliminary testing, you should measure the PM emission
concentration corresponding to the highest PM CEMS response
observed during the full range of normal operation, when perturbing
the control equipment, or as the result of PM spiking.
(5) Before performing correlation testing, you must perform a
7-day zero and upscale drift test (see section 8.5).
(6) You must not change the response range of the monitor once
the response range has been set and the drift test successfully
completed.
8.5 How do I perform the 7-day drift test? You must check the
zero (or low-level value between 0 and 20 percent of the response
range of the instrument) and upscale (between 50 and 100 percent of
the instrument's response range) drift. You must perform this check
at least once daily over 7 consecutive days. Your PM CEMS must
quantify and record the zero and upscale measurements and the time
of the measurements. If you make automatic or manual adjustments to
your PM CEMS zero and upscale settings, you must conduct the drift
test immediately before these adjustments, or conduct it in such a
way that you can determine the amount of drift. You will find the
calculation procedures for drift in section 12.1 and the acceptance
criteria for allowable drift in section 13.1.
(1) What is the purpose of 7-day drift tests? The purpose of the
7-day drift test is to demonstrate that your system is capable of
operating in a stable manner and maintaining its calibration for at
least a 7-day period.
(2) How do I conduct the 7-day drift test? To conduct the 7-day
drift test, you must determine the magnitude of the drift once each
day, at 24-hour intervals, for 7 consecutive days while your source
is operating normally.
(i) You must conduct the 7-day drift test at the two points
specified in section 8.5. You may perform the 7-day drift tests
automatically or manually by introducing to your PM CEMS suitable
reference standards (these need not be certified) or by using other
appropriate procedures.
(ii) You must record your PM CEMS zero and upscale response and
evaluate them against the zero check value and upscale check
value.
(3) When must I conduct the 7-day drift test? You must complete
a valid 7-day drift test before attempting the correlation
test.
8.6 How do I conduct my PM CEMS correlation test? You must
conduct the correlation test according to the procedure given in
paragraphs (1) through (5) of this section. If you need multiple
correlations, you must conduct testing and collect at least 15 sets
of reference method and PM CEMS data for calculating each separate
correlation.
(1) You must use the reference method for PM (usually EPA
Methods 5, 5I, or 17) that is prescribed by the applicable
regulations. You may need to perform other reference methods or
performance specifications (e.g., Method 3 for oxygen,
Method 4 for moisture, etc.) depending on the units in which your
PM CEMS reports PM concentration.
(i) We recommend that you use paired reference method trains
when collecting manual PM data to identify and screen the reference
method data for imprecision and bias. Procedures for checking
reference method data for bias and precision can be found in the PM
CEMS Knowledge Document (see section 16.5).
(ii) You may use test runs that are shorter than 60 minutes in
duration (e.g., 20 or 30 minutes). You may perform your PM
CEMS correlation tests during new source performance standards
performance tests or other compliance tests subject to the Clean
Air Act or other statutes, such as the Resource Conservation and
Recovery Act. In these cases, your reference method results
obtained during the PM CEMS correlation test may be used to
determine compliance so long as your source and the test conditions
and procedures (e.g., reference method sample run durations)
are consistent with the applicable regulations and the reference
method.
(iii) You must convert the reference method results to units
consistent with the conditions of your PM CEMS measurements. For
example, if your PM CEMS measures and reports PM emissions in the
units of mass per actual volume of stack gas, you must convert your
reference method results to those units (e.g., mg/acm). If
your PM CEMS extracts and heats the sample gas to eliminate water
droplets, then measures and reports PM emissions under those actual
conditions, you must convert your reference method results to those
same conditions (e.g., mg/acm at 160 °C).
(2) During each test run, you must coordinate process
operations, reference method sampling, and PM CEMS operations. For
example, you must ensure that the process is operating at the
targeted conditions, both reference method trains are sampling
simultaneously (if paired sampling trains are being used), and your
PM CEMS and data logger are operating properly.
(i) You must coordinate the start and stop times of each run
between the reference method sampling and PM CEMS operation. For a
batch sampling PM CEMS, you must start the reference method at the
same time as your PM CEMS sampling.
(ii) You must note the times for port changes (and other periods
when the reference method sampling may be suspended) on the data
sheets so that you can adjust your PM CEMS data accordingly, if
necessary.
(iii) You must properly align the time periods for your PM CEMS
and your reference method measurements to account for your PM CEMS
response time.
(3) You must conduct a minimum of 15 valid runs each consisting
of simultaneous PM CEMS and reference method measurement sets.
(i) You may conduct more than 15 sets of CEMS and reference
method measurements. If you choose this option, you may reject
certain test results so long as the total number of valid test
results you use to determine the correlation is greater than or
equal to 15.
(ii) You must report all data, including the rejected data.
(iii) You may reject the results of up to five test runs without
explanation.
(iv) If you reject the results of more than five test runs, the
basis for rejecting the results of the additional test runs must be
explicitly stated in the reference method, this performance
specification, Procedure 2 of appendix F, or your quality assurance
plan.
(4) Simultaneous PM CEMS and reference method measurements must
be performed in a manner to ensure that the range of data that will
be used to establish the correlation for your PM CEMS is maximized.
You must first attempt to maximize your correlation range by
following the procedures described in paragraphs (4)(i) through
(iv) of this section. If you cannot obtain the three levels as
described in paragraphs (i) through (iv), then you must use the
procedure described in section 8.6(5).
(i) You must attempt to obtain the three different levels of PM
mass concentration by varying process operating conditions, varying
PM control device conditions, or by means of PM spiking.
(ii) The three PM concentration levels you use in the
correlation tests must be distributed over the complete operating
range experienced by your source.
(iii) At least 20 percent of the minimum 15 measured data points
you use should be contained in each of the following levels:
• Level 1: From no PM (zero concentration) emissions to 50
percent of the maximum PM concentration;
• Level 2: 25 to 75 percent of the maximum PM concentration;
and
• Level 3: 50 to 100 percent of the maximum PM
concentration.
(iv) Although the above levels overlap, you may only apply
individual run data to one level.
(5) If you cannot obtain three distinct levels of PM
concentration as described, you must perform correlation testing
over the maximum range of PM concentrations that is practical for
your PM CEMS. To ensure that the range of data used to establish
the correlation for your PM CEMS is maximized, you must follow one
or more of the steps in paragraphs (5)(i) through (iv) of this
section.
(i) Zero point data for in-situ instruments should be
obtained, to the extent possible, by removing the instrument from
the stack and monitoring ambient air on a test bench.
(ii) Zero point data for extractive instruments should be
obtained by removing the extractive probe from the stack and
drawing in clean ambient air.
(iii) Zero point data also can be obtained by performing manual
reference method measurements when the flue gas is free of PM
emissions or contains very low PM concentrations (e.g., when
your process is not operating, but the fans are operating or your
source is combusting only natural gas).
(iv) If none of the steps in paragraphs (5)(i) through (iii) of
this section are possible, you must estimate the monitor response
when no PM is in the flue gas (e.g., 4 mA = 0 mg/acm).
8.7 What do I do with the initial correlation test data for my
PM CEMS? You must calculate and report the results of the
correlation testing, including the correlation coefficient,
confidence interval, and tolerance interval for the PM CEMS
response and reference method correlation data that are use to
establish the correlation, as specified in section 12. You must
include all data sheets, calculations, charts (records of PM CEMS
responses), process data records including PM control equipment
operating parameters, and reference media certifications necessary
to confirm that your PM CEMS met the requirements of this
performance specification. In addition, you must:
(1) Determine the integrated (arithmetic average) PM CEMS output
over each reference method test period;
(2) Adjust your PM CEMS outputs and reference method test data
to the same clock time (considering response time of your PM
CEMS);
(3) Confirm that the reference method results are consistent
with your PM CEMS response in terms of, where applicable, moisture,
temperature, pressure, and diluent concentrations; and
(4) Determine whether any of the reference method test results
do not meet the test method criteria.
8.8 What is the limitation on the range of my PM CEMS
correlation? Although the data you collect during the correlation
testing should be representative of the full range of normal
operating conditions at your source, you must conduct additional
correlation testing if either of the conditions specified in
paragraphs (1) and (2) of this section occurs.
(1) If your source is a low-emitting source, as defined in
section 3.16 of this specification, you must conduct additional
correlation testing if either of the events specified in paragraphs
(1)(i) or (ii) of this section occurs while your source is
operating under normal conditions.
(i) Your source generates 24 consecutive hourly average PM CEMS
responses that are greater than 125 percent of the highest PM CEMS
response (e.g., mA reading) used for the correlation curve
or are greater than the PM CEMS response that corresponds to 50
percent of the emission limit, whichever is greater, or
(ii) The cumulative hourly average PM CEMS responses generated
by your source are greater than 125 percent of the highest PM CEMS
response used for the correlation curve or are greater than the PM
CEMS response that corresponds to 50 percent of the emission limit,
whichever is greater, for more than 5 percent of your PM CEMS
operating hours for the previous 30-day period.
(2) If your source is not a low-emitting source, as defined in
section 3.16 of this specification, you must conduct additional
correlation testing if either of the events specified in paragraph
(i) or (ii) of this section occurs while your source is operating
under normal conditions.
(i) Your source generates 24 consecutive hourly average PM CEMS
responses that are greater than 125 percent of the highest PM CEMS
response (e.g., mA reading) used for the correlation curve,
or
(ii) The cumulative hourly average PM CEMS responses generated
by your source are greater than 125 percent of the highest PM CEMS
response used for the correlation curve for more than 5 percent of
your PM CEMS operating hours for the previous 30-day period.
(3) If additional correlation testing is required, you must
conduct at least three additional test runs under the conditions
that caused the higher PM CEMS response.
(i) You must complete the additional testing and use the
resulting new data along with the previous data to calculate a
revised correlation equation within 60 days after the occurrence of
the event that requires additional testing, as specified in
paragraphs 8.8(1) and (2).
(4) If your source generates consecutive PM CEMS hourly
responses that are greater than 125 percent of the highest PM CEMS
response used to develop the correlation curve for 24 hours or for
a cumulative period that amounts to more than 5 percent of the PM
CEMS operating hours for the previous 30-day period, you must
report the reason for the higher PM CEMS responses.
9.0 What Quality Control Measures Are Required?
Quality control measures for PM CEMS are specified in 40 CFR 60,
Appendix F, Procedure 2.
10.0 What Calibration and Standardization Procedures Must I
Perform? [Reserved] 11.0 What Analytical Procedures Apply to This
Procedure?
Specific analytical procedures are outlined in the applicable
reference method(s).
12.0 What Calculations and Data Analyses Are Needed?
You must determine the primary relationship for correlating the
output from your PM CEMS to a PM concentration, typically in units
of mg/acm or mg/dscm of flue gas, using the calculations and data
analysis process in sections 12.2 and 12.3. You develop the
correlation by performing an appropriate regression analysis
between your PM CEMS response and your reference method data.
12.1 How do I calculate upscale drift and zero drift? You must
determine the difference in your PM CEMS output readings from the
established reference values (zero and upscale check values) after
a stated period of operation during which you performed no
unscheduled maintenance, repair or adjustment.
(1) Calculate the upscale drift (UD) using Equation 11-1:
Where: UD
= The upscale (high-level) drift of your PM CEMS in percent, RCEM =
The measured PM CEMS response to the upscale reference standard, RU
= The pre-established numerical value of the upscale reference
standard, and Rr = The response range of the analyzer.
(2) Calculate the zero drift (ZD) using Equation 11-2:
Where: ZD
= The zero (low-level) drift of your PM CEMS in percent, RCEM = The
measured PM CEMS response to the zero reference standard, RL = The
pre-established numerical value of the zero reference standard, and
Rr = The response range of the analyzer.
(3) Summarize the results on a data sheet similar to that shown
in Table 2 (see section 17).
12.2 How do I perform the regression analysis? You must couple
each reference method PM concentration measurement, y, in the
appropriate units, with an average PM CEMS response, x, over
corresponding time periods. You must complete your PM CEMS
correlation calculations using data deemed acceptable by quality
control procedures identified in 40 CFR 60, Appendix F, Procedure
2.
(1) You must evaluate all flagged or suspect data produced
during measurement periods and determine whether they should be
excluded from your PM CEMS's average.
(2) You must assure that the reference method and PM CEMS
results are on a consistent moisture, temperature, and diluent
basis. You must convert the reference method PM concentration
measurements (dry standard conditions) to the units of your PM CEMS
measurement conditions. The conditions of your PM CEMS measurement
are monitor-specific. You must obtain from your PM CEMS vendor or
instrument manufacturer the conditions and units of measurement for
your PM CEMS.
(i) If your sample gas contains entrained water droplets and
your PM CEMS is an extractive system that measures at actual
conditions (i.e., wet basis), you must use the measured
moisture content determined from the impinger analysis when
converting your reference method PM data to PM CEMS conditions; do
not use the moisture content calculated from a psychrometric chart
based on saturated conditions.
12.3 How do I determine my PM CEMS correlation? To predict PM
concentrations from PM CEMS responses, you must use the calculation
method of least squares presented in paragraphs (1) through (5) of
this section. When performing the calculations, each reference
method PM concentration measurement must be treated as a discrete
data point; if using paired sampling trains, do not average
reference method data pairs for any test run.
This performance specification describes procedures for
evaluating five types of correlation models: linear, polynomial,
logarithmic, exponential, and power. Procedures for selecting the
most appropriate correlation model are presented in section 12.4 of
this specification.
(1) How do I evaluate a linear correlation for my correlation
test data? To evaluate a linear correlation, follow the procedures
described in paragraphs (1)(i) through (iv) of this section.
(i) Calculate the linear correlation equation, which gives the
predicted PM concentration () as a function of the PM CEMS response
(x), as indicated by Equation 11-3:
Where: y = the predicted PM concentration, b0 =
the intercept for the correlation curve, as calculated using
Equation 11-4, b1 = the slope of the correlation curve, as
calculated using Equation 11-6, and x = the PM CEMS response value.
Calculate the y intercept (b0) of the correlation curve using
Equation 11-4:
Where: x = the mean value of the PM CEMS
response data, as calculated using Equation 11-5, and y = the mean
value of the PM concentration data, as calculated using Equation
11-5: Where: xi = the PM CEMS response value
for run i, yi = the PM concentration value for run i, and n = the
number of data points.
Calculate the slope (b1) of the correlation curve using Equation
11-6:
Where: Sxx, Sxy = as calculated using Equation
11-7:
(ii) Calculate the half range of the 95 percent confidence
interval (CI) for the predicted PM concentration () at the mean
value of x, using Equation 11-8:
Where: CI = the half range of the 95 percent
confidence interval for the predicted PM concentration at the mean
x value, tdf,1-a/2 = the value for the t statistic provided in
Table 1 for df = (n - 2), and SL = the scatter or deviation of
values about the correlation curve, which is determined using
Equation 11-9: Calculate the confidence
interval half range for the predicted PM concentration () at the
mean x value as a percentage of the emission limit (CI%) using
Equation 11-10: Where: CI = the half range of
the 95 percent confidence interval for the predicted PM
concentration at the mean x value, and EL = PM emission limit, as
described in section 13.2.
(iii) Calculate the half range of the tolerance interval (TI)
for the predicted PM concentration () at the mean x value using
Equation 11-11:
Where: TI = the half range of the tolerance
interval for the predicted PM concentration () at the mean x value,
kT = as calculated using Equation 11-12, and SL = as calculated
using Equation 11-9: Where: n′ = the number of
test runs (n), un′ = the tolerance factor for 75 percent coverage
at 95 percent confidence provided in Table 1 for df = (n−2), and
vdf = the value from Table 1 for df = (n−2).
Calculate the half range of the tolerance interval for the
predicted PM concentration () at the mean x value as a percentage
of the emission limit (TI%) using Equation 11-13:
Where: TI = the half range of the tolerance
interval for the predicted PM concentration () at the mean x value,
and EL = PM emission limit, as described in section 13.2.
(iv) Calculate the linear correlation coefficient (r) using
Equation 11-14:
Where: SL = as calculated using Equation 11-9,
and Sy = as calculated using Equation 11-15:
(2) How do I evaluate a polynomial correlation for my
correlation test data? To evaluate a polynomial correlation, follow
the procedures described in paragraphs (2)(i) through (iv) of this
section.
(i) Calculate the polynomial correlation equation, which is
indicated by Equation 11-16, using Equations 11-17 through
11-22:
Where: = the PM CEMS concentration predicted by
the polynomial correlation equation, and b0, b1, b2 = the
coefficients determined from the solution to the matrix equation Ab
= B Where: Where: Xi = the PM CEMS response for
run i, Yi = the reference method PM concentration for run i,
and n = the number of test runs.
Calculate the polynomial correlation curve coefficients
(b0, b1, and b2) using Equations 11-19 through
11-21, respectively:
Where:
(ii) Calculate the 95 percent confidence interval half range
(CI) by first calculating the C coefficients (Co to C5) using
Equations 11-23 and 11-24:
Where: Calculate Δ using
Equation 11-25 for each x value: Determine the
x value that corresponds to the minimum value of Δ (Δmin).
Determine the scatter or deviation of values about the polynomial
correlation curve (SP) using Equation 11-26:
Calculate the half range of the 95 percent confidence interval (CI)
for the predicted PM concentration () at the x value that
corresponds to Δmin using Equation 11-27:
Where: df = (n-3), and tdf = as listed in Table 1 (see section 17).
Calculate the half range of the 95 percent confidence interval for
the predicted PM concentration at the x value that corresponds to
Δmin as a percentage of the emission limit (CI%) using Equation
11-28: Where: CI = the half range of the 95
percent confidence interval for the predicted PM concentration at
the x value that corresponds to Δmin, and EL = PM emission limit,
as described in section 13.2.
(iii) Calculate the tolerance interval half range (TI) for the
predicted PM concentration at the x value that corresponds to Δmin,
as indicated in Equation 11-29 for the polynomial correlation,
using Equations 11-30 and 11-31:
Where: un′ = the value
indicated in Table 1 for df = (n′-3), and vdf = the value indicated
in Table 1 for df = (n′ - 3). Calculate the tolerance interval half
range for the predicted PM concentration at the x value that
corresponds to Δmin as a percentage of the emission limit (TI%)
using Equation 11-32: Where: TI = the tolerance
interval half range for the predicted PM concentration at the x
value that corresponds to Δmin, and EL = PM emission limit, as
described in section 13.2.
(iv) Calculate the polynomial correlation coefficient (r) using
Equation 11-33:
Where: SP = as calculated using Equation 11-26,
and Sy = as calculated using Equation 11-15.
(3) How do I evaluate a logarithmic correlation for my
correlation test data? To evaluate a logarithmic correlation, which
has the form indicated by Equation 11-34, follow the procedures
described in paragraphs (3)(i) through (iii) of this section.
(i) Perform a logarithmic transformation of each PM CEMS
response value (x values) using Equation 11-35:
Where: xi′ = is the transformed value of xi,
and Ln(xi) = the natural logarithm of the PM CEMS response for run
i.
(ii) Using the values for xi′ in place of the values for xi,
perform the same procedures used to develop the linear correlation
equation described in paragraph (1)(i) of this section. The
resulting equation has the form indicated by Equation 11-36:
Where: x′ = the natural logarithm of the PM
CEMS response, and the variables , b0, and b1 are as defined in
paragraph (1)(i) of this section.
(iii) Using the values for xi′ in place of the values for xi,
calculate the confidence interval half range at the mean x′ value
as a percentage of the emission limit (CI%), the tolerance interval
half range at the mean x′ value as a percentage of the emission
limit (TI%), and the correlation coefficient (r) using the
procedures described in paragraphs (1)(ii) through (iv) of this
section.
(4) How do I evaluate an exponential correlation for my
correlation test data? To evaluate an exponential correlation,
which has the form indicated by Equation 11-37, follow the
procedures described in paragraphs (4)(i) through (v) of this
section:
(i) Perform a logarithmic transformation of each PM
concentration measurement (y values) using Equation 11-38:
Where: y′i = is the transformed value of yi,
and Ln(yi) = the natural logarithm of the PM concentration
measurement for run i.
(ii) Using the values for y′i in place of the values for yi,
perform the same procedures used to develop the linear correlation
equation described in paragraph (1)(i) of this section. The
resulting equation will have the form indicated by Equation
11-39.
Where: ′ = the predicted log PM concentration
value, b′0 = the natural logarithm of b0, and the variables b0, b1,
and x are as defined in paragraph (1)(i) of this section.
(iii) Using the values for y″i in place of the values for
yi, calculate the half range of the 95 percent confidence
interval (CI′), as described in paragraph (1)(ii) of this section
for CI. Note that CI′ is on the log scale. Next, calculate the
upper and lower 95 percent confidence limits for the mean value y′
using Equations 11-40 and 11-41:
Where: LCL′ = the
lower 95 percent confidence limit for the mean value y′, UCL′ = the
upper 95 percent confidence limit for the mean value y′, y′ = the
mean value of the log-transformed PM concentrations, and CI′ = the
half range of the 95 percent confidence interval for the predicted
PM concentration (′), as calculated in Equation 11-8. Calculate the
half range of the 95 percent confidence interval (CI) on the
original PM concentration scale using Equation 11-42: Where: CI = the
half range of the 95 percent confidence interval on the original PM
concentration scale, and UCL′ and LCL′ are as defined previously.
Calculate the half range of the 95 percent confidence interval for
the predicted PM concentration corresponding to the mean value of x
as a percentage of the emission limit (CI%) using Equation 11-10.
(iv) Using the values for y′i in place of the values for
yi, calculate the half range tolerance interval (TI′), as
described in paragraph (1)(iii) of this section for TI. Note that
TI′ is on the log scale. Next, calculate the half range tolerance
limits for the mean value y′ using Equations 11-43 and 11-44:
Where: LTL′ = the
lower 95 percent tolerance limit for the mean value y′, UTL′ = the
upper 95 percent tolerance limit for the mean value y′, y′, = the
mean value of the log-transformed PM concentrations, and TI′ = the
half range of the 95 percent tolerance interval for the predicted
PM concentration (′), as calculated in Equation 11-11. Calculate
the half range tolerance interval (TI) on the original PM
concentration scale using Equation 11-45: TI = the half
range of the 95 percent tolerance interval on the original PM
scale, and UTL′ and LTL′ are as defined previously. Calculate the
tolerance interval half range for the predicted PM concentration
corresponding to the mean value of x as a percentage of the
emission limit (TI%) using Equation 11-13.
(v) Using the values for y″ i in place of the values for
yi, calculate the correlation coefficient (r) using the
procedure described in paragraph (1)(iv) of this section.
(5) How do I evaluate a power correlation for my correlation
test data? To evaluate a power correlation, which has the form
indicated by Equation 11-46, follow the procedures described in
paragraphs (5)(i) through (v) of this section.
(i) Perform logarithmic transformations of each PM CEMS response
(x values) and each PM concentration measurement (y
values) using Equations 11-35 and 11-38, respectively.
(ii) Using the values for x″i in place of the values for
xi, and the values for y″i in place of the values for
yi, perform the same procedures used to develop the linear
correlation equation described in paragraph (1)(i) of this section.
The resulting equation will have the form indicated by Equation
11-47:
Where: ′
= the predicted log PM concentration value, and x′ = the natural
logarithm of the PM CEMS response values, b′0 = the natural
logarithm of b0, and the variables b0, b1, and
x are as defined in paragraph (1)(i) of this section.
(iii) Using the same procedure described for exponential models
in paragraph (4)(iii) of this section, calculate the half range of
the 95 percent confidence interval for the predicted PM
concentration corresponding to the mean value of x′ as a percentage
of the emission limit.
(iv) Using the same procedure described for exponential models
in paragraph (4)(iv) of this section, calculate the tolerance
interval half range for the predicted PM concentration
corresponding to the mean value of x′ as a percentage of the
emission limit.
(v) Using the values for y′i in place of the values for
yi, calculate the correlation coefficient (r) using the
procedure described in paragraph (1)(iv) of this section.
Note: PS-11 does not address the application of
correlation equations to calculate PM emission concentrations using
PM CEMS response data during normal operations of a PM CEMS.
However, we will provide guidance on the use of specific
correlation models (i.e., logarithmic, exponential, and power
models) to calculate PM concentrations in an operating PM CEMS in
situations when the PM CEMS response values are equal to or less
than zero, and the correlation model is undefined.
12.4 Which correlation model should I use? Follow the procedures
described in paragraphs (1) through (4) of this section to
determine which correlation model you should use.
(1) For each correlation model that you develop using the
procedures described in section 12.3 of this specification, compare
the confidence interval half range percentage, tolerance interval
half range percentage, and correlation coefficient to the
performance criteria specified in section 13.2 of this
specification. You can use the linear, logarithmic, exponential, or
power correlation model if the model satisfies all of the
performance criteria specified in section 13.2 of this
specification. However, to use the polynomial model you first must
check that the polynomial correlation curve satisfies the criteria
for minimum and maximum values specified in paragraph (3) of this
section.
(2) If you develop more than one correlation curve that satisfy
the performance criteria specified in section 13.2 of this
specification, you should use the correlation curve with the
greatest correlation coefficient. If the polynomial model has the
greatest correlation coefficient, you first must check that the
polynomial correlation curve satisfies the criteria for minimum and
maximum values specified in paragraph (3) of this section.
(3) You can use the polynomial model that you develop using the
procedures described in section 12.3(2) if the model satisfies the
performance criteria specified in section 13.2 of this
specification, and the minimum or maximum value of the polynomial
correlation curve does not occur within the expanded data range.
The minimum or maximum value of the polynomial correlation curve is
the point where the slope of the curve equals zero. To determine if
the minimum or maximum value occurs within the expanded data range,
follow the procedure described in paragraphs (3)(i) through (iv) of
this section.
(i) Determine if your polynomial correlation curve has a minimum
or maximum point by comparing the polynomial coefficient b2 to
zero. If b2 is less than zero, the curve has a maximum value. If b2
is greater than zero, the curve has a minimum value. (Note: If b2
equals zero, the correlation curve is linear.)
(ii) Calculate the minimum value using Equation 11-48.
(iii) If your polynomial correlation curve has a minimum point,
you must compare the minimum value to the minimum PM CEMS response
used to develop the correlation curve. If the correlation curve
minimum value is less than or equal to the minimum PM CEMS response
value, you can use the polynomial correlation curve, provided the
correlation curve also satisfies all of the performance criteria
specified in section 13.2 of this specification. If the correlation
curve minimum value is greater than the minimum PM CEMS response
value, you cannot use the polynomial correlation curve to predict
PM concentrations.
(iv) If your polynomial correlation curve has a maximum, the
maximum value must be greater than the allowable extrapolation
limit. If your source is not a low-emitting source, as defined in
section 3.16 of this specification, the allowable extrapolation
limit is 125 percent of the highest PM CEMS response used to
develop the correlation curve. If your source is a low-emitting
source, the allowable extrapolation limit is 125 percent of the
highest PM CEMS response used to develop the correlation curve or
the PM CEMS response that corresponds to 50 percent of the emission
limit, whichever is greater. If the polynomial correlation curve
maximum value is greater than the extrapolation limit, and the
correlation curve satisfies all of the performance criteria
specified in section 13.2 of this specification, you can use the
polynomial correlation curve to predict PM concentrations. If the
correlation curve maximum value is less than the extrapolation
limit, you cannot use the polynomial correlation curve to predict
PM concentrations.
(4) You may petition the Administrator for alternative solutions
or sampling recommendations if the correlation models described in
section 12.3 of this specification do not satisfy the performance
criteria specified in section 13.2 of this specification.
13.0 What Are the Performance Criteria for My PM CEMS?
You must evaluate your PM CEMS based on the 7-day drift check,
the accuracy of the correlation, and the sampling periods and
cycle/response time.
13.1 What is the 7-day drift check performance specification?
Your daily PM CEMS internal drift checks must demonstrate that the
daily drift of your PM CEMS does not deviate from the value of the
reference light, optical filter, Beta attenuation signal, or other
technology-suitable reference standard by more than 2 percent of
the response range. If your CEMS includes diluent and/or auxiliary
monitors (for temperature, pressure, and/or moisture) that are
employed as a necessary part of this performance specification, you
must determine the calibration drift separately for each ancillary
monitor in terms of its respective output (see the appropriate
performance specification for the diluent CEMS specification). None
of the calibration drifts may exceed their individual
specification.
13.2 What performance criteria must my PM CEMS correlation
satisfy? Your PM CEMS correlation must meet each of the minimum
specifications in paragraphs (1), (2), and (3) of this section.
Before confidence and tolerance interval half range percentage
calculations are made, you must convert the emission limit to the
appropriate units of your PM CEMS measurement conditions using the
average of emissions gas property values (e.g., diluent
concentration, temperature, pressure, and moisture) measured during
the correlation test.
(1) The correlation coefficient must satisfy the criterion
specified in paragraph (1)(i) or (ii), whichever applies.
(i) If your source is not a low-emitting source, as defined in
section 3.16 of this specification, the correlation coefficient (r)
must be greater than or equal to 0.85.
(ii) If your source is a low-emitting source, as defined in
section 3.16 of this specification, the correlation coefficient (r)
must be greater than or equal to 0.75.
(2) The confidence interval half range must satisfy the
applicable criterion specified in paragraph (2)(i), (ii), or (iii)
of this section, based on the type of correlation model.
(i) For linear or logarithmic correlations, the 95 percent
confidence interval half range at the mean PM CEMS response value
from the correlation test must be within 10 percent of the PM
emission limit value specified in the applicable regulation.
Therefore, the CI% calculated using Equation 11-10 must be less
than or equal to 10 percent.
(ii) For polynomial correlations, the 95 percent confidence
interval half range at the PM CEMS response value from the
correlation test that corresponds to the minimum value for Δ must
be within 10 percent of the PM emission limit value specified in
the applicable regulation. Therefore, the CI% calculated using
Equation 11-28 must be less than or equal to 10 percent.
(iii) For exponential or power correlations, the 95 percent
confidence interval half range at the mean of the logarithm of the
PM CEMS response values from the correlation test must be within 10
percent of the PM emission limit value specified in the applicable
regulation. Therefore, the CI% calculated using Equation 11-10 must
be less than or equal to 10 percent.
(3) The tolerance interval half range must satisfy the
applicable criterion specified in paragraph (3)(i), (ii), or (iii)
of this section, based on the type of correlation model.
(i) For linear or logarithmic correlations, the half range
tolerance interval with 95 percent confidence and 75 percent
coverage at the mean PM CEMS response value from the correlation
test must be within 25 percent of the PM emission limit value
specified in the applicable regulation. Therefore, the TI%
calculated using Equation 11-13 must be less than or equal to 25
percent.
(ii) For polynomial correlations, the half range tolerance
interval with 95 percent confidence and 75 percent coverage at the
PM CEMS response value from the correlation test that corresponds
to the minimum value for Δ must be within 25 percent of the PM
emission limit value specified in the applicable regulation.
Therefore, the TI% calculated using Equation 11-32 must be less
than or equal to 25 percent.
(iii) For exponential or power correlations, the half range
tolerance interval with 95 percent confidence and 75 percent
coverage at the mean of the logarithm of the PM CEMS response
values from the correlation test must be within 25 percent of the
PM emission limit value specified in the applicable regulation.
Therefore, the TI% calculated using Equation 11-13 must be less
than or equal to 25 percent.
13.3 What are the sampling periods and cycle/response time? You
must document and maintain the response time and any changes in the
response time following installation.
(1) If you have a batch sampling PM CEMS, you must evaluate the
limits presented in paragraphs (1)(i) and (ii) of this section.
(i) The response time of your PM CEMS, which is equivalent to
the cycle time, must be no longer than 15 minutes. In addition, the
delay between the end of the sampling time and reporting of the
sample analysis must be no greater than 3 minutes. You must
document any changes in the response time following
installation.
(ii) The sampling time of your PM CEMS must be no less than 30
percent of the cycle time. If you have a batch sampling PM CEMS,
sampling must be continuous except during pauses when the collected
pollutant on the capture media is being analyzed and the next
capture medium starts collecting a new sample.
13.4 What PM compliance monitoring must I do? You must report
your CEMS measurements in the units of the standard expressed in
the regulations (e.g., mg/dscm @ 7 percent oxygen, pounds
per million Btu (lb/mmBtu), etc.). You may need to install
auxiliary data monitoring equipment to convert the units reported
by your PM CEMS into units of the PM emission standard.
14.0 Pollution Prevention [Reserved] 15.0 Waste Management
[Reserved] 16.0 Which References Are Relevant to This Performance
Specification?
16.1 Technical Guidance Document: Compliance Assurance
Monitoring. U.S. Environmental Protection Agency Office of Air
Quality Planning and Standards Emission Measurement Center. August
1998.
16.2 40 CFR 60, Appendix B, “Performance Specification 2 -
Specifications and Test Procedures for SO2, and NOX, Continuous
Emission Monitoring Systems in Stationary Sources.”
16.3 40 CFR 60, Appendix B, “Performance Specification 1 -
Specification and Test Procedures for Opacity Continuous Emission
Monitoring Systems in Stationary Sources.”
16.4 40 CFR 60, Appendix A, “Method 1 - Sample and Velocity
Traverses for Stationary Sources.”
16.5 “Current Knowledge of Particulate Matter (PM) Continuous
Emission Monitoring.” EPA-454/R-00-039. U.S. Environmental
Protection Agency, Research Triangle Park, NC. September 2000.
16.7 ISO 10155, “Stationary Source Emissions - Automated
Monitoring of Mass Concentrations of Particles: Performance
Characteristics, Test Procedures, and Specifications.” American
National Standards Institute, New York City. 1995.
16.8 Snedecor, George W. and Cochran, William G. (1989),
Statistical Methods, Eighth Edition, Iowa State University
Press.
16.9 Wallis, W. A. (1951) “Tolerance Intervals for Linear
Regression,” in Second Berkeley Symposium on Mathematical
Statistics and Probability, ed. J. Neyman, Berkeley: University of
California Press, pp. 43-51.
17.0 What Reference Tables and Validation Data Are Relevant to
PS-11?
Use the information in Table 1 for determining the confidence
and tolerance interval half ranges. Use Table 2 to record your
7-day drift test data.
Table 1 - Factors for Calculation of
Confidence and Tolerance Interval Half Ranges
df
Student's t,
tdf
Tolerance
interval with 75% coverage and 95% confidence level
vdf (95%)
un′ (75%)
kT
3
3.182
2.920
1.266
3.697
4
2.776
2.372
1.247
2.958
5
2.571
2.089
1.233
2.576
6
2.447
1.915
1.223
2.342
7
2.365
1.797
1.214
2.183
8
2.306
1.711
1.208
2.067
9
2.262
1.645
1.203
1.979
10
2.228
1.593
1.198
1.909
11
2.201
1.551
1.195
1.853
12
2.179
1.515
1.192
1.806
13
2.160
1.485
1.189
1.766
14
2.145
1.460
1.186
1.732
15
2.131
1.437
1.184
1.702
16
2.120
1.418
1.182
1.676
17
2.110
1.400
1.181
1.653
18
2.101
1.384
1.179
1.633
19
2.093
1.370
1.178
1.614
20
2.086
1.358
1.177
1.597
21
2.080
1.346
1.175
1.582
22
2.074
1.335
1.174
1.568
23
2.069
1.326
1.173
1.555
24
2.064
1.316
1.172
1.544
25
2.060
1.308
1.172
1.533
26
2.056
1.300
1.171
1.522
27
2.052
1.293
1.170
1.513
28
2.048
1.286
1.170
1.504
29
2.045
1.280
1.169
1.496
30
2.042
1.274
1.168
1.488
31
2.040
1.268
1.168
1.481
32
2.037
1.263
1.167
1.474
33
2.035
1.258
1.167
1.467
34
2.032
1.253
1.166
1.461
35
2.030
1.248
1.166
1.455
36
2.028
1.244
1.165
1.450
37
2.026
1.240
1.165
1.444
38
2.024
1.236
1.165
1.439
39
2.023
1.232
1.164
1.435
40
2.021
1.228
1.164
1.430
41
2.020
1.225
1.164
1.425
42
2.018
1.222
1.163
1.421
43
2.017
1.218
1.163
1.417
44
2.015
1.215
1.163
1.413
45
2.014
1.212
1.163
1.410
46
2.013
1.210
1.162
1.406
47
2.012
1.207
1.162
1.403
48
2.011
1.204
1.162
1.399
49
2.010
1.202
1.162
1.396
50
2.009
1.199
1.161
1.393
51
2.008
1.197
1.161
1.390
52
2.007
1.195
1.161
1.387
53
2.006
1.192
1.161
1.384
54
2.005
1.190
1.161
1.381
55
2.004
1.188
1.160
1.379
56
2.003
1.186
1.160
1.376
57
2.002
1.184
1.160
1.374
58
2.002
1.182
1.160
1.371
59
2.001
1.180
1.160
1.369
60
2.000
1.179
1.160
1.367
References 16.8 (t values) and 16.9 (vdf and
un′ values).
Table 2 - 7-Day Drift Test Data
Zero drift day #
Date
and
time
Zero check
value
(RL)
PM CEMS
response
(RCEMS)
Difference
(RCEMS−RL)
Zero drift
((RCEMS−RL) /RU) × 100
1
2
3
4
5
6
7
Upscale drift day #
Date
and
time
Upscale
check
value
(RU)
PM CEMS
response
(RCEMS)
Difference
(RCEMS−RU)
Upscale drift
((RCEMS−RU)/RU) × 100%
1
2
3
4
5
6
7
Performance Specification 12A - Specifications and Test Procedures
for Total Vapor Phase Mercury Continuous Emission Monitoring
Systems in Stationary Sources 1.0 Scope and Application
1.1 Analyte. The analyte measured by these procedures and
specifications is total vapor phase mercury (Hg) in the flue gas,
which represents the sum of elemental Hg (Hg°, CAS Number
7439-97-6) and oxidized forms of gaseous Hg (Hg+2), in
concentration units of micrograms per cubic meter (µg/m 3).
1.2 Applicability.
1.2.1 This specification is for evaluating the acceptability of
total vapor phase Hg continuous emission monitoring systems (CEMS)
installed at stationary sources at the time of or soon after
installation and whenever specified in the regulations. The Hg CEMS
must be capable of measuring the total concentration in µg/m 3 of
vapor phase Hg, regardless of speciation, and recording that
concentration at standard conditions on a wet or dry basis. These
specifications do not address measurement of particle bound Hg.
1.2.2 This specification is not designed to evaluate an
installed CEMS's performance over an extended period of time nor
does it identify specific calibration techniques and auxiliary
procedures to assess the CEMS's performance. The source owner or
operator, however, is responsible to calibrate, maintain, and
operate the CEMS properly. The Administrator may require, under
section 114 of the Clean Air Act, the operator to conduct CEMS
performance evaluations at other times besides the initial
performance evaluation test. See §§ 60.13(c) and
63.8(e)(1).
1.2.3 Mercury monitoring approaches not entirely suited to these
specifications may be approvable under the alternative monitoring
or alternative test method provisions of § 60.13(i) and § 63.8(f)
or § 60.8(b)(3) and § 63.7(f), respectively.
2.0 Summary of Performance Specification
Procedures for determining CEMS relative accuracy, linearity,
and calibration drift are outlined. CEMS installation and
measurement location specifications, data reduction procedures, and
performance criteria are included.
3.0 Definitions
3.1 Continuous Emission Monitoring System (CEMS) means
the total equipment required to measure a pollutant concentration.
The system generally consists of the following three major
subsystems:
3.2 Sample Interface means that portion of the CEMS used
for one or more of the following: sample acquisition, sample
transport, sample conditioning, and protection of the monitor from
the effects of the stack effluent.
3.3 Hg Analyzer means that portion of the Hg CEMS that
measures the total vapor phase Hg mass concentration and generates
a proportional output.
3.4 Data Recorder means that portion of the CEMS that
provides a permanent electronic record of the analyzer output. The
data recorder may provide automatic data reduction and CEMS control
capabilities.
3.5 Span Value means the measurement range as specified
in the applicable regulation or other requirement. If the span is
not specified in the applicable regulation or other requirement,
then it must be a value approximately equivalent to two times the
emission standard. Unless otherwise specified, the span value may
be rounded up to the nearest multiple of 10.
3.6 Measurement Error Test means a test procedure in
which the accuracy of the concentrations measured by a CEMS at
three or more points over its measurement range is evaluated using
reference gases. For Hg CEMS, elemental and oxidized Hg (Hg 0 and
mercuric chloride, HgCl2) gas standards of known concentration are
used for this procedure.
3.7 Measurement Error (ME) means the absolute value of
the difference between the concentration indicated by the CEMS and
the known concentration of a reference gas, expressed as a
percentage of the span value, when the entire CEMS, including the
sampling interface, is challenged.
3.8 Calibration Drift (CD) means the absolute value of
the difference between the CEMS output response and either an
upscale Hg reference gas or a zero-level Hg reference gas,
expressed as a percentage of the span value, when the entire CEMS,
including the sampling interface, is challenged after a stated
period of operation during which no unscheduled maintenance or
repair took place.
3.9 Relative Accuracy Test Procedure means a test
procedure consisting of at least nine test runs, in which the
accuracy of the concentrations measured by a CEMS is evaluated by
comparison against concurrent measurements made with a reference
method (RM). Relative accuracy tests repeated on a regular,
on-going basis are referred to as relative accuracy test audits or
RATAs.
3.10 Relative Accuracy (RA) means the absolute mean
difference between the pollutant concentrations determined by the
CEMS and the values determined by the RM plus the 2.5 percent error
confidence coefficient of a series of tests divided by the mean of
the RM tests. Alternatively, for sources with an average RM
concentration less than 5.0 micrograms per standard cubic meter
(µg/scm), the RA may be expressed as the absolute value of the
difference between the mean CEMS and RM values.
4.0 Interferences [Reserved] 5.0 Safety
The procedures required under this performance specification may
involve hazardous materials, operations, and equipment. This
performance specification may not address all of the safety
problems associated with these procedures. It is the responsibility
of the user to establish appropriate safety and health practices
and determine the applicable regulatory limitations prior to
performing these procedures. The CEMS user's manual and materials
recommended by the RM should be consulted for specific precautions
to be taken.
6.0 Equipment and Supplies
6.1 CEMS Equipment Specifications.
6.1.1 Data Recorder Scale. The Hg CEMS data recorder output
range must include the full range of expected Hg concentration
values in the gas stream to be sampled including zero and the span
value.
6.1.2 The Hg CEMS design should also provide for the
determination of CD and ME at a zero value (zero to 20 percent of
the span value) and at upscale values (between 50 and 100 percent
of the span value). The Hg CEMS must be constructed to permit the
introduction of known concentrations of Hg and HgCl2 separately
into the sampling system of the CEMS immediately preceding the
sample extraction filtration system such that the entire CEMS can
be challenged.
6.2 Reference Gas Delivery System. The reference gas delivery
system must be designed so that the flowrate exceeds the sampling
system flow requirements of the CEMS and that the gas is delivered
to the CEMS at atmospheric pressure.
6.3 Other equipment and supplies, as needed by the reference
method used for the Relative Accuracy Test Procedure. See
section 8.6.2.
7.0 Reagents and Standards
7.1 Reference Gases. Reference gas standards are required for
both elemental and oxidized Hg (Hg and mercuric chloride, HgCl2).
The use of National Institute of Standards and Technology
(NIST)-traceable standards and reagents is required. The following
gas concentrations are required.
7.1.1 Zero-level. 0 to 20 percent of the span value.
7.1.2 Mid-level. 50 to 60 percent of the span value.
7.1.3 High-level. 80 to 100 percent of the span value.
7.2 Reference gas standards may also be required for the
reference methods. See section 8.6.2.
8.0 Performance Specification Test Procedure
8.1 Installation and Measurement Location Specifications.
8.1.1 CEMS Installation. Install the CEMS at an accessible
location downstream of all pollution control equipment. Place the
probe outlet or other sampling interface at a point or location in
the stack (or vent) representative of the stack gas concentration
of Hg. Since the Hg CEMS sample system normally extracts gas from a
single point in the stack, a location that has been shown to be
free of stratification for Hg or, alternatively, SO2 is
recommended. If the cause of failure to meet the RA test
requirement is determined to be the measurement location and a
satisfactory correction technique cannot be established, the
Administrator may require the CEMS to be relocated. Measurement
locations and points or paths that are most likely to provide data
that will meet the RA requirements are described in sections 8.1.2
and 8.1.3 below.
