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Title 7 Part 51 → Subpart

Title 7 → Subtitle B → Chapter I → Subchapter C → Part 51 → Subpart

Electronic Code of Federal Regulations e-CFR

Title 7 Part 51 → Subpart

e-CFR data is current as of December 5, 2019

Title 7Subtitle BChapter ISubchapter CPart 51 → Subpart


Title 7: Agriculture
PART 51—FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS (INSPECTION, CERTIFICATION, AND STANDARDS)


Subpart—United States Standards for Grades of Potatoes1

Grades

§51.1540   [Reserved]

§51.1541   U.S. No. 1.

“U.S. No. 1” consists of potatoes which meet the following requirements:

(a) Similar varietal characteristics, except when designated as a mixed or specialty pack;

(b) Firm;

(c) Fairly clean;2

2Potatoes in containers bearing official State Seed Certification Tags and Seals are not required to be fairly clean but shall be free from damage by dirt.

(d) Fairly well shaped;

(e) Free from:

(1) Freezing;

(2) Blackheart;

(3) Late blight, southern bacterial wilt and ring rot; and,

(4) Soft rot and wet breakdown.

(f) Free from damage by any other cause. See §§51.1564 and 51.1565.

(g) Size. Not less than 178 inches in diameter, unless otherwise specified in connection with the grade.

(h) For tolerances see §51.1546.

[35 FR 18258, Dec. 1, 1970, as amended at 76 FR 31789, June 2, 2011]

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§51.1542   U.S. Commercial.

“U.S. Commercial” consists of potatoes which meet the requirements of U.S. No. 1 grade except for the following:

(a) Free from serious damage caused by:

(1) Dirt or other foreign matter;

(2) Russet scab; and,

(3) Rhizoctonia.

(b) Increased tolerances for defects specified in §51.1546.

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§51.1543   U.S. No. 2.

“U.S. No. 2” consists of potatoes which meet the following requirements:

(a) Similar varietal characteristics, except when designated as a mixed or specialty pack;

(b) Not seriously misshapen;

(c) Free from:

(1) Freezing;

(2) Blackheart;

(3) Late blight, southern bacterial wilt and ring rot; and,

(4) Soft rot and wet breakdown.

(d) Free from serious damage by any other cause. See §§51.1564 and 51.1565.

(e) Size. Not less than 112 inches in diameter, unless otherwise specified in connection with the grade.

(f) For tolerances see §51.1546.

[35 FR 18258, Dec. 1, 1970, as amended at 76 FR 31789, June 2, 2011]

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Unclassified

§51.1544   [Reserved]

§51.1545   Size.

(a) The minimum size, or minimum and maximum sizes may be specified in connection with the grade in terms of diameter or weight of the individual potato, or in accordance with one of the size designations in Table I or Table II: Provided, That sizes so specified shall not be in conflict with the basic size requirements for the grade.

(b) When size is designated as shown in Table II, the corresponding weight ranges shall apply. These size designations may be applied to potatoes packed in any size container: Provided, that the weight ranges are within the limits specified.

Table 1

Size designation Minimum diameter1
or weight
Maximum diameter1
or weight
InchesOuncesInches Ounces
Creamer 34 (3)158 (3)
Chef234 8412 28
Size A2178 (3)(3)(3)
Size B112 (3)214 (3)
Small134 (3)212 6
Medium214 5314 10
Large310412 28

1Diameter means the greatest dimension at right angles to the longitudinal axis, without regard to the position of the stem end.

2In addition to the minimum size specified, a lot of potatoes designated as Size A shall contain at least 40 percent of potatoes which are 212 inches in diameter or larger or 6 ounces in weight or larger.

3No requirement.

Table II

[Ounces]

Size designationMinimum weightMaximum weight
Under 5015
501219
601016
70915
80813
90712
100610
11059
12048
13048
14048
Over 14048

[35 FR 18258, Dec. 1, 1970, as amended at 37 FR 2745, Feb. 5, 1972. Redesignated at 42 FR 32514, June 27, 1977, and further redesignated at 46 FR 63203, Dec. 31, 1981; amended at 56 FR 7553, Feb. 25, 1991; 73 FR 15055, Mar. 21, 2008; 73 FR 70585, Nov. 21, 2008]

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Tolerances

§51.1546   Tolerances.

To allow for variations incident to proper grading and handling in each of the foregoing grades, the following tolerances by weight or equivalent basis, are provided as specified.

(a) For defects—(1) U.S. No. 1. (i) At Shipping Point: A total of 8 percent for potatoes in any lot which fail to meet the requirements for the grade: Provided, That included in this tolerance not more than the following percentages shall be allowed for the defects listed:

(A) 5 percent for external defects;

(B) 5 percent for internal defects; and

(C) Not more than a total of 1 percent for potatoes which are frozen or affected by soft rot or wet breakdown. See §51.1547.

