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Table 4 to Subpart DDDD of Part 63—Requirements for Performance Tests

Requirements for Performance Tests

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  5. Chapter I
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  9. Subpart DDDD
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  11. Subject Group Other Requirements and Information
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  13. Appendix Table 4 to Subpart DDDD of Part 63
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Displayed edition2026-07-09
Last updated2026-07-09

Table 4 to Subpart DDDD of Part 63—Requirements for Performance Tests

Table 4 to Subpart DDDD of Part 63—Requirements for Performance Tests

For . . .You must . . .Using . . .
(1) Each process unit subject to a compliance option in tables 1A through 1E to this subpartselect sampling port's location and the number of traverse portsEPA Method 1 or 1A of appendix A-1 to part 60 of this chapter (as appropriate).
(2) Each process unit subject to a compliance option in tables 1A through 1E to this subpartdetermine velocity and volumetric flow rateEPA Method 2 in addition to Methods 2A, 2C, 2D, 2F, or 2G of appendices A-1 and A-2 to part 60 of this chapter (as appropriate).
(3) Each process unit subject to a compliance option in tables 1A through 1E to this subpartconduct gas molecular weight analysisEPA Method 3, 3A, or 3B of appendix A-2 to part 60 of this chapter (as appropriate). As an alternative to EPA Method 3B for the manual procedures only and not the instrumental procedures, you may use ANSI/ASME PTC 19-10-1981 Part 10 (IBR, see § 63.14).
(4) Each process unit subject to a compliance option in tables 1A through 1E to this subpartmeasure moisture content of the stack gasEPA Method 4 of appendix A-3 to part 60 of this chapter; OR EPA Method 320 of appendix A to this part; OR ASTM D6348-12e1 (IBR, see § 63.14).
(5) Each process unit subject to a compliance option in table 1B to this subpart for which you choose to demonstrate compliance using a total HAP as THC compliance optionmeasure emissions of total HAP as THCEPA Method 25A in appendix A-7 to part 60 of this chapter. You may measure emissions of methane using EPA Method 18 in appendix A-6 to part 60 of this chapter and subtract the methane emissions from the emissions of total HAP as THC.
(6) Each process unit subject to a compliance option in table 1A to this subpartmeasure emissions of total HAP (as defined in § 63.2292)EPA Method 320 of appendix A to this part; OR the NCASI Method IM/CAN/WP-99.02 (IBR, see § 63.14); OR the NCASI Method ISS/FP-A105.01 (IBR, see § 63.14); OR ASTM D6348-12e1 (IBR, see § 63.14) provided that the conditions in footnote “1” are met.
(7) Each process unit subject to a compliance option in table 1B to this subpart for which you choose to demonstrate compliance using a methanol compliance optionmeasure emissions of methanolEPA Method 308 of appendix A to this part; OR EPA Method 320 of appendix A to this part; OR the NCASI Method CI/WP-98.01 (IBR, see § 63.14); OR the NCASI Method IM/CAN/WP-99.02 (IBR, see § 63.14); OR the NCASI Method ISS/FP-A105.01 (IBR, see § 63.14).
(8) Each process unit subject to a compliance option in table 1B to this subpart for which you choose to demonstrate compliance using a formaldehyde compliance optionmeasure emissions of formaldehydeEPA Method 316 of appendix A to this part; OR EPA Method 320 of appendix A to this part; OR EPA Method 0011 in “Test Methods for Evaluating Solid Waste, Physical/Chemical Methods” (EPA Publication No. SW-846) for formaldehyde (IBR, see § 63.14); OR the NCASI Method CI/WP-98.01 (IBR, see § 63.14); OR the NCASI Method IM/CAN/WP-99.02 (IBR, see § 63.14); OR the NCASI Method ISS/FP-A105.01 (IBR, see § 63.14).
(9) Each reconstituted wood product press at a new or existing affected source or reconstituted wood product board cooler at a new affected source subject to a compliance option in table 1B to this subpartmeet the design specifications included in the definition of wood products enclosure in § 63.2292; or