8.1.2 Measurement Location. The measurement location should be
(1) at least two equivalent diameters downstream of the nearest
control device, point of pollutant generation or other point at
which a change of pollutant concentration may occur, and (2) at
least half an equivalent diameter upstream from the effluent
exhaust. The equivalent duct diameter is calculated according to
Method 1 in appendix A-1 to this part.
8.1.3 Hg CEMS Sample Extraction Point. Use a sample extraction
point either (1) no less than 1.0 meter from the stack or duct
wall, or (2) within the centroidal velocity traverse area of the
stack or duct cross section. This does not apply to cross-stack,
in-situ measurement systems.
8.2 Measurement Error (ME) Test Procedure. Sequentially inject
each of at least three elemental Hg reference gases (zero,
mid-level, and high level, as defined in section 7.1), three times
each for a total of nine injections. Inject the gases in such a
manner that the entire CEMS is challenged. Do not inject the same
gas concentration twice in succession. At each reference gas
concentration, determine the average of the three CEMS responses
and subtract the average response from the reference gas value.
Calculate the measurement error (ME) using Equation 12-1 by
expressing the absolute value of the difference between the average
CEMS response (A) and the reference gas value (R) as a percentage
of the span (see example data sheet in Figure 12A-1). For
each elemental Hg reference gas, the absolute value of the
difference between the CEMS response and the reference value must
not exceed 5 percent of the span value. If this specification is
not met, identify and correct the problem before proceeding. Repeat
the measurement error test procedure using oxidized Hg reference
gases. For each oxidized Hg reference gas, the absolute value of
the difference between the CEMS response and the reference value
shall not exceed 10 percent of the span value. If this
specification is not met, identify and correct the problem before
proceeding.
8.3 Seven-Day Calibration Drift (CD) Test Procedure.
8.3.1 CD Test Period. While the affected facility is operating
normally, or as specified in an applicable regulation, determine
the magnitude of the CD once each day (at 24-hour intervals, to the
extent practicable) for 7 consecutive unit operating days according
to the procedures in sections 8.3.2 and 8.3.3. The 7 consecutive
unit operating days need not be 7 consecutive calendar days. Use
either Hg° or HgCl2 standards for this test.
8.3.2 The purpose of the CD measurement is to verify the ability
of the CEMS to conform to the established CEMS response used for
determining emission concentrations or emission rates. Therefore,
if periodic automatic or manual adjustments are made to the CEMS
zero and upscale response settings, conduct the CD test immediately
before these adjustments, or conduct it in such a way that the CD
can be determined.
8.3.3 Conduct the CD test using the zero gas specified and
either the mid-level or high-level gas as specified in section 7.1.
Sequentially introduce the reference gases to the CEMS at the
sampling system of the CEMS immediately preceding the sample
extraction filtration system. Record the CEMS response (A) for each
reference gas and, using Equation 12A-2, subtract the corresponding
reference value (R) from the CEMS value, and express the absolute
value of the difference as a percentage of the span value (see
also example data sheet in Figure 12A-2). For each reference
gas, the absolute value of the difference between the CEMS response
and the reference value must not exceed 5 percent of the span
value. If these specifications are not met, identify and correct
the problem before proceeding.
8.4 Relative Accuracy (RA) Test Procedure.
8.4.1 RA Test Period. Conduct the RA test according to the
procedure given in sections 8.4.2 through 8.4.6 while the affected
facility is operating normally, or as specified in an applicable
subpart. The RA test may be conducted during the CD test
period.
8.4.2 Reference Methods (RM). Unless otherwise specified in an
applicable subpart of the regulations, use Method 29, Method 30A,
or Method 30B in appendix A-8 to this part or American Society of
Testing and Materials (ASTM) Method D6784-02 (incorporated by
reference, see § 60.17) as the RM for Hg concentration. For
Method 29 and ASTM Method D6784-02 only, the filterable portion of
the sample need not be included when making comparisons to the CEMS
results. When Method 29, Method 30B, or ASTM D6784-02 is used,
conduct the RM test runs with paired or duplicate sampling systems
and use the average of the vapor phase Hg concentrations measured
by the two trains. When Method 30A is used, paired sampling systems
are not required. If the RM and CEMS measure on a different
moisture basis, data derived with Method 4 in appendix A-3 to this
part must also be obtained during the RA test.
8.4.3 Sampling Strategy for RM Tests. Conduct the RM tests in
such a way that they will yield results representative of the
emissions from the source and can be compared to the CEMS data. The
RM and CEMS locations need not be immediately adjacent. Locate the
RM measurement points in accordance with section 8.1.3 of
Performance Specification 2 (PS 2) in this appendix. It is
preferable to conduct moisture measurements (if needed) and Hg
measurements simultaneously, although moisture measurements that
are taken within an hour of the Hg measurements may be used to
adjust the Hg concentrations to a consistent moisture basis. In
order to correlate the CEMS and RM data properly, note the
beginning and end of each RM test period for each paired RM run
(including the exact time of day) on the CEMS chart recordings or
other permanent record of output.
8.4.4 Number and Length of RM Test Runs. Conduct a minimum of
nine RM test runs. When Method 29, Method 30B, or ASTM D6784-02 is
used, only test runs for which the paired RM trains meet the
relative deviation criteria (RD) of this PS must be used in the RA
calculations. In addition, for Method 29 and ASTM D6784-02, use a
minimum sample time of 2 hours and for Methods 30A and 30B use a
minimum sample time of 30 minutes.
Note:
More than nine sets of RM test runs may be performed. If this
option is chosen, RM test run results may be excluded so long as
the total number of RM test run results used to determine the CEMS
RA is greater than or equal to nine. However, all data must be
reported including the excluded test run data.
8.4.5 Correlation of RM and CEMS Data. Correlate the CEMS and
the RM test data as to the time and duration by first determining
from the CEMS final output (the one used for reporting) the
integrated average pollutant concentration for each RM test period.
Consider system response time, if important, and confirm that the
results are on a consistent moisture basis with the RM test. Then,
compare each integrated CEMS value against the corresponding RM
value. When Method 29, Method 30B, or ASTM D6784-02 is used,
compare each CEMS value against the corresponding average of the
paired RM values.
8.4.6 Paired RM Outliers.
8.4.6.1 When Method 29, Method 30B, or ASTM D6784-02 is used,
outliers are identified through the determination of relative
deviation (RD) of the paired RM tests. Data that do not meet the RD
criteria must be flagged as a data quality problem and may not be
used in the calculation of RA. The primary reason for performing
paired RM sampling is to ensure the quality of the RM data. The
percent RD of paired data is the parameter used to quantify data
quality. Determine RD for paired data points as follows:
Where: Ca and Cb are the Hg concentration
values determined from the paired samples.
8.4.6.2 The minimum performance criteria for RM Hg data is that
RD for any data pair must be ≤10 percent as long as the mean Hg
concentration is greater than 1.0 µg/m 3. If the mean Hg
concentration is less than or equal to 1.0 µg/m 3, the RD must be
≤20 percent or ≤0.2 µg/m 3 absolute difference. Pairs of RM data
exceeding these RD criteria should be eliminated from the data set
used to develop a Hg CEMS correlation or to assess CEMS RA.
8.4.7 Calculate the mean difference between the RM and CEMS
values in the units of micrograms per cubic meter (µg/m 3), the
standard deviation, the confidence coefficient, and the RA
according to the procedures in section 12.0.
8.5 Reporting. At a minimum (check with the appropriate EPA
Regional Office, State or local Agency for additional requirements,
if any), summarize in tabular form the results of the CD tests, the
linearity tests, and the RA test or alternative RA procedure, as
appropriate. Include all data sheets, calculations, charts (records
of CEMS responses), reference gas concentration certifications, and
any other information necessary to confirm that the CEMS meets the
performance criteria.
9.0 Quality Control [Reserved] 10.0 Calibration and Standardization
[Reserved] 11.0 Analytical Procedure
For Method 30A, sample collection and analysis are concurrent.
For the other RM, post-run sample analyses are performed. Refer to
the RM employed for specific analytical procedures.
12.0 Calculations and Data Analysis
Calculate and summarize the RA test results on a data sheet
similar to Figure 12A-3.
12.1 Consistent Basis. All data from the RM and CEMS must be
compared in units of micrograms per standard cubic meter (µg/scm),
on a consistent and identified moisture basis. The values must be
standardized to 20 °C, 760 mm Hg.
12.1.1 Moisture Correction (as applicable). If the RM and CEMS
measure Hg on a different moisture basis, they will need to be
corrected to a consistent basis. Use Equation 12A-4a to correct
data from a wet basis to a dry basis.
Use Equation 12A-4b to correct data from a dry basis to a wet
basis.
Where: Bws is the moisture content of the flue
gas from Method 4, expressed as a decimal fraction (e.g., for 8.0
percent H2O, Bws= 0.08).
12.2 Arithmetic Mean. Calculate d , the arithmetic mean
of the differences (di) of a data set as follows:
Where: n = Number of data points.
12.3 Standard Deviation. Calculate the standard deviation, Sd,
as follows:
12.3 Confidence Coefficient (CC). Calculate the 2.5 percent
error confidence coefficient (one-tailed), CC, as follows:
12.4 Relative Accuracy. Calculate the RA of a set of data as
follows:
Where: |d | = Absolute value of the mean
of the differences (from Equation 12A-5) |CC| = Absolute
value of the confidence coefficient (from Equation 12A-7) RM =
Average reference method value 13.0 Method Performance
13.1 Measurement Error (ME). For Hg 0, the ME must not exceed 5
percent of the span value at the zero-, mid-, and high-level
reference gas concentrations. For HgCl2, the ME must not exceed 10
percent of the span value at the zero-, mid-, and high-level
reference gas concentrations.
13.2 Calibration Drift (CD). The CD must not exceed 5 percent of
the span value on any of the 7 days of the CD test.
13.3 Relative Accuracy (RA). The RA of the CEMS must be no
greater than 20 percent of the mean value of the RM test data in
terms of units of µg/scm. Alternatively, if the mean RM is less
than 5.0 µg/scm, the results are acceptable if the absolute value
of the difference between the mean RM and CEMS values does not
exceed 1.0 µg/scm.
17.1 40 CFR part 60, appendix B, “Performance Specification 2 -
Specifications and Test Procedures for SO2 and NOX Continuous
Emission Monitoring Systems in Stationary Sources.”
17.2 40 CFR part 60, appendix A, “Method 29 - Determination of
Metals Emissions from Stationary Sources.”
17.3 40 CFR part 60, appendix A, “Method 30A - Determination of
Total Vapor Phase Mercury Emissions From Stationary Sources
(Instrumental Analyzer Procedure).
17.4 40 CFR part 60, appendix A, “Method 30B - Determination of
Total Vapor Phase Mercury Emissions From Coal-Fired Combustion
Sources Using Carbon Sorbent Traps.”
17.5 ASTM Method D6784-02, “Standard Test Method for Elemental,
Oxidized, Particle-Bound and Total Mercury in Flue Gas Generated
from Coal-Fired Stationary Sources (Ontario Hydro Method).”
18.0 Tables and Figures
Table 12A-1 - T-Values
n a
t0.975
n a
t0.975
n a
t0.975
2
12.706
7
2.447
12
2.201
3
4.303
8
2.365
13
2.179
4
3.182
9
2.306
14
2.160
5
2.776
10
2.262
15
2.145
6
2.571
11
2.228
16
2.131
a The values in this table are
already corrected for n-1 degrees of freedom. Use n equal to the
number of individual values.
1 Calculate the RD only if paired
samples are taken using RM 30B, RM 29, or ASTM 6784-08. Express RD
as a percentage or, for very low RM concentrations (≤1.0 µg/m
3), as the absolute difference between Ca and Cb.
Performance Specification 12B - Specifications and Test Procedures
for Monitoring Total Vapor Phase Mercury Emissions From Stationary
Sources Using a Sorbent Trap Monitoring System 1.0 Scope and
Application
The purpose of Performance Specification 12B (PS 12B) is to
establish performance benchmarks for, and to evaluate the
acceptability of, sorbent trap monitoring systems used to monitor
total vapor-phase mercury (Hg) emissions in stationary source flue
gas streams. These monitoring systems involve continuous repetitive
in-stack sampling using paired sorbent media traps with periodic
analysis of the time-integrated samples. Persons using PS 12B
should have a thorough working knowledge of Methods 1, 2, 3, 4, 5
and 30B in appendices A-1 through A-3 and A-8 to this part.
1.1 Analyte. The analyte measured by these procedures and
specifications is total vapor phase Hg in the flue gas, which
represents the sum of elemental Hg (Hg 0, CAS Number 7439-97-6) and
gaseous forms of oxidized Hg (i.e., Hg+2) in mass
concentration units of micrograms per dry standard cubic meter
(µg/dscm).
1.2 Applicability
1.2.1 These procedures are only intended for use under
relatively low particulate conditions (e.g., monitoring after all
pollution control devices). This specification is for evaluating
the acceptability of total vapor phase Hg sorbent trap monitoring
systems installed at stationary sources at the time of, or soon
after, installation and whenever specified in the regulations. The
Hg monitoring system must be capable of measuring the total
concentration of vapor phase Hg (regardless of speciation), in
units of µg/dscm.
1.2.2 This specification contains routine procedures and
specifications designed to evaluate an installed sorbent trap
monitoring system's performance over time; Procedure 5 of appendix
F to this part contains additional procedures and specifications
which may be required for long term operation. In addition, the
source owner or operator is responsible to calibrate, maintain, and
operate the monitoring system properly. The Administrator may
require the owner or operator, under section 114 of the Clean Air
Act, to conduct performance evaluations at other times besides the
initial test to evaluate the CEMS performance. See §
60.13(c) and 63.8(e)(1).
2.0 Principle
Known volumes of flue gas are continuously extracted from a
stack or duct through paired, in-stack, pre-spiked sorbent media
traps at appropriate nominal flow rates. The sorbent traps in the
sampling system are periodically exchanged with new ones, prepared
for analysis as needed, and analyzed by any technique that can meet
the performance criteria. For quality-assurance purposes, a section
of each sorbent trap is spiked with Hg 0 prior to sampling.
Following sampling, this section is analyzed separately and a
specified minimum percentage of the spike must be recovered. Paired
train sampling is required to determine method precision.
3.0 Definitions
3.1 Sorbent Trap Monitoring System means the total
equipment required for the collection of gaseous Hg samples using
paired three-partition sorbent traps.
3.2 Relative Accuracy Test Procedure means a test
procedure consisting of at least nine runs, in which the accuracy
of the total vapor phase Hg concentrations measured by the sorbent
trap monitoring system is evaluated by comparison against
concurrent measurements made with a reference method (RM). Relative
accuracy tests repeated on a regular, on-going basis are referred
to as relative accuracy test audits or RATAs.
3.3 Relative Accuracy (RA) means the absolute mean
difference between the pollutant (Hg) concentrations determined by
the sorbent trap monitoring system and the values determined by the
reference method (RM) plus the 2.5 percent error confidence
coefficient of a series of tests divided by the mean of the RM
tests. Alternatively, for low concentration sources, the RA may be
expressed as the absolute value of the difference between the mean
sorbent trap monitoring system and RM values.
3.4 Relative Deviation (RD) means the absolute difference
of the Hg concentration values obtained with a pair of sorbent
traps divided by the sum of those concentrations, expressed as a
percentage. RD is used to assess the precision of the sorbent trap
monitoring system.
3.5 Spike Recovery means the mass of Hg recovered from
the spiked trap section, expressed as a percentage of the amount
spiked. Spike recovery is used to assess sample matrix
interference.
4.0 Interferences [Reserved] 5.0 Safety
The procedures required under this performance specification may
involve hazardous materials, operations, and equipment. This
performance specification may not address all of the safety
problems associated with these procedures. It is the responsibility
of the user to establish appropriate safety and health practices
and determine the applicable regulatory limitations prior to
performing these procedures.
6.0 Equipment and Supplies
6.1 Sorbent Trap Monitoring System Equipment Specifications.
6.1.1 Monitoring System. The equipment described in Method 30B
in appendix A-8 to this part must be used to continuously sample
for Hg emissions, with the substitution of three-section traps in
place of two-section traps, as described below. A typical sorbent
trap monitoring system is shown in Figure 12B-1.
6.1.2 Three-Section Sorbent Traps. The sorbent media used to
collect Hg must be configured in traps with three distinct and
identical segments or sections, connected in series, to be
separately analyzed. section 1 is designated for primary capture of
gaseous Hg. section 2 is designated as a backup section for
determination of vapor-phase Hg breakthrough. section 3 is
designated for quality assurance/quality control (QA/QC) purposes.
section 3 must be spiked with a known amount of gaseous Hg 0 prior
to sampling and later analyzed to determine the spike (and hence
sample) recovery efficiency.
6.1.3 Gaseous Hg 0 Sorbent Trap Spiking System. A known mass of
gaseous Hg 0 must be spiked onto section 3 of each sorbent trap
prior to sampling. Any approach capable of quantitatively
delivering known masses of Hg 0 onto sorbent traps is acceptable.
Several technologies or devices are available to meet this
objective. Their practicality is a function of Hg mass spike
levels. For low levels, NIST-certified or NIST-traceable gas
generators or tanks may be suitable, but will likely require long
preparation times. A more practical, alternative system, capable of
delivering almost any mass required, employs NIST-certified or
NIST-traceable Hg salt solutions (e.g., Hg(NO3)2). With this
system, an aliquot of known volume and concentration is added to a
reaction vessel containing a reducing agent (e.g., stannous
chloride); the Hg salt solution is reduced to Hg 0 and purged onto
section 3 of the sorbent trap by using an impinger sparging
system.
6.1.4 Sample Analysis Equipment. Any analytical system capable
of quantitatively recovering and quantifying total gaseous Hg from
sorbent media is acceptable provided that the analysis can meet the
performance criteria in Table 12B-1 in section 9 of this
performance specification. Candidate recovery techniques include
leaching, digestion, and thermal desorption. Candidate analytical
techniques include ultraviolet atomic fluorescence (UV AF);
ultraviolet atomic absorption (UV AA), with and without gold
trapping; and in-situ X-ray fluorescence (XRF).
7.0 Reagents and Standards
Only NIST-certified or NIST-traceable calibration gas standards
and reagents must be used for the tests and procedures required
under this performance specification. The sorbent media may be any
collection material (e.g., carbon, chemically treated filter,
etc.) capable of quantitatively capturing and recovering for
subsequent analysis, all gaseous forms of Hg in the emissions from
the intended application. Selection of the sorbent media must be
based on the material's ability to achieve the performance criteria
contained in this method as well as the sorbent's vapor phase Hg
capture efficiency for the emissions matrix and the expected
sampling duration at the test site.
8.0 Performance Specification Test Procedure
8.1 Installation and Measurement Location Specifications.
8.1.1 Selection of Monitoring Site. Sampling site information
should be obtained in accordance with Method 1 in appendix A-1 to
this part. Place the probe inlet at a point or location in the
stack (or vent) downstream of all pollution control equipment and
representative of the stack gas concentration of Hg. A location
that has been shown to be free of stratification for Hg or,
alternatively, SO2 is recommended. An estimation of the expected
stack Hg concentration is required to establish a target sample
flow rate, total gas sample volume, and the mass of Hg 0 to be
spiked onto section 3 of each sorbent trap.
8.1.2 Pre-sampling Spiking of Sorbent Traps. Based on the
estimated Hg concentration in the stack, the target sample rate and
the target sampling duration, calculate the expected mass loading
for section 1 of each sorbent trap (see section 12.1 of this
performance specification). The pre-sampling spike to be added to
section 3 of each sorbent trap must be within ±50 percent of the
expected section 1 mass loading. Spike section 3 of each sorbent
trap at this level, as described in section 6.1.3 of this
performance specification. For each sorbent trap, keep a record of
the mass of Hg 0 added to section 3. This record must include, at a
minimum, the identification number of the trap, the date and time
of the spike, the name of the analyst performing the procedure, the
method of spiking, the mass of Hg 0 added to section 3 of the trap
(µg), and the supporting calculations.
8.1.3 Pre-monitoring Leak Check. Perform a leak check with the
sorbent traps in place in the sampling system. Draw a vacuum in
each sample train. Adjust the vacuum in each sample train to ∼15″
Hg. Use the gas flow meter to determine leak rate. The leakage rate
must not exceed 4 percent of the target sampling rate. Once the
leak check passes this criterion, carefully release the vacuum in
the sample train, then seal the sorbent trap inlet until the probe
is ready for insertion into the stack or duct.
8.1.4 Determination of Flue Gas Characteristics. Determine or
measure the flue gas measurement environment characteristics (gas
temperature, static pressure, gas velocity, stack moisture,
etc.) in order to determine ancillary requirements such as
probe heating requirements (if any), sampling rate, proportional
sampling conditions, moisture management, etc.
8.2 Monitoring.
8.2.1 System Preparation and Initial Data Recording. Remove the
plug from the end of each sorbent trap and store each plug in a
clean sorbent trap storage container. Remove the stack or duct port
cap and insert the probe(s) with the inlet(s) aligned perpendicular
to the stack gas flow. Secure the probe(s) and ensure that no
leakage occurs between the duct and environment. Record initial
data including the sorbent trap ID, start time, starting gas flow
meter readings, initial temperatures, set points, and any other
appropriate information.
8.2.2 Flow Rate Control. Set the initial sample flow rate at the
target value from section 8.1.1 of this performance specification.
Then, for every operating hour during the sampling period, record
the date and time, the sample flow rate, the gas flow meter
reading, the stack temperature (if needed), the flow meter
temperatures (if needed), temperatures of heated equipment such as
the vacuum lines and the probes (if heated), and the sampling
system vacuum readings. Also, record the stack gas flow rate and
the ratio of the stack gas flow rate to the sample flow rate.
Adjust the sampling flow rate to maintain proportional sampling,
i.e., keep the ratio of the stack gas flow rate to sample
flow rate within ±25 percent of the reference ratio from the first
hour of the data collection period (see section 12.2 of this
performance specification). The sample flow rate through a sorbent
trap monitoring system during any hour (or portion of an hour) that
the unit is not operating must be zero.
8.2.3 Stack Gas Moisture Determination. If data from the sorbent
trap monitoring system will be used to calculate Hg mass emissions,
determine the stack gas moisture content using a continuous
moisture monitoring system or other means acceptable to the
Administrator, such as the ones described in § 75.11(b) of this
chapter. Alternatively, for combustion of coal, wood, or natural
gas in boilers only, a default moisture percentage from § 75.11(b)
of this chapter may be used.
8.2.4 Essential Operating Data. Obtain and record any essential
operating data for the facility during the test period, e.g., the
barometric pressure for correcting the sample volume measured by a
dry gas meter to standard conditions. At the end of the data
collection period, record the final gas flow meter reading and the
final values of all other essential parameters.
8.2.5 Post-monitoring Leak Check. When the monitoring period is
completed, turn off the sample pump, remove the probe/sorbent trap
from the port and carefully re-plug the end of each sorbent trap.
Perform a leak check with the sorbent traps in place, at the
maximum vacuum reached during the monitoring period. Use the same
general approach described in section 8.1.3 of this performance
specification. Record the leakage rate and vacuum. The leakage rate
must not exceed 4 percent of the average sampling rate for the
monitoring period. Following the leak check, carefully release the
vacuum in the sample train.
8.2.6 Sample Recovery. Recover each sampled sorbent trap by
removing it from the probe and seal both ends. Wipe any deposited
material from the outside of the sorbent trap. Place the sorbent
trap into an appropriate sample storage container and
store/preserve it in an appropriate manner.
8.2.7 Sample Preservation, Storage, and Transport. While the
performance criteria of this approach provide for verification of
appropriate sample handling, it is still important that the user
consider, determine, and plan for suitable sample preservation,
storage, transport, and holding times for these measurements.
Therefore, procedures in recognized voluntary consensus standards
such as those in ASTM D6911-03 “Standard Guide for Packaging and
Shipping Environmental Samples for Laboratory Analysis” should be
followed for all samples.
8.2.8 Sample Custody. Proper procedures and documentation for
sample chain of custody are critical to ensuring data integrity.
Chain of custody procedures in recognized voluntary consensus
standards such as those in ASTM D4840-99 “Standard Guide for Sample
Chain-of-Custody Procedures” should be followed for all samples
(including field samples and blanks).
8.3 Relative Accuracy (RA) Test Procedure
8.3.1 For the initial certification of a sorbent trap monitoring
system, a RA Test is required. Follow the basic RA test procedures
and calculation methodology described in sections 8.4.1 through
8.4.7 and 12.4 of PS 12A in this appendix, replacing the term
“CEMS” with “sorbent trap monitoring system”.
8.3.2 Special Considerations. The type of sorbent material used
in the traps must be the same as that used for daily operation of
the monitoring system; however, the size of the traps used for the
RA test may be smaller than the traps used for daily operation of
the system. Spike the third section of each sorbent trap with
elemental Hg, as described in section 8.1.2 of this performance
specification. Install a new pair of sorbent traps prior to each
test run. For each run, the sorbent trap data must be validated
according to the quality assurance criteria in Table 12B-1 in
section 9.0, below.
8.3.3 Acceptance Criteria. The RA of the sorbent trap monitoring
system must be no greater than 20 percent of the mean value of the
RM test data in terms of units of µg/scm. Alternatively, if the RM
concentration is less than or equal to 5.0 µg/scm, then the RA
results are acceptable if the absolute difference between the means
of the RM and sorbent trap monitoring system values does not exceed
1.0 µg/scm.
9.0 Quality Assurance and Quality Control (QA/QC)
Table 12B-1 summarizes the QA/QC performance criteria that are
used to validate the Hg emissions data from a sorbent trap
monitoring system. Failure to achieve these performance criteria
will result in invalidation of Hg emissions data, except where
otherwise noted.
Table 12B-1 - QA/QC Criteria for Sorbent
Trap Monitoring Systems
QA/QC test or
specification
Acceptance criteria
Frequency
Consequences if not met
Pre-test leak
check
≤4% of target sampling
rate
Prior to monitoring
Monitoring must not commence
until the leak check is passed.
Post-test leak
check
≤4% of average sampling
rate
After monitoring
Invalidate the data from the
paired traps or, if certain conditions are met, report adjusted
data from a single trap (see Section 12.8.3).
Ratio of stack gas
flow rate to sample flow rate
No more than 5% of the hourly
ratios or 5 hourly ratios (whichever is less restrictive) may
deviate from the reference ratio by more than ±25%
Every hour throughout
monitoring period
Invalidate the data from the
paired traps or, if certain conditions are met, report adjusted
data from a single trap (see Section 12.8.3).
Sorbent trap
section 2 breakthrough
≤5% of Section 1 Hg mass
≤10% of Section 1 Hg mass if average Hg concentration is ≤0.5
µg/scm
Every sample
Invalidate the data from the
paired traps or, if certain conditions are met, report adjusted
data from a single trap (see Section 12.8.3).
No criterion when Hg
concentration for trap less than 10% of the applicable emission
limit (must meet all other QA/QC specifications)
Paired sorbent
trap agreement
≤10% Relative Deviation (RD)
if the average concentration is > 1.0 µg/m 3
≤20% RD if the average concentration is ≤1.0 µg/m 3
Every sample
Either invalidate the data
from the paired traps or report the results from the trap with the
higher Hg concentration.
Results also acceptable if
absolute difference between concentrations from paired traps is ≤
0.03 µg/m 3
Spike Recovery
Study
Average recovery between 85%
and 115% for each of the 3 spike concentration levels
Prior to analyzing field
samples and prior to use of new sorbent media
Field samples must not be
analyzed until the percent recovery criteria have been met.
Multipoint
analyzer calibration
Each analyzer reading within
±10% of true value and r 2 ≥ 0.99
On the day of analysis, before
analyzing any samples
Recalibrate until
successful.
Analysis of
independent calibration standard
Within ±10% of true value
Following daily calibration,
prior to analyzing field samples
Recalibrate and repeat
independent standard analysis until successful.
Spike recovery
from section 3 of both sorbent traps
75-125% of spike amount
Every sample
Invalidate the data from the
paired traps or, if certain conditions are met, report adjusted
data from a single trap (see Section 12.8.3).
Relative
Accuracy
RA ≤ 20.0% of RM mean value;
or if RM mean value ≤5.0 µg/scm, absolute difference between RM and
sorbent trap monitoring system mean values ≤1.0 µg/scm
RA specification must be met
for initial certification
Data from the system are
invalid until a RA test is passed.
Gas flow meter
calibration
An initial calibration factor
(Y) has been determined at 3 settings; for mass flow meters,
initial calibration with stack gas has been performed. For
subsequent calibrations, Y within ±5% of average value from the
most recent 3-point calibration
At 3 settings prior to initial
use and at least quarterly at one setting thereafter
Recalibrate meter at 3
settings to determine a new value of Y.
Temperature sensor
calibration
Absolute temperature measured
by sensor within ±1.5% of a reference sensor
Prior to initial use and at
least quarterly thereafter
Recalibrate; sensor may not be
used until specification is met.
Barometer
calibration
Absolute pressure measured by
instrument within ±10 mm Hg of reading with a NIST-traceable
barometer
Prior to initial use and at
least quarterly thereafter
Recalibrate; instrument may
not be used until specification is met.
10.0 Calibration and Standardization
10.1 Gaseous and Liquid Standards. Only NIST certified or
NIST-traceable calibration standards (i.e., calibration
gases, solutions, etc.) must be used for the spiking and
analytical procedures in this performance specification.
10.2 Gas Flow Meter Calibration. The manufacturer or supplier of
the gas flow meter should perform all necessary set-up, testing,
programming, etc., and should provide the end user with any
necessary instructions, to ensure that the meter will give an
accurate readout of dry gas volume in standard cubic meters for the
particular field application.
10.2.1 Initial Calibration. Prior to its initial use, a
calibration of the flow meter must be performed. The initial
calibration may be done by the manufacturer, by the equipment
supplier, or by the end user. If the flow meter is volumetric in
nature (e.g., a dry gas meter), the manufacturer, equipment
supplier, or end user may perform a direct volumetric calibration
using any gas. For a mass flow meter, the manufacturer, equipment
supplier, or end user may calibrate the meter using a bottled gas
mixture containing 12 ±0.5% CO2, 7 ±0.5% O2, and balance N2, or
these same gases in proportions more representative of the expected
stack gas composition. Mass flow meters may also be initially
calibrated on-site, using actual stack gas.
10.2.1.1 Initial Calibration Procedures. Determine an average
calibration factor (Y) for the gas flow meter, by calibrating it at
three sample flow rate settings covering the range of sample flow
rates at which the sorbent trap monitoring system typically
operates. Either the procedures in section 10.3.1 of Method 5 in
appendix A-3 to this part or the procedures in section 16 of Method
5 in appendix A-3 to this part may be followed. If a dry gas meter
is being calibrated, use at least five revolutions of the meter at
each flow rate.
10.2.1.2 Alternative Initial Calibration Procedures.
Alternatively, the initial calibration of the gas flow meter may be
performed using a reference gas flow meter (RGFM). The RGFM may be
either: (1) A wet test meter calibrated according to section 10.3.1
of Method 5 in appendix A-3 to this part; (2) A gas flow metering
device calibrated at multiple flow rates using the procedures in
section 16 of Method 5 in appendix A-3 to this part; or (3) A
NIST-traceable calibration device capable of measuring volumetric
flow to an accuracy of 1 percent. To calibrate the gas flow meter
using the RGFM, proceed as follows: While the sorbent trap
monitoring system is sampling the actual stack gas or a compressed
gas mixture that simulates the stack gas composition (as
applicable), connect the RGFM to the discharge of the system. Care
should be taken to minimize the dead volume between the sample flow
meter being tested and the RGFM. Concurrently measure dry gas
volume with the RGFM and the flow meter being calibrated for a
minimum of 10 minutes at each of three flow rates covering the
typical range of operation of the sorbent trap monitoring system.
For each 10-minute (or longer) data collection period, record the
total sample volume, in units of dry standard cubic meters (dscm),
measured by the RGFM and the gas flow meter being tested.
10.2.1.3 Initial Calibration Factor. Calculate an individual
calibration factor Yi at each tested flow rate from section
10.2.1.1 or 10.2.1.2 of this performance specification (as
applicable), by taking the ratio of the reference sample volume to
the sample volume recorded by the gas flow meter. Average the three
Yi values, to determine Y, the calibration factor for the flow
meter. Each of the three individual values of Yi must be within
±0.02 of Y. Except as otherwise provided in sections 10.2.1.4 and
10.2.1.5 of this performance specification, use the average Y value
from the three level calibration to adjust all subsequent gas
volume measurements made with the gas flow meter.
10.2.2 Initial On-Site Calibration Check. For a mass flow meter
that was initially calibrated using a compressed gas mixture, an
on-site calibration check must be performed before using the flow
meter to provide data. While sampling stack gas, check the
calibration of the flow meter at one intermediate flow rate typical
of normal operation of the monitoring system. Follow the basic
procedures in section 10.2.1.1 or 10.2.1.2 of this performance
specification. If the onsite calibration check shows that the value
of Yi, the calibration factor at the tested flow rate, differs by
more than 5 percent from the value of Y obtained in the initial
calibration of the meter, repeat the full 3-level calibration of
the meter using stack gas to determine a new value of Y, and apply
the new Y value to all subsequent gas volume measurements made with
the gas flow meter.
10.2.3 Ongoing Quality Control. Recalibrate the gas flow meter
quarterly at one intermediate flow rate setting representative of
normal operation of the monitoring system. Follow the basic
procedures in section 10.2.1.1 or 10.2.1.2 of this performance
specification. If a quarterly recalibration shows that the value of
Yi, the calibration factor at the tested flow rate, differs from
the current value of Y by more than 5 percent, repeat the full
3-level calibration of the meter to determine a new value of Y, and
apply the new Y value to all subsequent gas volume measurements
made with the gas flow meter.
10.3 Calibration of Thermocouples and Other Temperature Sensors.
Use the procedures and criteria in section 10.3 of Method 2 in
appendix A-1 to this part to calibrate in-stack temperature sensors
and thermocouples. Calibrations must be performed prior to initial
use and at least quarterly thereafter. At each calibration point,
the absolute temperature measured by the temperature sensor must
agree to within ±1.5 percent of the temperature measured with the
reference sensor, otherwise the sensor may not continue to be
used.
10.4 Barometer Calibration. Calibrate the barometer against
another barometer that has a NIST-traceable calibration. This
calibration must be performed prior to initial use and at least
quarterly thereafter. At each calibration point, the absolute
pressure measured by the barometer must agree to within ±10 mm Hg
of the pressure measured by the NIST-traceable barometer, otherwise
the barometer may not continue to be used.
10.5 Calibration of Other Sensors and Gauges. Calibrate all
other sensors and gauges according to the procedures specified by
the instrument manufacturer(s).
10.6 Analytical System Calibration. See section 11.1 of
this performance specification.
11.0 Analytical Procedures
The analysis of the Hg samples may be conducted using any
instrument or technology capable of quantifying total Hg from the
sorbent media and meeting the performance criteria in section 9 of
this performance specification.
11.1 Analyzer System Calibration. Perform a multipoint
calibration of the analyzer at three or more upscale points over
the desired quantitative range (multiple calibration ranges must be
calibrated, if necessary). The field samples analyzed must fall
within a calibrated, quantitative range and meet the necessary
performance criteria. For samples that are suitable for
aliquotting, a series of dilutions may be needed to ensure that the
samples fall within a calibrated range. However, for sorbent media
samples that are consumed during analysis (e.g., thermal desorption
techniques), extra care must be taken to ensure that the analytical
system is appropriately calibrated prior to sample analysis. The
calibration curve range(s) should be determined based on the
anticipated level of Hg mass on the sorbent media. Knowledge of
estimated stack Hg concentrations and total sample volume may be
required prior to analysis. The calibration curve for use with the
various analytical techniques (e.g., UV AA, UV AF, and XRF) can be
generated by directly introducing standard solutions into the
analyzer or by spiking the standards onto the sorbent media and
then introducing into the analyzer after preparing the
sorbent/standard according to the particular analytical technique.
For each calibration curve, the value of the square of the linear
correlation coefficient, i.e., r 2, must be ≥0.99, and the
analyzer response must be within ±10 percent of reference value at
each upscale calibration point. Calibrations must be performed on
the day of the analysis, before analyzing any of the samples.
Following calibration, an independently prepared standard (not from
same calibration stock solution) must be analyzed. The measured
value of the independently prepared standard must be within ±10
percent of the expected value.
11.2 Sample Preparation. Carefully separate the three sections
of each sorbent trap. Combine for analysis all materials associated
with each section, i.e., any supporting substrate that the
sample gas passes through prior to entering a media section (e.g.,
glass wool, polyurethane foam, etc.) must be analyzed with
that segment.
11.3 Spike Recovery Study. Before analyzing any field samples,
the laboratory must demonstrate the ability to recover and quantify
Hg from the sorbent media by performing the following spike
recovery study for sorbent media traps spiked with elemental
mercury. Using the procedures described in sections 6.2 and 12.1 of
this performance specification, spike the third section of nine
sorbent traps with gaseous Hg 0, i.e., three traps at each
of three different mass loadings, representing the range of masses
anticipated in the field samples. This will yield a 3 × 3 sample
matrix. Prepare and analyze the third section of each spiked trap,
using the techniques that will be used to prepare and analyze the
field samples. The average recovery for each spike concentration
must be between 85 and 115 percent. If multiple types of sorbent
media are to be analyzed, a separate spike recovery study is
required for each sorbent material. If multiple ranges are
calibrated, a separate spike recovery study is required for each
range.
11.4 Field Sample Analyses. Analyze the sorbent trap samples
following the same procedures that were used for conducting the
spike recovery study. The three sections of each sorbent trap must
be analyzed separately (i.e., section 1, then section 2,
then section 3). Quantify the total mass of Hg for each section
based on analytical system response and the calibration curve from
section 11.1 of this performance specification. Determine the spike
recovery from sorbent trap section 3. The spike recovery must be no
less than 75 percent and no greater than 125 percent. To report the
final Hg mass for each trap, add together the Hg masses collected
in trap sections 1 and 2.
12.0 Calculations, Data Reduction, and Data Analysis
12.1 Calculation of Pre-Sampling Spiking Level. Determine
sorbent trap section 3 spiking level using estimates of the stack
Hg concentration, the target sample flow rate, and the expected
monitoring period. Calculate Mexp, the expected Hg mass that will
be collected in section 1 of the trap, using Equation 12B-1. The
pre-sampling spike must be within ±50 percent of this mass.
Where: Mexp = Expected sample mass (µg) Qs =
Sample flow rate (L/min) ts = Expected monitoring period (min) Cest
= Estimated Hg concentration in stack gas (µg/m 3) 10−3 =
Conversion factor (m 3/L) Example calculation:For an estimated
stack Hg concentration of 5 µg/m 3, a target sample rate of 0.30
L/min, and a monitoring period of 5 days: Mexp = (0.30 L/min)(1440
min/day)(5 days)(10−3 m 3/L)(5 µg/m 3) = 10.8 µg
A pre-sampling spike of 10.8 µg ±50 percent is, therefore,
appropriate.
12.2 Calculations for Flow-Proportional Sampling. For the first
hour of the data collection period, determine the reference ratio
of the stack gas volumetric flow rate to the sample flow rate, as
follows:
Where: Rref = Reference ratio of hourly stack
gas flow rate to hourly sample flow rate Qref = Average stack gas
volumetric flow rate for first hour of collection period (scfh)
Fref = Average sample flow rate for first hour of the collection
period, in appropriate units (e.g., liters/min, cc/min, dscm/min) K
= Power of ten multiplier, to keep the value of Rref between 1 and
100. The appropriate K value will depend on the selected units of
measure for the sample flow rate.
Then, for each subsequent hour of the data collection period,
calculate ratio of the stack gas flow rate to the sample flow rate
using Equation 12B-3:
Where: Rh = Ratio of hourly stack gas flow rate
to hourly sample flow rate Qh = Average stack gas volumetric flow
rate for the hour (scfh) Fh = Average sample flow rate for the
hour, in appropriate units (e.g., liters/min, cc/min, dscm/min) K =
Power of ten multiplier, to keep the value of Rh between 1 and 100.
The appropriate K value will depend on the selected units of
measure for the sample flow rate and the range of expected stack
gas flow rates.
Maintain the value of Rh within ±25 percent of Rref throughout
the data collection period.
12.3 Calculation of Spike Recovery. Calculate the percent
recovery of each section 3 spike, as follows:
Where: %R = Percentage recovery of the
pre-sampling spike M3 = Mass of Hg recovered from section 3 of the
sorbent trap, (µg) Ms = Calculated Hg mass of the pre-sampling
spike, from section 8.1.2 of this performance specification, (µg)
12.4 Calculation of Breakthrough. Calculate the percent
breakthrough to the second section of the sorbent trap, as
follows:
Where: %B = Percent breakthrough M2 = Mass of
Hg recovered from section 2 of the sorbent trap, (µg) M1 = Mass of
Hg recovered from section 1 of the sorbent trap, (µg)
12.5 Calculation of Hg Concentration. Calculate the Hg
concentration for each sorbent trap, using the following
equation:
Where: C = Concentration of Hg for the
collection period, (µg/dscm) M* = Total mass of Hg recovered from
sections 1 and 2 of the sorbent trap, (µg) Vt = Total volume of dry
gas metered during the collection period, (dscm). For the purposes
of this performance specification, standard temperature and
pressure are defined as 20 °C and 760 mm Hg, respectively.
12.6 Calculation of Paired Trap Agreement. Calculate the
relative deviation (RD) between the Hg concentrations measured with
the paired sorbent traps:
Where: RD = Relative deviation between the Hg
concentrations from traps “a” and “b” (percent) Ca = Concentration
of Hg for the collection period, for sorbent trap “a” (µg/dscm) Cb
= Concentration of Hg for the collection period, for sorbent trap
“b” (µg/dscm)
12.7 Calculation of Relative Accuracy. Calculate the relative
accuracy as described in section 12.4 of PS 12A in this
appendix.
12.8 Data Reduction. Typical monitoring periods for normal,
day-to-day operation of a sorbent trap monitoring system range from
about 24 hours to 168 hours. For the required RA tests of the
system, smaller sorbent traps are often used, and the “monitoring
period” or time per run is considerably shorter (e.g., 1 hour or
less). Generally speaking, to validate sorbent trap monitoring
system data, the acceptance criteria for the following five QC
specifications in Table 12B-1 above must be met for both traps: (a)
the post-monitoring leak check; (b) the ratio of stack gas flow
rate to sample flow rate; (c) section 2 breakthrough; (d) paired
trap agreement; and (e) section 3 spike recovery.
12.8.1 For routine day-to-day operation of a sorbent trap
monitoring system, when both traps meet the acceptance criteria for
all five QC specifications, the two measured Hg concentrations must
be averaged arithmetically and the average value must be applied to
each hour of the data collection period.
12.8.2 To validate a RA test run, both traps must meet the
acceptance criteria for all five QC specifications. However, as
specified in section 12.8.3 below, for routine day-to-day operation
of the monitoring system, a monitoring period may, in certain
instances, be validated based on the results from one trap.
12.8.3 For the routine, day-to-day operation of the monitoring
system, when one of the two sorbent trap samples or sampling
systems either: (a) Fails the post-monitoring leak check; or (b)
has excessive section 2 breakthrough; or (c) fails to maintain the
proper stack flow-to-sample flow ratio; or (d) fails to achieve the
required section 3 spike recovery; or (e) is lost, broken, or
damaged, provided that the other trap meets the acceptance criteria
for all four of these QC specifications, the Hg concentration
measured by the valid trap may be multiplied by a factor of 1.111
and then used for reporting purposes. Further, if both traps meet
the acceptance criteria for all four of these QC specifications,
but the acceptance criterion for paired trap agreement is not met,
the owner or operator may report the higher of the two Hg
concentrations measured by the traps, in lieu of invalidating the
data from the paired traps.
12.8.4 Whenever the data from a pair of sorbent traps must be
invalidated and no quality-assured data from a certified backup Hg
monitoring system or Hg reference method are available to cover the
hours in the data collection period, treat those hours in the
manner specified in the applicable regulation (i.e., use
missing data substitution procedures or count the hours as
monitoring system down time, as appropriate).