(ii) En route or at destination: A total of 10 percent for potatoes in any lot which fail to meet the requirements for the grade: Provided, That included in this tolerance not more than a total of 8 percent shall be allowed for permanent defects: And provided further, the following percentages shall be allowed for the defects listed:

(A) 7 percent for external defects, including therein not more than 5 percent for permanent external defects;

(B) 7 percent for internal defects, including therein not more than 5 percent for permanent internal defects; and

(C) Not more than a total of 2 percent for potatoes which are frozen or affected by soft rot or wet breakdown. See §51.1547.

(2) U.S. Commercial: A total of 20 percent for potatoes in any lot which fail to meet the requirements for the grade: Provided, That included in this tolerance not more than the following percentages shall be allowed for the defects listed:

(i) 10 percent for potatoes which fail to meet the requirements for U.S. No. 2 grade, including therein not more than:

(ii) 6 percent for external defects;

(iii) 6 percent for internal defects; and

(iv) Not more than a total of 1 percent for potatoes which are frozen or affected by soft rot or wet breakdown. See §51.1547.

(3) U.S. No. 2. (i) At Shipping Point: A total of 10 percent for potatoes in any lot which fail to meet the requirements for the grade: Provided, That included in this tolerance not more than the following percentages shall be allowed for the defects listed:

(A) 6 percent for external defects;

(B) 6 percent for internal defects; and

(C) Not more than a total of 1 percent for potatoes which are frozen or affected by soft rot or wet breakdown. See §51.1547.

(ii) En route or at destination: A total of 12 percent for potatoes in any lot which fail to meet the requirements for the grade: Provided, That included in this tolerance not more than a total of 10 percent shall be allowed for permanent defects: And provided further, the following percentages shall be allowed for the defects listed:

(A) 8 percent for external defects, including therein not more than 6 percent for permanent external defects;

(B) 8 percent for internal defects, including therein not more than 6 percent for permanent internal defects; and

(C) Not more than a total of 2 percent for potatoes which are frozen or affected by soft rot or wet breakdown. See §51.1547.

(b) For off-size. (1) Not more than 3 percent of the potatoes in any lot may be smaller than the required or specified minimum size except that a tolerance of 5 percent shall be allowed for potatoes packed to meet a minimum size of 214 inches or larger in diameter or 5 ounces or more in weight. In addition, not more than 10 percent may be larger than any required or specified maximum size. See §51.1547.

(2) When a percentage of the potatoes is specified to be of a certain size and larger, individual samples shall have not less than one-half of the percentage specified: Provided, That the average for the entire lot is not less than the percentage specified.

[35 FR 18258, Dec. 1, 1970. Redesignated at 42 FR 32514, June 27, 1977, and further redesignated at 46 FR 63203, Dec. 31, 1981; amended at 56 FR 7553, Feb. 25, 1991; 73 FR 15055, Mar. 21, 2008; 73 FR 70585, Nov. 21, 2008; 76 FR 31789, June 2, 2011]

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Application of Tolerances

§51.1547   Application of tolerances.

Individual samples shall have not more than double the tolerances specified, except that at least one defective and one off-size potato may be permitted in any sample: Provided, That en route or at destination one-tenth of the samples may contain three times the tolerance permitted for potatoes which are frozen or affected by soft rot or wet breakdown: And provided further, That the averages for the entire lot are within the tolerances specified for the grade.

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Samples for Grade and Size Determination

§51.1548   Samples for grade and size determination.

Individual samples shall consist of at least 20 pounds. When individual packages contain at least 20 pounds, each individual sample is drawn from one package; when packages contain less than 20 pounds, a sufficient number of adjoining packages are opened to provide at least a 20-pound sample. The number of such individual samples drawn for grade and size determination will vary with the size of the lot.

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Skinning

§51.1549   Skinning.

(a) The following definitions provide a basis for describing lots of potatoes as to the degree of skinning whenever description may be appropriate:

(1) “Practically no skinning” means that not more than 5 percent of the potatoes in the lot have more than one-tenth of the skin missing or “feathered”;

(2) “Slightly skinned” means that not more than 10 percent of the potatoes in the lot have more than one-fourth of the skin missing or “feathered”;

(3) “Moderately skinned” means that not more than 10 percent of the potatoes in the lot have more than one-half of the skin missing or “feathered”; and

(4) “Badly skinned” means that more than 10 percent of the potatoes in the lot have more than one-half of the skin missing or “feathered”.