determine the percent capture efficiency of the enclosure directing emissions to an add-on control device		EPA Methods 204 and 204A through 204F of appendix M to part 51 of this chapter, to determine capture efficiency (except for wood products enclosures as defined in § 63.2292). Enclosures that meet the definition of wood products enclosure or that meet Method 204 requirements for a permanent total enclosure (PTE) are assumed to have a capture efficiency of 100 percent. Enclosures that do not meet either the PTE requirements or design criteria for a wood products enclosure must determine the capture efficiency by constructing a TTE according to the requirements of EPA Method 204 and applying EPA Methods 204A through 204F (as appropriate). As an alternative to EPA Methods 204 and 204A through 204F, you may use the tracer gas method contained in appendix A to this subpart.
(10) Each reconstituted wood product press at a new or existing affected source or reconstituted wood product board cooler at a new affected source subject to a compliance option in table 1A to this subpartdetermine the percent capture efficiencyA TTE and EPA Methods 204 and 204A through 204F (as appropriate) of appendix M to part 51 of this chapter. As an alternative to installing a TTE and using EPA Methods 204 and 204A through 204F, you may use the tracer gas method contained in appendix A to this subpart. Enclosures that meet the design criteria (1) through (4) in the definition of wood products enclosure, or that meet EPA Method 204 requirements for a PTE (except for the criteria specified in section 6.2 of EPA Method 204) are assumed to have a capture efficiency of 100 percent. Measured emissions divided by the capture efficiency provides the emission rate.
(11) Each process unit subject to a compliance option in tables 1A and 1B to this subpartestablish the site-specific operating requirements (including the parameter limits or THC concentration limits) in table 2 to this subpartData from the parameter monitoring system or THC CEMS and the applicable performance test method(s).
(12) Each process unit subject to total HAP limit in table 1C to this subpartmeasure emissions of total HAP (as defined in § 63.2292)EPA Method 320 of appendix A to this part; OR the NCASI Method IM/CAN/WP-99.02 (IBR, see § 63.14); OR the NCASI Method ISS/FP-A105.01 (IBR, see § 63.14); OR ASTM D6348-12e1 (IBR, see § 63.14) provided that the conditions in footnote “1” are met. Nondetect data must be treated according to § 63.2262(g)(3).
(13) Each process unit subject to an MDI limit in table 1C to this subpartmeasure emissions of MDIEPA Method 326 of appendix A to this part. Nondetect data must be treated according to § 63.2262(g)(3). A minimum sample volume of 1 dscm must be collected.
(14) Each process unit subject to a PM HAP metals limit in table 1D or 1E to this subpartmeasure emissions of PMEPA Method 5 in appendix A-3 to part 60 of this chapter; or EPA Method 29 in appendix A-8 to part 60 of this chapter. Nondetect data must be treated according to § 63.2262(g)(3). A minimum sample volume of 2 dscm must be collected.
(15) Each process unit subject to a mercury limit in table 1D or 1E to this subpartmeasure emissions of mercuryEPA Method 29 or 30B in appendix A-8 to part 60 of this chapter. Nondetect data must be treated according to § 63.2262(g)(3). For EPA Method 29 a minimum sample volume of 2 dscm must be collected.
(16) Each process unit subject to an HCl limit in table 1D or 1E to this subpartmeasure emissions of HClEPA Method 26A in appendix A-8 to part 60 of this chapter. Nondetect data must be treated according to § 63.2262(g)(3). A minimum sample volume of 2 dscm must be collected.
(17) Each process unit subject to a PAH limit in table 1D or 1E to this subpart and each direct wood-fired softwood veneer dryer subject to this subpartmeasure emissions of PAHEPA Method 23 of appendix A-8 to part 60 of this chapter. Nondetect data must be treated according to § 63.2262(g)(3). A minimum sample volume of 3 dscm must be collected.
(18) Each process unit subject to a PM limit in table 1D or table 1E to this subpart controlled by mechanical collector or other dry control device for which pressure drop and opacity observations are used to demonstrate complianceobserve opacityMethod 9 of appendix A-4 to part 60 of this chapter. Opacity observations must be conducted during the duration of the PM performance test. For weekly observations, two 6-minute readings are required.
(19) Each direct wood-fired green rotary dryer subject to a dioxin/furan TEQ limit in § 63.2240(d)(3) or (4)Measure emissions of dioxins and furansEPA Method 23 of appendix A-8 to part 60 of this chapter. Nondetect and estimated maximum possible concentration (EMPC) data must be treated according to § 63.2262(g)(3) and section 9.1.7.2 of EPA Method 23 procedures for standards promulgated after March 20, 2023. A minimum sample volume of 3 dscm must be collected. For each dioxin and furan congener, multiply the congener concentration by its corresponding toxic equivalency factor specified in table 12 to this subpart to determine the TEQ concentration for each congener. Sum the TEQ concentrations of each congener to obtain the total concentration of dioxins and furans emitted in terms of TEQ.
dscm = dry standard cubic meters.
1 As an alternative to EPA Method 320 of appendix A to this part, you may use ASTM Method D6348-12e1 (incorporated by reference, see § 63.14), with the caveats that the test plan preparation and implementation in the Annexes to ASTM Method D6348-12el, Sections Al through A8 are mandatory; and in ASTM Method D6348-12e1 Annex A5 (Analyte Spiking Technique), the percent (%) R must be determined for each target analyte (Equation A5.5). In order for the test data to be acceptable for a compound, %R must be 70% ≤ R ≤ 130%. If the %R value does not meet this criterion for a target compound, the test data is not acceptable for that compound and the test must be repeated for that analyte (i.e., the sampling and/or analytical procedure should be adjusted before a retest). The %R value for each compound must be reported in the test report, and all field measurements must be corrected with the calculated %R value for that compound by using the following equation:
Reported Results = (Measured Concentration in the Stack × 100)/% R.

[91 FR 41452, July 6, 2026]