13.0 Monitoring System Performance
These monitoring criteria and procedures have been successfully
applied to coal-fired utility boilers (including units with
post-combustion emission controls), having vapor-phase Hg
concentrations ranging from 0.03 µg/dscm to approximately 100
µg/dscm.
17.1 40 CFR Part 60, Appendix B, “Performance Specification 2 -
Specifications and Test Procedures for SO2 and NOX Continuous
Emission Monitoring Systems in Stationary Sources.”
17.2 40 CFR Part 60, Appendix B, “Performance Specification 12A
- Specifications and Test Procedures for Total Vapor Phase Mercury
Continuous Emission Monitoring Systems in Stationary Sources.”
Performance Specification 15 - Performance Specification for
Extractive FTIR Continuous Emissions Monitor Systems in Stationary
Sources 1.0 Scope and Application
1.1 Analytes. This performance specification is applicable for
measuring all hazardous air pollutants (HAPs) which absorb in the
infrared region and can be quantified using Fourier Transform
Infrared Spectroscopy (FTIR), as long as the performance criteria
of this performance specification are met. This specification is to
be used for evaluating FTIR continuous emission monitoring systems
for measuring HAPs regulated under Title III of the 1990 Clean Air
Act Amendments. This specification also applies to the use of FTIR
CEMs for measuring other volatile organic or inorganic species.
1.2 Applicability. A source which can demonstrate that the
extractive FTIR system meets the criteria of this performance
specification for each regulated pollutant may use the FTIR system
to continuously monitor for the regulated pollutants.
2.0 Summary of Performance Specification
For compound-specific sampling requirements refer to FTIR
sampling methods (e.g., reference 1). For data reduction
procedures and requirements refer to the EPA FTIR Protocol
(reference 2), hereafter referred to as the “FTIR Protocol.” This
specification describes sampling and analytical procedures for
quality assurance. The infrared spectrum of any absorbing compound
provides a distinct signature. The infrared spectrum of a mixture
contains the superimposed spectra of each mixture component. Thus,
an FTIR CEM provides the capability to continuously measure
multiple components in a sample using a single analyzer. The number
of compounds that can be speciated in a single spectrum depends, in
practice, on the specific compounds present and the test
conditions.
3.0 Definitions
For a list of definitions related to FTIR spectroscopy refer to
Appendix A of the FTIR Protocol. Unless otherwise specified,
spectroscopic terms, symbols and equations in this performance
specification are taken from the FTIR Protocol or from documents
cited in the Protocol. Additional definitions are given below.
3.1 FTIR Continuous Emission Monitoring System (FTIR CEM).
3.1.1 FTIR System. Instrument to measure spectra in the
mid-infrared spectral region (500 to 4000 cm−1). It contains an
infrared source, interferometer, sample gas containment cell,
infrared detector, and computer. The interferometer consists of a
beam splitter that divides the beam into two paths, one path a
fixed distance and the other a variable distance. The computer is
equipped with software to run the interferometer and store the raw
digitized signal from the detector (interferogram). The software
performs the mathematical conversion (the Fourier transform) of the
interferogram into a spectrum showing the frequency dependent
sample absorbance. All spectral data can be stored on computer
media.
3.1.2 Gas Cell. A gas containment cell that can be
evacuated. It contains the sample as the infrared beam passes from
the interferometer, through the sample, and to the detector. The
gas cell may have multi-pass mirrors depending on the required
detection limit(s) for the application.
3.1.3 Sampling System. Equipment used to extract sample
from the test location and transport the gas to the FTIR analyzer.
Sampling system components include probe, heated line, heated
non-reactive pump, gas distribution manifold and valves, flow
measurement devices and any sample conditioning systems.
3.2 Reference CEM. An FTIR CEM, with sampling system,
that can be used for comparison measurements.
3.3 Infrared Band (also Absorbance Band or Band).
Collection of lines arising from rotational transitions
superimposed on a vibrational transition. An infrared absorbance
band is analyzed to determine the analyte concentration.
3.4 Sample Analysis. Interpreting infrared band shapes,
frequencies, and intensities to obtain sample component
concentrations. This is usually performed by a software routine
using a classical least squares (cls), partial least squares (pls),
or K- or P- matrix method.
3.5 (Target) Analyte. A compound whose measurement is
required, usually to some established limit of detection and
analytical uncertainty.
3.6 Interferant. A compound in the sample matrix whose
infrared spectrum overlaps at least part of an analyte spectrum
complicating the analyte measurement. The interferant may not
prevent the analyte measurement, but could increase the analytical
uncertainty in the measured concentration. Reference spectra of
interferants are used to distinguish the interferant bands from the
analyte bands. An interferant for one analyte may not be an
interferant for other analytes.
3.7 Reference Spectrum. Infrared spectra of an analyte,
or interferant, prepared under controlled, documented, and
reproducible laboratory conditions (see section 4.6 of the FTIR
Protocol). A suitable library of reference spectra can be used to
measure target analytes in gas samples.
3.8 Calibration Spectrum. Infrared spectrum of a compound
suitable for characterizing the FTIR instrument configuration
(Section 4.5 in the FTIR Protocol).
3.9 One hundred percent line. A double beam transmittance
spectrum obtained by combining two successive background single
beam spectra. Ideally, this line is equal to 100 percent
transmittance (or zero absorbance) at every point in the spectrum.
The zero absorbance line is used to measure the RMS noise of the
system.
3.10 Background Deviation. Any deviation (from 100
percent) in the one hundred percent line (or from zero absorbance).
Deviations greater than ±5 percent in any analytical region are
unacceptable. Such deviations indicate a change in the instrument
throughput relative to the single-beam background.
3.11 Batch Sampling. A gas cell is alternately filled and
evacuated. A Spectrum of each filled cell (one discreet sample) is
collected and saved.
3.12 Continuous Sampling. Sample is continuously flowing
through a gas cell. Spectra of the flowing sample are collected at
regular intervals.
3.13 Continuous Operation. In continuous operation an
FTIR CEM system, without user intervention, samples flue gas,
records spectra of samples, saves the spectra to a disk, analyzes
the spectra for the target analytes, and prints concentrations of
target analytes to a computer file. User intervention is permitted
for initial set-up of sampling system, initial calibrations, and
periodic maintenance.
3.14 Sampling Time. In batch sampling - the time required
to fill the cell with flue gas. In continuous sampling - the time
required to collect the infrared spectrum of the sample gas.
3.15 PPM-Meters. Sample concentration expressed as the
concentration-path length product, ppm (molar) concentration
multiplied by the path length of the FTIR gas cell. Expressing
concentration in these units provides a way to directly compare
measurements made using systems with different optical
configurations. Another useful expression is (ppm-meters)/K, where
K is the absolute temperature of the sample in the gas cell.
3.16 CEM Measurement Time Constant. The Time Constant
(TC, minutes for one cell volume to flow through the cell)
determines the minimum interval for complete removal of an analyte
from the FTIR cell. It depends on the sampling rate (Rs in Lpm),
the FTIR cell volume (Vcell in L) and the chemical and physical
properties of an analyte.
For example, if the sample flow rate (through
the FTIR cell) is 5 Lpm and the cell volume is 7 liters, then TC is
equal to 1.4 minutes (0.71 cell volumes per minute). This
performance specification defines 5 * TC as the minimum interval
between independent samples.
3.17 Independent Measurement. Two independent
measurements are spectra of two independent samples. Two
independent samples are separated by, at least 5 cell volumes. The
interval between independent measurements depends on the cell
volume and the sample flow rate (through the cell). There is no
mixing of gas between two independent samples. Alternatively,
estimate the analyte residence time empirically: (1) Fill cell to
ambient pressure with a (known analyte concentration) gas standard,
(2) measure the spectrum of the gas standard, (3) purge the cell
with zero gas at the sampling rate and collect a spectrum every
minute until the analyte standard is no longer detected
spectroscopically. If the measured time corresponds to less than 5
cell volumes, use 5 * TC as the minimum interval between
independent measurements. If the measured time is greater than 5 *
TC, then use this time as the minimum interval between independent
measurements.
3.18 Test Condition. A period of sampling where all
process, and sampling conditions, and emissions remain constant and
during which a single sampling technique and a single analytical
program are used. One Run may include results for more than one
test condition. Constant emissions means that the composition of
the emissions remains approximately stable so that a single
analytical program is suitable for analyzing all of the sample
spectra. A greater than two-fold change in analyte or interferant
concentrations or the appearance of additional compounds in the
emissions, may constitute a new test condition and may require
modification of the analytical program.
3.19 Run. A single Run consists of spectra (one spectrum
each) of at least 10 independent samples over a minimum of one
hour. The concentration results from the spectra can be averaged
together to give a run average for each analyte measured in the
test run.
4.0 Interferences
Several compounds, including water, carbon monoxide, and carbon
dioxide, are known interferences in the infrared region in which
the FTIR instrument operates. Follow the procedures in the FTIR
protocol for subtracting or otherwise dealing with these and other
interferences.
5.0 Safety
The procedures required under this performance specification may
involve hazardous materials, operations, and equipment. This
performance specification may not address all of the safety
problems associated with these procedures. It is the responsibility
of the user to establish appropriate safety and health practices
and determine the applicable regulatory limitations prior to
performing these procedures. The CEMS users manual and materials
recommended by this performance specification should be consulted
for specific precautions to be taken.
6.0 Equipment and Supplies
6.1 Installation of sampling equipment should follow
requirements of FTIR test Methods such as references 1 and 3 and
the EPA FTIR Protocol (reference 2). Select test points where the
gas stream composition is representative of the process emissions.
If comparing to a reference method, the probe tips for the FTIR CEM
and the RM should be positioned close together using the same
sample port if possible.
6.2 FTIR Specifications. The FTIR CEM must be equipped with
reference spectra bracketing the range of path
length-concentrations (absorbance intensities) to be measured for
each analyte. The effective concentration range of the analyzer can
be adjusted by changing the path length of the gas cell or by
diluting the sample. The optical configuration of the FTIR system
must be such that maximum absorbance of any target analyte is no
greater than 1.0 and the minimum absorbance of any target analyte
is at least 10 times the RMSD noise in the analytical region. For
example, if the measured RMSD in an analytical region is equal to
10−3, then the peak analyte absorbance is required to be at least
0.01. Adequate measurement of all of the target analytes may
require changing path lengths during a run, conducting separate
runs for different analytes, diluting the sample, or using more
than one gas cell.
6.3 Data Storage Requirements. The system must have sufficient
capacity to store all data collected in one week of routine
sampling. Data must be stored to a write-protected medium, such as
write-once-read-many (WORM) optical storage medium or to a password
protected remote storage location. A back-up copy of all data can
be temporarily saved to the computer hard drive. The following
items must be stored during testing.
• At least one sample interferogram per sampling Run or one
interferogram per hour, whichever is greater. This assumes that no
sampling or analytical conditions have changed during the run.
• All sample absorbance spectra (about 12 per hr, 288 per
day).
• All background spectra and interferograms (variable, but about
5 per day).
• All CTS spectra and interferograms (at least 2 each 24 hour
period).
• Documentation showing a record of resolution, path length,
apodization, sampling time, sampling conditions, and test
conditions for all sample, CTS, calibration, and background
spectra.
Using a resolution of 0.5 cm−1, with analytical range of 3500
cm−1, assuming about 65 Kbytes per spectrum and 130 Kb per
interferogram, the storage requirement is about 164 Mb for one week
of continuous sampling. Lower spectral resolution requires less
storage capacity. All of the above data must be stored for at least
two weeks. After two weeks, storage requirements include: (1) all
analytical results (calculated concentrations), (2) at least 1
sample spectrum with corresponding background and sample
interferograms for each test condition, (3) CTS and calibration
spectra with at least one interferogram for CTS and all
interferograms for calibrations, (4) a record of analytical input
used to produce results, and (5) all other documentation. These
data must be stored according to the requirements of the applicable
regulation.
7.0 Reagents and Standards [Reserved] 8.0 Sample Collection,
Preservation, Storage, and Transport [Reserved] 9.0 Quality Control
These procedures shall be used for periodic quarterly or
semiannual QA/QC checks on the operation of the FTIR CEM. Some
procedures test only the analytical program and are not intended as
a test of the sampling system.
9.1 Audit Sample. This can serve as a check on both the sampling
system and the analytical program.
9.1.1 Sample Requirements. The audit sample can be a mixture or
a single component. It must contain target analyte(s) at
approximately the expected flue gas concentration(s). If possible,
each mixture component concentration should be NIST traceable (±2
percent accuracy). If a cylinder mixture standard(s) cannot be
obtained, then, alternatively, a gas phase standard can be
generated from a condensed phase analyte sample. Audit sample
contents and concentrations are not revealed to the FTIR CEM
operator until after successful completion of procedures in
5.3.2.
9.1.2 Test Procedure. Spike the audit sample using the analyte
spike procedure in section 11. The audit sample is measured
directly by the FTIR system (undiluted) and then spiked into the
effluent at a known dilution ratio. Measure a series of spiked and
unspiked samples using the same procedures as those used to analyze
the stack gas. Analyze the results using sections 12.1 and 12.2.
The measured concentration of each analyte must be within ±5
percent of the expected concentration (plus the uncertainty),
i.e., the calculated correction factor must be within 0.93
and 1.07 for an audit with an analyte uncertainty of ±2
percent.
9.2 Audit Spectra. Audit spectra can be used to test the
analytical program of the FTIR CEM, but provide no test of the
sampling system.
9.2.1 Definition and Requirements. Audit spectra are absorbance
spectra that; (1) have been well characterized, and (2) contain
absorbance bands of target analyte(s) and potential interferants at
intensities equivalent to what is expected in the source effluent.
Audit spectra are provided by the administrator without identifying
information. Methods of preparing Audit spectra include; (1)
mathematically adding sample spectra or adding reference and
interferant spectra, (2) obtaining sample spectra of mixtures
prepared in the laboratory, or (3) they may be sample spectra
collected previously at a similar source. In the last case it must
be demonstrated that the analytical results are correct and
reproducible. A record associated with each Audit spectrum
documents its method of preparation. The documentation must be
sufficient to enable an independent analyst to reproduce the Audit
spectra.
9.2.2 Test Procedure. Audit spectra concentrations are measured
using the FTIR CEM analytical program. Analytical results must be
within ±5 percent of the certified audit concentration for each
analyte (plus the uncertainty in the audit concentration). If the
condition is not met, demonstrate how the audit spectra are
unrepresentative of the sample spectra. If the audit spectra are
representative, modify the FTIR CEM analytical program until the
test requirement is met. Use the new analytical program in
subsequent FTIR CEM analyses of effluent samples.
9.3 Submit Spectra For Independent Analysis. This procedure
tests only the analytical program and not the FTIR CEM sampling
system. The analyst can submit FTIR CEM spectra for independent
analysis by EPA. Requirements for submission include; (1) three
representative absorbance spectra (and stored interferograms) for
each test period to be reviewed, (2) corresponding CTS spectra, (3)
corresponding background spectra and interferograms, (4) spectra of
associated spiked samples if applicable, and (5) analytical results
for these sample spectra. The analyst will also submit
documentation of process times and conditions, sampling conditions
associated with each spectrum, file names and sampling times,
method of analysis and reference spectra used, optical
configuration of FTIR CEM including cell path length and
temperature, spectral resolution and apodization used for every
spectrum. Independent analysis can also be performed on site in
conjunction with the FTIR CEM sampling and analysis. Sample spectra
are stored on the independent analytical system as they are
collected by the FTIR CEM system. The FTIR CEM and the independent
analyses are then performed separately. The two analyses will agree
to within ±120 percent for each analyte using the procedure in
section 12.3. This assumes both analytical routines have properly
accounted for differences in optical path length, resolution, and
temperature between the sample spectra and the reference
spectra.
10.0 Calibration and Standardization
10.1 Calibration Transfer Standards. For CTS requirements see
section 4.5 of the FTIR Protocol. A well characterized absorbance
band in the CTS gas is used to measure the path length and line
resolution of the instrument. The CTS measurements made at the
beginning of every 24 hour period must agree to within ±5 percent
after correction for differences in pressure.
Verify that the frequency response of the instrument and CTS
absorbance intensity are correct by comparing to other CTS spectra
or by referring to the literature.
10.2 Analyte Calibration. If EPA library reference spectra are
not available, use calibration standards to prepare reference
spectra according to section 6 of the FTIR Protocol. A suitable set
of analyte reference data includes spectra of at least 2
independent samples at each of at least 2 different concentrations.
The concentrations bracket a range that includes the expected
analyte absorbance intensities. The linear fit of the reference
analyte band areas must have a fractional calibration uncertainty
(FCU in Appendix F of the FTIR Protocol) of no greater than 10
percent. For requirements of analyte standards refer to section 4.6
of the FTIR Protocol.
10.3 System Calibration. The calibration standard is introduced
at a point on the sampling probe. The sampling system is purged
with the calibration standard to verify that the absorbance
measured in this way is equal to the absorbance in the analyte
calibration. Note that the system calibration gives no indication
of the ability of the sampling system to transport the target
analyte(s) under the test conditions.
10.4 Analyte Spike. The target analyte(s) is spiked at the
outlet of the sampling probe, upstream of the particulate filter,
and combined with effluent at a ratio of about 1 part spike to 9
parts effluent. The measured absorbance of the spike is compared to
the expected absorbance of the spike plus the analyte concentration
already in the effluent. This measures sampling system bias, if
any, as distinguished from analyzer bias. It is important that
spiked sample pass through all of the sampling system components
before analysis.
10.5 Signal-to-Noise Ratio (S/N). The measure of S/N in this
performance specification is the root-mean-square (RMS) noise level
as given in Appendix C of the FTIR Protocol. The RMS noise level of
a contiguous segment of a spectrum is defined as the RMS difference
(RMSD) between the n contiguous absorbance values (Ai) which form
the segment and the mean value (AM) of that segment.
A decrease in the S/N may indicate a loss in
optical throughput, or detector or interferometer malfunction.
10.6 Background Deviation. The 100 percent baseline must be
between 95 and 105 percent transmittance (absorbance of 0.02 to
−0.02) in every analytical region. When background deviation
exceeds this range, a new background spectrum must be collected
using nitrogen or other zero gas.
10.7 Detector Linearity. Measure the background and CTS at three
instrument aperture settings; one at the aperture setting to be
used in the testing, and one each at settings one half and twice
the test aperture setting. Compare the three CTS spectra. CTS band
areas should agree to within the uncertainty of the cylinder
standard. If test aperture is the maximum aperture, collect CTS
spectrum at maximum aperture, then close the aperture to reduce the
IR through-put by half. Collect a second background and CTS at the
smaller aperture setting and compare the spectra as above. Instead
of changing the aperture neutral density filters can be used to
attenuate the infrared beam. Set up the FTIR system as it will be
used in the test measurements. Collect a CTS spectrum. Use a
neutral density filter to attenuate the infrared beam (either
immediately after the source or the interferometer) to
approximately 1/2 its original intensity. Collect a second CTS
spectrum. Use another filter to attenuate the infrared beam to
approximately 1/4 its original intensity. Collect a third
background and CTS spectrum. Compare the CTS spectra as above.
Another check on linearity is to observe the single beam background
in frequency regions where the optical configuration is known to
have a zero response. Verify that the detector response is “flat”
and equal to zero in these regions. If detector response is not
linear, decrease aperture, or attenuate the infrared beam. Repeat
the linearity check until system passes the requirement.
11.0 Analytical Procedure
11.1 Initial Certification. First, perform the evaluation
procedures in section 6.0 of the FTIR Protocol. The performance of
an FTIR CEM can be certified upon installation using EPA Method 301
type validation (40 CFR, Part 63, Appendix A), or by comparison to
a reference Method if one exists for the target analyte(s). Details
of each procedure are given below. Validation testing is used for
initial certification upon installation of a new system. Subsequent
performance checks can be performed with more limited analyte
spiking. Performance of the analytical program is checked
initially, and periodically as required by EPA, by analyzing audit
spectra or audit gases.
11.1.1 Validation. Use EPA Method 301 type sampling (reference
4, section 5.3 of Method 301) to validate the FTIR CEM for
measuring the target analytes. The analyte spike procedure is as
follows: (1) a known concentration of analyte is mixed with a known
concentration of a non-reactive tracer gas, (2) the undiluted spike
gas is sent directly to the FTIR cell and a spectrum of this sample
is collected, (3) pre-heat the spiked gas to at least the sample
line temperature, (4) introduce spike gas at the back of the sample
probe upstream of the particulate filter, (5) spiked effluent is
carried through all sampling components downstream of the probe,
(6) spike at a ratio of roughly 1 part spike to 9 parts flue gas
(or more dilute), (7) the spike-to-flue gas ratio is estimated by
comparing the spike flow to the total sample flow, and (8) the
spike ratio is verified by comparing the tracer concentration in
spiked flue gas to the tracer concentration in undiluted spike gas.
The analyte flue gas concentration is unimportant as long as the
spiked component can be measured and the sample matrix (including
interferences) is similar to its composition under test conditions.
Validation can be performed using a single FTIR CEM analyzing
sample spectra collected sequentially. Since flue gas analyte
(unspiked) concentrations can vary, it is recommended that two
separate sampling lines (and pumps) are used; one line to carry
unspiked flue gas and the other line to carry spiked flue gas. Even
with two sampling lines the variation in unspiked concentration may
be fast compared to the interval between consecutive measurements.
Alternatively, two FTIR CEMs can be operated side-by-side, one
measuring spiked sample, the other unspiked sample. In this
arrangement spiked and unspiked measurements can be synchronized to
minimize the affect of temporal variation in the unspiked analyte
concentration. In either sampling arrangement, the interval between
measured concentrations used in the statistical analysis should be,
at least, 5 cell volumes (5 * TC in equation 1). A validation run
consists of, at least, 24 independent analytical results, 12 spiked
and 12 unspiked samples. See section 3.17 for definition of an
“independent” analytical result. The results are analyzed using
sections 12.1 and 12.2 to determine if the measurements passed the
validation requirements. Several analytes can be spiked and
measured in the same sampling run, but a separate statistical
analysis is performed for each analyte. In lieu of 24 independent
measurements, averaged results can be used in the statistical
analysis. In this procedure, a series of consecutive spiked
measurements are combined over a sampling period to give a single
average result. The related unspiked measurements are averaged in
the same way. The minimum 12 spiked and 12 unspiked result averages
are obtained by averaging measurements over subsequent sampling
periods of equal duration. The averaged results are grouped
together and statistically analyzed using section 12.2.
11.1.1.1 Validation with a Single Analyzer and Sampling Line. If
one sampling line is used, connect the sampling system components
and purge the entire sampling system and cell with at least 10 cell
volumes of sample gas. Begin sampling by collecting spectra of 2
independent unspiked samples. Introduce the spike gas into the back
of the probe, upstream of the particulate filter. Allow 10 cell
volumes of spiked flue gas to purge the cell and sampling system.
Collect spectra of 2 independent spiked samples. Turn off the spike
flow and allow 10 cell volumes of unspiked flue gas to purge the
FTIR cell and sampling system. Repeat this procedure 6 times until
the 24 samples are collected. Spiked and unspiked samples can also
be measured in groups of 4 instead of in pairs. Analyze the results
using sections 12.1 and 12.2. If the statistical analysis passes
the validation criteria, then the validation is completed. If the
results do not pass the validation, the cause may be that temporal
variations in the analyte sample gas concentration are fast
relative to the interval between measurements. The difficulty may
be avoided by: (1) Averaging the measurements over long sampling
periods and using the averaged results in the statistical analysis,
(2) modifying the sampling system to reduce TC by, for example,
using a smaller volume cell or increasing the sample flow rate, (3)
using two sample lines (4) use two analyzers to perform
synchronized measurements. This performance specification permits
modifications in the sampling system to minimize TC if the other
requirements of the validation sampling procedure are met.
11.1.1.2 Validation With a Single Analyzer and Two Sampling
Lines. An alternative sampling procedure uses two separate sample
lines, one carrying spiked flue gas, the other carrying unspiked
gas. A valve in the gas distribution manifold allows the operator
to choose either sample. A short heated line connects the FTIR cell
to the 3-way valve in the manifold. Both sampling lines are
continuously purged. Each sample line has a rotameter and a bypass
vent line after the rotameter, immediately upstream of the valve,
so that the spike and unspiked sample flows can each be
continuously monitored. Begin sampling by collecting spectra of 2
independent unspiked samples. Turn the sampling valve to close off
the unspiked gas flow and allow the spiked flue gas to enter the
FTIR cell. Isolate and evacuate the cell and fill with the spiked
sample to ambient pressure. (While the evacuated cell is filling,
prevent air leaks into the cell by making sure that the spike
sample rotameter always indicates that a portion of the flow is
directed out the by-pass vent.) Open the cell outlet valve to allow
spiked sample to continuously flow through the cell. Measure
spectra of 2 independent spiked samples. Repeat this procedure
until at least 24 samples are collected.
11.1.1.3 Synchronized Measurements With Two Analyzers. Use two
FTIR analyzers, each with its own cell, to perform synchronized
spiked and unspiked measurements. If possible, use a similar
optical configuration for both systems. The optical configurations
are compared by measuring the same CTS gas with both analyzers.
Each FTIR system uses its own sampling system including a separate
sampling probe and sampling line. A common gas distribution
manifold can be used if the samples are never mixed. One sampling
system and analyzer measures spiked effluent. The other sampling
system and analyzer measures unspiked flue gas. The two systems are
synchronized so that each measures spectra at approximately the
same times. The sample flow rates are also synchronized so that
both sampling rates are approximately the same (TC1 ∼ TC2 in
equation 1). Start both systems at the same time. Collect spectra
of at least 12 independent samples with each (spiked and unspiked)
system to obtain the minimum 24 measurements. Analyze the
analytical results using sections 12.1 and 12.2. Run averages can
be used in the statistical analysis instead of individual
measurements.
11.1.1.4 Compare to a Reference Method (RM). Obtain EPA approval
that the method qualifies as an RM for the analyte(s) and the
source to be tested. Follow the published procedures for the RM in
preparing and setting up equipment and sampling system, performing
measurements, and reporting results. Since FTIR CEMS have
multicomponent capability, it is possible to perform more than one
RM simultaneously, one for each target analyte. Conduct at least 9
runs where the FTIR CEM and the RM are sampling simultaneously.
Each Run is at least 30 minutes long and consists of spectra of at
least 5 independent FTIR CEM samples and the corresponding RM
measurements. If more than 9 runs are conducted, the analyst may
eliminate up to 3 runs from the analysis if at least 9 runs are
used.
11.1.1.4.1 RMs Using Integrated Sampling. Perform the RM and
FTIR CEM sampling simultaneously. The FTIR CEM can measure spectra
as frequently as the analyst chooses (and should obtain
measurements as frequently as possible) provided that the
measurements include spectra of at least 5 independent measurements
every 30 minutes. Concentration results from all of the FTIR CEM
spectra within a run may be averaged for use in the statistical
comparison even if all of the measurements are not independent.
When averaging the FTIR CEM concentrations within a run, it is
permitted to exclude some measurements from the average provided
the minimum of 5 independent measurements every 30 minutes are
included: The Run average of the FTIR CEM measurements depends on
both the sample flow rate and the measurement frequency (MF). The
run average of the RM using the integrated sampling method depends
primarily on its sampling rate. If the target analyte concentration
fluctuates significantly, the contribution to the run average of a
large fluctuation depends on the sampling rate and measurement
frequency, and on the duration and magnitude of the fluctuation. It
is, therefore, important to carefully select the sampling rate for
both the FTIR CEM and the RM and the measurement frequency for the
FTIR CEM. The minimum of 9 run averages can be compared according
to the relative accuracy test procedure in Performance
Specification 2 for SO2 and NOX CEMs (40 CFR, Part 60, App. B).
11.1.1.4.2 RMs Using a Grab Sampling Technique. Synchronize the
RM and FTIR CEM measurements as closely as possible. For a grab
sampling RM, record the volume collected and the exact sampling
period for each sample. Synchronize the FTIR CEM so that the FTIR
measures a spectrum of a similar cell volume at the same time as
the RM grab sample was collected. Measure at least five independent
samples with both the FTIR CEM and the RM for each of the minimum
nine runs. Compare the run concentration averages by using the
relative accuracy analysis procedure in Performance Specification 2
of appendix B of 40 CFR part 60.
11.1.1.4.3 Continuous Emission Monitors as RMs. If the RM is a
CEM, synchronize the sampling flow rates of the RM and the FTIR
CEM. Each run is at least 1 hour long and consists of at least 10
FTIR CEM measurements and the corresponding 10 RM measurements (or
averages). For the statistical comparison, use the relative
accuracy analysis procedure in Performance Specification 2 of
appendix B of 40 CFR part 60. If the RM time constant is < 1/2
the FTIR CEM time constant, brief fluctuations in analyte
concentrations that are not adequately measured with the slower
FTIR CEM time constant can be excluded from the run average along
with the corresponding RM measurements. However, the FTIR CEM run
average must still include at least 10 measurements over a 1-hour
period.
12.0 Calculations and Data Analysis
12.1 Spike Dilution Ratio, Expected Concentration. The Method
301 bias is calculated as follows.
Where: B = Bias at the spike level Sm = Mean of
the observed spiked sample concentrations Mm = Mean of the observed
unspiked sample concentrations CS = Expected value of the spiked
concentration.
The CS is determined by comparing the SF6 tracer concentration
in undiluted spike gas to the SF6 tracer concentrations in the
spiked samples;
The expected concentration (CS) is the measured
concentration of the analyte in undiluted spike gas divided by the
dilution factor Where: [anal]dir = The analyte
concentration in undiluted spike gas measured directly by filling
the FTIR cell with the spike gas. If the bias is statistically
significant (Section 12.2), Method 301 requires that a correction
factor, CF, be multiplied by the analytical results, and that 0.7
≤CF ≤1.3.
12.2 Statistical Analysis of Validation Measurements. Arrange
the independent measurements (or measurement averages) as in Table
1. More than 12 pairs of measurements can be analyzed. The
statistical analysis follows EPA Method 301, section 6.3. section
12.1 of this performance specification shows the calculations for
the bias, expected spike concentration, and correction factor. This
section shows the determination of the statistical significance of
the bias. Determine the statistical significance of the bias at the
95 percent confidence level by calculating the t-value for the set
of measurements. First, calculate the differences, di, for each
pair of spiked and each pair of unspiked measurements. Then
calculate the standard deviation of the spiked pairs of
measurements.
Where: di = The differences between pairs of
spiked measurements. SDs = The standard deviation in the di values.
n = The number of spiked pairs, 2n = 12 for the minimum of 12
spiked and 12 unspiked measurements. Calculate the relative
standard deviation, RSD, using SDs and the mean of the spiked
concentrations, Sm. The RSD must be ≤50%.
Repeat the calculations in equations 7 and 8 to determine SDu and
RSD, respectively, for the unspiked samples. Calculate the standard
deviation of the mean using SDs and SDu from equation 7.
The t-statistic is calculated as follows to
test the bias for statistical significance;
where the bias, B, and the correction factor, CF, are given in
section 12.1. For 11 degrees of freedom, and a one-tailed
distribution, Method 301 requires that t ≤2.201. If the t-statistic
indicates the bias is statistically significant, then analytical
measurements must be multiplied by the correction factor. There is
no limitation on the number of measurements, but there must be at
least 12 independent spiked and 12 independent unspiked
measurements. Refer to the t-distribution (Table 2) at the 95
percent confidence level and appropriate degrees of freedom for the
critical t-value. 13.0 Method Performance [Reserved] 14.0 Pollution
Prevention [Reserved] 15.0 Waste Management [Reserved] 16.0
References
1. Method 318, 40 CFR, Part 63, Appendix A (Draft), “Measurement
of Gaseous Formaldehyde, Phenol and Methanol Emissions by FTIR
Spectroscopy,” EPA Contract No. 68D20163, Work Assignment 2-18,
February, 1995.
2. “EPA Protocol for the Use of Extractive Fourier Transform
Infrared (FTIR) Spectrometry in Analyses of Gaseous Emissions from
Stationary Industrial Sources,” February, 1995.
3. “Measurement of Gaseous Organic and Inorganic Emissions by
Extractive FTIR Spectroscopy,” EPA Contract No. 68-D2-0165, Work
Assignment 3-08.
4. “Method 301 - Field Validation of Pollutant Measurement
Methods from Various Waste Media,” 40 CFR 63, App A.
17.0 Tables, Diagrams, Flowcharts, and Validation Data
Table 1 - Arrangement of Validation
Measurements for Statistical Analysis
Measurement
(or average)
Time
Spiked
(ppm)
di spiked
Unspiked
(ppm)
di unspiked
1
S1
U1
2
S2
S2−S1
U2
U2−U1
3
S3
U3
4
S4
S4−S3
U4
U4−U3
5
S5
U5
6
S6
S6−S5
U6
U6−U5
7
S7
U7
8
S8
S8−S7
U8
U8−U7
9
S9
U9
10
S10
S10−S9
U10
U10−U9
11
S11
U11
12
S12
S12−S11
U12
U12−U11
Average −>
Sm
Mm
Table 2 - t = Values
n−1 a
t−value
n−1 a
t−value
n−1 a
t−value
n−1 a
t−value
11
2.201
17
2.110
23
2.069
29
2.045
12
2.179
18
2.101
24
2.064
30
2.042
13
2.160
19
2.093
25
2.060
40
2.021
14
2.145
20
2.086
26
2.056
60
2.000
15
2.131
21
2.080
27
2.052
120
1.980
16
2.120
22
2.074
28
2.048
8
1.960
a n is the number of independent
pairs of measurements (a pair consists of one spiked and its
corresponding unspiked measurement). Either discreet (independent)
measurements in a single run, or run averages can be used.
Performance Specification 16 - Specifications and Test Procedures
for Predictive Emission Monitoring Systems in Stationary Sources
1.0 Scope and Application
1.1 Does this performance specification apply to me? If
you, the source owner or operator, intend to use (with any
necessary approvals) a predictive emission monitoring system (PEMS)
to show compliance with your emission limitation under 40 CFR 60,
61, or 63, you must use the procedures in this performance
specification (PS) to determine whether your PEMS is acceptable for
use in demonstrating compliance with applicable requirements. Use
these procedures to certify your PEMS after initial installation
and periodically thereafter to ensure the PEMS is operating
properly. If your PEMS contains a diluent (O2 or CO2) measuring
component and your emissions limitation is in units that require a
diluent measurement (e.g. lbs/mm Btu), the diluent component
must be tested as well. These specifications apply to PEMS that are
installed under 40 CFR 60, 61, and 63 after the effective date of
this performance specification. These specifications do not apply
to parametric monitoring systems, these are covered under
PS-17.
1.1.1 How do I certify my PEMS after it is installed?
PEMS must pass a relative accuracy (RA) test and accompanying
statistical tests in the initial certification test to be
acceptable for use in demonstrating compliance with applicable
requirements. Ongoing quality assurance tests also must be
conducted to ensure the PEMS is operating properly. An ongoing
sensor evaluation procedure must be in place before the PEMS
certification is complete. The amount of testing and data
validation that is required depends upon the regulatory needs,
i.e., whether precise quantification of emissions will be
needed or whether indication of exceedances of some regulatory
threshold will suffice. Performance criteria are more rigorous for
PEMS used in determining continual compliance with an emission
limit than those used to measure excess emissions. You must perform
the initial certification test on your PEMS before reporting any
PEMS data as quality-assured.
1.1.2 Is other testing required after certification?
After you initially certify your PEMS, you must pass additional
periodic performance checks to ensure the long-term quality of
data. These periodic checks are listed in the table in section 9.
You are always responsible for properly maintaining and operating
your PEMS.
2.0 Summary of Performance Specification
The following performance tests are required in addition to
other equipment and measurement location requirements.
2.1 Initial PEMS Certification.
2.1.1 Excess Emissions PEMS. For a PEMS that is used for excess
emission reporting, the owner or operator must perform a minimum
9-run, 3-level (3 runs at each level) RA test (see section
8.2).
2.1.2 Compliance PEMS. For a PEMS that is used for continual
compliance standards, the owner or operator must perform a minimum
27-run, 3-level (9 runs at each level) RA test (see section 8.2).
Additionally, the data must be evaluated for bias and by F-test and
correlation analysis.
2.2 Periodic Quality Assurance (QA) Assessments. Owners and
operators of all PEMS are required to conduct quarterly relative
accuracy audits (RAA) and yearly relative accuracy test audits
(RATA) to assess ongoing PEMS operation. The frequency of these
periodic assessments may be shortened by successful operation
during a prior year.
3.0 Definitions
The following definitions apply:
3.1 Centroidal Area means that area in the center of the
stack (or duct) comprising no more than 1 percent of the stack
cross-sectional area and having the same geometric shape as the
stack.
3.2 Data Recorder means the equipment that provides a
permanent record of the PEMS output. The data recorder may include
automatic data reduction capabilities and may include electronic
data records, paper records, or a combination of electronic data
and paper records.
3.3 Defective sensor means a sensor that is responsible
for PEMS malfunction or that operates outside the approved
operating envelope. A defective sensor may be functioning properly,
but because it is operating outside the approved operating
envelope, the resulting predicted emission is not validated.
3.4 Diluent PEMS means the total equipment required to
predict a diluent gas concentration or emission rate.
3.5 Operating envelope means the defined range of a
parameter input that is established during PEMS development.
Emission data generated from parameter inputs that are beyond the
operating envelope are not considered quality assured and are
therefore unacceptable.
3.6 PEMS means all of the equipment required to predict
an emission concentration or emission rate. The system may consist
of any of the following major subsystems: sensors and sensor
interfaces, emission model, algorithm, or equation that uses
process data to generate an output that is proportional to the
emission concentration or emission rate, diluent emission model,
data recorder, and sensor evaluation system. Systems that use fewer
than 3 variables do not qualify as PEMS unless the system has been
specifically approved by the Administrator for use as a PEMS. A
PEMS may predict emissions data that are corrected for diluent if
the relative accuracy and relevant QA tests are passed in the
emission units corrected for diluent. Parametric monitoring systems
that serve as indicators of compliance and have parametric
limits but do not predict emissions to comply with an
emissions limit are not included in this definition.
3.7 PEMS training means the process of developing or
confirming the operation of the PEMS against a reference method
under specified conditions.
3.8 Quarter means a quarter of a calendar year in which
there are at least 168 unit operating hours.
3.9 Reconciled Process Data means substitute data that
are generated by a sensor evaluation system to replace that of a
failed sensor. Reconciled process data may not be used without
approval from the Administrator.
3.10 Relative Accuracy means the accuracy of the PEMS
when compared to a reference method (RM) at the source. The RA is
the average difference between the pollutant PEMS and RM data for a
specified number of comparison runs plus a 2.5 percent confidence
coefficient, divided by the average of the RM tests. For a diluent
PEMS, the RA may be expressed as a percentage of absolute
difference between the PEMS and RM. Alternative specifications are
given for units that have very low emissions.
3.11 Relative Accuracy Audit means a quarterly audit of
the PEMS against a portable analyzer meeting the requirements of
ASTM D6522-00 or a RM for a specified number of runs. A RM may be
used in place of the portable analyzer for the RAA.
3.12 Relative Accuracy Test Audit means a RA test that is
performed at least once every four calendar quarters after the
initial certification test while the PEMS is operating at the
normal operating level.
3.13 Reference Value means a PEMS baseline value that may
be established by RM testing under conditions when all sensors are
functioning properly. This reference value may then be used in the
sensor evaluation system or in adjusting new sensors.
3.14 Sensor Evaluation System means the equipment or
procedure used to periodically assess the quality of sensor input
data. This system may be a sub-model that periodically cross-checks
sensor inputs among themselves or any other procedure that checks
sensor integrity at least daily (when operated for more than one
hour in any calendar day).
3.15 Sensors and Sensor Interface means the equipment
that measures the process input signals and transports them to the
emission prediction system.
4.0 Interferences [Reserved] 5.0 Safety [Reserved] 6.0 Equipment
and Supplies
6.1 PEMS Design. You must detail the design of your PEMS and
make this available in reports and for on-site inspection. You must
also establish the following, as applicable:
6.1.1 Number of Input Parameters. An acceptable PEMS will
normally use three or more input parameters. You must obtain the
Administrator's permission on a case-by-case basis if you desire to
use a PEMS having fewer than three input parameters.
6.1.2 Parameter Operating Envelopes. Before you evaluate your
PEMS through the certification test, you must specify the input
parameters your PEMS uses, define their range of minimum and
maximum values (operating envelope), and demonstrate the integrity
of the parameter operating envelope using graphs and data from the
PEMS development process, vendor information, or engineering
calculations, as appropriate. If you operate the PEMS beyond these
envelopes at any time after the certification test, the data
generated during this condition will not be acceptable for use in
demonstrating compliance with applicable requirements. If these
parameter operating envelopes are not clearly defined and supported
by development data, the PEMS operation will be limited to the
range of parameter inputs encountered during the certification test
until the PEMS has a new operating envelope established.
6.1.3 Source-Specific Operating Conditions. Identify any
source-specific operating conditions, such as fuel type, that
affect the output of your PEMS. You may only use the PEMS under the
source-specific operating conditions it was certified for.
6.1.4 Ambient Conditions. You must explain whether and how
ambient conditions and seasonal changes affect your PEMS. Some
parameters such as absolute ambient humidity cannot be manipulated
during a test. The effect of ambient conditions such as humidity on
the pollutant concentration must be determined and this effect
extrapolated to include future anticipated conditions. Seasonal
changes and their effects on the PEMS must be evaluated unless you
can show that such effects are negligible.
6.1.5 PEMS Principle of Operation. If your PEMS is developed on
the basis of known physical principles, you must identify the
specific physical assumptions or mathematical manipulations that
support its operation. If your PEMS is developed on the basis of
linear or nonlinear regression analysis, you must make available
the paired data (preferably in graphic form) used to develop or
train the model.
6.1.6 Data Recorder Scale. If you are not using a digital
recorder, you must choose a recorder scale that accurately captures
the desired range of potential emissions. The lower limit of your
data recorder's range must be no greater than 20 percent of the
applicable emission standard (if subject to an emission standard).
The upper limit of your data recorder's range must be determined
using the following table. If you obtain approval first, you may
use other lower and upper recorder limits.
If PEMS is measuring. .
.
And if. . .
Then your upper limit. .
.
Uncontrolled
emissions, such as NOX at the stack of a natural gas-fired
boiler
No other regulation sets an
upper limit for the data recorder's range
Must be 1.25 to 2 times the
average potential emission level
Uncontrolled
emissions, such as NOX at the stack of a natural gas-fired
boiler
Another regulation sets an
upper limit for the data recorder's range
Must follow the other
regulation
Controlled
emissions
Must be 1.5 to 2.0 times
concentration of the emission standard that applies to your
emission unit
Continual
compliance emissions for an applicable regulation
Must be 1.1 to 1.5 times the
concentration of the emission standard that applies to your
emission unit
6.1.7 Sensor Location and Repair. We recommend you install
sensors in an accessible location in order to perform repairs and
replacements. Permanently-installed platforms or ladders may not be
needed. If you install sensors in an area that is not accessible,
you may be required to shut down the emissions unit to repair or
replace a sensor. Conduct a new RATA after replacing a sensor that
supplies a critical PEMS parameter if the new sensor provides a
different output or scaling or changes the historical training
dataset of the PEMS. Replacement of a non-critical sensor that does
not cause an impact in the accuracy of the PEMS does not trigger a
RATA. All sensors must be calibrated as often as needed but at
least as often as recommended by the manufacturers.
6.1.8 Sensor Evaluation System. Your PEMS must be designed to
perform automatic or manual determination of defective sensors on
at least a daily basis. This sensor evaluation system may consist
of a sensor validation sub-model, a comparison of redundant
sensors, a spot check of sensor input readings at a reference
value, operation, or emission level, or other procedure that
detects faulty or failed sensors. Some sensor evaluation systems
generate substitute values (reconciled data) that are used when a
sensor is perceived to have failed. You must obtain prior approval
before using reconciled data.
6.1.9 Parameter Envelope Exceedances. Your PEMS must include a
plan to detect and notify the operator of parameter envelope
exceedances. Emission data collected outside the ranges of the
sensor envelopes will not be considered quality assured.
6.2 Recordkeeping. All valid data recorded by the PEMS must be
used to calculate the emission value.