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Definitions

§51.1550   Similar varietal characteristics.

Similar varietal characteristics means that the potatoes in any lot have the same general shape, color and character of skin, and color of flesh.

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§51.1551   Firm.

Firm means that the potato is not shriveled or flabby.

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§51.1552   Clean.

Clean means that at least 90 percent of the potatoes in any lot are practically free from dirt or staining and practically no loose dirt or other foreign matter is present in the container.

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§51.1553   Fairly clean.

Fairly clean means that at least 90 percent of the potatoes in any lot are reasonably free from dirt or staining and not more than a slight amount of loose dirt or foreign matter is present in the container.

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§51.1554   Mature.

Mature means that the skins of the potatoes are generally firmly set and not more than 5 percent of the potatoes in the lot have more than one-tenth of the skin missing or “feathered.”

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§51.1555   Fairly well matured.

Fairly well matured means that the skins of the potatoes are generally fairly firmly set and not more than 10 percent of the potatoes in the lot have more than one-fourth of the skin missing or “feathered.”

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§51.1556   Well shaped.

Well shaped means that the potato has the normal shape for the variety.

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§51.1557   Fairly well shaped.

Fairly well shaped means that the potato is not materially pointed, dumbbell-shaped or otherwise materially deformed.

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§51.1558   Seriously misshapen.

Seriously misshapen means that the potato is seriously pointed, dumbell-shaped or otherwise badly deformed.

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§51.1559   [Reserved]

§51.1560   Damage.

“Damage” means any defect, or any combination of defects, which materially detracts from the edible or marketing quality, or the internal or external appearance of the potato, or any external defect which cannot be removed without a loss of more than 5 percent of the total weight of the potato. See Tables III, IV, V and VI in §51.1564 and Table VII in §51.1565.

[76 FR 31789, June 2, 2011]

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§51.1561   Serious damage.

“Serious damage” means any defect, or any combination of defects, which seriously detracts from the edible or marketing quality, or the internal or external appearance of the potato, or any external defect which cannot be removed without a loss of more than 10 percent of the total weight of the potato. See Tables III, IV, V and VI in §51.1564 and Table VII in 5§1.1565.

[76 FR 31789, June 2, 2011]

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§51.1562   Freezing.

Freezing means that the potato is frozen or shows evidence of having been frozen.

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§51.1563   Soft rot or wet breakdown.

Soft rot or wet breakdown means any soft, mushy, or leaky condition of the tissue such as slimy soft rot, leak, or wet breakdown following freezing injury.

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§51.1564   External defects.

External defects are defects which can be detected externally. However, cutting may be required to determine the extent of the injury. Some external defects are listed in Tables III, IV, V and VI.