7.0 Reagents and Standards [Reserved] 8.0 Sample Collection,
Preservation, Storage, and Transport
8.1 Initial Certification. Use the following procedure to
certify your PEMS. Complete all PEMS training before the
certification begins.
8.2 Relative Accuracy Test.
8.2.1 Reference Methods. Unless otherwise specified in the
applicable regulations, you must use the test methods in appendix A
of this part for the RM test. Conduct the RM tests at three
operating levels. The RM tests shall be performed at a low-load (or
production) level between the minimum safe, stable load and 50
percent of the maximum level load, at the mid-load level (an
intermediary level between the low and high levels), and at a
high-load level between 80 percent and the maximum load.
Alternatively, if practicable, you may test at three levels of the
key operating parameter (e.g. selected based on a covariance
analysis between each parameter and the PEMS output) equally spaced
within the normal range of the parameter.
8.2.2 Number of RM Tests for Excess Emission PEMS. For PEMS used
for excess emission reporting, conduct at least the following
number of RM tests at the following key parameter operating
levels:
(1) Three at a low level.
(2) Three at a mid level.
(3) Three at a high level.
You may choose to perform more than nine total RM tests. If you
perform more than nine tests, you may reject a maximum of three
tests as long as the total number of test results used to determine
the RA is nine or greater and each operating level has at least
three tests. You must report all data, including the rejected
data.
8.2.3 Number of RM Tests for Continual Compliance PEMS. For PEMS
used to determine compliance, conduct at least the following number
of RM tests at the following key parameter operating levels:
(1) Nine at a low level.
(2) Nine at a mid level.
(3) Nine at a high level.
You may choose to perform more than 9 RM runs at each operating
level. If you perform more than 9 runs, you may reject a maximum of
three runs per level as long as the total number of runs used to
determine the RA at each operating level is 9 or greater.
8.2.4 Reference Method Measurement Location. Select an
accessible measurement point for the RM that will ensure you
measure emissions representatively. Ensure the location is at least
two equivalent stack diameters downstream and half an equivalent
diameter upstream from the nearest flow disturbance such as the
control device, point of pollutant generation, or other place where
the pollutant concentration or emission rate can change. You may
use a half diameter downstream instead of the two diameters if you
meet both of the following conditions:
(1) Changes in the pollutant concentration are caused solely by
diluent leakage, such as leaks from air heaters.
(2) You measure pollutants and diluents simultaneously at the
same locations.
8.2.5 Traverse Points. Select traverse points that ensure
representative samples. Conduct all RM tests within 3 cm of each
selected traverse point but no closer than 3 cm to the stack or
duct wall. The minimum requirement for traverse points are as
follows:
(1) Establish a measurement line across the stack that passes
through the center and in the direction of any expected
stratification.
(2) Locate a minimum of three traverse points on the line at
16.7, 50.0, and 83.3 percent of the stack inside diameter.
(3) Alternatively, if the stack inside diameter is greater than
2.4 meters, you may locate the three traverse points on the line at
0.4, 1.2, and 2.0 meters from the stack or duct wall. You may not
use this alternative option after wet scrubbers or at points where
two streams with different pollutant concentrations are combined.
You may select different traverse points if you demonstrate and
provide verification that it provides a representative sample. You
may also use the traverse point specifications given the RM.
8.2.6 Relative Accuracy Procedure. Perform the number of RA
tests at the levels required in sections 8.2.2 and 8.2.3. For
integrated samples (e.g., Method 3A or 7E), make a sample
traverse of at least 21 minutes, sampling for 7 minutes at each
traverse point. For grab samples (e.g., Method 3 or 7), take
one sample at each traverse point, scheduling the grab samples so
that they are taken simultaneously (within a 3-minute period) or at
an equal interval of time apart over a 21-minute period. A test run
for grab samples must be made up of at least three separate
measurements. Where multiple fuels are used in the monitored unit
and the fuel type affects the predicted emissions, determine a RA
for each fuel unless the effects of the alternative fuel on
predicted emissions or diluent were addressed in the model training
process. The unit may only use fuels that have been evaluated this
way.
8.2.7 Correlation of RM and PEMS Data. Mark the beginning and
end of each RM test run (including the exact time of day) on the
permanent record of PEMS output. Correlate the PEMS and the RM test
data by the time and duration using the following steps:
A. Determine the integrated pollutant concentration for the PEMS
for each corresponding RM test period.
B. Consider system response time, if important, and confirm that
the pair of results is on a consistent moisture, temperature, and
diluent concentration basis.
C. Compare each average PEMS value to the corresponding average
RM value. Use the following guidelines to make these
comparisons.
If . . .
Then . . .
And then . . .
The RM has an
instrumental or integrated non-instrumental sampling technique
Directly compare RM and PEMS
results
The RM has a grab
sampling technique
Average the results from all
grab samples taken during the test run. The test run must include
≥3 separate grab measurements
Compare this average RM result
with the PEMS result obtained during the run.
Use the paired PEMS and RM data and the equations in section
12.2 to calculate the RA in the units of the applicable emission
standard. For this 3-level RA test, calculate the RA at each
operation level.
8.3 Statistical Tests for PEMS that are Used for Continual
Compliance. In addition to the RA determination, evaluate the
paired RA and PEMS data using the following statistical tests.
8.3.1 Bias Test. From the RA data taken at the mid-level,
determine if a bias exists between the RM and PEMS. Use the
equations in section 12.3.1.
8.3.2 F-test. Perform a separate F-test for the RA paired data
from each operating level to determine if the RM and PEMS variances
differ by more than might be expected from chance. Use the
equations in section 12.3.2.
8.3.3 Correlation Analysis. Perform a correlation analysis using
the RA paired data from all operating levels combined to determine
how well the RM and PEMS correlate. Use the equations in section
12.3.3. The correlation is waived if the process cannot be varied
to produce a concentration change sufficient for a successful
correlation test because of its technical design. In such cases,
should a subsequent RATA identify a variation in the RM measured
values by more than 30 percent, the waiver will not apply, and a
correlation analysis test must be performed at the next RATA.
8.4 Reporting. Summarize in tabular form the results of the RA
and statistical tests. Include all data sheets, calculations, and
charts (records of PEMS responses) necessary to verify that your
PEMS meets the performance specifications. Include in the report
the documentation used to establish your PEMS parameter
envelopes.
8.5 Reevaluating Your PEMS After a Failed Test, Change in
Operations, or Change in Critical PEMS Parameter. After initial
certification, if your PEMS fails to pass a quarterly RAA or yearly
RATA, or if changes occur or are made that could result in a
significant change in the emission rate (e.g., turbine
aging, process modification, new process operating modes, or
changes to emission controls), your PEMS must be recertified using
the tests and procedures in section 8.1. For example, if you
initially developed your PEMS for the emissions unit operating at
80-100 percent of its range, you would have performed the initial
test under these conditions. Later, if you wanted to operate the
emission unit at 50-100 percent of its range, you must conduct
another RA test and statistical tests, as applicable, to verify
that the new conditions of 50-100 percent of range are functional.
These tests must demonstrate that your PEMS provides acceptable
data when operating in the new range or with the new critical PEMS
parameter(s). The requirements of section 8.1 must be completed by
the earlier of 60 unit operating days or 180 calendar days after
the failed RATA or after the change that caused a significant
change in emission rate.
9.0 Quality Control
You must incorporate a QA plan beyond the initial PEMS
certification test to verify that your system is generating
quality-assured data. The QA plan must include the components of
this section.
9.1 QA/QC Summary. Conduct the applicable ongoing tests listed
below.
Ongoing Quality Assurance Tests
Test
PEMS regulatory
purpose
Acceptability
Frequency
Sensor
Evaluation
All
Daily.
RAA
Compliance
3-test avg ≤10% of
simultaneous analyzer or RM average
Each quarter except quarter
when RATA performed.
RATA
All
Same as for RA in Sec.
13.1
Yearly in quarter when RAA not
performed.
Bias
Correction
All
If davg ≤ |cc|
Bias test passed (no
correction factor needed).
PEMS Training
All
If Fcritical ≥F
r ≥0.8
Optional after initial and
subsequent RATAs.
Sensor Evaluation
Alert Test (optional)
All
See Section 6.1.8
After each PEMS training.
9.2 Daily Sensor Evaluation Check. Your sensor evaluation system
must check the integrity of each PEMS input at least daily.
9.3 Quarterly Relative Accuracy Audits. In the first year of
operation after the initial certification, perform a RAA consisting
of at least three 30-minute portable analyzer or RM determinations
each quarter a RATA is not performed. To conduct a RAA, follow the
procedures in Section 8.2 for the relative accuracy test, except
that only three sets of measurement data are required, and the
statistical tests are not required. The average of the three or
more portable analyzer or RM determinations must not exceed the
limits given in Section 13.5. Report the data from all sets of
measurement data. If a PEMS passes all quarterly RAAs in the first
year and also passes the subsequent yearly RATA in the second year,
you may elect to perform a single mid-year RAA in the second year
in place of the quarterly RAAs. This option may be repeated, but
only until the PEMS fails either a mid-year RAA or a yearly RATA.
When such a failure occurs, you must resume quarterly RAAs in the
quarter following the failure and continue conducting quarterly
RAAs until the PEMS successfully passes both a year of quarterly
RAAs and a subsequent RATA.
9.4 Yearly Relative Accuracy Test. Perform a minimum 9-run RATA
at the normal operating level on a yearly basis in the quarter that
the RAA is not performed. The statistical tests in Section 8.3 are
not required for the yearly RATA.
10.0 Calibration and Standardization [Reserved] 11.0 Analytical
Procedure [Reserved] 12.0 Calculations and Data Analysis 12.1
Nomenclature B = PEMS bias adjustment factor. cc = Confidence
coefficient. di = Difference between each RM and PEMS run. d =
Arithmetic mean of differences for all runs. ei = Individual
measurement provided by the PEMS or RM at a particular level. em =
Mean of the PEMS or RM measurements at a particular level. ep =
Individual measurement provided by the PEMS. ev = Individual
measurement provided by the RM. F = Calculated F-value. n = Number
of RM runs. PEMSi = Individual measurement provided by the PEMS.
PEMSiAdjusted = Individual measurement provided by the PEMS
adjusted for bias. PEMS = Mean of the values provided by the PEMS
at the normal operating range during the bias test. r = Coefficient
of correlation. RA = Relative accuracy. RAA = Relative accuracy
audit. RM = Average RM value (or in the case of the RAA, the
average portable analyzer value). In cases where the average
emissions for the test are less than 50 percent of the applicable
standard, substitute the emission standard value here in place of
the average RM value. Sd = Standard deviation of differences. S 2 =
Variance of your PEMS or RM. t0.025 = t-value for a one-sided, 97.5
percent confidence interval (see Table 16-1).
12.2 Relative Accuracy Calculations. Calculate the mean of the
RM values. Calculate the differences between the pairs of
observations for the RM and the PEMS output sets. Finally,
calculate the mean of the differences, standard deviation,
confidence coefficient, and PEMS RA, using Equations 16-1, 16-2,
16-3, and 16-4, respectively. For compliance PEMS, calculate the RA
at each test level. The PEMS must pass the RA criterion at each
test level.
12.2.1 Arithmetic Mean. Calculate the arithmetic mean of the
differences between paired RM and PEMS observations using Equation
16-1.
12.2.2 Standard Deviation. Calculate the standard deviation of
the differences using Equation 16-2 (positive square root).
12.2.3 Confidence Coefficient. Calculate the confidence
coefficient using Equation 16-3 and Table 16-1 for n−1 degrees of
freedom.
12.2.4 Relative Accuracy. Calculate the RA of your data using
Equation 16-4.
12.3 Compliance PEMS Statistical Tests. If your PEMS will be
used for continual compliance purposes, conduct the following tests
using the information obtained during the RA tests. For the
pollutant measurements at any one test level, if the mean value of
the RM is less than either 10 ppm or 5 percent of the emission
standard, all statistical tests are waived at that specific test
level. For diluent measurements at any one test level, if the mean
value of the RM is less than 3 percent of span, all statistical
tests are waived for that specific test level.
12.3.1 Bias Test. Conduct a bias test to determine if your PEMS
is biased relative to the RM. Determine the PEMS bias by comparing
the confidence coefficient obtained from Equation 16-3 to the
arithmetic mean of the differences determined in Equation 16-1. If
the arithmetic mean of the differences (d ) is greater than the
absolute value of the confidence coefficient (cc), your PEMS must
incorporate a bias factor to adjust future PEMS values as in
Equation 16-5.
Where:
12.3.2 F-test. Conduct an F-test for each of the three RA data
sets collected at different test levels. Calculate the variances of
the PEMS and the RM using Equation 16-6.
Determine if the variance of the PEMS data is
significantly different from that of the RM data at each level by
calculating the F-value using Equation 16-7.
Compare the calculated F-value with the critical value of F at the
95 percent confidence level with n-1 degrees of freedom. The
critical value is obtained from Table 16-2 or a similar table for
F-distribution. If the calculated F-value is greater than the
critical value at any level, your proposed PEMS is unacceptable.
For pollutant PEMS measurements, if the standard deviation of the
RM is less than either 3 percent of the span or 5 ppm, use a RM
standard deviation of either 5 ppm or 3 percent of span. For
diluent PEMS measurements, if the standard deviation of the
reference method is less than 3 percent of span, use a RM standard
deviation of 3 percent of span.
12.3.3 Correlation Analysis. Calculate the correlation
coefficient either manually using Eq. 16-8, on a graph, or by
computer using all of the paired data points from all operating
levels. Your PEMS correlation must be 0.8 or greater to be
acceptable. If during the initial certification test, your PEMS
data are determined to be auto-correlated according to the
procedures in 40 CFR 75.41(b)(2), or if the signal-to-noise ratio
of the data is less than 4, then the correlation analysis is
permanently waived.
12.4 Relative Accuracy Audit. Calculate the quarterly RAA using
Equation 16-9.
13.0
Method Performance
13.1 PEMS Relative Accuracy. The RA must not exceed 10 percent
if the PEMS measurements are greater than 100 ppm or 0.2 lbs/mm
Btu. The RA must not exceed 20 percent if the PEMS measurements are
between 100 ppm (or 0.2 lb/mm Btu) and 10 ppm (or 0.05 lb/mm Btu).
For measurements below 10 ppm, the absolute mean difference between
the PEMS measurements and the RM measurements must not exceed 2
pppm. For diluent PEMS, an alternative criterion of ±1 percent
absolute difference between the PEMS and RM may be used if less
stringent.
13.2 PEMS Bias. Your PEMS data is considered biased and must be
adjusted if the arithmetic mean (d) is greater than the absolute
value of the confidence coefficient (cc) in Equations 16.1 and
16.3. In such cases, a bias factor must be used to correct your
PEMS data.
13.3 PEMS Variance. Your calculated F-value must not be greater
than the critical F-value at the 95-percent confidence level for
your PEMS to be acceptable.
13.4 PEMS Correlation. Your calculated r-value must be greater
than or equal to 0.8 for your PEMS to be acceptable.
13.5 Relative Accuracy Audits. The average of the three portable
analyzer or RM determinations must not differ from the simultaneous
PEMS average value by more than 10 percent of the analyzer or RM
for concentrations greater than 100 ppm or 20 percent for
concentrations between 100 and 20 ppm, or the test is failed. For
measurements at 20 ppm or less, this difference must not exceed 2
ppm for a pollutant PEMS and 1 percent absolute for a diluents
PEMS.
14.0 Pollution Prevention [Reserved] 15.0 Waste Management
[Reserved] 16.0 References [Reserved] 17.0 Tables, Diagrams,
Flowcharts, and Validation Data
Table 16-1 - t-Values for One-sided, 97.5
Percent Confidence Intervals for Selected Sample Sizes *
n−1 *
t-value
n−1
t-value
1
12.706
15
2.131
2
4.303
16
2.120
3
3.182
17
2.110
4
2.776
18
2.101
5
2.571
19
2.093
6
2.447
20
2.086
7
2.365
21
2.080
8
2.306
22
2.074
9
2.262
23
2.069
10
2.228
24
2.064
11
2.201
25
2.060
12
2.179
26
2.056
13
2.160
27
2.052
14
2.145
>28
t-Table
* The value n is the number of RM runs; n−1
equals the degrees of freedom.
Performance Specification 17 [Reserved] Performance Specification
18 - Performance Specifications and Test Procedures for Gaseous
Hydrogen Chloride (HCI) Continuous Emission Monitoring Systems at
Stationary Sources 1.0 Scope and Application
1.1 Analyte. This performance specification (PS) is applicable
for measuring gaseous concentrations of hydrogen chloride (HCl),
CAS: 7647-01-0, on a continuous basis in the units of the
applicable standard or in units that can be converted to units of
the applicable standard(s).
1.2 Applicability.
1.2.1 This specification is used to evaluate the acceptability
of HCl continuous emission monitoring systems (CEMS) at the time of
installation or soon after and whenever specified in the
regulations. The specification includes requirements for initial
acceptance including instrument accuracy and stability assessments
and use of audit samples if they are available.
1.2.2 The Administrator may require the operator, under section
114 of the Clean Air Act, to conduct CEMS performance evaluations
at other times besides the initial test to evaluate the CEMS
performance. See 40 CFR part 60, §§ 60.13(c) and 63.8(e)(1).
1.2.3 A source that demonstrates their CEMS meets the criteria
of this PS may use the system to continuously monitor gaseous HCl
under any regulation or permit that requires compliance with this
PS. If your CEMS is capable of reporting the HCl concentration in
the units of the applicable standard, no additional CEMS components
are necessary. If your CEMS does not report concentrations in the
units of the existing standard, then other CEMS components
(e.g., oxygen (O2), temperature, stack gas flow, moisture
and pressure) may be necessary to convert the units reported by
your CEMS to the units of the standard.
1.2.4 These specification test results are intended to be valid
for the life of the system. As a result, the HCl measurement system
must be tested and operated in a configuration consistent with the
configuration that will be used for ongoing continuous emissions
monitoring.
1.2.5 Substantive changes to the system configuration require
retesting according to this PS. Examples of such conditions
include, but are not limited to: major changes in dilution ratio
(for dilution based systems); changes in sample conditioning and
transport, if used, such as filtering device design or materials;
changes in probe design or configuration and changes in materials
of construction. Changes consistent with instrument manufacturer
upgrade that fall under manufacturer's certification do not require
additional field verification. Manufacturer's upgrades require
recertification by the manufacturer for those requirements allowed
by this PS, including interference, level of detection (LOD), and
light intensity qualification.
1.2.6 This specification is not designed to evaluate the ongoing
CEMS performance nor does it identify specific calibration
techniques and auxiliary procedures to assess CEMS performance over
an extended period of time. The requirements in appendix F,
Procedure 6 are designed to provide a way to assess CEMS
performance over an extended period of time. The source owner or
operator is responsible to calibrate, maintain, and operate the
CEMS properly.
2.0 Summary of Performance Specification
2.1 This specification covers the procedures that each CEMS must
meet during the performance evaluation test. Installation and
measurement location specifications, data reduction procedures, and
performance criteria are included.
2.2 The technology used to measure gaseous HCl must provide a
distinct response and address any appropriate interference
correction(s). It must accurately measure gaseous HCl in a
representative sample (path or point sampling) of stack
effluent.
2.3 The relative accuracy (RA) must be established against a
reference method (RM) (e.g., Method 26A, Method 320, ASTM
International (ASTM) D6348-12, including mandatory annexes, or
Method 321 for Portland cement plants as specified by the
applicable regulation or, if not specified, as appropriate for the
source concentration and category). Method 26 may be approved as a
RM by the Administrator on a case-by-case basis if not otherwise
allowed or denied in an applicable regulation.
2.4 A standard addition (SA) procedure using a reference
standard is included in appendix A to this performance
specification for use in verifying LOD. For extractive CEMS, where
the SA is done by dynamic spiking (DS), the appendix A procedure is
allowed as an option for assessing calibration drift and is also
referenced by Procedure 6 of appendix F to this part for ongoing
quality control tests.
3.0 Definitions
3.1 Beam attenuation is the reduction in electromagnetic
radiation (light) throughput from the maximum beam intensity
experienced during site specific CEMS operation.
3.2 Beam intensity is the electromagnetic radiation
(light) throughput for an IP-CEMS instrument measured following
manufacturers specifications.
3.3 Calibration cell means a gas containment cell used
with cross stack or integrated path (IP) CEMS for calibration and
to perform many of the test procedures required by this performance
specification. The cell may be a removable sealed cell or an
evacuated and/or purged cell capable of exchanging reference and
other calibration gases as well as zero gas standards. When
charged, it contains a known concentration of HCl and/or
interference gases. The calibration cell is filled with zero gas or
removed from the optical path during stack gas measurement.
3.4 Calibration drift (CD) means the absolute value of
the difference between the CEMS output response and an upscale
reference gas or a zero-level gas, expressed as a percentage of the
span value, when the CEMS is challenged after a stated period of
operation during which no unscheduled adjustments, maintenance or
repairs took place.
3.5 Centroidal area means a central area that is
geometrically similar to the stack or duct cross section and is no
greater than 10 percent of the stack or duct cross-sectional
area.
3.6 Continuous Emission Monitoring System (CEMS) means
the total equipment required to measure the pollutant concentration
or emission rate continuously. The system generally consists of the
following three major subsystems:
3.6.1 Sample interface means that portion of the CEMS
used for one or more of the following: Sample acquisition, sample
transport, sample conditioning, defining the optical measurement
path, and protection of the monitor from the effects of the stack
effluent.
3.6.2 HCl analyzer means that portion of the HCl CEMS
that measures the total vapor phase HCl concentration and generates
a proportional output.
3.6.3 Data recorder means that portion of the CEMS that
provides a permanent electronic record of the analyzer output. The
data recorder may record other pertinent data such as effluent flow
rates, various instrument temperatures or abnormal CEMS operation.
The data recorder may also include automatic data reduction
capabilities and CEMS control capabilities.
3.7 Diluent gas means a major gaseous constituent in a
gaseous pollutant mixture. For combustion sources, either carbon
dioxide (CO2) or oxygen (O2) or a combination of these two gases
are the major gaseous diluents of interest.
3.8 Dynamic spiking (DS) means the procedure where a
known concentration of HCl gas is injected into the probe sample
gas stream for extractive CEMS at a known flow rate to assess the
performance of the measurement system in the presence of potential
interference from the flue gas sample matrix.
3.9 Independent measurement(s) means the series of CEMS
data values taken during sample gas analysis separated by two times
the procedure specific response time (RT) of the CEMS.
3.10 Integrated path CEMS (IP-CEMS) means an in-situ CEMS
that measures the gas concentration along an optical path in the
stack or duct cross section.
3.11 Interference means a compound or material in the
sample matrix other than HCl whose characteristics may bias the
CEMS measurement (positively or negatively). The interference may
not prevent the sample measurement, but could increase the
analytical uncertainty in the measured HCl concentration through
reaction with HCl or by changing the electronic signal generated
during HCl measurement.
3.12 Interference test means the test to detect CEMS
responses to interferences that are not adequately accounted for in
the calibration procedure and may cause measurement bias.
3.13 Level of detection (LOD) means the lowest level of
pollutant that the CEMS can detect in the presence of the source
gas matrix interferents with 99 percent confidence.
3.14 Liquid evaporative standard means a reference gas
produced by vaporizing National Institute of Standards and
Technology (NIST) traceable liquid standards of known HCl
concentration and quantitatively diluting the resultant vapor with
a carrier gas.
3.15 Measurement error (ME) is the mean difference
between the concentration measured by the CEMS and the known
concentration of a reference gas standard, divided by the span,
when the entire CEMS, including the sampling interface, is
challenged.
3.16 Optical path means the route light travels from the
light source to the receiver used to make sample measurements.
3.17 Path length means, for an extractive optical CEMS,
the distance in meters of the optical path within a gas measurement
cell. For an IP-CEMS, path length means the distance in meters of
the optical path that passes through the source gas in the stack or
duct.
3.18 Point CEMS means a CEMS that measures the source gas
concentration, either at a single point at the sampling probe tip
or over a path length for IP-CEMS less than 10 percent of the
equivalent diameter of the stack or duct cross section.
3.19 Stack pressure measurement device means a
NIST-traceable gauge or monitor that measures absolute pressure and
conforms to the design requirements of ASME B40.100-2010, “Pressure
Gauges and Gauge Attachments” (incorporated by reference - see §
60.17).
3.20 Reference gas standard means a NIST-traceable gas
standard containing a known concentration of HCl certified in
accordance with an EPA traceability protocol in section 7.1 of this
PS.
3.21 Relative accuracy (RA) means the absolute mean
difference between the gas concentration or the emission rate
determined by the CEMS and the value determined by the RM, plus the
confidence coefficient of a series of nine test runs, divided by
the average of the RM or the applicable emission standard.
3.22 Response time (RT) means the time it takes for the
measurement system, while operating normally at its target sample
flow rate, dilution ratio, or data collection rate to respond to a
known step change in gas concentration, either from a low- or
zero-level to a high-level gas concentration or from a high-level
to a low or zero-level gas concentration, and to read 95 percent of
the change to the stable instrument response. There may be several
RTs for an instrument related to different functions or procedures
(e.g., DS, LOD, and ME).
3.23 Span value means an HCl concentration approximately
equal to two times the concentration equivalent to the emission
standard unless otherwise specified in the applicable regulation,
permit or other requirement. Unless otherwise specified, the span
may be rounded up to the nearest multiple of 5.
3.24 Standard addition means the addition of known
amounts of HCl gas (either statically or dynamically) to the actual
measurement path or measured sample gas stream.
3.25 Zero gas means a gas or liquid with an HCl
concentration that is below the LOD of the measurement system.
4.0 Interferences
Sample gas interferences will vary depending on the instrument
or technology used to make the measurement. Interferences must be
evaluated through the interference test in this PS. Several
compounds including carbon dioxide (CO2), carbon monoxide (CO),
formaldehyde (CH2O), methane (CH4), and water (H2O) are potential
optical interferences with certain types of HCl monitoring
technology. Ammonia is a potential chemical interference with
HCl.
5.0 Safety
The procedures required under this PS may involve hazardous
materials, operations, and equipment. This PS may not address all
of the safety issues associated with these procedures. It is the
responsibility of the user to establish appropriate safety and
health practices and determine the applicable regulatory
limitations prior to performing these procedures. The CEMS user's
manual and materials recommended by the RM should be consulted for
specific precautions to be taken.
6.0 Equipment and Supplies
Equipment and supplies for CEMS will vary depending on the
measurement technology and equipment vendors. This section provides
a description of the equipment and supplies typically found in one
or more types of CEMS.
6.1 Sample Extraction System. The portion of an extractive CEMS
that collects and transports the sample to the pressure regulation
and sample conditioning module. The extraction system must deliver
a representative sample to the measurement instrument. The sample
extraction system typically consists of a sample probe and a heated
umbilical line.
6.2 Sample Conditioning Module. The portion of an extractive
CEMS that removes particulate matter and moisture from the gas
stream and provides a sample gas stream to the CEMS analysis module
or analyzer. You must keep the particle-free gas sample above the
dew point temperature of its components.
6.3 HClAnalyzer. The portion of the CEMS that detects,
quantifies and generates an output proportional to the sample gas
HCl concentration.
6.4 System Controller. The portion of the CEMS that provides
control of the analyzer and other sub-systems (e.g., sample
extraction, sample conditioning, reference gas) as necessary for
continuous operation and periodic maintenance/QC activities.
6.5 Data Recorder. The portion of the CEMS that provides a
record of analyzer output. The data recorder may record other
pertinent data such as effluent flow rates, various instrument
temperatures or abnormal CEMS operation. The data recorder output
range must include the full range of expected HCl concentration
values in the gas stream to be sampled including zero and span
value.
6.6 Reference Gas System(s). Gas handling system(s) needed to
introduce reference and other gases into the measurement system.
For extractive CEMS, the system must be able to introduce gas flow
sufficient to flood the sampling probe and prevent entry of gas
from the effluent stream. For IP-CEMS, the system must be able to
introduce a known concentration of HCl, at known cell length,
pressure and temperature, into the optical path used to measure HCl
gas concentration.
6.7 Moisture Measurement System. If correction of the measured
HCl emissions for moisture is required, you must install, operate,
maintain, and quality assure a continuous moisture monitoring
system for measuring and recording the moisture content of the flue
gases. The following continuous moisture monitoring systems are
acceptable: An FTIR system validated according to Method 301 or
section 13.0 of Method 320 in appendix A to part 63 of this
chapter; a continuous moisture sensor; an oxygen analyzer (or
analyzers) capable of measuring O2 both on a wet basis and on a dry
basis; a stack temperature sensor and a moisture look-up table,
i.e., a psychrometric chart (for saturated gas streams
following wet scrubbers or other demonstrably saturated gas
streams, only); or other continuous moisture measurement methods
approved by the Administrator. Alternatively, for any type of fuel,
you may determine an appropriate site-specific default moisture
value (or values), using measurements made with Method 4 -
Determination of Moisture Content In Stack Gases, in appendix A-3
to of this part. If this option is selected, the site-specific
moisture default value(s) must represent the fuel(s) or fuel blends
that are combusted in the unit during normal, stable operation, and
must account for any distinct difference(s) in the stack gas
moisture content associated with different process operating
conditions. At least nine Method 4 runs are required for
determining each site-specific default moisture percentage.
Calculate each site-specific default moisture value by taking the
arithmetic average of the Method 4 runs. Each site-specific
moisture default value shall be updated whenever the current value
is non-representative, due to changes in unit or process operation,
but in any event no less frequently than annually.
7.0 Reagents and Standards
7.1 Reference Gases. Reference gases (e.g., cylinder
gases or liquid evaporative standards) used to meet the
requirements of this PS must be NIST certified or NIST-traceable
and vendor certified to ±5.0 percent accuracy. HCl cylinder gases
must be certified according to Reference 5 in section 16 of this PS
through a documented unbroken chain of comparisons each
contributing to the reported uncertainty. Liquid evaporative
standards must be certified using the gravimetrically-based
procedures of the latest version of the EPA Traceability Protocol
for Qualification and Certification of Evaporative HCl Gas
Standards and Humidification of HCl Gas Standards from Cylinders
(see EPA-HQ-OAR-2013-0696-0026.pdf).
7.2 Cylinder gas and/or liquid evaporative standards must be
used within their certification periods.
7.3 High concentration cylinder gas or liquid evaporative HCl
standards may be diluted for use in this specification. You must
document the quantitative introduction of HCl standards into the
system using Method 205, found in 40 CFR part 51, appendix M, or
other procedure approved by the Administrator.
8.0 CEMS Measurement Location Specifications and Pretest
Preparation
8.1 Prior to the start of your initial PS tests, you must ensure
that the CEMS is installed according to the manufacturer's
specifications and the requirements in this section. You may use
either point or IP sampling technology.
8.2 CEMS Installation. Install the CEMS at an accessible
location where the pollutant concentration or emission rate
measurements are directly representative of the HCl emissions or
can be corrected so as to be representative of the total emissions
from the affected facility. The CEMS need not be installed at the
same location as the relative accuracy test location. If you fail
the RA requirements in this specification due to the CEMS
measurement location and a satisfactory correction technique cannot
be established, the Administrator may require the CEMS to be
relocated.
8.2.1 Single point sample gas extraction should be (1) no less
than 1.0 m (3.3 ft.) from the stack or duct wall or (2) within the
centroidal area of the stack or duct cross section.
8.2.2 IP-CEMS measurements should (1) be conducted totally
within the inner area bounded by a line 1.0 m (3.3 ft.) from the
stack or duct wall, (2) have at least 70 percent of the path within
the inner 50 percent of the stack or duct cross-sectional area, or
(3) be located over any part of the centroidal area.
8.2.2.1 You must measure the IP-CEMS path length from the inner
flange of the sampling ports or the inner end of the instrument
insertion into the stack cavity using a laser tape measure,
mechanical measurement tape, or similar device accurate to ±1.5 mm
(0.059 in).
8.2.2.2 You must ensure that any purge flow used to protect
IP-CEMS instrument windows from stack gas does not alter the
measurement path length. Purge flow of less than or equal to 10
percent of the gas velocity in the duct meets this requirement.
8.2.3 CEMS and Data Recorder Scale Check. After CEMS
installation, record and document the measurement range of the HCl
CEMS. The CEMS operating range and the range of the data recording
device must encompass all potential and expected HCl
concentrations, including the concentration equivalent to the
applicable emission limit and the span value.
9.0 Quality Control [Reserved] 10.0 Calibration and Standardization
[Reserved] 11.0 Performance Specification Test Procedure
After completing the CEMS installation, setup and calibration,
you must complete the PS test procedures in this section. You must
perform the following procedures and meet the performance
requirements for the initial demonstration of your CEMS:
a. Interference Test;
b. Beam Intensity Test (IP-CEMS only);
c. Temperature Verification Procedure (IP-CEMS only);
d. Pressure Verification Procedure (IP-CEMS only);
e. Level of Detection Determination;
f. Response Time Test;
g. Measurement Error Test;
h. Calibration Drift Test; and
i. Relative Accuracy Test.
11.1 Interference Test
11.1.1 Prior to its initial use in the field, you must
demonstrate that your monitoring system meets the performance
requirements of the interference test in section 13.5 to verify
that the candidate system measures HCl accurately in the presence
of common interferences in emission matrices.
11.1.2 Your interference test must be conducted in a controlled
environment. The equipment you test for interference must include
the combination of the analyzer, related analysis software, and any
sample conditioning equipment (e.g., dilution module,
moisture removal equipment or other interferent scrubber) used to
control interferents.
11.1.3 If you own multiple measurement systems with components
of the same make and model numbers, you need only perform this
interference test on one analyzer and associated interference
conditioning equipment combination. You may also rely on an
interference test conducted by the manufacturer or a continuous
measurement system integrator on a system having components of the
same make and model(s) of the system that you use.
11.1.4 Perform the interference check using an HCl reference gas
concentration of approximately five times the LOD.
11.1.5 Introduce the interference test gases listed in Table 1
in section 17.0 of this PS to the analyzer/conditioning system
separately or in any combination. The interference test gases need
not be of reference gas quality.
11.1.5.1 For extractive CEMS, the interference test gases may be
introduced directly into the inlet to the analyzer/conditioning
system after the probe extension coupling.
11.1.5.2 For IP-CEMS, the interference test gases may be added
with the HCl in a calibration cell or separately in a
temperature-controlled cell. The effective concentration of the gas
in the cell must meet the requirements in Table 1 corrected for
absolute pressure, temperature and the nominal stack sampling path
length of the CEMS.
11.1.6 The interference test must be performed by combining an
HCl reference gas with each interference test gas (or gas mixture).
You must measure the baseline HCl response, followed by the
response after adding the interference test gas(es) while
maintaining a constant HCl concentration. You must perform each
interference gas injection and evaluation in triplicate.
Note:
The baseline HCl gas may include interference gases at
concentrations typical of ambient air (e.g., 21 percent O2,
400 parts per million (ppm) CO2, 2 percent H2O), but these
concentrations must be brought to the concentrations listed in
Table 1 when their interference effects are being evaluated.
11.1.7 You should document the gas volume/rate, temperature, and
pressure used to conduct the interference test. A gas blending
system or manifold may be used.
11.1.8 Ensure the duration of each interference test is
sufficient to condition the HCl measurement system surfaces before
a stable measurement is obtained.
11.1.9 Measure the HCl response of the analyzer/sample
conditioning system combination to the test gases in ppmv. Record
the responses and determine the overall interference response using
Table 2 in section 17.0.
11.1.10 For each interference gas (or mixture), calculate the
mean difference (ΔMCavg) between the measurement system responses
with and without the interference test gas(es) using Equation 1 in
section 12.2. Summarize the results following the format contained
in Table 2 in section 17.
11.1.11 Calculate the percent interference (I) for the gas runs
using Equation 2 in section 12.2.
11.1.12 The total interference response (i.e., the sum of
the interference responses of all tested gaseous components) must
not exceed the criteria set forth in section 13.5 of this PS.
11.2 Beam Intensity Test for IP-CEMS
11.2.1 For IP-CEMS, you must establish the tolerance of your
system to beam intensity attenuation.
11.2.1.1 Your beam intensity test may be conducted in either a
controlled environment or on-site during initial setup and
demonstration of your CEMS.
11.2.1.2 If you have multiple measurement systems with
components of the same make and model numbers, you need only
perform this attenuation check on one system and you may also rely
on an attenuation test conducted by the manufacturer on a system
having components of the same make and model(s) of the system that
you use.
11.2.2 Insert one or more neutral density filter(s) or otherwise
attenuate the beam intensity by a known percentage (e.g., 90
percent of the beam intensity).
11.2.3 Perform a high-level HCl reference gas measurement.
11.2.4 Record and report the attenuated beam intensity, the
measured HCl calibration gas concentration at full beam intensity,
the measured HCl gas concentration with attenuated beam intensity,
and the percent difference between the two HCl measurements with
and without attenuation of the beam intensity. The percent
difference must not exceed the criteria set forth in section 13.6
of this PS.
11.2.5 In the future, you may not operate your IP-CEMS at a beam
intensity lower than that established based on the attenuation used
during this test. However, you may repeat the test to establish a
lower beam intensity limit or level.
11.3 Temperature Measurement Verification Procedure for IP-CEMS
11.3.1 Any measurement instrument or device that is used as a
reference in verification of temperature measurement must have an
accuracy that is traceable to NIST.
11.3.2 You must verify the temperature sensor used in IP-CEMS
measurements on-site as part of the initial installation and
verification procedures.
11.3.3 Comparison to Calibrated Temperature Measurement
Device.
11.3.3.1 Place the sensor of a calibrated temperature reference
device adjacent to the sensor used to measure stack temperature for
your IP-CEMS. The calibrated temperature reference device must
satisfy the accuracy requirements specified in Table 3 of this PS.
The calibrated temperature reference device must also have a range
equal to or greater than the range of your IP-CEMS temperature
sensor.
11.3.3.2 Allow sufficient time for the response of the
calibrated temperature reference device to reach equilibrium. With
the process and control device operating under normal conditions,
concurrently record the temperatures measured by your IP-CEMS
system (Mt) and the calibrated temperature reference device (Vt).
You must meet the accuracy requirements specified in section 13.7
of this PS.
11.3.3.3 If your IP-CEMS temperature sensor does not satisfy the
accuracy requirement of this PS, check all system components and
take any corrective action that is necessary to achieve the
required minimum accuracy. Repeat this verification procedure until
the accuracy requirement of this specification is satisfied.
11.4 Pressure Measurement Verification Procedure for IP-CEMS
11.4.1 For stack pressure measurement verification, you must
select a NIST-traceable gauge or monitor that conforms to the
design requirements of ASME B40.100-2010, “Pressure Gauges and
Gauge Attachments,” (incorporated by reference - see § 60.17) as a
reference device.
11.4.2 As an alternative for a calibrated pressure reference
device with NIST-traceable accuracy, you may use a water-in-glass
U-tube manometer to verify your IP-CEMS pressure measurement
equipment, provided there is also an accurate measurement of
absolute atmospheric pressure at the manometer location.
11.4.3 Allow sufficient time for the response of the reference
pressure measurement device to reach equilibrium. With the process
and control device operating under normal conditions, concurrently
record the pressures measured by your IP-CEMS system (MP) and the
pressure reference device (Vp). You must meet the accuracy
requirements specified in section 13.8 of this PS.
11.4.4 If your IP-CEMS pressure sensor does not satisfy the
accuracy requirement of this PS, check all system components and
take any corrective action that is necessary to achieve the
required minimum accuracy. Repeat this verification procedure until
the accuracy requirement of this specification is satisfied.
11.5 Level of Detection Determination
11.5.1 You must determine the minimum amount of HCl that can be
detected above the background in a representative gas matrix.
11.5.2 You must perform the LOD determination in a controlled
environment such as a laboratory or manufacturer's facility.
11.5.3 You must add interference gases listed in Table 1 of this
PS to a constant concentration of HCl reference gas.
11.5.3.1 You may not use an effective reference HCl gas
concentration greater than five times the estimated instrument
LOD.
11.5.3.2 For extractive CEMS, inject the HCl and interferents
described in section 11.1.5 directly into the inlet to the
analyzer.
11.5.3.3 For IP-CEMS, the HCl and interference test gases may be
added to a calibration cell or separately in a
temperature-controlled cell that is part of the measurement path.
The effective concentration of the gas in the cell must meet the
requirements in Table 1 corrected for absolute pressure,
temperature and the nominal stack sampling path length of the
CEMS.
11.5.4 Collect seven or more consecutive measurements separated
by twice the RT (described in section 11.6) to determine the
LOD.
11.5.5 Calculate the standard deviation of the measured values
and define the LOD as three times the standard deviation of these
measurements.
11.5.5.1 The LOD for extractive units must be determined and
reported in ppmv.
11.5.5.2 The LOD for IP units must be determined and reported on
a ppm-meter basis and the site- or installation-specific LOD must
be calculated based on the actual measurement path length and gas
density of the emissions at the specific site installation in
ppmv.
11.5.6 You must verify the controlled environment LOD of section
11.5.2 of this PS for your CEMS during initial setup and field
certification testing. You must use the SA procedure in appendix A
of this PS with the following exceptions:
11.5.6.1 For the LOD verification in the field, you must make
three independent SA measurements spiking the native source
concentration by no more than three times the controlled
environment LOD concentration determined in section 11.5.5.
11.5.6.2 For extractive CEMS, you must perform the SA as a
dynamic spike by passing the spiked source gas sample through all
filters, scrubbers, conditioners and other monitoring system
components used during normal sampling, and as much of the sampling
probe as practical. For IP-CEMS, you must perform the SA procedure
by adding or passing a known concentration reference gas into a
calibration cell in the optical path of the CEMS; you must also
include the source measurement optical path while performing the SA
measurement.
11.5.6.3 The amount detected, or standard addition response
(SAR), is based on the average difference of the native HCl
concentration in the stack or duct relative to the native stack
concentration plus the SA. You must be able to detect the effective
spike addition (ESA) above the native HCl present in the stack gas
matrix. For extractive CEMS, the ESA is calculated using Equation
A7 in appendix A of this PS. For IP-CEMS, the ESA is calculated as
Ci,eff using Equation 4 of this PS.
11.5.6.4 For extractive CEMS, calculate the SAR using Equation
A4 in appendix A of this PS. For IP-CEMS, calculate the SAR using
Equation A8.
11.5.6.5 If your system LOD field verification does not
demonstrate a SAR greater than or equal to your initial controlled
environment LOD, you must increase the SA concentration
incrementally and repeat the field verification procedure until the
SAR is equal to or greater than LOD. The site-specific standard
addition detection level (SADL) is equal to the standard addition
needed to achieve the acceptable SAR, and SADL replaces the
controlled environment LOD. For extractive CEMS, the SADL is
calculated as the ESA using Equation A7 in appendix A of this PS.
For IP-CEMS, the SADL is the SA calculated using Equation A8 in
appendix A of this PS. As described in section 13.1 of this PS, the
LOD or the SADL that replaces an LOD must be less than 20 percent
of the applicable emission limit.
11.6 Response Time Determination. You must determine ME-, LOD- and
SA-RT
11.6.1 For ME- or LOD-RT, start the upscale RT determination by
injecting zero gas into the measurement system as required by the
procedures in section 11.7 or 11.5, respectively. You may use
humidified zero gas. For standard addition RT, start the upscale RT
determination by measuring the native stack gas concentration of
HCl.
11.6.1.1 For extractive CEMS measuring ME- or LOD-RT, the output
has stabilized when there is no change greater than 1.0 percent of
full scale for 30 seconds.
11.6.1.2 For standard addition RT that includes the stack gas
matrix the final stable response may continue to vary by more than
1 percent, but may be considered stable if the variability is
random and not continuously rising or falling.
11.6.2 When the CEMS output has stabilized, record the response
in ppmv and introduce an upscale (high level) or spike reference
gas as required by the relevant procedure.
11.6.3 Record the time (upscale RT) required to reach 95 percent
of the change to the final stable value.
11.6.4 Next, for ME or LOD RT, reintroduce the zero gas and
record the time required to reach 95 percent of the change to the
stable instrument response at the zero gas reading. For SA RT,
introduce zero gas to the IP-CEMS cell or stop the spike gas flow
to the extractive CEMS as required by the specified procedure and
record the time required to reach 95 percent of the change to the
stable instrument response of the native gas reading. This time is
the downscale RT.
(Note: For CEMS that perform a series of operations (purge, blow
back, sample integration, analyze, etc.), you must start adding
reference or zero gas immediately after these procedures are
complete.)
11.6.5 Repeat the entire procedure until you have three sets of
data, then determine the mean upscale and mean downscale RTs for
each relevant procedure. Report the greater of the average upscale
or average downscale RTs as the RT for the system.
11.7 Measurement Error (ME) Test
11.7.1 On the same day and as close in time as practicable to
when the ME test is conducted, perform and meet requirements for a
calibration drift (CD) test using a zero gas as used in the
Seven-Day Drift Test (see section 11.8) and document and report the
results. To meet this requirement, the ME test may be conducted
during the Seven-Day CD Test.
11.7.2 Extractive CEMS ME Test.
11.7.2.1 Introduce reference gases to the CEMS probe, prior to
the sample conditioning and filtration system.
11.7.2.2 Measure three upscale HCl reference gas concentrations
in the range shown in Table 4 of this PS.
11.7.2.3 Introduce the gases into the sampling probe with
sufficient flow rate to replace the entire source gas sample.
11.7.2.4 Continue to add the reference gas until the response is
stable as evidenced when the difference between two consecutive
measurements is less than the LOD or within five percent of each
other.
11.7.2.5 Make triplicate measurements for each reference gas for
a total of nine measurements. Introduce different reference gas
concentrations in any order but do not introduce the same gas
concentration twice in succession.
11.7.2.6 At each reference gas concentration, determine the
average of the three CEMS responses (MCl). Calculate the ME using
Equation 3A in section 12.3.
11.7.2.7 If you desire to determine the system RT during this
test, you must inject zero gas immediately before and after each
injection of the high-level gas standard.
11.7.2.8 For non-dilution systems, you may adjust the system to
maintain the correct flow rate at the analyzer during the test, but
you may not make adjustments for any other purpose. For dilution
systems, you must operate the measurement system at the appropriate
dilution ratio during all system ME checks, and you may make only
the adjustments necessary to maintain the proper ratio.
11.7.3 IP-CEMS ME Test.
11.7.3.1 Conduct a 3-level system ME test by individually adding
the known concentrations of HCl reference gases into a calibration
cell of known volume, temperature, pressure and path length.
Note: The optical path used for IP-CEMS ME checks must
include the native HCl measurement path. You must also collect
native stack concentration HCl measurements before and after each
HCl standard measurement. Bracketing HCl reference gas measurements
with native stack HCl measurements must be used in the calculations
in Equation 5 in section 12.4.2 to correct the upscale measurements
for stack gas HCl concentration changes.
11.7.3.2 Introduce HCl reference gas into your calibration cell
in a range of concentrations that produce responses equivalent to
the source concentrations shown in Table 4 of this PS for your path
length.
11.7.3.3 Make triplicate measurements for each reference gas
standard for a total of nine measurements. Introduce different
calibration concentrations in any order but do not introduce the
same reference gas concentration twice in succession.
11.7.3.4 You must calculate the effective concentration (Ci,eff)
of the HCl reference gas equivalent to the stack concentration by
correcting for calibration cell temperature, pressure, path length,
line strength factor (LSF) and, if necessary, the native stack gas
HCl concentration using Equation 4 in section 12.0.
11.7.3.5 You may use the LSF provided by your instrument
manufacturer or determine an instrument-specific LSF as a function
of temperature using a heated gas cell and equivalent
concentrations (Ci,eff) between 50 and 150 percent of the emission
limit.
11.7.3.6 At each reference gas concentration, average the three
independent CEMS measurement responses corrected for native HCl
stack concentration. Calculate the ME using Equation 6A in section
12.4.3.
11.7.4 You may use Figure 1 in section 17.0 to record and report
your ME test results.
11.7.5 If the ME specification in section 13.3 is not met for
all three reference gas concentrations, take corrective action and
repeat the test until an acceptable 3-level ME test is
achieved.
11.8 Seven-Day Calibration Drift (CD) Test
11.8.1 The CD Test Period. Prior to the start of the RA tests,
you must perform a seven-day CD test. The purpose of the seven-day
CD test is to verify the ability of the CEMS to maintain
calibration for each of seven consecutive unit operating days as
specified in section 11.8.5 of this PS.
11.8.2 The CD tests must be performed using the zero gas and
mid-level reference gas standards as defined in Table 4 of this
PS.
11.8.3 Conduct the CD test on each day during continuous
operation of the CEMS and normal facility operations following the
procedures in section 11.7 of this PS, except that the zero gas and
mid-level gas need only be introduced to the measurement system
once each.
11.8.4 If periodic automatic or manual adjustments are made to
the CEMS zero and upscale response factor settings, conduct the CD
test immediately before these adjustments.
Note:
Automatic signal or mathematical processing of all measurement
data to determine emission results may be performed throughout the
entire CD process.
11.8.5 Determine the magnitude of the CD at approximately
24-hour intervals, for 7 consecutive unit operating days. The 7
consecutive unit operating days need not be 7 consecutive calendar
days.
11.8.6 Record the CEMS response for single measurements of zero
gas and mid-level reference gas. You may use Figure 2 in section 17
of this PS to record and report the results of your 7-day CD
test.
11.8.6.1 For extractive CEMS, calculate the CD using Equation 3B
in section 12.3. Report the absolute value of the differences as a
percentage of the span value.
11.8.6.2 For IP-CEMS, you must include the source measurement
optical path while performing the upscale CD measurement; you may
exclude the source measurement optical path when determining the
zero gas concentration. Calculate the CD for IP CEMS using
equations 4, 5, 6B, and 7 in section 12.4.
11.8.7 The zero-level and mid-level CD for each day must be less
than 5.0 percent of the span value as specified in section 13.2 of
this PS. You must meet this criterion for 7 consecutive operating
days.
11.8.8 Dynamic Spiking Option for Seven-Day CD Test. For
extractive CEMS, you have the option to conduct a mid-level dynamic
spiking procedure for each of the 7 days in lieu of the mid-level
reference gas injection described in sections 11.8.2 and 11.8.3. If
this option is selected, the daily zero CD check is still
required.
11.8.8.1 To conduct each of the seven daily mid-level dynamic
spikes, you must use the DS procedure described in appendix A of
this PS using a single spike of the mid-level reference gas
(see Table 4).
11.8.8.2 You must perform the dynamic spike procedure by passing
the spiked source gas sample through all filters, scrubbers,
conditioners and other monitoring system components used during
normal sampling, and as much of the sampling probe as
practical.
11.8.8.3 Calculate the mid-level CD as a percent of span using
Equation A6 of appendix A to this PS and calculate the zero drift
using Equation 3B in section 12.3. Record and report the results as
described in sections 11.8.6 and 11.8.7.
11.9 Relative Accuracy Test
11.9.1 Unless otherwise specified in an applicable regulation,
use Method 26A in 40 CFR part 60, appendix A-8, Method 320 in 40
CFR part 63, appendix A, or ASTM D6348-12 including all annexes, as
applicable, as the RMs for HCl measurement. Obtain and analyze RM
audit samples, if they are available, concurrently with RM test
samples according to the same procedure specified for performance
tests in the general provisions of the applicable part. If Method
26 is not specified in an applicable subpart of the regulations,
you may request approval to use Method 26 in appendix A-8 to this
part as the RM on a site-specific basis under §§ 63.7(f) or
60.8(b). Other RMs for moisture, O2, etc., may be necessary.
Conduct the RM tests in such a way that they will yield results
representative of the emissions from the source and can be compared
to the CEMS data.
11.9.1.1 When Method 26A is used as the RM, you must sample
sufficient gas to reach three times your method detection limit for
Method 26A in 40 CFR part 60, appendix A-8, or for a minimum of one
hour, whichever is greater.
11.9.1.2 When Method 320 or Method 321, both found in 40 CFR
part 63, appendix A, or ASTM D6348-12, are used as the RM, you must
collect gas samples that are at stack conditions (hot and wet) and
you must traverse as required in section 11.9.3.
11.9.2 Conduct the diluent (if applicable), moisture (if
needed), and pollutant measurements simultaneously. However,
diluent and moisture measurements that are taken within an hour of
the pollutant measurements may be used to calculate dry pollutant
concentration and emission rates.
11.9.3 Reference Method Measurement Location and Traverse
Point(s) Selection.
11.9.3.1 Measurement Location. Select, as appropriate, an
accessible RM measurement location at least two equivalent
diameters downstream from the nearest control device, point of
pollutant generation, or other point at which a change in the
pollutant concentration or emission rate may occur, and at least
one half equivalent diameter upstream from the effluent exhaust or
a control device. When pollutant concentration changes are due
solely to diluent leakage (e.g., air heater leakages) and
pollutants and diluents are simultaneously measured at the same
location, a half diameter may be used in lieu of two equivalent
diameters. The equivalent duct diameter is calculated according to
Method 1 in appendix A-1 to this part. The CEMS and RM sampling
locations need not be the same.
11.9.3.2 Traverse Point Selection. Select traverse points that
assure acquisition of representative RM samples over the stack or
duct cross section according to one of the following options: (a)
sample at twelve traverse points located according to section 11.3
of Method 1 in appendix A-1 to this part, (b) sample at 6 Method 1
traverse points according to section 6.5.6(b)(1) of appendix A to
part 75 of this chapter, or (c) sample at three points on a
measurement line (“3-point long line”) that passes through the
centroidal area of the duct in the direction of any potential
stratification. If this line interferes with the CEMS measurements,
you may displace the line up to 20 cm (12 in.) or 5.0 percent of
the equivalent diameter of the cross section, whichever is less,
from the centroidal area. Locate the three traverse points at 16.7,
50.0, and 83.3 percent of the measurement line. Alternatively, you
may conduct a stratification test following the procedures in
sections 11.9.3.2.1 through 11.9.3.2.4 to justify sampling at a
single point or three points located on the measurement line at
0.4, 1.2, and 2.0 m from the stack wall (“3-point short line”).
Stratification testing must be conducted at the sampling location
to be used for the RM measurements during the RA test and must be
made during normal facility operating conditions. You must evaluate
the stratification by measuring the gas on the same moisture basis
as the HCl CEMS (wet or dry). Stratification testing must be
repeated for each RA test program to justify single point or
“3-point short line” sampling.
11.9.3.2.1 Use a probe of appropriate length to measure the HCl
concentration or an alternative analyte, as described in this
section, using 12 traverse points located according to section 11.3
of Method 1 in appendix A-1 to 40 CFR part 60 for a circular stack
or nine points at the centroids of similarly-shaped, equal area
divisions of the cross section of a rectangular stack.
11.9.3.2.2 You may substitute a stratification test for SO2 for
the HCl stratification test. If you select this option, you must
follow the test procedures in Method 6C of appendix A-4 to 40 CFR
part 60 or Method 320 of appendix A of 40 CFR part 63.
11.9.3.2.3 Calculate the mean measured concentration for all
sampling points (MNavg).
11.9.3.2.4 Calculate the percent stratification (St) of each
traverse point using Equation 8 in section 12.5.
11.9.3.2.5 The gas stream is considered to be unstratified and
you may perform the RA testing at a single point that most closely
matches the mean if the concentration at each traverse point
differs from the mean concentration for all traverse points by: (a)
No more than 5.0 percent of the mean concentration; or (b) 0.2 ppm
(for HCl) or 3 ppm (for SO2) absolute, whichever is less
restrictive.
11.9.3.2.6 If the criterion for single point sampling (5.0
percent, 0.2 ppm for HCl or 3 ppm for SO2 are not met, but the
concentration at each traverse point differs from the mean
concentration for all traverse points by no more than 10.0 percent
of the mean, the gas stream is considered to be minimally
stratified, and you may take RA samples using the “3-point short
line”. Alternatively, you may use the 3-point short line if each
traverse point differs from the mean value by no more than 0.4 ppm
(for HCl) or 5 ppm (for SO2).
11.9.3.2.7 If the concentration at any traverse point differs
from the mean concentration by more than 10 percent, the gas stream
is considered stratified and you must sample using one of the
options in section 11.9.3.2 above.
11.9.3.3 Conduct all necessary RM tests within 3 cm (1.2 in.) of
the traverse points, but no closer than 3 cm (1.2 in.) to the stack
or duct wall.
11.9.4 In order to correlate the CEMS and RM data properly,
record the beginning and end of each RM run (including the time of
day in hours, minutes, and seconds) using a clock synchronized with
the CEM clock used to create a permanent time record with the CEMS
output.
11.9.5 You must conduct the RATA during representative process
and control operating conditions or as specified in an applicable
regulation, permit or subpart.
11.9.6 Conduct a minimum of nine RM test runs. NOTE: More
than nine RM test runs may be performed. If this option is chosen,
up to three test run results may be excluded so long as the total
number of test run results used to determine the CEMS RA is greater
than or equal to nine. However, all data must be reported including
the excluded test runs.
11.9.7 Analyze the results from the RM test runs using Equations
9-14 in section 12.6. Calculate the RA between the CEMS results and
the RM.
11.10 Record Keeping and Reporting
11.10.1 For systems that use a liquid evaporative standard
generator to deliver HCl reference gas standards, record supporting
data for these devices, including liquid feed calibrations, liquid
standard concentration(s) and NIST-traceability, feed rate and gas
flow calibrations for all diluent and HCl gas flows. All
calibrations must include a stated uncertainty, and the combined
uncertainty of the delivered HCl reference gas concentration must
be calculated and reported.
11.10.2 Record the results of the CD test, the RT test, the ME
test, the RA test, and for IP-CEMS, the results of the beam
intensity, temperature and pressure verification procedures. Also
keep records of the RM and CEMS field data, calculations, and
reference gas certifications necessary to confirm that the
performance of the CEMS met the performance specifications.
11.10.3 For systems that use Method 205 to prepare HCl reference
gas standards, record results of Method 205 performance test field
evaluation, reference gas certifications, and gas dilution system
calibration.
11.10.4 Record the LOD for the CEMS. For extractive CEMS, record
the LOD in ppmv. For IP-CEMS, record the LOD on a ppm-meter basis
along with a calculation of the installation specific LOD in ppmv.
For both CEMS types, you must also record the field verified
SADL.
11.10.5 Record the results of the interference test.
11.10.6 Report the results of all certification tests to the
appropriate regulatory agency (or agencies), in hardcopy and/or
electronic format, as required by the applicable regulation or
permit.
12.0 Calculations and Data Analysis 12.1 Nomenclature Ci =
Zero or HCl reference gas concentration used for test i (ppmv);
Ci,eff = Equivalent concentration of the reference gas value, Ci,
at the specified conditions (ppmv); CC = Confidence coefficient
(ppmv); CDextractive = Calibration drift for extractive CEMS
(percent); CDIP = Calibration drift for IP-CEMS (percent); CD0 =
Calibration drift at zero HCl concentrations for an IP-CEMS
(percent); davg = Mean difference between CEMS response and the
reference gas (ppmv); di = Difference of CEMS response and the RM
value (ppmv); I = Total interference from major matrix stack gases,
(percent); LSF = Line strength factor for IP-CEMS instrument
specific correction for temperature and gas matrix effects derived
from the HITRAN and/or manufacturer specific database (unitless);
ΔMCavg = Average of the 3 absolute values of the difference between
the measured HCl calibration gas concentrations with and without
interference from selected stack gases (ppmv); MCi = Measured HCl
reference gas concentration i (ppmv); MCi = Average of the measured
HCl reference gas concentration i (ppmv); MCint = Measured HCl
concentration of the HCl reference gas plus the individual or
combined interference gases (ppmv); MEextractive = Measurement
error for extractive CEMS (percent); MEIP = Measurement error for
IP-CEMS (percent); MNavg = Average concentration at all sampling
points (ppmv); MNbi = Measured native concentration bracketing each
calibration check measurement (ppmv); MNi = Measured native
concentration for test or run I (ppmv); n = Number of measurements
in an average value; Pstack = Absolute stack pressure (mm Hg)
Preference = Absolute pressure of the calibration cell for IP-CEMS
(mm Hg) PLCell = Path length of IP-CEMS calibration cell (m);
PLStack = Path length of IP-CEMS stack optical path (m); RA =
Relative accuracy of CEMS compared to a RM (percent); RMi = RM
concentration for test run i (ppmv); RMavg = Mean measured RM value
(ppmv); S = Span value (ppmv); Sd = Standard deviation of the
differences (ppmv); Sti = Stratification at traverse point i
(percent); SADL = Standard addition detection level (ppmv); t0.975
= One-sided t-value at the 97.5th percentile obtained from Table 5
in section 17.0 for n-1 measurements; Treference = Temperature of
the calibration cell for IP-CEMS (degrees Kelvin); Tstack =
Temperature of the stack at the monitoring location for IP-CEM
(degrees Kelvin).
12.2 Calculate the difference between the measured HCl
concentration with and without interferents for each interference
gas (or mixture) for your CEMS as:
Calculate the total percent interference as:
12.2.1 Calculate the equivalent concentration Ci,eff using
Equation 4:
12.3
Calculate the ME or CD at Concentration i for an Extractive CEMS
as: 12.4
Calculate the ME or CD at Concentration i for IP-CEMS That Use a
Calibration Cell as Follows:
12.4.1 Calculate the equivalent concentration Ci,eff using
Equation 4:
12.4.2 Calculate the average native concentration before and
after each calibration check measurement as:
12.4.3 Calculate the ME or CD at concentration i for an IP-CEM
as:
12.4.4 Calculate the zero CD as a percent of span for an IP-CEMS
as:
12.5
Calculate the Percent Stratification at Each Traverse Point as:
12.6
Calculate the RA Using RM and CEMS Data
12.6.1 Determine the CEMS final integrated minute average
pollutant concentration or emission rate for each RM test period.
Consider system RT, if important, and confirm that the results have
been corrected to the same moisture, temperature and diluent
concentration basis.
12.6.2 When Method 26A (or if approved for use, Method 26),
found in 40 CFR part 60, appendix A-8 of this part, is used as the
RM, compare each CEMS integrated average value against the
corresponding RM value for identical test periods. Make these
comparisons on the same basis (e.g., wet, dry, ppmv, or
units of the standard). To convert results generate by Method 26A
or 26 in mg/DSCM to ppmv, use the conversion factor 0.662
ppm/(mg/DSCM).
12.6.3 If the RM is Method 320 or Method 321, found in 40 CFR
part 63, appendix A, or ASTM D6348-12, make a direct comparison of
the average RM results and CEMS average value for identical test
periods.
12.6.4 For each test run, calculate the arithmetic difference of
the RM and CEMS results using Equation 9.
12.6.5 Calculate the standard deviation of the differences
(Sd) of the CEMS measured and RM results using Equation
10.
12.6.6 Calculate the confidence coefficient (CC) for the RATA
using Equation 11.
12.6.7 Calculate the mean difference (davg) between the
RM and CEMS values in the units of ppmv or the emission standard
using Equation 12.
12.6.8 Calculate the average RM value using Equation 13.
12.6.9 Calculate RA of the CEMS using Equation 14.
13.0
Method Performance
13.1 Level of Detection. You may not use a CEMS whose LOD or
SADL is greater than 20 percent of the applicable regulatory limit
or other action level for the intended use of the data.
13.2 Calibration Drift. The zero- and mid-level calibration
drift for the CEMS must not exceed 5.0 percent of the span value
for 7 consecutive operating days.
13.3 Measurement Error. The ME must be less than or equal to 5.0
percent of the span value at the low-, mid-, and high-level
reference gas concentrations.
13.4 Relative Accuracy. Unless otherwise specified in an
applicable regulation or permit, the RA of the CEMS, whether
calculated in units of HCl concentration or in units of the
emission standard, must be less than or equal to 20.0 percent of
the RM when RMavg is used in the denominator of Equation
14.
13.4.1 In cases where the RA is calculated on a concentration
(ppmv) basis, if the average RM emission level for the test is less
than 75 percent of the HCl concentration equivalent to the emission
standard, you may substitute the HCl concentration equivalent to
the standard in the denominator of Equation 14 in place of
RMavg.
13.4.2 Similarly, if the RA is calculated in units of the
emission standard and the HCl emission level measured by the RMs is
less than 75 percent of the emission standard, you may substitute
the emission standard in the denominator of Equation 14 in place of
RMavg.
13.4.3 The alternative calculated RA in paragraph 13.4.1 or
13.4.2 must be less than or equal to 15.0 percent.
13.5 Interference Test.
13.5.1 The sum of the interference response(s) from Equation 2
must not be greater than 2.5 percent of the calibration span or
±3.0 percent of the equivalent HCl concentration used for the
interference test, whichever is less restrictive. The results are
also acceptable if the sum of the interference response(s) does not
exceed six times the LOD or 0.5 ppmv for a calibration span of 5 to
10 ppm, or 0.2 ppmv for a calibration span of less than 5 ppmv.
13.6 IP-CEMS Beam Intensity Test. For IP-CEMS, the percent
difference between the measured concentration with and without
attenuation of the light source must not exceed ±3.0 percent.
13.7 IP-CEMS Temperature Measurement Verification. Your
temperature sensor satisfies the accuracy required if the absolute
relative difference between measured value of stack temperature
(Mt) and the temperature value from the calibrated temperature
reference device (Vt) is ≤1.0 percent or if the absolute difference
between Mt and Vt is ≤2.8 °C (5.0 °F), whichever is less
restrictive.
13.8 IP-CEMS Pressure Sensor Measurement Verification. Your
pressure sensor satisfies the accuracy required if the absolute
relative difference between the measured value of stack pressure
(MP) and the pressure value from the calibrated pressure reference
device (VP) is ≤5.0 percent or if the absolute difference between
Mp and VP is ≤0.12 kilopascals (0.5 inches of water column),
whichever is less restrictive.
1. Method 318 - Extractive FTIR Method for the Measurement of
Emissions From the Mineral Wool and Wool Fiberglass Industries, 40
CFR, part 63, subpart HHHHHHH, appendix A.
2. “EPA Protocol for the Use of Extractive Fourier Transform
Infrared (FTIR) Spectrometry in Analyses of Gaseous Emissions from
Stationary Industrial Sources,” February, 1995.
3. “Measurement of Gaseous Organic and Inorganic Emissions by
Extractive FTIR Spectroscopy,” EPA Contract No. 68-D2-0165, Work
Assignment 3-08.
4. “Method 301 - Field Validation of Pollutant Measurement
Methods from Various Waste Media,” 40 CFR part 63, appendix A.
5. EPA Traceability Protocol for Assay and Certification of
Gaseous Calibration Standards, U.S. Environmental Protection Agency
office of Research and Development, EPA/600/R-12/531, May 2012.
17.0 Tables, Diagrams, Flowcharts, and Validation Data
Table 1 - Interference Test Gas
Concentrations
Potential interferent gas
1
Approximate concentration
(balance N2)
CO2
15% ± 1% CO2.
2
CO
100 ± 20 ppm.
CH2O
20 ± 5 ppm.
CH4
100 ± 20 ppm.
NH3
10 ± 5 ppm (extractive CEMS
only).
NO
250 ± 50 ppm.
SO2
200 ± 20 ppm.
O2
3% ± 1% O2. 2
H2O
10% ± 1% H2O.
2
N2
Balance. 2
1 Any of these specific gases can
be tested at a lower level if the manufacturer has provided
reliable means for limiting or scrubbing that gas to a specified
level in CEMS field installations.
2 Gases for short path IP cell
interference tests cannot be added above 100 percent stack
equivalent concentration. Add these gases at the indicated
percentages to make up the remaining cell volume.
Table 3 - Design Standards for Temperature
Sensors
If the sensor is a . . .
You can use the following
design standards as guidance in selecting a sensor for your
IP-CEMS
1.
Thermocouple
a. ASTM E235-88 (1996),
“Specification for Thermocouples, Sheathed, Type K, for Nuclear or
Other High-Reliability Applications.”
b. ASTM E585/E585M-04,
“Specification for Compacted Mineral-Insulated, Metal-Sheathed,
Base Metal Thermocouple Cable.”
c. ASTM E608/E608M-06,
“Specification for Mineral-Insulated, Metal-Sheathed Base Metal
Thermocouples.”
d. ASTM E696-07,
“Specification for Tungsten-Rhenium Alloy Thermocouple Wire.”
e. ASTM E1129/E1129M-98
(2002), “Standard Specification for Thermocouple Connectors.”
f. ASTM E1159-98 (2003),
“Specification for Thermocouple Materials, Platinum-Rhodium Alloys,
and Platinum.”
g. ISA-MC96.1-1982,
“Temperature Measurement Thermocouples.”
2. Resistance
temperature detector
ASTM E1137/E1137M-04,
“Standard Specification for Industrial Platinum Resistance
Thermometers.”
Table 4 - Performance Specification Test
Zero and Reference Gas Ranges
Test
Units
HCl Zero and
Reference Gas Concentrations in Terms of Percent of Span
a
Section
Zero
Low Level
Mid Level
High Level
Calibration
Drift
% of Span
<LOD
NA
50-60 b
NA
11.8
Measurement
Error
% of Span
NA
20-30
50-60
80-100
11.7
a Reference gas concentration
must be NIST traceable. (see section 7.1)
b Mid-level is required. For DS
calibration drift option, choose a concentration that yields a
value in this range at the analyzer.
Table 5 - Student's t-Values
n-1 a
t-value
n-1 a
t-value
n-1 a
t-value
1
12.71
11
2.201
21
2.080
2
4.303
12
2.179
22
2.074
3
3.182
13
2.160
23
2.069
4
2.776
14
2.145
24
2.064
5
2.571
15
2.131
25
2.060
6
2.447
16
2.120
26
2.056
7
2.365
17
2.110
27
2.052
8
2.306
18
2.101
28
2.048
9
2.262
19
2.093
29
2.045
10
2.228
20
2.086
30
2.042
a The value n is the number of
independent pairs of measurements. Either discrete (independent)
measurements in a single run, or run averages can be used.
PS-18 Appendix A
Standard Addition Procedures 1.0 Scope and Application
1.1 This appendix to Performance Specification (PS) 18 describes
the procedure and performance requirements for standard addition
(SA) as a quality check for hydrogen chloride (HCl) continuous
emission monitoring systems (CEMS).
1.2 This appendix is applicable to quality checks of both
extractive and integrated path (IP) technologies used to measure
HCl emissions.
1.3 For extractive CEMS, this procedure must be used, as a level
of detection (LOD) verification of all field-installed CEMS.
Additionally, it is allowed by Procedure 6 in appendix F to this
part as an alternative to upscale calibration drift (CD) tests,
cylinder gas audits and relative accuracy audits (RAAs), and may be
used for quality assurance purposes under other applicable
regulations or permits that require HCl monitoring.
1.4 For IP-CEMS, this procedure must be used as a LOD
verification of all field-installed CEMS.
2.0 Summary of the Appendix for Standard Addition
As used here, SA is a gas phase method of standard additions
(either static or dynamic) used to verify the accuracy of CEMS
measurements in the presence of the sample matrix. For extractive
CEMS, it consists of spiking a known quantity of HCl dynamically
into the measurement system as an addition to the native HCl and
the native source gas matrix. For IP-CEMS, this procedure consists
of introducing a known quantity of HCl into the optical path that
also includes the native source gas.
3.0 Definitions. (See PS-18 and Procedure 6 of Appendix F to Part
60 for the Definitions Used in This Appendix.) 4.0
Interferences. Interferences are discussed in PS-18, section
4.0
5.0 Safety. The procedures required under this appendix
may involve hazardous materials, operations and equipment. This
procedure may not address all of the safety problems associated
with these procedures. You as the facility or operator must
establish appropriate safety and health practices and determine the
applicable regulatory limitations prior to performing these
procedures. As the CEMS user, you should consult instrument
operation manuals, material safety data sheets, compressed gas
safety requirements, and other Occupational Safety and Health
Administration regulations for specific precautions to be
taken.
6.0 Equipment and Supplies. An example of equipment and
supplies is described in section 6 of PS-18.
7.0 Reagents and Standards. SA materials must meet the
requirements defined for reference gases in section 7 of PS-18 to
perform this procedure with the following exception. You may use
gases certified by the gas vendor to ±5 percent to perform the
daily calibration drift assessment in section 4.1 of Procedure 6 in
appendix F of this part.
Note:
For extractive CEMS the concentrations of reference gases
required for SA are likely to be significantly higher than the
concentration of reference gases associated with PS-18
requirements.
8.0 Standard Addition and Dynamic Spiking Procedure. The
standard addition procedure consists of measuring the native source
gas concentration, addition of reference gas, and measurement of
the resulting SA elevated source gas concentration. For extractive
CEMS, HCl is spiked dynamically and thus, one must account for the
dilution of sample gas from the addition of the HCl reference gas.
For IP-CEMS, standard addition of an HCl reference gas is made by
either adding an HCl reference gas to a flow through cell or
inserting a sealed reference gas cell into the measurement path of
the CEMS. The enclosed cell or a fixed cell must contain an HCl
concentration that accounts for the difference in path length of
the cell used for SA relative to the measurement path.
8.1 SA Concentration and Measurement Replicates.
8.1.1 You must inject HCl gas to create a measured concentration
based on the requirements of the particular performance test
(e.g., LOD verification, CD, DSA).
8.1.2 Each dynamic spike (DS) or standard addition (SA)
replicate consists of a measurement of the source emissions
concentration of HCl (native stack concentration) with and without
the addition of HCl. With a single CEMS, you must alternate the
measurement of the native and SA-elevated source gas so that each
measurement of SA-elevated source gas is immediately preceded and
followed by a measurement of native stack gas. Introduce the SA
gases in such a manner that the entire CEMS is challenged.
Alternatively, you may use an independent continuous HCl monitor to
measure the native source concentration before and after each
standard addition as described in section 8.1.4.
8.1.3 Unless specified otherwise by an applicable rule, your
SA-elevated concentration may not exceed 100 percent of span when
the SA and native HCl concentration are combined.
8.1.4 As an alternative to making background measurements pre-
and post-SA, you may use an independent continuous HCl monitor as a
temporary unit to measure native stack HCl concentration while
simultaneously using the CEMS to measure the SA-elevated source
concentration. If you use an independent continuous HCl monitor you
must make one concurrent background or native HCl measurement using
both the installed CEMS and the independent continuous HCl monitor,
immediately before the SA procedure in section 8.2 or 8.3 begins,
to confirm that the independent monitoring system measures the same
background concentration as the CEMS being qualified with this
PS.
8.2 SA Procedure for Extractive CEMS (Dynamic Spiking)
8.2.1 Your HCl spike addition must not alter the total
volumetric sample system flow rate or basic dilution ratio of your
CEMS (if applicable).
8.2.2 Your spike gas flow rate must not contribute more than 10
percent of the total volumetric flow rate through the CEMS.
8.2.3 You must determine a dilution factor (DF) or relative
concentration of HCl for each dynamic spike. Calibrated,
NIST-traceable flow meters accurate to within 2.0 percent or highly
accurate tracer gas measurements are required to make the necessary
DF determinations at the accuracy required for this PS. Calibrated,
NIST-traceable flow meters (e.g., venturi, orifice) accurate
to within 2.0 percent should be recertified against an
NIST-traceable flow meter annually. Note: Since the spiking mass
balance calculation is directly dependent on the accuracy of the DF
determination, the accuracy of measurements required to determine
the total volumetric gas flow rate, spike gas flow rate, or tracer
gas standard addition concentration is critical to your ability to
accurately perform the DS procedure and calculate the results.
8.2.4 You must monitor and record the total sampling system flow
rate and sample dilution factor (DF) for the spiking and stack gas
sampling systems to ensure they are known and do not change during
the spiking procedure. Record all data on a data sheet similar to
Table A1 in section 13 of this appendix.
8.2.4.1 You may either measure the spike gas flow and the total
flow with calibrated flow meters capable of NIST traceable accuracy
to ±2.0 percent or calculate the flow using a stable tracer gas
included in your spike gas standard.
8.2.4.2 If you use flow measurements to determine the spike
dilution, then use Equation A1 in section 11.2.1 of this appendix
to calculate the DF. Determination of the spike dilution requires
measurement of HCl spike flow (Qspike) and total flow through the
CEM sampling system (Qprobe).
8.2.4.3 If your CEMS is capable of measuring an independent
stable tracer gas, you may use a spike gas that includes the tracer
to determine the DF using Equation A2 or A3 (sections 11.2.2 and
11.2.3 of this appendix) depending on whether the tracer gas is
also present in the native source emissions.
8.2.4.4 For extractive CEMS, you must correct the background
measurements of HCl for the dilution caused by the addition of the
spike gas standard. For spiking systems that alternate between
addition of HCl and zero gas at a constant DF, the background
measurements between spikes will not be equal to the native source
concentration.
8.2.5 Begin by collecting unspiked sample measurements of HCl.
You must use the average of two unspiked sample measurements as
your pre-spike background.
Note:
Measurements should agree within 5.0 percent or three times the
level of detection to avoid biasing the spike results.
8.2.5.1 Introduce the HCl gas spike into the permanent CEMS
probe, upstream of the particulate filter or sample conditioning
system and as close to the sampling inlet as practical.
8.2.5.2 Maintain the HCl gas spike for at least twice the DS
response time of your CEMS or until the consecutive measurements
agree within 5.0 percent. Collect two independent measurements of
the native plus spiked HCl concentration.
8.2.5.3 Stop the flow of spike gas for at least twice the DS
response time of your CEMS or until the consecutive measurements
agree within 5.0 percent. Collect two independent measurements of
the native HCl concentration.
8.2.6 Repeat the collection of sample measurements in section
8.2.5 until you have data for each spike concentration including a
final set of unspiked sample measurements according to section
8.2.5.3.
8.2.7 Verify that the CEMS responded as expected for each spike
gas injection, and that the data quality is not impacted by large
shifts in the native source concentration. Discard and repeat any
spike injections as necessary to generate a complete set of the
required replicate spike measurements.
8.2.8 Calculate the standard addition response (SAR) for
extractive CEMS, using Equation A4 in section 11.2, of this
appendix.
8.2.9 If the DS results do not meet the specifications for the
appropriate performance test in PS-18 or Procedure 6 of appendix F
of this part, you must take corrective action and repeat the DS
procedure.
8.3 SA Procedure for IP-CEMS (Static Spiking).
8.3.1 For IP-CEMS, you must make measurements of native source
gas HCl concentration and an HCl standard addition using a
calibration cell added to the optical measurement path.
8.3.2 Introduce zero gas into a calibration cell located in the
optical measurement path of the instrument. Continue to flush the
zero gas into the cell for at least the SA response time of your
CEMS or until two consecutive measurements taken are within 5.0
percent, then collect two independent measurements. Alternatively
you may measure native concentrations without the calibration cell
in the optical path.
8.3.3 Introduce the HCl spike gas into the calibration cell.
Continue to flush the spike gas into the cell for at least the SA
response time of your CEMS or until two consecutive measurements
taken are within 5.0 percent of one another. Then collect two
independent measurements of the SA addition to the native
concentration. Alternatively you may insert a sealed calibration
cell, containing HCl at the appropriate concentration, into the
optical path to measure the SA addition to the native
concentration.
8.3.4 Repeat the collection of SA-elevated and native HCl
measurements in sections 8.3.2 and 8.3.3 until you have data for
each SA concentration. Then, make a final native HCl measurement.
The measured concentrations must be corrected for calibration cell
and stack temperature, pressure and stack measurement path
length.
8.3.5 Calculate the standard addition response (SAR) for an
IP-CEMS, using Equation A8 in section 11.3 of this appendix.
8.3.6 If the SA results do not meet the specifications for the
appropriate performance test in PS-18 or Procedure 6 of appendix F
of this part, you must take corrective action and repeat the SA
procedure.
9.0 Quality Control [Reserved] 10.0 Calibration and Standardization
[Reserved]
11.0 Calculations and Data Analysis. Calculate the SA
response for each measurement and its associated native HCl
measurement(s), using equations in this section. (Note: For cases
where the emission standard is expressed in units of lb/MMBtu or
corrected to a specified O2 or CO2 concentration, an absolute
accuracy specification based on a span at stack conditions may be
calculated using the average concentration and applicable
conversion factors. The appropriate procedures for use in cases
where a percent removal standard is more restrictive than the
emission standard are the same as in 40 CFR part 60, PS-2, sections
12 and 13.)
11.1 Nomenclature.
Cspike = Actual HCl reference gas concentration spiked
(e.g., bottle or reference gas concentration) ppmv; Ctracer
spiked = Tracer gas concentration injected with spike gas
(“reference concentration”) ppmv; DF = Spiked gas dilution factor;
DSCD = Calibration drift determined using DS procedure (percent);
DSE = Dynamic spike error (ppmv); ESA = Effective spike addition
(ppmv); MCSA = Measured SA-elevated source gas concentration
(ppmv); MCspiked = Measured HCl reference gas concentration i
(ppmv); MCnative = Average measured concentration of the native HCl
(ppmv); Mnative tracer = Measured tracer gas concentration present
in native effluent gas (ppmv); Mspiked tracer = Measured diluted
tracer gas concentration in a spiked sample (ppmv); Qspike = Flow
rate of the dynamic spike gas (Lpm); Qprobe = Average total stack
sample flow through the system (Lpm); S = Span (ppmv); SAR =
Standard addition response (ppmv)
11.2 Calculating Dynamic Spike Response and Error for Extractive
CEMS.
11.2.1 If you determine your spike DF using spike gas and stack
sample flow measurements, calculate the DF using equation A1:
11.2.2 If you determine your spike DF using an independent
stable tracer gas that is not present in the native source
emissions, calculate the DF for DS using equation A2:
11.2.3 If you determine your spike dilution factor using an
independent stable tracer that is present in the native source
emissions, calculate the dilution factor for dynamic spiking using
equation A3:
11.2.4 Calculate the SA response using Equation A4:
11.2.5 Calculate the DS error using Equation A5.
11.2.6 Calculating CD using DS. When using the DS option for
determining mid-level CD, calculate the CD as a percent of span
using equation A6:
11.2.7 The effective spike addition (ESA) is the expected
increase in the measured concentration as a result of injecting a
spike. Calculate ESA using Equation A7:
11.3 Standard Addition Response for IP-CEMS. If you use an
IP-CEMS and a calibration cell, calculate the SA response using
Equation A8.
12.0
[Reserved] 13. Tables and Figures. [48 FR 13327, Mar.
30, 1983 and 48 FR 23611, May 25, 1983] Editorial Note:For Federal
Register citations affecting part 60, appendix B, see the List of
CFR Sections Affected, which appears in the Finding Aids section of
the printed volume and at www.govinfo.gov.
Appendix C to Part 60 - Determination of Emission Rate Change
40:9.0.1.1.1.0.1.1.10 : Appendix C
Appendix C to Part 60 - Determination of Emission Rate Change 1.
Introduction
1.1 The following method shall be used to determine whether a
physical or operational change to an existing facility resulted in
an increase in the emission rate to the atmosphere. The method used
is the Student's t test, commonly used to make inferences
from small samples.
2. Data
2.1 Each emission test shall consist of n runs (usually
three) which produce n emission rates. Thus two sets of
emission rates are generated, one before and one after the change,
the two sets being of equal size.
2.2 When using manual emission tests, except as provided in §
60.8(b) of this part, the reference methods of appendix A to this
part shall be used in accordance with the procedures specified in
the applicable subpart both before and after the change to obtain
the data.
2.3 When using continuous monitors, the facility shall be
operated as if a manual emission test were being performed. Valid
data using the averaging time which would be required if a manual
emission test were being conducted shall be used.
3. Procedure
3.1 Subscripts a and b denote prechange and postchange
respectively.
3.2 Calculate the arithmetic mean emission rate, E, for each set
of data using Equation 1.
Where: Ei = Emission rate for the
i th run. n = number of runs.
3.3 Calculate the sample variance, S2, for each set of
data using Equation 2.
3.4 Calculate the pooled estimate, Sp, using Equation
3.
3.5 Calculate the test statistic, t, using Equation
4.
4. Results
4.1 If Eb>,Ea and t>t′, where
t′ is the critical value of t obtained from Table 1,
then with 95% confidence the difference between Eb and
Ea is significant, and an increase in emission rate to the
atmosphere has occurred.
Table 1
Degrees of freedom
(na=nb−2)
t′ (95 percent confidence
level)
2
2.920
3
2.353
4
2.132
5
2.015
6
1.943
7
1.895
8
1.860
For greater than 8 degrees of freedom, see any standard statistical
handbook or text.
5.1 Assume the two performance tests produced the following set
of data:
5.6 Since (n 1 + n 2 − 2) = 4, t′ = 2.132
(from Table 1). Thus since t>t′ the difference in
the values of Ea and Eb is significant, and there has
been an increase in emission rate to the atmosphere.
6. Continuous Monitoring Data
6.1 Hourly averages from continuous monitoring devices, where
available, should be used as data points and the above procedure
followed.
[40 FR 58420, Dec. 16, 1975]
Appendix D to Part 60 - Required Emission Inventory Information
40:9.0.1.1.1.0.1.1.11 : Appendix D
Appendix D to Part 60 - Required Emission Inventory Information
(a) Completed NEDS point source form(s) for the entire plant
containing the designated facility, including information on the
applicable criteria pollutants. If data concerning the plant are
already in NEDS, only that information must be submitted which is
necessary to update the existing NEDS record for that plant. Plant
and point identification codes for NEDS records shall correspond to
those previously assigned in NEDS; for plants not in NEDS, these
codes shall be obtained from the appropriate Regional Office.
(b) Accompanying the basic NEDS information shall be the
following information on each designated facility:
(1) The state and county identification codes, as well as the
complete plant and point identification codes of the designated
facility in NEDS. (The codes are needed to match these data with
the NEDS data.)
(2) A description of the designated facility including, where
appropriate:
(i) Process name.
(ii) Description and quantity of each product (maximum per hour
and average per year).
(iii) Description and quantity of raw materials handled for each
product (maximum per hour and average per year).
(iv) Types of fuels burned, quantities and characteristics
(maximum and average quantities per hour, average per year).
(v) Description and quantity of solid wastes generated (per
year) and method of disposal.
(3) A description of the air pollution control equipment in use
or proposed to control the designated pollutant, including:
(i) Verbal description of equipment.
(ii) Optimum control efficiency, in percent. This shall be a
combined efficiency when more than one device operates in series.
The method of control efficiency determination shall be indicated
(e.g., design efficiency, measured efficiency, estimated
efficiency).
(iii) Annual average control efficiency, in percent, taking into
account control equipment down time. This shall be a combined
efficiency when more than one device operates in series.
(4) An estimate of the designated pollutant emissions from the
designated facility (maximum per hour and average per year). The
method of emission determination shall also be specified (e.g.,
stack test, material balance, emission factor).
[40 FR 53349, Nov. 17, 1975]
Appendix E to Part 60 [Reserved]
40:9.0.1.1.1.0.1.1.12 : Appendix E
Appendix E to Part 60 [Reserved]
Appendix F to Part 60 - Quality Assurance Procedures
40:9.0.1.1.1.0.1.1.13 : Appendix F
Appendix F to Part 60 - Quality Assurance Procedures Procedure 1.
Quality Assurance Requirements for Gas Continuous Emission
Monitoring Systems Used for Compliance Determination 1.
Applicability and Principle
1.1 Applicability. Procedure 1 is used to evaluate the
effectiveness of quality control (QC) and quality assurance (QA)
procedures and the quality of data produced by any continuous
emission monitoring system (CEMS) that is used for determining
compliance with the emission standards on a continuous basis as
specified in the applicable regulation. The CEMS may include
pollutant (e.g., S02 and N0x) and diluent (e.g., 02 or C02)
monitors.
This procedure specifies the minimum QA requirements necessary
for the control and assessment of the quality of CEMS data
submitted to the Environmental Protection Agency (EPA). Source
owners and operators responsible for one or more CEMS's used for
compliance monitoring must meet these minimum requirements and are
encouraged to develop and implement a more extensive QA program or
to continue such programs where they already exist.
Data collected as a result of QA and QC measures required in
this procedure are to be submitted to the Agency. These data are to
be used by both the Agency and the CEMS operator in assessing the
effectiveness of the CEMS QC and QA procedures in the maintenance
of acceptable CEMS operation and valid emission data.
Appendix F, Procedure 1 is applicable December 4, 1987. The
first CEMS accuracy assessment shall be a relative accuracy test
audit (RATA) (see section 5) and shall be completed by March 4,
1988 or the date of the initial performance test required by the
applicable regulation, whichever is later.
1.2 Principle. The QA procedures consist of two distinct and
equally important functions. One function is the assessment of the
quality of the CEMS data by estimating accuracy. The other function
is the control and improvement of the quality of the CEMS data by
implementing QC policies and corrective actions. These two
functions form a control loop: When the assessment function
indicates that the data quality is inadequate, the control effort
must be increased until the data quality is acceptable. In order to
provide uniformity in the assessment and reporting of data quality,
this procedure explicitly specifies the assessment methods for
response drift and accuracy. The methods are based on procedures
included in the applicable performance specifications (PS's) in
appendix B of 40 CFR part 60. Procedure 1 also requires the
analysis of the EPA audit samples concurrent with certain reference
method (RM) analyses as specified in the applicable RM's.
Because the control and corrective action function encompasses a
variety of policies, specifications, standards, and corrective
measures, this procedure treats QC requirements in general terms to
allow each source owner or operator to develop a QC system that is
most effective and efficient for the circumstances.
2. Definitions
2.1 Continuous Emission Monitoring System. The total equipment
required for the determination of a gas concentration or emission
rate.
2.2 Diluent Gas. A major gaseous constituent in a gaseous
pollutant mixture. For combustion sources, CO2 and O2 are the major
gaseous constituents of interest.
2.3 Span Value. The upper limit of a gas concentration
measurement range that is specified for affected source categories
in the applicable subpart of the regulation.
2.4 Zero, Low-Level, and High-Level Values. The CEMS response
values related to the source specific span value. Determination of
zero, low-level, and high-level values is defined in the
appropriate PS in appendix B of this part.
2.5 Calibration Drift (CD). The difference in the CEMS output
reading from a reference value after a period of operation during
which no unscheduled maintenance, repair or adjustment took place.
The reference value may be supplied by a cylinder gas, gas cell, or
optical filter and need not be certified.
2.6 Relative Accuracy (RA). The absolute mean difference between
the gas concentration or emission rate determined by the CEMS and
the value determined by the RM's plus the 2.5 percent error
confidence coefficient of a series of tests divided by the mean of
the RM tests or the applicable emission limit.
3. QC Requirements
Each source owner or operator must develop and implement a QC
program. As a minimum, each QC program must include written
procedures which should describe in detail, complete, step-by-step
procedures and operations for each of the following activities:
1. Calibration of CEMS.
2. CD determination and adjustment of CEMS.
3. Preventive maintenance of CEMS (including spare parts
inventory).
4. Data recording, calculations, and reporting.
5. Accuracy audit procedures including sampling and analysis
methods.
6. Program of corrective action for malfunctioning CEMS.
As described in section 5.2, whenever excessive inaccuracies
occur for two consecutive quarters, the source owner or operator
must revise the current written procedures or modify or replace the
CEMS to correct the deficiency causing the excessive
inaccuracies.
These written procedures must be kept on record and available
for inspection by the enforcement agency.
4. CD Assessment
4.1 CD Requirement. As described in 40 CFR 60.13(d), source
owners and operators of CEMS must check, record, and quantify the
CD at two concentration values at least once daily (approximately
24 hours) in accordance with the method prescribed by the
manufacturer. The CEMS calibration must, as minimum, be adjusted
whenever the daily zero (or low-level) CD or the daily high-level
CD exceeds two times the limits of the applicable PS's in appendix
B of this regulation.
4.2 Recording Requirement for Automatic CD Adjusting Monitors.
Monitors that automatically adjust the data to the corrected
calibration values (e.g., microprocessor control) must be
programmed to record the unadjusted concentration measured in the
CD prior to resetting the calibration, if performed, or record the
amount of adjustment.
4.3 Criteria for Excessive CD. If either the zero (or low-level)
or high-level CD result exceeds twice the applicable drift
specification in appendix B for five, consecutive, daily periods,
the CEMS is out-of-control. If either the zero (or low-level) or
high-level CD result exceeds four times the applicable drift
specification in appendix B during any CD check, the CEMS is
out-of-control. If the CEMS is out-of-control, take necessary
corrective action. Following corrective action, repeat the CD
checks.
4.3.1 Out-Of-Control Period Definition. The beginning of the
out-of-control period is the time corresponding to the completion
of the fifth, consecutive, daily CD check with a CD in excess of
two times the allowable limit, or the time corresponding to the
completion of the daily CD check preceding the daily CD check that
results in a CD in excess of four times the allowable limit. The
end of the out-of-control period is the time corresponding to the
completion of the CD check following corrective action that results
in the CD's at both the zero (or low-level) and high-level
measurement points being within the corresponding allowable CD
limit (i.e., either two times or four times the allowable limit in
appendix B).
4.3.2 CEMS Data Status During Out-of-Control Period. During the
period the CEMS is out-of-control, the CEMS data may not be used in
calculating emission compliance nor be counted towards meeting
minimum data availability as required and described in the
applicable subpart [e.g., § 60.47a(f)].
4.4 Data Recording and Reporting. As required in § 60.7(d) of
this regulation (40 CFR part 60), all measurements from the CEMS
must be retained on file by the source owner for at least 2 years.
However, emission data obtained on each successive day while the
CEMS is out-of-control may not be included as part of the minimum
daily data requirement of the applicable subpart [e.g., §
60.47a(f)] nor be used in the calculation of reported emissions for
that period.
5. Data Accuracy Assessment
5.1 Auditing Requirements. Each CEMS must be audited at least
once each calendar quarter. Successive quarterly audits shall occur
no closer than 2 months. The audits shall be conducted as
follows:
5.1.1 Relative Accuracy Test Audit (RATA). The RATA must be
conducted at least once every four calendar quarters, except as
otherwise noted in section 5.1.4 of this appendix. Conduct the RATA
as described for the RA test procedure in the applicable PS in
appendix B (e.g., PS 2 for SO2 and NOX). In addition, analyze the
appropriate performance audit samples received from EPA as
described in the applicable sampling methods (e.g., Methods 6 and
7).
5.1.2 Cylinder Gas Audit (CGA). If applicable, a CGA may be
conducted in three of four calendar quarters, but in no more than
three quarters in succession.
To conduct a CGA: (1) Challenge the CEMS (both pollutant and
diluent portions of the CEMS, if applicable) with an audit gas of
known concentration at two points within the following ranges:
Audit point
Audit range
Pollutant
monitors
Diluent monitors
for -
CO2
O2
1
20 to 30% of span value
5 to 8% by volume
4 to 6% by volume.
2
50 to 60% of span value
10 to 14% by volume
8 to 12% by volume.
Introduce each of the audit gases, three times each for a total
of six challenges. Introduce the gases in such a manner that the
entire CEMS is challenged. Do not introduce the same gas
concentration twice in succession.
Use of separate audit gas cylinder for audit points 1 and 2. Do
not dilute gas from audit cylinder when challenging the CEMS.
The monitor should be challenged at each audit point for a
sufficient period of time to assure adsorption-desorption of the
CEMS sample transport surfaces has stabilized.
(2) Operate each monitor in its normal sampling mode, i.e., pass
the audit gas through all filters, scrubbers, conditioners, and
other monitor components used during normal sampling, and as much
of the sampling probe as is practical. At a minimum, the audit gas
should be introduced at the connection between the probe and the
sample line.
(3) Use Certified Reference Materials (CRM's) (See Citation 1)
audit gases that have been certified by comparison to National
Institute of Standards and Technology (NIST) Standard Reference
Materials (SRM's) or EPA Protocol Gases following the most recent
edition of the EPA Traceability Protocol for Assay and
Certification of Gaseous Calibration Standards (See Citation 2).
Procedures for preparation of CRM's are described in Citation 1.
Procedures for preparation of EPA Protocol Gases are described in
Citation 2. In the case that a suitable audit gas level is not
commercially available, Method 205 (See Citation 3) may be used to
dilute CRM's or EPA Protocol Gases to the needed level. The
difference between the actual concentration of the audit gas and
the concentration indicated by the monitor is used to assess the
accuracy of the CEMS.
5.1.3 Relative Accuracy Audit (RAA). The RAA may be conducted
three of four calendar quarters, but in no more than three quarters
in succession. To conduct a RAA, follow the procedure described in
the applicable PS in appendix B for the relative accuracy test,
except that only three sets of measurement data are required.
Analyses of EPA performance audit samples are also required.
The relative difference between the mean of the RM values and
the mean of the CEMS responses will be used to assess the accuracy
of the CEMS.
5.1.4 Other Alternative Audits. Other alternative audit
procedures may be used as approved by the Administrator for three
of four calendar quarters. One RATA is required at least every four
calendar quarters, except in the case where the affected facility
is off-line (does not operate) in the fourth calendar quarter since
the quarter of the previous RATA. In that case, the RATA shall be
performed in the quarter in which the unit recommences operation.
Also, cylinder gas audits are not be required for calendar quarters
in which the affected facility does not operate.
5.2 Excessive Audit Inaccuracy. If the RA, using the RATA, CGA,
or RAA exceeds the criteria in section 5.2.3, the CEMS is
out-of-control. If the CEMS is out-of-control, take necessary
corrective action to eliminate the problem. Following corrective
action, the source owner or operator must audit the CEMS with a
RATA, CGA, or RAA to determine if the CEMS is operating within the
specifications. A RATA must always be used following an
out-of-control period resulting from a RATA. The audit following
corrective action does not require analysis of EPA performance
audit samples. If audit results show the CEMS to be out-of-control,
the CEMS operator shall report both the audit showing the CEMS to
be out-of-control and the results of the audit following corrective
action showing the CEMS to be operating within specifications.
5.2.1 Out-Of-Control Period Definition. The beginning of the
out-of-control period is the time corresponding to the completion
of the sampling for the RATA, RAA, or CGA. The end of the
out-of-control period is the time corresponding to the completion
of the sampling of the subsequent successful audit.
5.2.2 CEMS Data Status During Out-Of-Control Period. During the
period the monitor is out-of-control, the CEMS data may not be used
in calculating emission compliance nor be counted towards meeting
minimum data availabilty as required and described in the
applicable subpart [e.g., § 60.47a(f)].
5.2.3 Criteria for Excessive Audit Inaccuracy. Unless specified
otherwise in the applicable subpart, the criteria for excessive
inaccuracy are:
(1) For the RATA, the allowable RA in the applicable PS in
appendix B.
(2) For the CGA, ±15 percent of the average audit value or ±5
ppm, whichever is greater; for diluent monitors, ±15 percent of the
average audit value.
(3) For the RAA, ±15 percent of the three run average or ±7.5
percent of the applicable standard, whichever is greater.
5.3 Criteria for Acceptable QC Procedure. Repeated excessive
inaccuracies (i.e., out-of-control conditions resulting from the
quarterly audits) indicates the QC procedures are inadequate or
that the CEMS is incapable of providing quality data. Therefore,
whenever excessive inaccuracies occur for two consective quarters,
the source owner or operator must revise the QC procedures (see
section 3) or modify or replace the CEMS.
6. Calculations for CEMS Data Accuracy
6.1 RATA RA Calculation. Follow the equations described in
section 8 of appendix B, PS 2 to calculate the RA for the RATA. The
RATA must be calculated in units of the applicable emission
standard (e.g., ng/J).
6.2 RAA Accuracy Calculation. Use the calculation procedure in
the relevant performance specification to calculate the accuracy
for the RAA. The RAA must be calculated in the units of the
applicable emission standard.
6.3 CGA Accuracy Calculation. Use Equation 1-1 to calculate the
accuracy for the CGA, which is calculated in units of the
appropriate concentration (e.g., ppm SO2 or percent O2). Each
component of the CEMS must meet the acceptable accuracy
requirement.
where:
A = Accuracy of the CEMS, percent.
Cm = Average CEMS response during audit in units of applicable
standard or appropriate concentration.
Ca = Average audit value (CGA certified value or three-run
average for RAA) in units of applicable standard or appropriate
concentration.
6.4 Example Accuracy Calculations. Example calculations for the
RATA, RAA, and CGA are available in Citation 3.
7. Reporting Requirements
At the reporting interval specified in the applicable
regulation, report for each CEMS the accuracy results from section
6 and the CD assessment results from section 4. Report the drift
and accuracy information as a Data Assessment Report (DAR), and
include one copy of this DAR for each quarterly audit with the
report of emissions required under the applicable subparts of this
part.
As a minimum, the DAR must contain the following
information:
1. Source owner or operator name and address.
2. Identification and location of monitors in the CEMS.
3. Manufacturer and model number of each monitor in the
CEMS.
4. Assessment of CEMS data accuracy and date of assessment as
determined by a RATA, RAA, or CGA described in section 5 including
the RA for the RATA, the A for the RAA or CGA, the RM results, the
cylinder gases certified values, the CEMS responses, and the
calculations results as defined in section 6. If the accuracy audit
results show the CEMS to be out-of-control, the CEMS operator shall
report both the audit results showing the CEMS to be out-of-control
and the results of the audit following corrective action showing
the CEMS to be operating within specifications.
5. Results from EPA performance audit samples described in
section 5 and the applicable RM's.
6. Summary of all corrective actions taken when CEMS was
determined out-of-control, as described in sections 4 and 5.
An example of a DAR format is shown in Figure 1.
8. Bibliography
1. “A Procedure for Establishing Traceability of Gas Mixtures to
Certain National Bureau of Standards Standard Reference Materials.”
Joint publication by NBS and EPA-600/7-81-010, Revised 1989.
Available from the U.S. Environmental Protection Agency. Quality
Assurance Division (MD-77). Research Triangle Park, NC 27711.
2. “EPA Traceability Protocol For Assay And Certification Of
Gaseous Calibration Standards.” EPA-600/R-97/121, September 1997.
Available from EPA's Emission Measurement Center at
http://www.epa.gov/ttn/emc.
3. Method 205, “Verification of Gas Dilution Systems for Field
Instrument Calibrations,” 40 CFR 51, appendix M.
Figure 1 - Example Format for Data Assessment Report Period ending
date Year Company name Plant name Source unit no. CEMS manufacturer
Model no. CEMS serial no. CEMS type (e.g., in situ) CEMS sampling
location (e.g., control device outlet) CEMS span values as per the
applicable regulation: ______ (e.g., SO2 ____ ppm, NOX ____ ppm).
________
I. Accuracy assessment results (Complete A, B, or C below for
each CEMS or for each pollutant and diluent analyzer, as
applicable.) If the quarterly audit results show the CEMS to be
out-of-control, report the results of both the quarterly audit and
the audit following corrective action showing the CEMS to be
operating properly.
A. Relative accuracy test audit (RATA) for ____ (e.g., SO2 in
ng/J).
1. Date of audit ____.
2. Reference methods (RM's) used ____ (e.g., Methods 3 and
6).
3. Average RM value ____ (e.g., ng/J, mg/dsm 3, or percent
volume).
4. Average CEMS value ____.
5. Absolute value of mean difference [d] ____.
6. Confidence coefficient [CC] ____.
7. Percent relative accuracy (RA) ____ percent.
8. EPA performance audit results:
a. Audit lot number (1) ____ (2) ____
b. Audit sample number (1) ____ (2) ____
c. Results (mg/dsm 3) (1) ____ (2) ____
d. Actual value (mg/dsm 3)* (1) ____ (2) ____
e. Relative error* (1) ____ (2) ____
B. Cylinder gas audit (CGA) for ____ (e.g., SO2 in ppm).
Audit point 1
Audit point 2
1. Date of
audit
2. Cylinder ID
number
3. Date of
certification
4. Type of
certification
(e.g., EPA Protocol 1 or
CRM).
5. Certified audit
value
(e.g., ppm).
6. CEMS response
value
(e.g., ppm).
7. Accuracy
percent.
C. Relative accuracy audit (RAA) for ____ (e.g., SO2 in
ng/J).
1. Date of audit ____.
2. Reference methods (RM's) used ____ (e.g., Methods 3 and
6).
3. Average RM value ____ (e.g., ng/J).
4. Average CEMS value ____.
5. Accuracy ____ percent.
6. EPA performance audit results:
a. Audit lot number (1) ____ (2) ____
b. Audit sample number (1) ____ (2) ____
c. Results (mg/dsm 3) (1) ____ (2) ____
d. Actual value (mg/dsm 3) *(1) ____ (2)
e. Relative error* (1) ____ (2) ____
* To be completed by the Agency.
D. Corrective action for excessive inaccuracy.
1. Out-of-control periods.
a. Date(s) ____.
b. Number of days ____.
2. Corrective action taken
3. Results of audit following corrective action. (Use format of
A, B, or C above, as applicable.)
II. Calibration drift assessment.
A. Out-of-control periods.
1. Date(s) ____.
2. Number of days ____.
B. Corrective action taken Procedure 2 - Quality Assurance
Requirements for Particulate Matter Continuous Emission Monitoring
Systems at Stationary Sources 1.0 What Are the Purpose and
Applicability of Procedure 2?
The purpose of Procedure 2 is to establish the minimum
requirements for evaluating the effectiveness of quality control
(QC) and quality assurance (QA) procedures and the quality of data
produced by your particulate matter (PM) continuous emission
monitoring system (CEMS). Procedure 2 applies to PM CEMS used for
continuously determining compliance with emission standards or
operating permit limits as specified in an applicable regulation or
permit. Other QC procedures may apply to diluent (e.g., O2)
monitors and other auxiliary monitoring equipment included with
your CEMS to facilitate PM measurement or determination of PM
concentration in units specified in an applicable regulation.
1.1 What measurement parameter does Procedure 2 address?
Procedure 2 covers the instrumental measurement of PM as defined by
your source's applicable reference method (no Chemical Abstract
Service number assigned).
1.2 For what types of devices must I comply with Procedure 2?
You must comply with Procedure 2 for the total equipment that:
(1) We require you to install and operate on a continuous basis
under the applicable regulation, and
(2) You use to monitor the PM mass concentration associated with
the operation of a process or emission control device.
1.3 What are the data quality objectives (DQOs) of Procedure 2?
The overall DQO of Procedure 2 is the generation of valid,
representative data that can be transferred into useful information
for determining PM CEMS concentrations averaged over a prescribed
interval. Procedure 2 is also closely associated with Performance
Specification 11 (PS-11).
(1) Procedure 2 specifies the minimum requirements for
controlling and assessing the quality of PM CEMS data submitted to
us or the delegated permitting authority.
(2) You must meet these minimum requirements if you are
responsible for one or more PM CEMS used for compliance monitoring.
We encourage you to develop and implement a more extensive QA
program or to continue such programs where they already exist.
1.4 What is the intent of the QA/QC procedures specified in
Procedure 2? Procedure 2 is intended to establish the minimum QA/QC
requirements for PM CEMS and is presented in general terms to allow
you to develop a program that is most effective for your
circumstances. You may adopt QA/QC procedures that go beyond these
minimum requirements to ensure compliance with applicable
regulations.
1.5 When must I comply with Procedure 2? You must comply with
the basic requirements of Procedure 2 immediately following
successful completion of the initial correlation test of PS-11.
2.0 What Are the Basic Requirements of Procedure 2?
Procedure 2 requires you to perform periodic evaluations of PM
CEMS performance and to develop and implement QA/QC programs to
ensure that PM CEMS data quality is maintained.
2.1 What are the basic functions of Procedure 2?
(1) Assessment of the quality of your PM CEMS data by estimating
measurement accuracy;
(2) Control and improvement of the quality of your PM CEMS data
by implementing QC requirements and corrective actions until the
data quality is acceptable; and
(3) Specification of requirements for daily instrument zero and
upscale drift checks and daily sample volume checks, as well as
routine response correlation audits, absolute correlation audits,
sample volume audits, and relative response audits.
3.0 What Special Definitions Apply to Procedure 2?
The definitions in Procedure 2 include those provided in PS-11
of Appendix B, with the following additions:
3.1 “Absolute Correlation Audit (ACA)” means an evaluation of
your PM CEMS response to a series of reference standards covering
the full measurement range of the instrument (e.g., 4 mA to
20 mA).
3.2 “Correlation Range” means the range of PM CEMS responses
used in the complete set of correlation test data.
3.3 “PM CEMS Correlation” means the site-specific relationship
(i.e., a regression equation) between the output from your
PM CEMS (e.g., mA) and the particulate concentration, as
determined by the reference method. The PM CEMS correlation is
expressed in the same units as the PM concentration measured by
your PM CEMS (e.g., mg/acm). You must derive this relation
from PM CEMS response data and manual reference method data that
were gathered simultaneously. These data must be representative of
the full range of source and control device operating conditions
that you expect to occur. You must develop the correlation by
performing the steps presented in sections 12.2 and 12.3 of
PS-11.
3.4 “Reference Method Sampling Location” means the location in
your source's exhaust duct from which you collect manual reference
method data for developing your PM CEMS correlation and for
performing relative response audits (RRAs) and response correlation
audits (RCAs).
3.5 “Response Correlation Audit (RCA)” means the series of tests
specified in section 10.3(8) of this procedure that you conduct to
ensure the continued validity of your PM CEMS correlation.
3.6 “Relative Response Audit (RRA)” means the brief series of
tests specified in section 10.3(6) of this procedure that you
conduct between consecutive RCAs to ensure the continued validity
of your PM CEMS correlation.
3.7 “Sample Volume Audit (SVA)” means an evaluation of your PM
CEMS measurement of sample volume if your PM CEMS determines PM
concentration based on a measure of PM mass in an extracted sample
volume and an independent determination of sample volume.
4.0 Interferences [Reserved] 5.0 What Do I Need To Know To Ensure
the Safety of Persons Using Procedure 2?
People using Procedure 2 may be exposed to hazardous materials,
operations, and equipment. Procedure 2 does not purport to address
all of the safety issues associated with its use. It is your
responsibility to establish appropriate safety and health practices
and determine the applicable regulatory limitations before
performing this procedure. You must consult your CEMS user's manual
for specific precautions to be taken with regard to your PM CEMS
procedures.
6.0 What Equipment and Supplies Do I Need? [Reserved] 7.0 What
Reagents and Standards Do I Need?
You will need reference standards or procedures to perform the
zero drift check, the upscale drift check, and the sample volume
check.
7.1 What is the reference standard value for the zero drift
check? You must use a zero check value that is no greater than 20
percent of the PM CEMS's response range. You must obtain
documentation on the zero check value from your PM CEMS
manufacturer.
7.2 What is the reference standard value for the upscale drift
check? You must use an upscale check value that produces a response
between 50 and 100 percent of the PM CEMS's response range. For a
PM CEMS that produces output over a range of 4 mA to 20 mA, the
upscale check value must produce a response in the range of 12 mA
to 20 mA. You must obtain documentation on the upscale check value
from your PM CEMS manufacturer.
7.3 What is the reference standard value for the sample volume
check? You must use a reference standard value or procedure that
produces a sample volume value equivalent to the normal sampling
rate. You must obtain documentation on the sample volume value from
your PM CEMS manufacturer.
8.0 What Sample Collection, Preservation, Storage, and Transport
Are Relevant to This Procedure? [Reserved] 9.0 What Quality Control
Measures Are Required by This Procedure for My PM CEMS?
You must develop and implement a QC program for your PM CEMS.
Your QC program must, at a minimum, include written procedures that
describe, in detail, complete step-by-step procedures and
operations for the activities in paragraphs (1) through (8) of this
section.
(1) Procedures for performing drift checks, including both zero
drift and upscale drift and the sample volume check (see sections
10.2(1), (2), and (5)).
(2) Methods for adjustment of PM CEMS based on the results of
drift checks, sample volume checks (if applicable), and the
periodic audits specified in this procedure.
(3) Preventative maintenance of PM CEMS (including spare parts
inventory and sampling probe integrity).
(4) Data recording, calculations, and reporting.
(5) RCA and RRA procedures, including sampling and analysis
methods, sampling strategy, and structuring test conditions over
the prescribed range of PM concentrations.
(6) Procedures for performing ACAs and SVAs and methods for
adjusting your PM CEMS response based on ACA and SVA results.
(7) Program of corrective action for malfunctioning PM CEMS,
including flagged data periods.
(8) For extractive PM CEMS, procedures for checking extractive
system ducts for material accumulation.
9.1 What QA/QC documentation must I have? You are required to
keep the written QA/QC procedures on record and available for
inspection by us, the State, and/or local enforcement agency for
the life of your CEMS or until you are no longer subject to the
requirements of this procedure.
9.2 How do I know if I have acceptable QC procedures for my PM
CEMS? Your QC procedures are inadequate or your PM CEMS is
incapable of providing quality data if you fail two consecutive QC
audits (i.e., out-of-control conditions resulting from the
annual audits, quarterly audits, or daily checks). Therefore, if
you fail the same two consecutive audits, you must revise your QC
procedures or modify or replace your PM CEMS to correct the
deficiencies causing the excessive inaccuracies (see section 10.4
for limits for excessive audit inaccuracy).
10.0 What Calibration/Correlation and Standardization Procedures
Must I Perform for My PM CEMS?
You must generate a site-specific correlation for each of your
PM CEMS installation(s) relating response from your PM CEMS to
results from simultaneous PM reference method testing. The PS-11
defines procedures for developing the correlation and defines a
series of statistical parameters for assessing acceptability of the
correlation. However, a critical component of your PM CEMS
correlation process is ensuring the accuracy and precision of
reference method data. The activities listed in sections 10.1
through 10.10 assure the quality of the correlation.
10.1 When should I use paired trains for reference method
testing? Although not required, we recommend that you should use
paired-train reference method testing to generate data used to
develop your PM CEMS correlation and for RCA testing. Guidance on
the use of paired sampling trains can be found in the PM CEMS
Knowledge Document (see section 16.5 of PS-11).
10.2 What routine system checks must I perform on my PM CEMS?
You must perform routine checks to ensure proper operation of
system electronics and optics, light and radiation sources and
detectors, and electric or electro-mechanical systems. Necessary
components of the routine system checks will depend on design
details of your PM CEMS. As a minimum, you must verify the system
operating parameters listed in paragraphs (1) through (5) of this
section on a daily basis. Some PM CEMS may perform one or more of
these functions automatically or as an integral portion of unit
operations; for other PM CEMS, you must initiate or perform one or
more of these functions manually.
(1) You must check the zero drift to ensure stability of your PM
CEMS response to the zero check value. You must determine system
output on the most sensitive measurement range when the PM CEMS is
challenged with a zero reference standard or procedure. You must,
at a minimum, adjust your PM CEMS whenever the daily zero drift
exceeds 4 percent.
(2) You must check the upscale drift to ensure stability of your
PM CEMS response to the upscale check value. You must determine
system output when the PM CEMS is challenged with a reference
standard or procedure corresponding to the upscale check value. You
must, at a minimum, adjust your PM CEMS whenever the daily upscale
drift check exceeds 4 percent.
(3) For light-scattering and extinction-type PM CEMS, you must
check the system optics to ensure that system response has not been
altered by the condition of optical components, such as fogging of
lens and performance of light monitoring devices.
(4) You must record data from your automatic drift-adjusting PM
CEMS before any adjustment is made. If your PM CEMS automatically
adjusts its response to the corrected calibration values
(e.g., microprocessor control), you must program your PM
CEMS to record the unadjusted concentration measured in the drift
check before resetting the calibration. Alternately, you may
program your PM CEMS to record the amount of adjustment.
(5) For extractive PM CEMS that measure the sample volume and
use the measured sample volume as part of calculating the output
value, you must check the sample volume on a daily basis to verify
the accuracy of the sample volume measuring equipment. This sample
volume check must be done at the normal sampling rate of your PM
CEMS. You must adjust your PM CEMS sample volume measurement
whenever the daily sample volume check error exceeds 10
percent.
10.3 What are the auditing requirements for my PM CEMS? You must
subject your PM CEMS to an ACA and an SVA, as applicable, at least
once each calendar quarter. Successive quarterly audits must occur
no closer than 2 months apart. You must conduct an RCA and an RRA
at the frequencies specified in the applicable regulation or
facility operating permit. An RRA or RCA conducted during any
calendar quarter can take the place of the ACA required for that
calendar quarter. An RCA conducted during the period in which an
RRA is required can take the place of the RRA for that period.
(1) When must I perform an ACA? You must perform an ACA each
quarter unless you conduct an RRA or RCA during that same
quarter.
(2) How do I perform an ACA? You perform an ACA according to the
procedure specified in paragraphs (2)(i) through (v) of this
section.
(i) You must challenge your PM CEMS with an audit standard or an
equivalent audit reference to reproduce the PM CEMS's measurement
at three points within the following ranges:
Audit point
Audit range
1
0 to 20 percent of measurement
range
2
40 to 60 percent of
measurement range
3
70 to 100 percent of
measurement range
(ii) You must then challenge your PM CEMS three times at each
audit point and use the average of the three responses in
determining accuracy at each audit point. Use a separate audit
standard for audit points 1, 2, and 3. Challenge the PM CEMS at
each audit point for a sufficient period of time to ensure that
your PM CEMS response has stabilized.
(iii) Operate your PM CEMS in the mode, manner, and range
specified by the manufacturer.
(iv) Store, maintain, and use audit standards as recommended by
the manufacturer.
(v) Use the difference between the actual known value of the
audit standard and the response of your PM CEMS to assess the
accuracy of your PM CEMS.
(3) When must I perform an SVA? You must perform an audit of the
measured sample volume (e.g., the sampling flow rate for a
known time) once per quarter for applicable PM CEMS with an
extractive sampling system. Also, you must perform and pass an SVA
prior to initiation of any of the reference method data collection
runs for an RCA or RRA.
(4) How do I perform an SVA? You perform an SVA according to the
procedure specified in paragraphs (4)(i) through (iii) of this
section.
(i) You perform an SVA by independently measuring the volume of
sample gas extracted from the stack or duct over each batch cycle
or time period with a calibrated device. You may make this
measurement either at the inlet or outlet of your PM CEMS, so long
as it measures the sample gas volume without including any dilution
or recycle air. Compare the measured volume with the volume
reported by your PM CEMS for the same cycle or time period to
calculate sample volume accuracy.
(ii) You must make measurements during three sampling cycles for
batch extractive monitors (e.g., Beta-gauge) or during three
periods of at least 20 minutes for continuous extractive PM
CEMS.
(iii) You may need to condense, collect, and measure moisture
from the sample gas prior to the calibrated measurement device
(e.g., dry gas meter) and correct the results for moisture
content. In any case, the volumes measured by the calibrated device
and your PM CEMS must be on a consistent temperature, pressure, and
moisture basis.
(5) How often must I perform an RRA? You must perform an RRA at
the frequency specified in the applicable regulation or facility
operating permit. You may conduct an RCA instead of an RRA during
the period when the RRA is required.
(6) How do I perform an RRA? You must perform the RRA according
to the procedure specified in paragraphs (6)(i) and (ii) of this
section.
(i) You perform an RRA by collecting three simultaneous
reference method PM concentration measurements and PM CEMS
measurements at the as-found source operating conditions and PM
concentration.
(ii) We recommend that you use paired trains for reference
method sampling. Guidance on the use of paired sampling trains can
be found in the PM CEMS Knowledge Document (see section 16.5 of
PS-11).
(7) How often must I perform an RCA? You must perform an RCA at
the frequency specified in the applicable regulation or facility
operating permit.
(8) How do I perform an RCA? You must perform the RCA according
to the procedures for the PM CEMS correlation test described in
PS-11, section 8.6, except that the minimum number of runs required
is 12 in the RCA instead of 15 as specified in PS-11.
(9) What other alternative audits can I use? You can use other
alternative audit procedures as approved by us, the State, or local
agency for the quarters when you would conduct ACAs.
10.4 What are my limits for excessive audit inaccuracy? Unless
specified otherwise in the applicable subpart, the criteria for
excessive audit inaccuracy are listed in paragraphs (1) through (6)
of this section.
(1) What are the criteria for excessive zero or upscale drift?
Your PM CEMS is out of control if the zero drift check or upscale
drift check either exceeds 4 percent for five consecutive daily
periods or exceeds 8 percent for any one day.
(2) What are the criteria for excessive sample volume
measurement error? Your PM CEMS is out of control if sample volume
check error exceeds 10 percent for five consecutive daily periods
or exceeds 20 percent for any one day.
(3) What are the criteria for excessive ACA error? Your PM CEMS
is out of control if the results of any ACA exceed ±10 percent of
the average audit value, as calculated using Equation 2-1a, or 7.5
percent of the applicable standard, as calculated using Equation
2-1b, whichever is greater.
(4) What is the criterion for excessive SVA error? Your PM CEMS
is out of control if results exceed ±5 percent of the average
sample volume audit value.
(5) What are the criteria for passing a RCA? To pass a RCA, you
must meet the criteria specified in paragraphs (5)(i) and (ii) of
this section. If your PM CEMS fails to meet these RCA criteria, it
is out of control.
(i) For all 12 data points, the PM CEMS response value can be no
greater than the greatest PM CEMS response value used to develop
your correlation curve.
(ii) At least 75 percent of a minimum number of 12 sets of PM
CEMS and reference method measurements must fall within a specified
area on a graph of the correlation regression line. The specified
area on the graph of the correlation regression line is defined by
two lines parallel to the correlation regression line, offset at a
distance of ±25 percent of the numerical emission limit value from
the correlation regression line. If any of the PM CEMS response
values resulting from your RCA are lower than the lowest PM CEMS
response value of your existing correlation curve, you may extend
your correlation regression line to the point corresponding to the
lowest PM CEMS response value obtained during the RCA. This
extended correlation regression line must then be used to determine
if the RCA data meets this criterion.
(6) What are the criteria to pass a RRA? To pass a RRA, you must
meet the criteria specified in paragraphs (6)(i) and (ii) of this
section. If your PM CEMS fails to meet these RRA criteria, it is
out of control.
(i) For all three data points, the PM CEMS response value can be
no greater than the greatest PM CEMS response value used to develop
your correlation curve.
(ii) At least two of the three sets of PM CEMS and reference
method measurements must fall within the same specified area on a
graph of the correlation regression line as required for the RCA
and described in paragraph (5)(ii) of this section.
10.5 What do I do if my PM CEMS is out of control? If your PM
CEMS is out of control, you must take the actions listed in
paragraphs (1) and (2) of this section.
(1) You must take necessary corrective action to eliminate the
problem and perform tests, as appropriate, to ensure that the
corrective action was successful.
(i) Following corrective action, you must repeat the previously
failed audit to confirm that your PM CEMS is operating within the
specifications.
(ii) If your PM CEMS failed an RRA, you must take corrective
action until your PM CEMS passes the RRA criteria. If the RRA
criteria cannot be achieved, you must perform an RCA.
(iii) If your PM CEMS failed an RCA, you must follow procedures
specified in section 10.6 of this procedure.
(2) You must report both the audit showing your PM CEMS to be
out of control and the results of the audit following corrective
action showing your PM CEMS to be operating within
specifications.
10.6 What do I do if my PM CEMS fails an RCA? After an RCA
failure, you must take all applicable actions listed in paragraphs
(1) through (3) of this section.
(1) Combine RCA data with data from the active PM CEMS
correlation and perform the mathematical evaluations defined in
PS-11 for development of a PM CEMS correlation, including
examination of alternate correlation models (i.e., linear,
polynomial, logarithmic, exponential, and power). If the expanded
data base and revised correlation meet PS-11 statistical criteria,
use the revised correlation.
(2) If the criteria specified in paragraph (1) of this section
are not achieved, you must develop a new PM CEMS correlation based
on revised data. The revised data set must consist of the test
results from only the RCA. The new data must meet all requirements
of PS-11 to develop a revised PM CEMS correlation, except that the
minimum number of sets of PM CEMS and reference method measurements
is 12 instead of the minimum of 15 sets required by PS-11. Your PM
CEMS is considered to be back in controlled status when the revised
correlation meets all of the performance criteria specified in
section 13.2 of PS-11.
(3) If the actions in paragraphs (1) and (2) of this section do
not result in an acceptable correlation, you must evaluate the
cause(s) and comply with the actions listed in paragraphs (3)(i)
through (iv) of this section within 90 days after the completion of
the failed RCA.
(i) Completely inspect your PM CEMS for mechanical or
operational problems. If you find a mechanical or operational
problem, repair your PM CEMS and repeat the RCA.
(ii) You may need to relocate your PM CEMS to a more appropriate
measurement location. If you relocate your PM CEMS, you must
perform a new correlation test according to the procedures
specified in PS-11.
(iii) The characteristics of the PM or gas in your source's flue
gas stream may have changed such that your PM CEMS measurement
technology is no longer appropriate. If this is the case, you must
install a PM CEMS with measurement technology that is appropriate
for your source's flue gas characteristics. You must perform a new
correlation test according to the procedures specified in
PS-11.
(iv) If the corrective actions in paragraphs (3)(i) through
(iii) of this section were not successful, you must petition us,
the State, or local agency for approval of alternative criteria or
an alternative for continuous PM monitoring.
10.7 When does the out-of-control period begin and end? The
out-of-control period begins immediately after the last test run or
check of an unsuccessful RCA, RRA, ACA, SVA, drift check, or sample
volume check. The out-of-control period ends immediately after the
last test run or check of the subsequent successful audit or drift
check.
10.8 Can I use the data recorded by my PM CEMS during
out-of-control periods? During any period when your PM CEMS is out
of control, you may not use your PM CEMS data to calculate emission
compliance or to meet minimum data availability requirements
described in the applicable regulation.
10.9 What are the QA/QC reporting requirements for my PM CEMS?
You must report the accuracy results for your PM CEMS, specified in
section 10.4 of this procedure, at the interval specified in the
applicable regulation. Report the drift and accuracy information as
a Data Assessment Report (DAR), and include one copy of this DAR
for each quarterly audit with the report of emissions required
under the applicable regulation. An example DAR is provided in
Procedure 1, Appendix F of this part.
10.10 What minimum information must I include in my DAR? As a
minimum, you must include the information listed in paragraphs (1)
through (5) of this section in the DAR:
(1) Your name and address.
(2) Identification and location of monitors in your CEMS.
(3) Manufacturer and model number of each monitor in your
CEMS.
(4) Assessment of PM CEMS data accuracy/acceptability, and date
of assessment, as determined by an RCA, RRA, ACA, or SVA described
in section 10, including the acceptability determination for the
RCA or RRA, the accuracy for the ACA or SVA, the reference method
results, the audit standards, your PM CEMS responses, and the
calculation results as defined in section 12. If the accuracy audit
results show your PM CEMS to be out of control, you must report
both the audit results showing your PM CEMS to be out of control
and the results of the audit following corrective action showing
your PM CEMS to be operating within specifications.
(5) Summary of all corrective actions you took when you
determined your PM CEMS to be out of control, as described in
section 10.5, or after failing on RCA, as described in section
10.6.
10.7 Where and how long must I retain the QA data that this
procedure requires me to record for my PM CEMS? You must keep the
records required by this procedure for your PM CEMS onsite and
available for inspection by us, the State, and/or local enforcement
agency for a period of 5 years.
11.0 What Analytical Procedures Apply to This Procedure?
Sample collection and analysis are concurrent for this
procedure. You must refer to the appropriate reference method for
the specific analytical procedures.
12.0 What Calculations and Data Analysis Must I Perform for my PM
CEMS?
(1) How do I determine RCA and RRA acceptability? You must plot
each of your PM CEMS and reference method data sets from an RCA or
RRA on a graph based on your PM CEMS correlation line to determine
if the criteria in paragraphs 10.4(5) or (6), respectively, are
met.
(2) How do I calculate ACA accuracy? You must use either
Equation 2-1a or 2-1b to calculate ACA accuracy for each of the
three audit points. However, when calculating ACA accuracy for the
first audit point (0 to 20 percent of measurement range), you must
use Equation 2-1b to calculate ACA accuracy if the reference
standard value (Rv) equals zero.
Where: ACA Accuracy = The ACA accuracy at each
audit point, in percent, RCEM = Your PM CEMS response to the
reference standard, and RV = The reference standard value.
Where: ACA Accuracy = The ACA accuracy at each
audit point, in percent, CCEM = The PM concentration that
corresponds to your PM CEMS response to the reference standard, as
calculated using the correlation equation for your PM CEMS, CRV =
The PM concentration that corresponds to the reference standard
value in units consistent with CCEM, and Cs = The PM concentration
that corresponds to the applicable emission limit in units
consistent with CCEM.
(3) How do I calculate daily upscale and zero drift? You must
calculate the upscale drift using Equation 2-2 and the zero drift
using Equation 2-3:
Where: UD
= The upscale drift of your PM CEMS, in percent, RCEM = Your PM
CEMS response to the upscale check value, RU = The upscale check
value, and Rr = The response range of the analyzer. Where: ZD = The
zero (low-level) drift of your PM CEMS, in percent, RCEM = Your PM
CEMS response of the zero check value, RL = The zero check value,
and Rr = The response range of the analyzer.
(4) How do I calculate SVA accuracy? You must use Equation 2-4
to calculate the accuracy, in percent, for each of the three SVA
tests or the daily sample volume check:
Where:
SVA Accuracy = The SVA accuracy at each audit point, in percent, VM
= Sample gas volume determined/reported by your PM CEMS
(e.g., dscm), and VR = Sample gas volume measured by the
independent calibrated reference device (e.g., dscm) for the
SVA or the reference value for the daily sample volume check. Note:
Before calculating SVA accuracy, you must correct the sample gas
volumes measured by your PM CEMS and the independent calibrated
reference device to the same basis of temperature, pressure, and
moisture content. You must document all data and calculations.
13.0 Method Performance [Reserved] 14.0 Pollution Prevention
[Reserved] 15.0 Waste Management [Reserved] 16.0 Which References
are Relevant to This Method? [Reserved] 17.0 What Tables, Diagrams,
Flowcharts, and Validation Data Are Relevant to This Method?
[Reserved] Procedure 3 - Quality Assurance Requirements for
Continuous Opacity Monitoring Systems at Stationary Sources 1.0
What are the purpose and applicability of Procedure 3?
The purpose of Procedure 3 is to establish quality assurance and
quality control (QA/QC) procedures for continuous opacity
monitoring systems (COMS). Procedure 3 applies to COMS used to
demonstrate continuous compliance with opacity standards specified
in new source performance standards (NSPS) promulgated by EPA
pursuant to section 111(b) of the Clean Air Act, 42 U.S.C. 7411(b)
- Standards of Performance for New Stationary Sources.
1.1 What are the data quality objectives of Procedure 3?
The overall data quality objective (DQO) of Procedure 3 is the
generation of valid and representative opacity data. Procedure 3
specifies the minimum requirements for controlling and assessing
the quality of COMS data submitted to us or the delegated
regulatory agency. Procedure 3 requires you to perform periodic
evaluations of a COMS performance and to develop and implement
QA/QC programs to ensure that COMS data quality is maintained.
1.2 What is the intent of the QA/QC procedures specified in
Procedure 3? Procedure 3 is intended to establish the minimum
QA/QC requirements to verify and maintain an acceptable level of
quality of the data produced by COMS. It is presented in general
terms to allow you to develop a program that is most effective for
your circumstances.
1.3 When must I comply with Procedure 3? You must comply
with Procedure 3 no later than November 12, 2014.
2.0 What are the basic functions of Procedure 3?
The basic functions of Procedure 3 are assessment of the quality
of your COMS data and control and improvement of the quality of the
data by implementing QC requirements and corrective actions.
Procedure 3 provides requirements for:
(1) Daily instrument zero and upscale drift checks and status
indicators checks;
(2) Quarterly performance audits which include the following
assessments:
(i) Optical alignment,
(ii) Calibration error, and
(iii) Zero compensation.
Sources that achieve quality assured data for four consecutive
quarters may reduce their auditing frequency to semi-annual. If a
performance audit is failed, the source must resume quarterly
testing for that audit requirement until it again demonstrates
successful performance over four consecutive quarters.
(3) Annual zero alignment.
3.0 What special definitions apply to Procedure 3?
The definitions in Procedure 3 include those provided in
Performance Specification 1 (PS-1) of Appendix B of this part and
ASTM D6216-12 and the following additional definitions.
3.1 Out-of-control periods. Out-of-control periods mean
that one or more COMS parameters falls outside of the acceptable
limits established by this rule.
(1) Daily Assessments. Whenever the calibration drift
(CD) exceeds twice the specification of PS-1, the COMS is
out-of-control. The beginning of the out-of-control period is the
time corresponding to the completion of the daily calibration drift
check. The end of the out-of-control period is the time
corresponding to the completion of appropriate adjustment and
subsequent successful CD assessment.
(2) Quarterly and Annual Assessments. Whenever an annual
zero alignment or quarterly performance audit fails to meet the
criteria established in paragraphs (2) and (3) of section 10.4, the
COMS is out-of-control. The beginning of the out-of-control period
is the time corresponding to the completion of the performance
audit indicating the failure to meet these established criteria.
The end of the out-of-control period is the time corresponding to
the completion of appropriate corrective actions and the subsequent
successful audit (or, if applicable, partial audit).
4.0 What interferences must I avoid?
Opacity cannot be measured accurately in the presence of
condensed water vapor. Thus, COMS opacity compliance determinations
cannot be made when condensed water vapor is present, such as
downstream of a wet scrubber without a reheater or at other
saturated flue gas locations. Therefore, COMS must be located where
condensed water vapor is not present.
5.0 What do I need to know to ensure the safety of persons using
Procedure 3?
Those implementing Procedure 3 may be exposed to hazardous
materials, operations and equipment. Procedure 3 does not purport
to address all of the safety issues associated with its use. It is
your responsibility to establish appropriate health and safety
practices and determine the applicable regulatory limitations
before performing this procedure. You should consult the COMS
user's manual for specific precautions to take.
6.0 What equipment and supplies do I need?
The equipment and supplies that you need are specified in PS-1.
You are not required to purchase a new COMS if your existing COMS
meets the requirements specified in Procedure 3.
7.0 What reagents and standards do I need?
The reagents and standards that you need are specified in PS-1.
You are not required to purchase a new COMS if your existing COMS
meets the requirements specified in Procedure 3.
8.0 What sample collection, preservation, storage, and transport
are relevant to this procedure? [Reserved] 9.0 What quality control
measures are required by this procedure for my COMS?
You must develop and implement a QC program for your COMS. Your
QC program must, at a minimum, include written procedures which
describe in detail complete step-by-step procedures and operations
for the activities in paragraphs (1) through (4):
(1) Procedures for performing drift checks, including both zero
and upscale drift and the status indicators check,
(2) Procedures for performing quarterly performance audits,
(3) A means of checking the zero alignment of the COMS, and
(4) A program of corrective action for a malfunctioning COMS.
The corrective action must include, at a minimum, the requirements
specified in section 10.5.
9.1 What QA/QC documentation must I have? You are
required to keep the QA/QC written procedures required in section
9.0 on site and available for inspection by us, the state, and/or
local enforcement agencies.
9.2 What actions must I take if I fail QC audits? If you
fail two consecutive annual audits, two consecutive quarterly
audits, or five consecutive daily checks, you must either revise
your QC procedures or determine if your COMS is malfunctioning. If
you determine that your COMS is malfunctioning, you must take the
necessary corrective action as specified in section 10.5. If you
determine that your COMS requires extensive repairs, you may use a
substitute COMS provided the substitute meets the requirements in
section 10.6.
10.0 What calibration and standardization procedures must I perform
for my COMS?
(1) You must perform daily system checks to ensure proper
operation of system electronics and optics, light and radiation
sources and detectors, electric or electro-mechanical systems, and
general stability of the system calibration. Daily is defined as
any portion of a calendar day in which a unit operates.
(2) You must subject your COMS to a performance audit to include
checks of the individual COMS components and factors affecting the
accuracy of the monitoring data at least once per QA operating
quarter. A QA operating quarter is a calendar quarter in which a
unit operates at least 168 hours.
(3) At least annually, you must perform a zero alignment by
comparing the COMS simulated zero to the actual clear path zero.
Annually is defined as a period wherein the unit is operating at
least 28 days in a calendar year. The simulated zero device
produces a simulated clear path condition or low-level opacity
condition, where the energy reaching the detector is between 90 and
110 percent of the energy reaching the detector under actual clear
path conditions.
10.1 What daily system checks must I perform on my COMS?
The specific components required to undergo daily system checks
will depend on the design details of your COMS. At a minimum, you
must verify the system operating parameters listed in paragraphs
(1) through (3) of this section. Some COMS may perform one or more
of these functions automatically or as an integral portion of unit
operations; other COMS may perform one or more of these functions
manually.
(1) You must check the zero drift to ensure stability of your
COMS response to the simulated zero device. The simulated zero
device, an automated mechanism within the transmissometer that
produces a simulated clear path condition or low-level opacity
condition, is used to check the zero drift. You must, at a minimum,
take corrective action on your COMS whenever the daily zero drift
exceeds twice the applicable drift specification in section 13.3(6)
of PS-1.
(2) You must check the upscale drift to ensure stability of your
COMS response to the upscale drift value. The upscale calibration
device, an automated mechanism (employing an attenuator or reduced
reflectance device) within the transmissometer that produces an
upscale opacity value is used to check the upscale drift. You must,
at a minimum, take corrective action on your COMS whenever the
daily upscale drift check exceeds twice the applicable drift
specification in section 13.3(6) of PS-1.
(3) You must, at a minimum, check the status indicators, data
acquisition system error messages, and other system self-diagnostic
indicators. You must take appropriate corrective action based on
the manufacturer's recommendations when the COMS is operating
outside preset limits.
10.2 What are the quarterly auditing requirements for my
COMS? At a minimum, the parameters listed in paragraphs (1)
through (3) of this section must be included in the performance
audit conducted on a quarterly basis as defined in section
10.0(2).
(1) For units with automatic zero compensation, you must
determine the zero compensation for the COMS. The value of the zero
compensation applied at the time of the audit must be calculated as
equivalent opacity and corrected to stack exit conditions according
to the procedures specified by the manufacturer. The compensation
applied to the effluent by the monitor system must be recorded.
(2) You must conduct a three-point calibration error test of the
COMS. Three calibration attenuators, either primary or secondary
must meet the requirements of PS-1, with one exception. Instead of
recalibrating the attenuators semi-annually, they must be
recalibrated annually. If two annual calibrations agree within 0.5
percent opacity, the attenuators may then be calibrated once every
five years. The three attenuators must be placed in the COMS light
beam path for at least three nonconsecutive readings. All monitor
responses must then be independently recorded from the COMS
permanent data recorder. Additional guidance for conducting this
test is included in section 8.1(3)(ii) of PS-1. The low-, mid-, and
high-range calibration error results must be computed as the mean
difference and 95 percent confidence interval for the difference
between the expected and actual responses of the monitor as
corrected to stack exit conditions. The equations necessary to
perform the calculations are found in section 12.0 of PS-1. For the
calibration error test method, you must use the external audit
device. When the external audit device is installed, with no
calibration attenuator inserted, the COMS measurement reading must
be less than or equal to one percent opacity. You must also
document procedures for properly handling and storing the external
audit device and calibration attenuators within your written QC
program.
(3) You must check the optical alignment of the COMS in
accordance with the instrument manufacturer's recommendations. If
the optical alignment varies with stack temperature, perform the
optical alignment test when the unit is operating.
10.3 What are the annual auditing requirements for my
COMS?
(1) You must perform the primary zero alignment method under
clear path conditions. The COMS must be removed from its
installation and set up under clear path conditions. There must be
no adjustments to the monitor other than the establishment of the
proper monitor path length and correct optical alignment of the
COMS components. You must record the COMS response to a clear
condition and to the COMS's simulated zero condition as percent
opacity corrected to stack exit conditions. For a COMS with
automatic zero compensation, you must disconnect or disable the
zero compensation mechanism or record the amount of correction
applied to the COMS's simulated zero condition. The response
difference in percent opacity to the clear path and simulated zero
conditions must be recorded as the zero alignment error. You must
adjust the COMS's simulated zero device to provide the same
response as the clear path condition as specified in paragraph (3)
of section 10.0.
(2) As an alternative, monitors capable of allowing the
installation of an external zero device may use the device for the
zero alignment provided that: (1) The external zero device setting
has been established for the monitor path length and recorded for
the specific COMS by comparison of the COMS responses to the
installed external zero device and to the clear path condition, and
(2) the external zero device is demonstrated to be capable of
producing a consistent zero response when it is repeatedly (i.e.,
three consecutive installations and removals prior to conducting
the final zero alignment check) installed on the COMS. This can be
demonstrated by either the manufacturer's certificate of
conformance (MCOC) or actual on-site performance. The external zero
device setting must be permanently set at the time of initial
zeroing to the clear path zero value and protected when not in use
to ensure that the setting equivalent to zero opacity does not
change. The external zero device response must be checked and
recorded prior to initiating the zero alignment. If the external
zero device setting has changed, you must remove the COMS from the
stack in order to reset the external zero device. If you employ an
external zero device, you must perform the zero alignment audits
with the COMS off the stack at least every three years. If the
external zero device is adjusted within the three-year period, you
must perform the zero alignment with the COMS off the stack no
later than three years from the date of adjustment.
(3) The procedure in section 6.8 of ASTM D6216-12 is
allowed.
10.4 What are my limits for excessive audit inaccuracy?
Unless specified otherwise in the applicable subpart, the criteria
for excessive inaccuracy are listed in paragraphs (1) through
(4).
(1) What is the criterion for excessive zero or upscale drift?
Your COMS is out-of-control if either the zero drift check or
upscale drift check exceeds twice the applicable drift
specification in PS-1 for any one day.
(2) What is the criterion for excessive zero alignment? Your
COMS is out-of-control if the zero alignment error exceeds 2
percent opacity.
(3) What is the criterion to pass the quarterly performance
audit? Your COMS is out-of-control if the results of a quarterly
performance audit indicate noncompliance with the following
criteria:
(i) The optical alignment indicator does not show proper
alignment (i.e., does not fall within a specific reference mark or
condition).
(ii) The zero compensation exceeds 4 percent opacity, or
(iii) The calibration error exceeds 3 percent opacity.
(4) What is the criterion for data capture? You must adhere to
the data capture criterion specified in the applicable subpart.
10.5 What corrective action must I take if my COMS is
malfunctioning? You must have a corrective action program in
place to address the repair and/or maintenance of your COMS. The
corrective action program must address routine/preventative
maintenance and various types of analyzer repairs. The corrective
action program must establish what diagnostic testing must be
performed after each type of activity to ensure that the COMS is
collecting valid, quality-assured data. Recommended maintenance and
repair procedures and diagnostic testing after repairs may be found
in an associated guidance document.
10.6 What requirements must I meet if I use a temporary
opacity monitor?
(1) In the event that your certified opacity monitor has to be
removed for extended service, you may install a temporary
replacement monitor to obtain required opacity emissions data
provided that:
(i) The temporary monitor has been certified according to ASTM
D6216-12 for which a MCOC has been provided;
(ii) The use of the temporary monitor does not exceed 1080 hours
(45 days) of operation per year as a replacement for a fully
certified opacity monitor. After that time, the analyzer must
complete a full certification according to PS-1 prior to further
use as a temporary replacement monitor. Once a temporary
replacement monitor has been installed and required testing and
adjustments have been successfully completed, it cannot be replaced
by another temporary replacement monitor to avoid the full PS-1
certification testing required after 1080 hours (45 days) of
use;
(iii) The temporary monitor has been installed and successfully
completed an optical alignment assessment and status indicator
assessment;
(iv) The temporary monitor has successfully completed an
off-stack clear path zero assessment and zero calibration value
adjustment procedure;
(v) The temporary monitor has successfully completed an
abbreviated zero and upscale drift check consisting of seven zero
and upscale calibration value drift checks which may be conducted
within a 24-hour period with not more than one calibration drift
check every three hours and not less than one calibration drift
check every 25 hours. Calculated zero and upscale drift
requirements are the same as specified for the normal PS-1
certification;
(vi) The temporary monitor has successfully completed a
three-point calibration error test;
(vii) The upscale reference calibration check value of the new
monitor has been updated in the associated data recording
equipment;
(viii) The overall calibration of the monitor and data recording
equipment has been verified; and
(ix) The user has documented all of the above in the maintenance
log.
(2) Data generated by the temporary monitor is considered valid
when paragraphs (i) through (ix) in this section have been met.
10.7 When do out-of-control periods begin and end? The
out-of-control periods are as specified in section 3.1.
10.8 What are the limitations on the use of my COMS data
collected during out-of-control periods? During the period your
COMS is out-of-control, you may not use your COMS data to calculate
emission compliance or to meet minimum data capture requirements in
this procedure or the applicable regulation.
10.9 What are the QA/QC reporting requirements for my
COMS? You must report in a Data Assessment Report (DAR) the
information required by sections 10.0, 10.1, 10.2, and 10.3 for
your COMS at the interval specified in the applicable
regulation.
10.10 What minimum information must I include in my DAR?
At a minimum, you must include the information listed in paragraphs
(1) through (5) of this section in the DAR.
(1) Name of person completing the report and facility
address,
(2) Identification and location of your COMS(s),
(3) Manufacturer, model, and serial number of your COMS(s),
(4) Assessment of COMS data accuracy/acceptability and date of
assessment as determined by a performance audit described in
section 10.0. If the accuracy audit results show your COMS to be
out-of-control, you must report both the audit results showing your
COMS to be out-of-control and the results of the audit following
corrective action showing your COMS to be operating within
specifications, and
(5) Summary of all corrective actions you took when you
determined your COMS was out-of-control.
10.11 Where and how long must I retain the QA data that this
procedure requires me to record for my COMS? You must keep the
records required by this procedure for your COMS on site and
available for inspection by us, the state, and/or the local
enforcement agency for the period specified in the regulations
requiring the use of COMS.
11.0 What analytical procedures apply to this procedure? [Reserved]
12.0 What calculations and data analysis must I perform for my
COMS? The calculations required for the quarterly performance audit
are in section 12.0 of PS-1. 13.0 Method Performance [Reserved]
14.0 Pollution Prevention [Reserved] 15.0 Waste Management
[Reserved] 16.0 References
16.1 Performance Specification 1-Specifications and Test
Procedures for Continuous Opacity Monitoring Systems in Stationary
Sources, 40 CFR part 60, Appendix B.
16.2 ASTM D6216-12-Standard Practice for Opacity Monitor
Manufacturers to Certify Conformance with Design and Performance
Specifications, American Society for Testing and Materials
(ASTM).
17.0 What tables, diagrams, flowcharts, and validation data are
relevant to this procedure? [Reserved] Procedure 4. [Reserved]
Procedure 5. Quality Assurance Requirements for Vapor Phase Mercury
Continuous Emissions Monitoring Systems and Sorbent Trap Monitoring
Systems Used for Compliance Determination at Stationary Sources 1.0
Applicability and Principle
1.1 Applicability. The purpose of Procedure 5 is to establish
the minimum requirements for evaluating the effectiveness of
quality control (QC) and quality assurance (QA) procedures as well
as the quality of data produced by vapor phase mercury (Hg)
continuous emissions monitoring systems (CEMS) and sorbent trap
monitoring systems. Procedure 5 applies to Hg CEMS and sorbent trap
monitoring systems used for continuously determining compliance
with emission standards or operating permit limits as specified in
an applicable regulation or permit. Other QA/QC procedures may
apply to other auxiliary monitoring equipment that may be needed to
determine Hg emissions in the units of measure specified in an
applicable permit or regulation.
Procedure 5 covers the measurement of Hg emissions as defined in
Performance Specification 12A (PS 12A) and Performance
Specification 12B (PS 12B) in appendix B to this part, i.e.,
total vapor phase Hg representing the sum of the elemental (Hg°,
CAS Number 7439-97-6) and oxidized (Hg+2) forms of gaseous Hg.
Procedure 5 specifies the minimum requirements for controlling
and assessing the quality of Hg CEMS and sorbent trap monitoring
system data submitted to EPA or a delegated permitting authority.
You must meet these minimum requirements if you are responsible for
one or more Hg CEMS or sorbent trap monitoring systems used for
compliance monitoring. We encourage you to develop and implement a
more extensive QA program or to continue such programs where they
already exist.
You must comply with the basic requirements of Procedure 5
immediately following successful completion of the initial
performance test described in PS 12A or PS 12B in appendix B to
this part (as applicable).
1.2 Principle. The QA procedures consist of two distinct and
equally important functions. One function is the assessment of the
quality of the Hg CEMS or sorbent trap monitoring system data by
estimating accuracy. The other function is the control and
improvement of the quality of the CEMS or sorbent trap monitoring
system data by implementing QC policies and corrective actions.
These two functions form a control loop: When the assessment
function indicates that the data quality is inadequate, the quality
control effort must be increased until the data quality is
acceptable. In order to provide uniformity in the assessment and
reporting of data quality, this procedure explicitly specifies
assessment methods for calibration drift, system integrity, and
accuracy. Several of the procedures are based on those of PS 12A
and PS 12B in appendix B to this part. Because the control and
corrective action function encompasses a variety of policies,
specifications, standards, and corrective measures, this procedure
treats QC requirements in general terms to allow each source owner
or operator to develop a QC system that is most effective and
efficient for the circumstances.
2.0 Definitions
2.1 Mercury Continuous Emission Monitoring System (Hg
CEMS) means the equipment required for the determination of the
total vapor phase Hg concentration in the stack effluent. The Hg
CEMS consists of the following major subsystems:
2.1.1 Sample Interface means that portion of the CEMS
used for one or more of the following: sample acquisition, sample
transport, sample conditioning, and protection of the monitor from
the effects of the stack effluent.
2.1.2 Hg Analyzer means that portion of the Hg CEMS that
measures the total vapor phase Hg concentration and generates a
proportional output.
2.1.3 Data Recorder means that portion of the CEMS that
provides a permanent electronic record of the analyzer output. The
data recorder may provide automatic data reduction and CEMS control
capabilities.
2.2 Sorbent Trap Monitoring System means the total
equipment required for the collection of gaseous Hg samples using
paired three-partition sorbent traps as described in PS 12B in
appendix B to this part.
2.3 Span Value means the measurement range as specified
for the affected source category in the applicable regulation
and/or monitoring performance specification.
2.4 Zero, Mid-Level, and High Level Values means the
reference gas concentrations used for calibration drift assessments
and system integrity checks on a Hg CEMS, expressed as percentages
of the span value (see section 7.1 of PS 12A in appendix B
to this part).
2.5 Calibration Drift (CD) means the absolute value of
the difference between the CEMS output response and either the
upscale Hg reference gas or the zero-level Hg reference gas,
expressed as a percentage of the span value, when the entire CEMS,
including the sampling interface, is challenged after a stated
period of operation during which no unscheduled maintenance,
repair, or adjustment took place.
2.6 System Integrity (SI) Check means a test procedure
assessing transport and measurement of oxidized Hg by a Hg CEMS. In
particular, system integrity is expressed as the absolute value of
the difference between the CEMS output response and the reference
value of either a mid- or high-level mercuric chloride (HgCl2)
reference gas, as a percentage of span, when the entire CEMS,
including the sampling interface, is challenged.
2.7 Relative Accuracy (RA) means the absolute mean
difference between the pollutant concentrations determined by a
continuous monitoring system (e.g., Hg CEMS or sorbent trap
monitoring system) and the values determined by a reference method
(RM) plus the 2.5 percent error confidence coefficient of a series
of tests divided by the mean of the RM tests. Alternatively, for
sources with an average RM concentration less than 5.0 micrograms
per standard cubic meter (µg/scm), the RA may be expressed as the
absolute value of the difference between the mean CEMS and RM
values.
2.8 Relative Accuracy Test Audit (RATA) means an audit
test procedure consisting of at least nine runs, in which the
accuracy of the total vapor phase Hg concentrations measured by a
CEMS or sorbent trap monitoring system is evaluated by comparison
against concurrent measurements made with a reference test
method.
2.9 Quarterly Gas Audit (QGA) means an audit procedure in
which the accuracy of the total vapor phase Hg concentrations
measured by a CEMS is evaluated by challenging the CEMS with a zero
and two upscale reference gases.
3.0 QC Requirements
3.1 Each source owner or operator must develop and implement a
QC program. At a minimum, each QC program must include written
procedures which should describe in detail, complete, step-by-step
procedures and operations for each of the following activities (as
applicable):
(a) Calibration drift (CD) checks of Hg CEMS.
(b) CD determination and adjustment of Hg CEMS.
(c) Weekly system integrity check procedures for Hg CEMS.
(d) Routine operation, maintenance, and QA/QC procedures for
sorbent trap monitoring systems.
(e) Routine and preventive maintenance procedures for Hg CEMS
(including spare parts inventory).
(f) Data recording, calculations, and reporting.
(g) Accuracy audit procedures for Hg CEMS and sorbent trap
monitoring systems including sampling and analysis methods.
(h) Program of corrective action for malfunctioning Hg CEMS and
sorbent trap monitoring systems.
These written procedures must be kept on record and available
for inspection by the responsible enforcement agency. Also, as
noted in section 5.2.4, below, whenever excessive inaccuracies of a
Hg CEMS occur for two consecutive quarters, the source owner or
operator must revise the current written procedures or modify or
replace the CEMS or sorbent trap monitoring system to correct the
deficiency causing the excessive inaccuracies.
4.0 Calibration Drift (CD) Assessment
4.1 CD Requirement. As described in 40 CFR 60.13(d) and 63.8(c),
source owners and operators of Hg CEMS must check, record, and
quantify the CD at two concentration values at least once daily
(approximately 24 hours) in accordance with the method prescribed
by the manufacturer. The Hg CEMS calibration must, as minimum, be
adjusted whenever the daily zero (or low-level) CD or the daily
high-level CD exceeds two times the limits of the applicable PS in
appendix B of this part.
4.2 Recording Requirement for Automatic CD Adjusting CEMS. CEMS
that automatically adjust the data to the corrected calibration
values (e.g., microprocessor control) must either be programmed to
record the unadjusted concentration measured in the CD prior to
resetting the calibration, if performed, or to record the amount of
adjustment.
4.3 Criteria for Excessive CD. If either the zero (or low-level)
or high-level CD result exceeds twice the applicable drift
specification in section 13.2 of PS 12A in appendix B to this part
for five, consecutive, daily periods, the CEMS is out-of-control.
If either the zero (or low-level) or high-level CD result exceeds
four times the applicable drift specification in PS 12A during any
CD check, the CEMS is out-of-control. If the CEMS is
out-of-control, take necessary corrective action. Following
corrective action, repeat the CD checks.
4.3.1 Out-Of-Control Period Definition. The beginning of the
out-of-control period is the time corresponding to the completion
of the fifth, consecutive, daily CD check with a CD in excess of
two times the allowable limit, or the time corresponding to the
completion of the daily CD check preceding the daily CD check that
results in a CD in excess of four times the allowable limit. The
end of the out-of-control period is the time corresponding to the
completion of the CD check following corrective action that results
in the CD's at both the zero (or low-level) and high-level
measurement points being within the corresponding allowable CD
limit (i.e., either two times or four times the allowable
limit in the applicable PS in appendix B).
4.3.2 CEMS Data Status During Out-of-Control Period. During the
period the CEMS is out-of-control, the CEMS data may not be used
either to determine compliance with an emission limit or to meet a
minimum data availability requirement specified in an applicable
regulation or permit.
5.0 Data Accuracy Assessment
5.1 Hg CEMS Audit Requirements. For each Hg CEMS, an accuracy
audit must be performed at least once each calendar quarter.
Successive quarterly audits must, to the extent practicable, be
performed no less than 2 months apart. The audits must be conducted
as follows:
5.1.1 Relative Accuracy Test Audit (RATA). A RATA of the Hg CEMS
must be conducted at least once every four calendar quarters,
except as otherwise noted in section 5.1.4 of this appendix.
Perform the RATA as described in section 8.5 of PS 12A in appendix
B to this part. Calculate the results according to section 12.4 of
PS 12A.
5.1.2 Quarterly Gas Audit. A quarterly gas audit (QGA) may be
conducted in three of four calendar quarters, but in no more than
three quarters in succession. To perform a QGA, challenge the CEMS
with a zero-level and two upscale level audit gases of known
concentrations, first of elemental Hg and then of oxidized Hg,
within the following ranges:
Audit point
Audit range
1
20 to 30% of span value.
2
50 to 60% of span value.
Sequentially inject each of the three audit gases (zero and two
upscale), three times each for a total of nine injections. Inject
the gases in such a manner that the entire CEMS is challenged. Do
not inject the same gas concentration twice in succession.
Use elemental Hg and oxidized Hg (mercuric chloride, HgCl2)
audit gases that are National Institute of Standards and Technology
(NIST)-certified or NIST-traceable following an EPA Traceability
Protocol. If audit gas cylinders are used, do not dilute gas when
challenging the Hg CEMS. For each reference gas concentration,
determine the average of the three CEMS responses and subtract the
average response from the reference gas value. Calculate the
measurement error at each gas level using Equation 12A-1 in section
8.2 of PS 12A.
5.1.3 Relative Accuracy Audit (RAA). As an alternative to the
QGA, a RAA may be conducted in three of four calendar quarters, but
in no more than three quarters in succession. To conduct a RAA,
follow the RATA test procedures in section 8.5 of PS 12A in
appendix B to this part, except that only three test runs are
required.
5.1.4 Alternative Quarterly Audits. Alternative quarterly audit
procedures may be used as approved by the Administrator for three
of four calendar quarters. One RATA is required at least every four
calendar quarters, except in the case where the affected facility
is off-line (does not operate) in the fourth calendar quarter since
the quarter of the previous RATA. In that case, the RATA must be
performed in the quarter in which the unit recommences operation.
Also, quarterly gas audits (or RAAs, if applicable) are not
required for calendar quarters in which the affected facility does
not operate.
5.2 Sorbent Trap Monitoring System Audit Requirements. For each
sorbent trap monitoring system, a RATA must be conducted at least
once every four calendar quarters, except as otherwise noted in
section 5.1.4 of this appendix. Perform the RATA as described in
section 8.3 of PS 12B in appendix B to this part. Calculate the
results according to section 12.4 of PS 12A.
5.3 Excessive Audit Inaccuracy. If the results of a RATA, QGA,
or RAA exceed the applicable criteria in section 5.3.3, the Hg CEMS
or sorbent trap monitoring system is out-of-control. If the Hg CEMS
or sorbent trap monitoring system is out-of-control, take necessary
corrective action to eliminate the problem. Following corrective
action, the source owner or operator must audit the CEMS or sorbent
trap monitoring system using the same type of test that failed to
meet the accuracy criterion. For instance, a RATA must always be
performed following an out-of-control period resulting from a
failed RATA. Whenever audit results show the Hg CEMS or sorbent
trap monitoring system to be out-of-control, the owner or operator
must report both the results of the failed test and the results of
the retest following corrective action showing the CEMS to be
operating within specifications.
5.3.1 Out-Of-Control Period Definition. The beginning of the
out-of-control period is the hour immediately following the
completion of a RATA, RAA, QGA or system integrity check that fails
to meet the applicable performance criteria in section 5.3.3,
below. The end of the out-of-control period is the time
corresponding to the completion of a subsequent successful test of
the same type.
5.3.2 Monitoring Data Status During Out-Of-Control Period.
During the period the monitor is out-of-control, the monitoring
data may not be used to determine compliance with an applicable
emission limit or to meet a minimum data availability requirement
in an applicable regulation or permit.
5.3.3 Criteria for Excessive Audit Inaccuracy. Unless specified
otherwise in an applicable regulation or permit, the criteria for
excessive inaccuracy are:
(a) For the RATA, the allowable RA in the applicable PS in
appendix B (e.g., PS 12A or PS 12B).
(b) For the QGA, ±15 percent of the average audit value or ±0.5
µg/m 3, whichever is greater.
(c) For the RAA, ±20 percent of the three run average or ±10
percent of the applicable standard, whichever is greater.
5.3.4 Criteria for Acceptable QC Procedures. Repeated excessive
inaccuracies (i.e., out-of-control conditions resulting from
the quarterly audits) indicates the QC procedures are inadequate or
that the CEMS or sorbent trap monitoring system is incapable of
providing quality data. Therefore, whenever excessive inaccuracies
occur for two consecutive quarters, the source owner or operator
must revise the QC procedures (see section 3) or modify,
repair, or replace the CEMS or sorbent trap monitoring system.
6.0 Reporting Requirements
6.1 Data Assessment Report. At the reporting interval specified
in the applicable regulation or permit, report for each Hg CEMS
and/or sorbent trap monitoring system the accuracy assessment
results from section 5, above. For Hg CEMS, also report the CD
assessment results from section 4, above. Report this information
as a Data Assessment Report (DAR), and include the appropriate
DAR(s) with the emissions report required under the applicable
regulation or permit.
6.2 Contents of the DAR. At a minimum, the DAR must contain the
following information:
6.2.1 Facility name and address including identification of
source owner/operator.
6.2.2 Identification and location of each Hg CEMS and/or sorbent
trap monitoring system.
6.2.3 Manufacturer, model, and serial number of each Hg CEMS
and/or sorbent trap monitoring system.
6.2.4 CD Assessment for each Hg CEMS, including the
identification of out-of-control periods.
6.2.5 System integrity check data for each Hg CEMS.
6.2.6 Accuracy assessment for each Hg CEMS and/or sorbent trap
monitoring system, including the identification of out-of-control
periods. The results of all required RATAs, QGAs, RAAs, and audits
of auxiliary equipment must be reported. If an accuracy audit shows
a CEMS or sorbent trap monitoring system to be out-of-control,
report both the audit results that caused the out-of-control period
and the results of the retest following corrective action, showing
the monitoring system to be operating within specifications.
6.2.7 Summary of all corrective actions taken when the Hg CEMS
and/or sorbent trap monitoring system was determined to be
out-of-control.
6.3 Data Retention. As required in 40 CFR 60.7(d) and 63.10(b),
all measurements from CEMS and sorbent trap monitoring systems,
including the quality assurance data required by this procedure,
must be retained by the source owner for at least 5 years.
7.0 Bibliography
7.1 Calculation and Interpretation of Accuracy for Continuous
Emission Monitoring Systems (CEMS). section 3.0.7 of the Quality
Assurance Handbook for Air Pollution Measurement Systems, Volume
III, Stationary Source Specific Methods. EPA-600/4-77-027b. August
1977. U.S. Environmental Protection Agency. Office of Research and
Development Publications, 26 West St. Clair Street, Cincinnati, OH
45268.
Procedure 6. Quality Assurance Requirements for Gaseous Hydrogen
Chloride (HCl) Continuous Emission Monitoring Systems Used for
Compliance Determination at Stationary Sources 1.0 Applicability
and Principle
1.1 Applicability. Procedure 6 is used to evaluate the
effectiveness of quality control (QC) and quality assurance (QA)
procedures and evaluate the quality of data produced by any
hydrogen chloride (HCl) gas, CAS: 7647-01-0, continuous emission
monitoring system (CEMS) that is used for determining compliance
with emission standards for HCl on a continuous basis as specified
in an applicable permit or regulation.
1.1.1 This procedure specifies the minimum QA requirements
necessary for the control and assessment of the quality of CEMS
data submitted to the Environmental Protection Agency (EPA) or a
delegated authority. If you are responsible for one or more CEMS
used for HCl compliance monitoring you must meet these minimum
requirements and you are encouraged to develop and implement a more
extensive QA program or to continue such programs where they
already exist.
1.1.2 Data collected as a result of QA and QC measures required
in this procedure are to be submitted to the EPA or the delegated
authority in accordance with the applicable regulation or permit.
These data are to be used by both the delegated authority and you,
as the CEMS operator, in assessing the effectiveness of the CEMS QC
and QA procedures in the maintenance of acceptable CEMS operation
and valid emission data.
1.2 Principle
1.2.1 The QA procedures consist of two distinct and equally
important functions. One function is the assessment of the quality
of the CEMS data by estimating accuracy. The other function is the
control and improvement of the quality of the CEMS data by
implementing QC policies and corrective actions. These two
functions form an iterative control loop. When the assessment
function indicates that the data quality is inadequate, the control
effort must be increased until the data quality is acceptable. In
order to provide uniformity in the assessment and reporting of data
quality, this procedure specifies the assessment procedures to
evaluate response drift and accuracy. The procedures specified are
based on Performance Specification 18 (PS-18) in appendix B to this
part.
(Note: Because the control and corrective action function
encompasses a variety of policies, specifications, standards and
corrective measures, this procedure treats QC requirements in
general terms to allow you, as source owner or operator to develop
the most effective and efficient QC system for your
circumstances.)
2.0 Definitions
See PS-18 of this subpart for the primary definitions used in
this Procedure.
3.0 QC Requirements
3.1 You, as a source owner or operator, must develop and
implement a QC program. At a minimum, each QC program must include
written procedures and/or manufacturer's information which should
describe in detail, complete, step-by-step procedures and
operations for each of the following activities:
(a) Calibration Drift (CD) checks of CEMS;
(b) CD determination and adjustment of CEMS;
(c) Integrated Path (IP) CEMS temperature and pressure sensor
accuracy checks;
(d) IP CEMS beam intensity checks;
(e) Routine and preventative maintenance of CEMS (including
spare parts inventory);
(f) Data recording, calculations, and reporting;
(g) Accuracy audit procedures for CEMS including reference
method(s); and
(h) Program of corrective action for malfunctioning CEMS.
3.2 These written procedures must be kept on site and available
for inspection by the delegated authority. As described in section
5.4, whenever excessive inaccuracies occur for two consecutive
quarters, you must revise the current written procedures, or modify
or replace the CEMS to correct the deficiency causing the excessive
inaccuracies.
4.0 Daily Data Quality Requirements and Measurement Standardization
Procedures
4.1 CD Assessment. An upscale gas, used to meet a requirement in
this section must be either a NIST-traceable reference gas or a gas
certified by the gas vendor to ±5.0 percent accuracy.
4.1.1 CD Requirement. Consistent with 40 CFR 60.13(d) and
63.8(c), you, as source owners or operators of CEMS must check,
record, and quantify the CD at two levels, using a zero gas and
mid-level gas at least once daily (approximately every 24 hours).
Perform the CD check in accordance with the procedure in applicable
performance specification (e.g., section 11.8 of PS-18 in
appendix B of this part). The daily zero- and mid-level CD must not
exceed two times the drift limits specified in the applicable
performance specification (e.g., section 13.2 of PS-18 in
appendix B to this part.)
4.1.2 Recording Requirement for CD Corrective action. Corrective
actions taken to bring a CEMS back in control after exceeding a CD
limit must be recorded and reported with the associated CEMS data.
Reporting corrective action must include the unadjusted
concentration measured prior to resetting the calibration and the
adjusted value after resetting the calibration to bring the CEMS
back into control.
4.1.3 Dynamic Spiking Option for Mid-level CD. For extractive
CEMS, you have the option to conduct a daily dynamic spiking
procedure found in section 11.8.8 of PS-18 of appendix B of this
part in lieu of the daily mid-level CD check. If this option is
selected, the daily zero CD check is still required.
4.1.4 Out of Control Criteria for Excessive CD. As specified in
§ 63.8(c)(7)(i)(A), a CEMS is out of control if the zero or
mid-level CD exceeds two times the applicable CD specification in
the applicable PS or in the relevant standard. When a CEMS is out
of control, you as owner or operator of the affected source must
take the necessary corrective actions and repeat the tests that
caused the system to go out of control (in this case, the failed CD
check) until the applicable performance requirements are met.
4.1.5 Additional Quality Assurance for Data above Span. This
procedure must be used when required by an applicable regulation
and may be used when significant data above span are being
collected. Furthermore, the terms of this procedure do not apply to
the extent that alternate terms are otherwise specified in an
applicable rule or permit.
4.1.5.1 Any time the average measured concentration of HCl
exceeds 150 percent of the span value for two consecutive one-hour
averages, conduct the following 'above span' CEMS response
check.
4.1.5.1.1 Within a period of 24 hours (before or after) of the
'above span' period, introduce a higher, 'above span' HCl reference
gas standard to the CEMS. Use 'above span' reference gas that meets
the requirements of section 7.0 of PS-18 and target a concentration
level between 75 and 125 percent of the highest hourly
concentration measured during the period of measurements above
span.
4.1.5.1.2 Introduce the reference gas at the probe for
extractive CEMS or for IP-CEMS as an equivalent path length
corrected concentration in the instrument calibration cell.
4.1.5.1.3 At no time may the 'above span' concentration exceed
the analyzer full-scale range.
4.1.5.2 Record and report the results of this procedure as you
would for a daily calibration. The 'above span' response check is
successful if the value measured by the CEMS is within 20 percent
of the certified value of the reference gas.
4.1.5.3 If the 'above span' response check is conducted during
the period when measured emissions are above span and there is a
failure to collect at least one data point in an hour due to the
response check duration, then determine the emissions average for
that missed hour as the average of hourly averages for the hour
preceding the missed hour and the hour following the missed
hour.
4.1.5.4 In the event that the 'above span' response check is not
successful (i.e., the CEMS measured value is not within 20
percent of the certified value of the reference gas), then you must
normalize the one-hour average stack gas values measured above the
span during the 24-hour period preceding or following the 'above
span' response check for reporting based on the CEMS response to
the reference gas as shown in Eq. 6-1:
4.2 Beam
Intensity Requirement for HCl IP-CEMS.
4.2.1 Beam Intensity Measurement. If you use a HCl IP-CEMS, you
must quantify and record the beam intensity of the IP-CEMS in
appropriate units at least once daily (approximately 24 hours
apart) according to manufacturer's specifications and
procedures.
4.2.2 Out of Control Criteria for Excessive Beam Intensity Loss.
If the beam intensity falls below the level established for the
operation range determined following the procedures in section 11.2
of PS-18 of this part, then your CEMS is out-of-control. This
quality check is independent of whether the CEMS daily CD is
acceptable. If your CEMS is out-of-control, take necessary
corrective action. You have the option to repeat the beam intensity
test procedures in section 11.2 of PS-18 to expand the acceptable
range of acceptable beam intensity. Following corrective action,
repeat the beam intensity check.
4.3 Out Of Control Period Duration for Daily Assessments. The
beginning of the out-of-control period is the hour in which the
owner or operator conducts a daily performance check (e.g.,
calibration drift or beam intensity check) that indicates an
exceedance of the performance requirements established under this
procedure. The end of the out-of-control period is the completion
of daily assessment of the same type following corrective actions,
which shows that the applicable performance requirements have been
met.
4.4 CEMS Data Status During Out-of-Control Period. During the
period the CEMS is out-of-control, the CEMS data may not be used in
calculating compliance with an emissions limit nor be counted
towards meeting minimum data availability as required and described
in the applicable regulation or permit.
5.0 Data Accuracy Assessment
You must audit your CEMS for the accuracy of HCl measurement on
a regular basis at the frequency described in this section, unless
otherwise specified in an applicable regulation or permit.
Quarterly audits are performed at least once each calendar quarter.
Successive quarterly audits, to the extent practicable, shall occur
no closer than 2 months apart. Annual audits are performed at least
once every four consecutive calendar quarters.
5.1 Temperature and Pressure Accuracy Assessment for IP CEMS.
5.1.1 Stack or source gas temperature measurement audits for HCl
IP-CEMS must be conducted and recorded at least annually in
accordance with the procedure described in section 11.3 of PS-18 in
appendix B to this part. As an alternative, temperature measurement
devices may be replaced with certified instruments on an annual
basis. Units removed from service may be bench tested against an
NIST traceable sensor and reused during subsequent years. Any
measurement instrument or device that is used to conduct ongoing
verification of temperature measurement must have an accuracy that
is traceable to NIST.
5.1.2 Stack or source gas pressure measurement audits for HCl
IP-CEMS must be conducted and recorded at least annually in
accordance with the procedure described in section 11.4 of PS-18 in
appendix B of this part. As an alternative, pressure measurement
devices may be replaced with certified instruments on an annual
basis. Units removed from service may be bench tested against an
NIST traceable sensor and reused during subsequent years. Any
measurement instrument or device that is used to conduct ongoing
verification of pressure measurement must have an accuracy that is
traceable to NIST.
5.1.3 Out of Control Criteria for Excessive Parameter
Verification Inaccuracy. If the temperature or pressure
verification audit exceeds the criteria in sections 5.3.4.5 and
5.3.4.6, respectively, the CEMS is out-of-control. If the CEMS is
out-of-control, take necessary corrective action to eliminate the
problem. Following corrective action, you must repeat the failed
verification audit until the temperature or pressure measurement
device is operating within the applicable specifications, at which
point the out-of-control period ends.
5.2 Concentration Accuracy Auditing Requirements. Unless
otherwise specified in an applicable rule or permit, you must audit
the HCl measurement accuracy of each CEMS at least once each
calendar quarter, except in the case where the affected facility is
off-line (does not operate). In that case, the audit must be
performed as soon as is practicable in the quarter in which the
unit recommences operation. Successive quarterly audits must, to
the extent practicable, be performed no less than 2 months apart.
The accuracy audits shall be conducted as follows:
5.2.1 Relative Accuracy Test Audit. A RATA must be conducted at
least once every four calendar quarters, except as otherwise noted
in sections 5.2.5 or 5.5 of this procedure. Perform the RATA as
described in section 11.9 of PS-18 in appendix B to this part. If
the HCl concentration measured by the RM during a RATA (in ppmv) is
less than or equal to 20 percent of the concentration equivalent to
the applicable emission standard, you must perform a Cylinder Gas
Audit (CGA) or a Dynamic Spike Audit (DSA) for at least one
subsequent (one of the following three) quarterly accuracy
audits.
5.2.2 Quarterly Relative Accuracy Audit (RAA). A quarterly RAA
may be conducted as an option to conducting a RATA in three of four
calendar quarters, but in no more than three quarters in
succession. To conduct an RAA, follow the test procedures in
section 11.9 of PS-18 in appendix B to this part, except that only
three test runs are required. The difference between the mean of
the RM values and the mean of the CEMS responses relative to the
mean of the RM values (or alternatively the emission standard) is
used to assess the accuracy of the CEMS. Calculate the RAA results
as described in section 6.2. As an alternative to an RAA, a
cylinder gas audit or a dynamic spiking audit may be conducted.
5.2.3 Cylinder Gas Audit. A quarterly CGA may be conducted as an
option to conducting a RATA in three of four calendar quarters, but
in no more than three consecutive quarters. To perform a CGA,
challenge the CEMS with a zero-level and two upscale level audit
gases of known concentrations within the following ranges:
Audit point
Audit range
1 (Mid-Level)
50 to 60% of span value.
2
(High-Level)
80 to 100% of span value.
5.2.3.1 Inject each of the three audit gases (zero and two
upscale) three times each for a total of nine injections. Inject
the gases in such a manner that the entire CEMS is challenged. Do
not inject the same gas concentration twice in succession.
5.2.3.2 Use HCl audit gases that meet the requirements of
section 7 of PS-18 in appendix B to this part.
5.2.3.3 Calculate results as described in section 6.3.
5.2.4 Dynamic Spiking Audit. For extractive CEMS, a quarterly
DSA may be conducted as an option to conducting a RATA in three of
four calendar quarters, but in no more than three quarters in
succession.
5.2.4.1 To conduct a DSA, you must challenge the entire HCl CEMS
with a zero gas in accordance with the procedure in section 11.8 of
PS-18 in appendix B of this part. You must also conduct the DS
procedure as described in appendix A to PS-18 of appendix B to this
part. You must conduct three spike injections with each of two
upscale level audit gases. The upscale level gases must meet the
requirements of section 7 of PS-18 in appendix B to this part and
must be chosen to yield concentrations at the analyzer of 50 to 60
percent of span and 80 to 100 percent of span. Do not inject the
same gas concentration twice in succession.
5.2.4.2 Calculate results as described in section 6.4. To
determine CEMS accuracy, you must calculate the dynamic spiking
error (DSE) for each of the two upscale audit gases using Equation
A5 in appendix A to PS-18 and Equation 6-3 in section 6.4 of
Procedure 6 in appendix B to this part.
5.2.5 Other Alternative Quarterly Audits. Other alternative
audit procedures, as approved by the Administrator, may be used for
three of four calendar quarters.
5.3 Out of Control Criteria for Excessive Audit Inaccuracy. If
the results of the RATA, RAA, CGA, or DSA do not meet the
applicable performance criteria in section 5.3.4, the CEMS is
out-of-control. If the CEMS is out-of-control, take necessary
corrective action to eliminate the problem. Following corrective
action, the CEMS must pass a test of the same type that resulted in
the out-of-control period to determine if the CEMS is operating
within the specifications (e.g., a RATA must always follow
an out-of-control period resulting from a RATA).
5.3.1 If the audit results show the CEMS to be out-of-control,
you must report both the results of the audit showing the CEMS to
be out-of-control and the results of the audit following corrective
action showing the CEMS to be operating within specifications.
5.3.2 Out-Of-Control Period Duration for Excessive Audit
Inaccuracy. The beginning of the out-of-control period is the time
corresponding to the completion of the sampling for the failed
RATA, RAA, CGA or DSA. The end of the out-of-control period is the
time corresponding to the completion of the sampling of the
subsequent successful audit.
5.3.3 CEMS Data Status During Out-Of-Control Period. During the
period the CEMS is out-of-control, the CEMS data may not be used in
calculating emission compliance nor be counted towards meeting
minimum data availability as required and described in the
applicable regulation or permit.
5.3.4 Criteria for Excessive Quarterly and Yearly Audit
Inaccuracy. Unless specified otherwise in the applicable regulation
or permit, the criteria for excessive inaccuracy are:
5.3.4.1 For the RATA, the CEMS must meet the RA specifications
in section 13.4 of PS-18 in appendix B to this part.
5.3.4.2 For the CGA, the accuracy must not exceed 5.0 percent of
the span value at the zero gas and the mid- and high-level
reference gas concentrations.
5.3.4.3 For the RAA, the RA must not exceed 20.0 percent of the
RMavg as calculated using Equation 6-2 in section 6.2 of this
procedure whether calculated in units of HCl concentration or in
units of the emission standard. In cases where the RA is calculated
on a concentration (ppmv) basis, if the average HCl concentration
measured by the RM during the test is less than 75 percent of the
HCl concentration equivalent to the applicable standard, you may
substitute the equivalent emission standard value (in ppmvw) in the
denominator of Equation 6-2 in the place of RMavg and the result of
this alternative calculation of RA must not exceed 15.0
percent.
5.3.4.4 For DSA, the accuracy must not exceed 5.0 percent of the
span value at the zero gas and the mid- and high-level reference
gas concentrations or 20.0 percent of the applicable emission
standard, whichever is greater.
5.3.4.5 For the gas temperature measurement audit, the CEMS must
satisfy the requirements in section 13.7 in PS-18 of appendix B to
this part.
5.3.4.6 For the gas pressure measurement audit, the CEMS must
satisfy the requirements in section 13.8 in PS-18 of appendix B to
this part.
5.4 Criteria for Acceptable QC Procedures. Repeated excessive
inaccuracies (i.e., out-of-control conditions resulting from
the quarterly or yearly audits) indicate that the QC procedures are
inadequate or that the CEMS is incapable of providing quality data.
Therefore, whenever excessive inaccuracies occur for two
consecutive quarters, you must revise the QC procedures (see
section 3.0) or modify or replace the CEMS.
5.5 Criteria for Optional QA Test Frequency. If all the quality
criteria are met in sections 4 and 5 of this procedure, the CEMS is
in-control.
5.5.1 Unless otherwise specified in an applicable rule or
permit, if the CEMS is in-control and if your source emits ≤75
percent of the HCl emission limit for each averaging period as
specified in the relevant standard for eight consecutive quarters
that include a minimum of two RATAs, you may revise your auditing
procedures to use CGA, RAA or DSA each quarter for seven subsequent
quarters following a RATA.
5.5.2 You must perform at least one RATA that meets the
acceptance criteria every 2 years.
5.5.3 If you fail a RATA, RAA, CGA, or DSA, then the audit
schedule in section 5.2 must be followed until the audit results
meet the criteria in section 5.3.4 to start requalifying for the
optional QA test frequency in section 5.5.
6.0 Calculations for CEMS Data Accuracy
6.1 RATA RA Calculation. Follow Equations 9 through 14 in
section 12 of PS-18 in appendix B to this part to calculate the RA
for the RATA. The RATA must be calculated either in units of the
applicable emission standard or in concentration units (ppmv).
6.2 RAA Accuracy Calculation. Use Equation 6-2 to calculate the
accuracy for the RAA. The RA may be calculated in concentration
units (ppmv) or in the units of the applicable emission
standard.
Where: RA
= Accuracy of the CEMS (percent) MNavg = Average measured CEMS
response during the audit in units of applicable standard or
appropriate concentration. RMavg = Average reference method value
in units of applicable standard or appropriate concentration.
6.3 CGA Accuracy Calculation. For each gas concentration,
determine the average of the three CEMS responses and subtract the
average response from the audit gas value. For extractive CEMS,
calculate the ME at each gas level using Equation 3A in section
12.3 of PS-18 in appendix B to this part. For IP-CEMS, calculate
the ME at each gas level using Equation 6A in section 12.4.3 of
PS-18 in appendix B to this part.
6.4 DSA Accuracy Calculation. DSA accuracy is calculated as a
percent of span. To calculate the DSA accuracy for each upscale
spike concentration, first calculate the DSE using Equation A5 in
appendix A of PS-18 in appendix B to this part. Then use Equation
6-3 to calculate the average DSA accuracy for each upscale spike
concentration. To calculate DSA accuracy at the zero level, use
equation 3A in section 12.3 of PS-18 in appendix B to this
part.
7.0
Reporting Requirements
At the reporting interval specified in the applicable regulation
or permit, report for each CEMS the quarterly and annual accuracy
audit results from section 6 and the daily assessment results from
section 4. Unless otherwise specified in the applicable regulation
or permit, include all data sheets, calculations, CEMS data records
(i.e., charts, records of CEMS responses), reference gas
certifications and reference method results necessary to confirm
that the performance of the CEMS met the performance
specifications.
7.1 Unless otherwise specified in the applicable regulations or
permit, report the daily assessments (CD and beam intensity) and
accuracy audit information at the interval for emissions reporting
required under the applicable regulations or permits.
7.1.1 At a minimum, the daily assessments and accuracy audit
information reporting must contain the following information:
a. Company name and address.
b. Identification and location of monitors in the CEMS.
c. Manufacturer and model number of each monitor in the
CEMS.
d. Assessment of CEMS data accuracy and date of assessment as
determined by a RATA, RAA, CGA or DSA described in section 5
including:
i. The RA for the RATA;
ii. The accuracy for the CGA, RAA, or DSA;
iiii. Temperature and pressure sensor audit results for
IP-CEMS;
iv. The RM results, the reference gas certified values;
v. The CEMS responses;
vi. The calculation results as defined in section 6; and
vii. Results from the performance audit samples described in
section 5 and the applicable RMs.
e. Summary of all out-of-control periods including corrective
actions taken when CEMS was determined out-of-control, as described
in sections 4 and 5.
7.1.2 If the accuracy audit results show the CEMS to be
out-of-control, you must report both the audit results showing the
CEMS to be out-of-control and the results of the audit following
corrective action showing the CEMS to be operating within
specifications.
8.0 Bibliography
1. EPA Traceability Protocol for Assay and Certification of
Gaseous Calibration Standards, U.S. Environmental Protection Agency
office of Research and Development, EPA/600/R-12/531, May 2012.
2. Method 205, “Verification of Gas Dilution Systems for Field
Instrument Calibrations,” 40 CFR part 51, appendix M.
9.0 Tables, Diagrams, Flowcharts [Reserved] [52 FR 21008, June 4,
1987; 52 FR 27612, July 22, 1987, as amended at 56 FR 5527, Feb.
11, 1991; 69 FR 1816, Jan. 12, 2004; 72 FR 32768, June 13, 2007; 74
FR 12590, Mar. 25, 2009; 75 FR 55040, Sept. 9, 2010; 79 FR 11274,
Feb. 27, 2014; 79 FR 28441, May 16, 2014; 80 FR 38649, July 7,
2015; 81 FR 59824, Aug. 30, 2016; 82 FR 37824, Aug. 14, 2017; 82 FR
44108, Sept. 21, 2017; 83 FR 56725, Nov. 14, 2018; 85 FR 63418,
Oct. 7, 2020]
Appendix G to Part 60 - Provisions for an Alternative Method of Demonstrating Compliance With 40 CFR 60.43 for the Newton Power Station of Central Illinois Public Service Company
40:9.0.1.1.1.0.1.1.14 : Appendix G
Appendix G to Part 60 - Provisions for an Alternative Method of
Demonstrating Compliance With 40 CFR 60.43 for the Newton Power
Station of Central Illinois Public Service Company
1. Designation of Affected Facilities
1.1 The affected facilities to which this alternative compliance
method applies are the Unit 1 and 2 coal-fired steam generating
units located at the Central Illinois Public Service Company's
(CIPS) Newton Power Station in Jasper County, Illinois. Each of
these units is subject to the Standards of Performance for
Fossil-Fuel-Fired Steam Generators for Which Construction Commenced
After August 17, 1971 (subpart D).
2. Definitions
2.1 All definitions in subparts D and Da of part 60 apply to
this provision except that:
24-hour period means the period of time between 12:00
midnight and the following midnight.
Boiler operating day means a 24-hour period during which
any fossil is combusted in either the Unit 1 or Unit 2 steam
generating unit and during which the provisions of § 60.43(e) are
applicable.
CEMs means continuous emission monitoring system.
Coal bunker means a single or group of coal trailers,
hoppers, silos or other containers that:
(1) are physically attached to the affected facility; and
(2) provide coal to the coal pulverizers.
DAFGDS means the dual alkali flue gas desulfurization
system for the Newton Unit 1 steam generating unit.
3. Compliance Provisions
3.1 If the owner or operator of the affected facility elects to
comply with the 470 ng/J (1.1 lbs/MMBTU) of combined heat input
emission limit under § 60.43(e), he shall notify the Regional
Administrator, of the United States Environmental Protection Agency
(USEPA), Region 5 and the Director, of the Illinois Environmental
Protection Agency (IEPA) at least 30 days in advance of the date
such election is to take effect, stating the date such operation is
to commence. When the owner or operator elects to comply with this
limit after one or more periods of reverting to the 520 ng/J heat
input (1.2 lbs/MMBTU) limit of § 60.43(a)(2), as provided under
3.4, he shall notify the Regional Administrator of the USEPA,
Region 5 and the Director of the (IEPA) in writing at least ten
(10) days in advance of the date such election is to take
effect.
3.2 Compliance with the sulfur dioxide emission limit under §
60.43(e) is determined on a continuous basis by performance testing
using CEMs. Within 60 days after the initial operation of Units 1
and 2 subject to the combined emission limit in § 60.43(e), the
owner or operator shall conduct an initial performance test, as
required by § 60.8, to determine compliance with the combined
emission limit. This initial performance test is to be scheduled so
that the thirtieth boiler operating day of the 30 successive boiler
operating days is completed within 60 days after initial operation
subject to the 470 ng/J (1.1 lbs/MMBTU) combined emission limit.
Following the initial performance test, a separate performance test
is completed at the end of each boiler operating day Unit 1 and
Unit 2 are subject to § 60.43(e), and a new 30 day average emission
rate calculated.
3.2.1 Following the initial performance test, a new 30 day
average emission rate is calculated for each boiler operating day
the affected facility is subject to § 60.43(e). If the owner or
operator of the affected facility elects to comply with § 60.43(e)
after one or more periods of reverting to the 520 ng/J heat input
(1.2 lbs/MMBTU) limit under § 60.43(a)(2), as provided under 3.4,
the 30 day average emission rate under § 60.43(e) is calculated
using emissions data of the current boiler operating day and data
for the previous 29 boiler operating days when the affected
facility was subject to § 60.43(e). Periods of operation of the
affected facility under § 60.43(a)(2) are not considered boiler
operating days. Emissions data collected during operation under §
60.43(a)(2) are not considered relative to 4.6 and emissions data
are not included in calculations of emission under § 60.43(e).
3.2.2 When the affected facility is operated under the
provisions of § 60.43(e), the Unit 1 DAFGDS bypass damper must be
fully closed. The DAFGDS bypass may be opened only during periods
of DAFGDS startup, shutdown, malfunction or testing as described
under sections 3.5.1, 3.5.2, 3.5.3, 3.5.4, and 4.8.2.
3.3 Compliance with the sulfur dioxide emission limit set forth
in § 60.43(e) is based on the average combined hourly emission rate
from Units 1 and 2 for 30 successive boiler operating days
determined as follows:
where: n
= the number of available hourly combined emission rate values in
the 30 successive boiler operating day period where Unit 1 and Unit
2 are subject to § 60.43(e). E30 = average emission rate for 30
successive boiler operating days where Unit 1 and Unit 2 are
subject to § 60.43(e). EC = the hourly combined emission rate from
Units 1 and 2, in ng/J or lbs/MMBTU.
3.3.1 The average hourly combined emission rate for Units 1 and
2for each hour of operation of either Unit 1 or 2, or both, is
determined as follows:
EC=[(E1) + (E2)]/[H1 + H2] where: EC = the hourly combined SO2
emission rate, lbs/MMBTU, from Units 1 and 2 when Units 1 and 2 are
subject to § 60.43(e). E1 = the hourly SO2 mass emission, lb/hr,
from Unit 1 as determined from CEMs data using the calculation
procedures in section 4 of this appendix. E2 = the hourly SO2 mass
emission, lb/hr, from Unit 2 as determined from CEMs data using the
calculation procedures in section 4 of this appendix. H1 = the
hourly heat input, MMBTU/HR to Unit 1 as determined in section 4 of
this appendix. H2 = the hourly heat input, MMBTU/HR, to Unit 2 as
determined by section 4 of this appendix.
3.3.2 If data for any of the four hourly parameters (E1, E2,
H1and H2, under 3.3.1 are unavailable during an hourly period, the
combined emission rate (EC) is not calculated and the period is
counted as missing data under 4.6.1., except as provided under 3.5.
and 4.4.2.
3.4 After the date of initial operation subject to the combined
emission limit, Units 1 and 2 shall remain subject to the combined
emission limit and the owner or operator shall remain subject to
the requirements of this Appendix until the initial performance
test as required by 3.2 is completed and the owner or operator of
the affected facility elects and provides notice to revert on a
certain date to the 520 ng/J heat input (1.2 lbs/MMBTU) limit of §
60.43(a)(2) applicable separately at each unit. The Regional
Administrator of the USEPA, Region 5 and the Director, of the IEPA
shall be given written notification from CIPS as soon as possible
of CIPs' decision to revert to the 520 ng/J heat input (1.2
lbs/MMBTU) limit of § 60.43(a)(2) separately at each unit, but no
later than 10 days in advance of the date such election is to take
effect.
3.5 Emission monitoring data for Unit 1 may be excluded from
calculations of the 30 day rolling average only during the
following times:
3.5.1 Periods of DAFGDS startup.
3.5.2 Periods of DAFGDS shutdown.
3.5.3 Periods of DAFGDS malfunction during system emergencies as
defined in § 60.41a.
3.5.4 The first 250 hours per calendar year of DAFGDS
malfunctions of Unit 1 DAFGDS provided that efforts are made to
minimize emissions from Unit 1 in accordance with § 60.11(d), and
if, after 16 hours but not more than 24 hours of DAFGDS
malfunction, the owner or operator of the affected facility begins
(following the customary loading procedures) loading into the Unit
1 coal bunker, coal with a potential SO2 emission rate equal to or
less than the emission rate of Unit 2 recorded at the beginning of
the DAFGDS malfunction. Malfunction periods under 3.5.3 are not
counted toward the 250 hour/yr limit under this section.
3.5.4.1 The malfunction exemption in 3.5.4 is limited to the
first 250 hours per calendar year of DAFGDS malfunction.
3.5.4.2 For malfunctions of the DAFGDS after the 250 hours per
calendar year limit (cumulative), other than those defined in
3.5.3, the owner or operator of the affected facility shall combust
lower sulfur coal or use any other method to comply with the 470
ng/J (1.1 lbs/MMBTU) combined emission limit.
3.5.4.3 During the first 250 hours of DAFGDS malfunction per
year or during periods of DAFGDS startup, or DAFGDS shutdown, CEMs
emissions data from Unit 2 shall continue to be included in the
daily calculation of the combined 30 day rolling average emission
rate; that is, the load on Unit 1 is assumed to be zero (H1 and E1
= O; EC = E2/H2).
3.5.5-3.5.7 [Reserved]
3.6 The provision for excluding CEMs data from Unit 1 during the
first 250 hours of DAFGDS malfunctions from combined hourly
emissions calculations supersedes the provisions of § 60.11(d).
However, the general purpose contained in § 60.11(d) (i.e.,
following good control practices to minimize air pollution emission
during malfunctions) has not been superseded.
4. Continuous Emission Monitoring
4.1 The CEMs required under section 3.2 are operated and data
are recorded for all periods of operation of the affected facility
including periods of the DAFGDS startup, shutdown and malfunction
except for CEMs breakdowns, repairs, calibration checks, and zero
and span adjustment. All provisions of § 60.45 apply except as
follows:
4.2 The owner or operator shall install, calibrate, maintain,
and operate CEMs and monitoring devices for measuring the
following:
4.2.1 For Unit 1:
4.2.1.1 Sulfur dioxide, oxygen or carbon dioxide, and volumetric
flow rate for the Unit 1 DAFGDS stack.
4.2.1.2 Sulfur dioxide, oxygen or carbon dioxide, and volumetric
flow rate for the Unit 1 DAFGDS bypass stack.
4.2.1.3 Moisture content of the flue gas must be determined
continuously for the Unit 1 DAFGDS stack and the Unit 1 DAFGDS
bypass stack, if the sulfur dioxide concentration in each stack is
measured on a dry basis.
4.2.2 For Unit 2, sulfur dioxide, oxygen or carbon dioxide, and
volumetric flow rate.
4.2.2.1 Moisture content of the flue gas must be determined
continuously for the Unit 2 stack, if the sulfur dioxide
concentration in the stack is measured on a dry basis.
4.2.3 For Units 1 and 2, the hourly heat input, the hourly steam
production rate, or the hourly gross electrical power output from
each unit.
4.3 For the Unit 1 bypass stack and the Unit 2 stack, the span
value of the sulfur dioxide analyzer shall be equivalent to 200
percent of the maximum estimated hourly potential sulfur dioxide
emissions of the fuel fired in parts per million sulfur dioxide.
For the Unit 1 DAFGDS stack, the span value of the sulfur dioxide
analyzer shall be equivalent to 100 percent of the maximum
estimated hourly potential emissions of the fuel fired in parts per
million sulfur dioxide. The span value for volumetric flow monitors
shall be equivalent to 125 percent of the maximum estimated hourly
flow in standard cubic meters/minute (standard cubic feet per
minute). The span value of the continuous moisture monitors, if
required by 4.2.1.3 and 4.2.2.1, shall be equivalent to 100 percent
by volume. The span value of the oxygen or carbon dioxide analyzers
shall be equivalent to 25 percent by volume.
4.3.1-4.3.2 [Reserved]
4.4 The monitoring devices required in 4.2 shall be installed,
calibrated, and maintained as follows:
4.4.1 Each volumetric flow rate monitoring device specified in
4.2 shall be installed at approximately the same location as the
sulfur dioxide emission monitoring sample location.
4.4.2 Hourly steam production rate and hourly electrical power
output monitoring devices for Unit 1 and Unit 2 shall be calibrated
and maintained according to manufacturer's specifications. The data
from either of these devices may be used in the calculation of the
combined emission rate in section 3.3.1, only when the hourly heat
input for Unit 1 (H1) or the hourly heat input for Unit 2 (H2)
cannot be determined from CEM data, and the hourly heat input to
steam production or hourly heat input to electrical power output
efficiency over a given segment of each boiler or generator
operating range, respectively, varies by less than 5 percent within
the specified operating range, or the efficiencies of the
boiler/generator units differ by less than 5 percent. The hourly
heat input for Unit 1 (H1) or the hourly heat input for Unit 2 (H2)
in section 3.3.1 may also be calculated based on the fuel firing
rates and fuel analysis.
4.4.3-4.4.5 [Reserved]
4.5 The hourly mass emissions from Unit 1 (E1) and Unit 2 (E2)
and the hourly heat inputs from Unit 1 (H1) and Unit 2 (H2) used to
determine the hourly combined emission rate for Units 1 and 2 (EC)
in section 3.3.1 are calculated using CEM data for each respective
stack as follows:
4.5.1 The hourly SO2 mass emission from each respective stack is
determined as follows:
E = (C) (F) (D) (K) Where: E = SO2 mass emission from the
respective stack in lb per hour C = SO2 concentration from the
respective stack ppm F = flue gas flow rate from the respective
stack in scfm D = density of SO2 in lb per standard cubic feet K =
time conversion, 60 mins./hr
4.5.2 The hourly heat input from each respective stack is
determined as follows:
H=[(F) (C) (K)/(Fc) where: H = heat input from the respective stack
in MMBTU per hour C = CO2 or O2 concentration from the respective
stack as a decimal F = flue gas flow rate from the respective stack
in scfm K = time conversion, 60 mins./hr Fc = fuel constant for the
appropriate diluent in scf/MMBTU as per §§ 60.45(f) (4) and (5)
4.5.3 The hourly SO2 mass emission for Unit 1 in pounds per hour
(E1) is calculated as follows, when leakage or diversion of any
DAFGDS inlet gas to the bypass stack occurs:
E1 = (EF) + (EB) Where: EF = Hourly SO2 mass emission measured in
DAFGDS stack, lb/hr, using the calculation in section 4.5.1. EB =
Hourly SO2 mass emission measured in bypass stack, lb/hr, using the
calculation in section 4.5.1. Other than during conditions under
3.5.1, 3.5.2, 3.5.3, 3.5.4, or 4.8.2, the DAFGDS bypass damper must
be fully closed and any leakage will be indicated by the bypass
stack volumetric flow and SO2 measurements, and when no leakage
through the bypass damper is indicated: E1 = EF
4.5.4 The hourly heat input for Unit 1 in MMBTU per hour (H1) is
calculated as follows, when leakage or diversion of any DAFGDS
inlet gas to the bypass stack occurs:
H1 = (HF) + (HB) where: HF = Hourly heat input as determined from
the DAFGDS stack CEMs, in MMBTU per hour, using the calculation in
section 4.5.2 HB = Hourly heat input as determined from the DAFGDS
bypass stack CEMs, in MMBTU per hour, using the calculation in
section 4.5.2
4.6 For the CEMs required for Unit 1 and Unit 2, the owner or
operator of the affected facility shall maintain and operate the
CEMs and obtain combined emission data values (EC) for at least 75
percent of the boiler operting hours per day for at least 26 out of
each 30 successive boiler operating days.
4.6.1 When hourly SO2 emission data are not obtained by the CEMs
because of CEMs breakdowns, repairs, calibration checks and zero
and span adjustment, hourly emission data required by 4.6 are
obtained by using Methods 6 or 6C and 3 or 3A, 6A, or 8 and 3, or
by other alternative methods approved by the Regional Administrator
of the USEPA, Region 5 and the Director, of the IEPA. Failure to
obtain the minimum data requirements of 4.6 by CEMs, or by CEMs
supplemented with alternative methods of this section, is a
violation of performance testing requirements.
4.6.2 Independent of complying with the minimum data
requirements of 4.6, all valid emissions data collected are used to
calculate combined hourly emission rates (EC) and 30-day rolling
average emission rates (E30) are calculated and used to judge
compliance with 60.43(e).
4.7 For each continuous emission monitoring system, a quality
control plan shall be prepared by CIPS and submitted to the
Regional Administrator of the USEPA, Region 5 and the Director, of
the IEPA. The plan is to be submitted to the Regional Administrator
of the USEPA, Region 5 and the Director, of the IEPA 45 days before
initiation of the initial performance test. At a minimum, the plan
shall contain the following quality control elements:
4.7.1 Calibration of continuous emission monitoring systems
(CEMs) and volumetric flow measurement devices.
4.7.2 Calibration drift determination and adjustment of CEMs and
volumetric flow measurement devices.
4.7.4 Preventive maintenance of CEMs and volumetric flow
measurement devices (including spare parts inventory).
4.7.5 Data recording and reporting.
4.7.6 Program of corrective action for malfunctioning CEMs and
volumetric flow measurement devices.
4.7.7 Criteria for determining when the CEMs and volumetric flow
measurement devices are not producing valid data.
4.7.8 Calibration and periodic checks of monitoring devices
identified in 4.4.2.
4.8 For the purpose of conducting the continuous emission
monitoring system performance specification tests as required by §
60.13 and appendix B, the following conditions apply:
4.8.1 The calibration drift specification of Performance
Specification 2, appendix B shall be determined separately for each
of the Unit 1 SO2 CEMs and the Unit 2 SO2 CEMs. The calibration
drift specification of Performance Specification 3, appendix B
shall be determined separately for each of the Unit 1 diluent CEMs
and Unit 2 diluent CEMs.
4.8.2 The relative accuracy of the combined SO2 emission rate
for Unit 1 and Unit 2, as calculated from CEMs and volumetric flow
data using the procedures in 3.3.1, 4.5.1, 4.5.2 and 4.5.3 shall be
no greater than 20 percent of the mean value of the combined
emission rate, as determined from testing conducted simultaneously
on the DAFGDS stack, the DAFGDS bypass stack and the Unit 2 stack
using reference methods 2, 3, or 3A and 6 or 6C, or shall be no
greater than 10 percent of the emission limit in § 60.43(e),
whichever criteria is less stringent. The relative accuracy shall
be computed from at least nine comparisons of the combined emission
rate values using the procedures in section 7 and the equations in
section 8, Performance Specification 2, appendix B. Throughout, but
only during, the relative accuracy test period the DAFGDS bypass
damper shall be partially opened such that there is a detectable
flow.
4.8.3-4.8.3.4 [Reserved]
4.9 The total monitoring system required by 4.2 shall be subject
only to an annual relative accuracy test audit (RATA) in accordance
with the quality assurance requirements of section 5.1.1 of 40 CFR
part 60, appendix F. Each SO2 and diluent CEMs shall be subject to
cylinder gas audits (OGA) in accordance with the quality assurance
requirements of section 5.1.2 of appendix F with the exception that
any SO2 or diluent CEMs without any type of probe or sample line
shall be exempt from the OGA requirements.
5. Recordkeeping Requirements
5.1 The plant owner or operator shall keep a record of each
hourly emission rate, each hourly SO2 CEMs value and hourly flow
rate value, and each hourly Btu heat input rate, hourly steam rate,
or hourly electrical power output, and a record of each hourly
weighted average emission rate. These records shall be kept for all
periods of operation of Unit 1 or 2 under provisions of § 60.43(e),
including operations of Unit 1 (E1) during periods of DAFGDS
startup, shutdown, and malfunction when H1 and E1 are assumed to be
zero (0) (see 4.5).
5.2 The plant owner or operator shall keep a record of each
hourly gas flow rate through the DAFGDS stack, each hourly stack
gas flow rate through the bypass stack during any periods that the
DAFGDS bypass damper is opened or flow is indicated, and reason for
bypass operation.
6. Reporting Requirements
6.1 The owner or operator of any affected facility shall submit
the written reports required under 6.2 of this section and subpart
A to the Regional Administrator of the USEPA, Region 5 and the
Director, of the IEPA for every calendar quarter. All quarterly
reports shall be submitted by the 30th day following the end of
each calendar quarter.
6.2 For sulfur dioxide, the following data resubmitted to the
Regional Administrator of the USEPA, Region 5 and the Director, of
the IEPA for each 24-hour period:
6.2.1 Calendar date
6.2.2 The combined average sulfur dioxide emission rate (ng/J or
lb/million Btu) for the past 30 successive boiler operating days
(ending with the last 30-day period in the quarter); and, for any
noncompliance periods, reasons for noncompliance with the emission
standards and description of corrective action taken.
6.2.3 Identification of the boiler operating days for which
valid sulfur dioxide emissions data required by 4.6 have not been
obtained for 75 percent of the boiler operating hours; reasons for
not obtaining sufficient data; and description of corrective
actions taken to prevent recurrence.
6.2.4 Identification of the time periods (hours) when Unit 1 or
Unit 2 were operated but combined hourly emission rates (EC) were
not calculated because of the unavailability of parameters E1, E2,
H1, or H2 as described in 3.2.
6.2.5 Identification of the time periods (hours) when Unit 1 and
Unit 2 were operated and where the combined hourly emission rate
(EC) equalled Unit 2 (E2/H2) emissions because of the Unit 1
malfunction provisions under 3.5.3, and 3.5.4.
6.2.6 Identification of the time periods (hours) when emissions
from the Unit 1 DAFGDS have been excluded from the calculation of
average sulfur dioxide emission rates because of Unit 1 DAFGDS
startup, shutdown, malfunction, or other reasons; and justification
for excluding data for reasons other than startup or shutdown.
Reporting of hourly emission rate of Unit 1 (E1/H2) during each
hour of the DAFGDS startup, malfunction under 3.5.1, 3.5.2, 3.5.3,
and 3.5.4 (see 4.5).
6.2.7 Identification of the number of days in the calendar
quarter that the affected facility was operated (any fuel
fired).
6.2.8 Identify any periods where Unit 1 DAFGDS malfunctions
occurred and the cumulative hours of Unit 1 DAFGDS malfunction for
the quarter.
6.2.9 Identify any periods of time that any exhaust gases were
discharged to the DAFGDS bypass stack and the hourly gas flow rate
through the DAFGDS stack and through the DAFGDS bypass stack during
such periods and reason for bypass operation.
6.2.10 [Reserved]
[52 FR 28955, Aug. 4, 1987, as amended at 58 FR 28785, May 17,
1993; 59 FR 8135, Feb. 18, 1994]
Appendix H to Part 60 [Reserved]
40:9.0.1.1.1.0.1.1.15 : Appendix H
Appendix H to Part 60 [Reserved]
Appendix I to Part 60 - Owner's Manuals and Temporary Labels for Wood Heaters Subject to Subparts AAA and QQQQ of Part 60
40:9.0.1.1.1.0.1.1.16 : Appendix I
Appendix I to Part 60 - Owner's Manuals and Temporary Labels for
Wood Heaters Subject to Subparts AAA and QQQQ of Part 60 1.
Introduction
The purpose of this appendix is to provide specific instructions
and examples to manufacturers for compliance with the owner's
manual provisions of subparts AAA and QQQQ of this part.
2. Instructions for Preparation of Wood Heater Owner's Manuals
2.1 Introduction
Although the owner's manuals do not require premarket approval,
EPA will monitor the contents to ensure that sufficient information
is included to provide heater proper operation and maintenance
information affecting emissions to consumers. The manufacturer must
make current and historical owner's manuals available on the
company Web site and upon request to the EPA. The purpose of this
section is to provide instructions to manufacturers for compliance
with the owner's manual provisions of § 60.536(g) of subpart AAA
that applies to wood heaters and § 60.5478(f) of subpart QQQQ that
applies to hydronic heaters and forced-air furnaces. A checklist of
topics and illustrative language is provided as instructions.
Owner's manuals should be tailored to specific wood heater models,
as appropriate.
2.2 Topics Required To Be Addressed in Owner's Manual
(a) Wood heater description and compliance status;
(b) Tamper warnings;
(c) Overall heater warranty information and catalyst information
and warranty (if catalyst-equipped);
(d) Fuel selection;
(e) Achieving and maintaining catalyst light-off (if
catalyst-equipped);
(i) Wood heater proper operation and maintenance, including
minimizing visible emissions;
(j) Wood heater proper installation, including location, stack
height and achieving proper draft;
(k) Use of smoke detectors and carbon monoxide monitors; and
(l) Efficiency.
2.3 Sample Text/Descriptions
(a) The following are example texts and/or further descriptions
illustrating the topics identified above. Although the regulation
requires manufacturers to address (where applicable) the 10 topics
identified above, the exact language is not specified. Manuals
should be written specific to the model and design of the wood
heater. The following instructions are composed of generic
descriptions and texts.
(b) If manufacturers choose to use the language provided in the
example, the portion in italics should be revised as appropriate.
Any manufacturer electing to use the EPA example language will be
considered to be in compliance with owner's manual requirements
provided that the particular language is printed in full with only
such changes as are necessary to ensure accuracy.
Example language is not provided for certain topics, since these
areas are generally heater specific. For these topics,
manufacturers should develop text that is specific to the proper
operation and maintenance of their particular products.
2.3.1 Wood Heater Description and Compliance Status
Owner's manuals must include:
(a) Manufacturer and model;
(b) Compliance status (2015 standard, 2016 standard, 2017
standard, 2020 standard, crib wood standard or cord wood
alternative standard, last allowable sell date, etc.); and
(c) Heat output range.
Exhibit 1 - Example Text covering 2.3.1(a), (b), and (c) of this
appendix:
“This manual describes the installation and operation of the
Brand X, Model 0 catalytic equipped wood heater. This heater meets
the 2015 U.S. Environmental Protection Agency's crib wood
emission limits for wood heaters sold after May 15, 2015. Under
specific test conditions this heater has been shown to deliver heat
at rates ranging from 8,000 to 35,000 Btu/hr.”
2.3.2 Tamper Warnings
(a) The following statement must be included in the owner's
manual for all units:
“This wood heater has a manufacturer-set minimum low burn rate
that must not be altered. It is against federal regulations to
alter this setting or otherwise operate this wood heater in a
manner inconsistent with operating instructions in this
manual.”
(b) The following statement must be included in the owner's
manual for catalyst-equipped units:
“This wood heater contains a catalytic combustor, which needs
periodic inspection and replacement for proper operation. It is
against federal regulations to operate this wood heater in a manner
inconsistent with operating instructions in this manual, or if the
catalytic element is deactivated or removed.”
2.3.3 Overall Heater Warranty Information and Catalyst Information
and Warranty (if catalyst-equipped)
The following information must be included with or supplied in
the owner's and warranty manuals:
(a) Manufacturer and model, including catalyst if
catalyst-equipped;
(b) Warranty details, including catalyst if catalyst-equipped;
and
(c) Instructions for warranty claims.
Exhibit 2 - Example Text covering 2.3.3(a), (b), and (c) of this
appendix for catalysts:
“The combustor supplied with this heater is a Brand Z, Long
Life Combustor. Consult the catalytic combustor warranty also
supplied with this wood heater. Warranty claims should be addressed
to:
Stove or Catalyst Manufacturer Address Phone #______________”
2.3.3.1 This section should also provide clear instructions on
how to exercise the warranty (how to package parts for return
shipment, etc.).
2.3.4 Fuel Selection
Owner's manuals must include:
(a) Instructions on acceptable fuels;
(b) Warning against inappropriate fuels; and
(c) How to determine seasoned wood compared to unseasoned wood,
how to use moisture meters and other techniques and the importance
of seasoned wood.
Exhibit 3 - Example Text covering 2.3.4(a) and (b) of this
appendix:
“This heater is designed to burn natural wood only. Higher
efficiencies and lower emissions generally result when burning air
dried seasoned hardwoods, as compared to softwoods or to green or
freshly cut hardwoods. DO NOT BURN:
(1) Garbage;
(2) Lawn clippings or yard waste;
(3) Materials containing rubber, including tires;
(4) Materials containing plastic;
(5) Waste petroleum products, paints or paint thinners, or
asphalt products;
(6) Materials containing asbestos;
(7) Construction or demolition debris;
(8) Railroad ties or pressure-treated wood;
(9) Manure or animal remains;
(10) Salt water driftwood or other previously salt water
saturated materials;
(11) Unseasoned wood; or
(12) Paper products, cardboard, plywood, or particleboard. The
prohibition against burning these materials does not prohibit the
use of fire starters made from paper, cardboard, saw dust, wax and
similar substances for the purpose of starting a fire in an
affected wood heater.
Burning these materials may result in release of toxic fumes or
render the heater ineffective and cause smoke.”
2.3.5 Achieving and Maintaining Catalyst Light-Off
Owner's manuals must describe in detail proper procedures
for:
(a) Operation of catalyst bypass (stove specific);
(b) Achieving catalyst light-off from a cold start; and
(c) Achieving catalyst light-off when refueling.
2.3.5.1 No example text is supplied for describing operation of
catalyst bypass mechanisms (Item 2.3.5(a) of this appendix) since
these are typically stove-specific. Manufacturers must provide
instructions specific to their model describing:
(1) Bypass position during startup;
(2) Bypass position during normal operation; and
(3) Bypass position during reloading.
Exhibit 4 - Example Text for Item 2.3.5(b) of this appendix:
“The temperature in the stove and the gases entering the
combustor must be raised to between 500° to 700 °F
for catalytic activity to be initiated. During the startup of a
cold stove, a medium to high firing rate must be maintained for
about 20 minutes. This ensures that the stove, catalyst, and
fuel are all stabilized at proper operating temperatures. Even
though it is possible to have gas temperatures reach 600 °F
within 2 to 3 minutes after a fire is started, if the
fire is allowed to die down immediately, it may go out or the
combustor may stop working. Once the combustor starts working, heat
generated in it by burning the smoke will keep it working.”
Exhibit 5 - Example Text for Item 2.3.5(c) of this appendix:
“REFUELING: During the refueling and rekindling of a cool fire,
or a fire that has burned down to the charcoal phase, operate the
stove at a medium to high firing rate for about 10 minutes
to ensure that the catalyst reaches approximately 600
°F.”
2.3.6 Catalyst Monitoring
Owner's manuals must include:
(a) Recommendation to visually inspect combustor at least three
times during the heating season;
(b) Discussion on expected combustor temperatures for
monitor-equipped units; and
(c) Suggested monitoring and inspection techniques and
importance of ensuring catalyst is operating properly.
Exhibit 6 - Example Text covering 2.3.6(a), (b) and (c) of this
appendix:
“It is important to periodically monitor the operation of the
catalytic combustor to ensure that it is functioning properly and
to determine when it needs to be replaced. A non-functioning
combustor will result in a loss of heating efficiency, and an
increase in creosote and emissions. Following is a list of items
that should be checked on a periodic basis:
• Combustors should be visually inspected at least three times
during the heating season to determine if physical degradation has
occurred. Actual removal of the combustor is not recommended unless
more detailed inspection is warranted because of decreased
performance. If any of these conditions exists, refer to Catalyst
Troubleshooting section of this owner's manual.
• This catalytic (or hybrid) heater is equipped with a
temperature probe to monitor catalyst operation. Properly
functioning combustors typically maintain temperatures in excess of
500 °F, and often reach temperatures in excess of
1,000 °F. If catalyst temperatures are not in excess of
500 °F, refer to Catalyst Troubleshooting section of this
owner's manual.
• You can get an indication of whether the catalyst is working
by comparing the amount of smoke leaving the chimney when the smoke
is going through the combustor and catalyst light-off has been
achieved, to the amount of smoke leaving the chimney when the smoke
is not routed through the combustor (bypass mode).
Step 1 - Light stove in accordance with instructions in section
3.3.5.
Step 2 - With smoke routed through the catalyst, go outside and
observe the emissions leaving the chimney.
Step 3 - Engage the bypass mechanism and again observe the
emissions leaving the chimney.
Significantly more smoke will be seen when the exhaust is not
routed through the combustor (bypass mode).”
2.3.7 Catalyst Troubleshooting
The owner's manual must provide clear descriptions of symptoms
and remedies to common combustor problems and importance. It is
recommended that photographs of catalyst peeling, plugging, thermal
cracking, mechanical cracking, and masking be included in the
manual to aid the consumer in identifying problems and to provide
direction for corrective action.
2.3.8 Catalyst Replacement
The owner's manual must provide clear step-by-step instructions
on how to remove and replace the catalytic combustor. The section
should include diagrams and/or photographs.
2.3.9 Wood Heater Proper Operation and Maintenance
The owner's manual must provide clear descriptions of symptoms
and remedies to common heater problems and importance. The owner's
manual information must be adequate to enable consumers to achieve
optimal emissions performance. Such information must be consistent
with the operating instructions provided by the manufacturer to the
approved test laboratory for operating the wood heater during
certification testing, except for details of the certification test
that would not be relevant to the user.
Owner's manual must include:
(a) Recommendations about building and maintaining a fire,
especially for cold starts and the effectiveness of the top-down
approach for starting fires;
(b) Instruction on proper use of air controls, including how to
establish good combustion and how to ensure good combustion at the
lowest burn rate for which the heater is warranted;
(c) Ash removal and disposal;
(d) Instruction replacement of gaskets, air tubes and other
parts that are critical to the emissions performance of the unit,
and other maintenance and repair instructions;
(e) Warning against overfiring; and
(f) Suggested monitoring and inspection techniques and
importance of ensuring heater is operating properly, including
ensuring visible emissions are minimized.
2.3.9.1 No example text is supplied for 2.3.9(a), (b), (d) and
(f) of this appendix since these items are model specific.
Manufacturers should provide detailed instructions on building and
maintaining a fire including selection of fuel pieces, fuel
quantity and stacking arrangement. Manufacturers should also
provide instruction on proper air settings (both primary and
secondary) for attaining minimum and maximum heat outputs and any
special instructions for operating thermostatic controls.
Step-by-step instructions on inspection and replacement of gaskets
should also be included. Manufacturers should provide diagrams
and/or photographs to assist the consumer. Gasket type and size
should be specified.
Exhibit 7 - Example Text for Item 2.3.9(c) of this appendix:
“Whenever ashes get 3 to 4 inches deep in your
firebox or ash pan, and when the fire has burned down and cooled,
remove excess ashes. Leave an ash bed approximately 1 inch
deep on the firebox bottom to help maintain a hot charcoal
bed.”
“Ashes should be placed in a metal container with a
tight-fitting lid. The closed container of ashes should be placed
on a noncombustible floor or on the ground, away from all
combustible materials, pending final disposal. The ashes should be
retained in the closed container until all cinders have thoroughly
cooled.”
Exhibit 8 - Example Text covering Item 2.3.9(e) of this
appendix:
“DO NOT OVERFIRE THIS HEATER”
“Attempts to achieve heat output rates that exceed heater design
specifications can result in permanent damage to the heater and to
the catalytic combustor if so equipped.”
2.3.10 Wood Heater Installation, Including Stack Height, Heater
Locations and Achieving Proper Draft
Owner's manual must include:
(a) Importance of proper draft;
(b) Conditions indicating inadequate draft;
(c) Conditions indicating excessive draft; and
(d) Guidance on proper stack height and proper heater locations,
i.e., not too close to neighbors or in valleys that would
cause unhealthy air quality or nuisance conditions.
2.3.10.1 No example text is supplied for (d) because state,
local and tribal requirements are model and location specific.
Exhibit 9 - Example Text for Item (a):
“Draft is the force which moves air from the appliance up
through the chimney. The amount of draft in your chimney depends on
the length of the chimney, local geography, nearby obstructions and
other factors. Too much draft may cause excessive temperatures in
the appliance and may damage the catalytic combustor. Inadequate
draft may cause backpuffing into the room and 'plugging' of the
chimney or the catalyst.”
Exhibit 10 - Example Text for Item (b):
“Inadequate draft will cause the appliance to leak smoke into
the room through appliance and chimney connector joints.”
Exhibit 11 - Example Text for Item (c):
“An uncontrollable burn or excessive temperature indicates
excessive draft.”
2.3.11 Efficiency
Owner's manual must include:
(a) Description of how the efficiency was determined,
e.g., use higher heating value of the fuel instead of lower
heating value of the fuel, discuss sweet spot versus annual average
versus annual fuel usage efficiency (AFUE);
(b) How operation and fuels affect efficiency, e.g.,
seasoned wood versus high moisture fuel; operation at sweet spot
versus low-burn rates; and
(c) How location affects the efficiency, e.g., in main
living area versus basement versus outdoors in sub-freezing
temperatures.
2.3.12 Smoke and Carbon Monoxide Emissions and Monitors
Owner's manual must include:
(a) Discussion of smoke and carbon monoxide (CO) emissions,
including the CO data submitted in the certification application
and expected variations for different operating conditions;
(b) Recommendation to have smoke monitors; and
(c) Recommendation to have monitors for areas that are expected
to generate CO, e.g., heater fueling areas, pellet fuel bulk
storage areas, sheds containing hydronic heaters.
3. Instructions for Preparation of Wood Heater Temporary Labels
3.1 Temporary labels that show the values for emissions,
efficiency, recommended heating area and the compliance status may
(voluntarily) be affixed by the manufacturer to wood heaters that
meet the 2020 particulate matter emission standards early or that
meet the cord wood alternative compliance options in subparts AAA
and QQQQ of this part.
3.2 The seller of each heater covered by section 3.1 may ensure
that the temporary label remains affixed until each heater is
purchased by the end user.
3.3 The temporary label option for the 2020 particulate matter
emission standards end as of May 15, 2020.
3.4 The template for the temporary labels will be supplied by
the Administrator upon request.