Table III—External Defects

DefectsDamageSerious damage1
Air CracksWhen removal causes a loss of more than 5 percent of the total weight of the potato or when the air crack(s) affects more than 13 the length or diameter of the potato (whichever is greater) in the aggregateWhen removal causes a loss of more than 10 percent of the total weight of the potato or when the air crack(s) affects more than 34 the length or diameter of the potato (whichever is greater) in the aggregate.
Artificial ColoringWhen unsightly or when concealing any defect causing damage or when penetrating the flesh and removal causes loss of more than 5 percent of total weight of potatoWhen concealing a serious defect or when penetrating into the flesh and removal causes loss of more than 10 percent of total weight of potato.
Bruises (Not including pressure bruise and sunken discolored areas)When removal causes a loss of more than 5 percent of the total weight of the potato or when the area affected is more than 5 percent of the surface in the aggregate (i.e., 34 inch on a 212 inch or 6 oz. potato). Correspondingly lesser or greater areas in smaller or larger potatoesWhen removal causes a loss of more than 10 percent of the total weight of the potato or when the area affected is more than 10 percent of the surface in the aggregate (i.e., 114 inches on a 212 inch or 6 oz. potato). Correspondingly lesser or greater areas in smaller or larger potatoes.
CutsWhen one smooth cut affects more than 5 percent of the surface areaCut(s) that affect more than 10 percent of the surface area in the aggregate or when a single side cut extends beyond 12 the length of the potato.
DirtWhen materially detracting from the appearance of the potatoWhen seriously detracting from the appearance of the potato.
Elephant HideWhen affecting over 10 percent of the surface area of the potatoWhen affecting over 25 percent of the surface area.
Enlarged LenticelsWhen materially detracting from the appearance of the potatoWhen seriously detracting from the appearance of the potato.
External Discoloration (Areas that are light tan or lighter in color and blends should be ignored)When more than 30 percent of the surface is affected by light tan or light brown colors which do not blend or when more than 15 percent of the surface is affected by colors darker than light tan or light brownWhen more than 60 percent of the surface is affected by light tan or light brown colors which do not blend or when more than 30 percent of the surface is affected by colors darker than light tan or light brown.
Flattened or Depressed Areas/Pressure BruisesWhen removal of underlying discolored flesh causes a loss of more than 5 percent of the total weight of the potato or when the flattened or depressed area(s) covers more surface area than allowed in Table IV. (See Table IV.)When removal of underlying discolored flesh the causes a loss of more than 10 percent of the weight of the potato or when the flattened depressed area(s) covers more surface area than allowed in the Table IV. (See Table IV.)
Flea Beetle InjuryWhen materially detracting from the appearance or when removal causes a loss of more than 5 percent of the total weight of the potato or when the area affected is more than 5 percent of the surface in the aggregateWhen seriously detracting from the appearance of the potato or when removal causes a loss of more than 10 percent of the weight of the potato or when the area affected is more than 10 percent of the surface in the aggregate.
GreeningWhen removal causes a loss of more than 5 percent of the total weight of the potato or when green color affects more than 25 percent of the surface in the aggregateWhen removal causes a loss of more than 10 percent of the weight of the potato or when green color affects more than 50 percent of the surface in the aggregate.
Growth CracksWhen the growth crack(s) affects more than 12 the length of the potato in the aggregate on round varieties or more than 13 the length in the aggregate on long varieties; or, when the depth is greater than that as outlined in Table V. (See Table V.)When the growth crack(s) affects more than 34 the length of the potato in the aggregate or when the depth is greater than that as outlined in Table V. (See Table V.).
Grub DamageWhen removal causes a loss of more than 5 percent of the total weight of the potato or when affecting more than 5 percent of the surface area (i.e. more than 34 inch on a 212 inch or 6 ounce potato). Correspondingly lesser or greater areas in smaller or larger potatoesWhen removal causes a loss of more than 10 percent of the total weight of the potato or when affecting more than 10 percent of the surface area (i.e. more than 114 inch on a 212 inch or 6 ounce potato). Correspondingly lesser or greater areas in smaller or larger potatoes.
Insects or Worms(See Serious Damage.)When present inside the potato.
Nematode (Root Knot)When removal causes loss of more than 5 percent of total weight of potatoWhen removal causes loss of more than 10 percent of total weight of potato.
RhizoctoniaWhen affecting more than 15 percent of the surface in the aggregateWhen affecting more than 50 percent of the surface in the aggregate.
Russeting (On Non Russet Type)When more than 50 percent of the surface is affected in the aggregateN/A.
Rodent or Bird DamageWhen removal causes a loss of more than 5 percent of the total weight of the potato or when affecting more than 5 percent of the surface area (i.e. more than 34 inch on a 212 inch or 6 ounce potato). Correspondingly lesser or greater areas in smaller or larger potatoesWhen removal causes a loss of more than 10 percent of the total weight of the potato or when affecting more than 10 percent of the surface area (i.e. more than 114 inch on a 212 inch or 6 ounce potato). Correspondingly lesser or greater areas in smaller or larger potatoes.
Scab, PittedWhen removal causes a loss of more than 5 percent of the total weight of the potato or when scab affects an aggregate area of more than 12 inch. (Based on a potato 212 inches in diameter or 6 oz. in weight.) Correspondingly lesser or greater areas in smaller or larger potatoesWhen the removal causes a loss of more than 10 percent of the total weight of the potato or when scab affects an aggregate area of more than 1 inch. (Based on a potato 212 inches in diameter or 6 oz. in weight.) Correspondingly lesser or greater areas in smaller or larger potatoes.
Scab, RussetSmooth and affecting more than 13 of the surface or rough russet scab which affects more than 10 percent of the surface in the aggregateRough and affecting more than 25 percent of the surface in the aggregate.
Scab, SurfaceWhen more than 5 percent of the surface in the aggregate is affectedWhen more than 25 percent of the surface in the aggregate is affected.
Second GrowthWhen materially detracting from the appearance of the potatoWhen seriously detracting from the appearance of the potato.
Silver ScurfWhen affecting more than 50 percent of the surface area of the potatoWhen its severity causes a wrinkling of the skin over more than 50 percent of the surface.
SproutsWhen more than 5 percent of the potatoes in any lot have any sprout more than 14 inch in length at shipping point; more than 12 inch in length at destination; or have numerous individual and/or clusters of sprouts which materially detract from the appearance of the potatoWhen more than 10 percent of the potatoes in any lot have any sprout more than 12 inch in length at shipping point; more than 1 inch in length at destination; or have numerous individual and/or clusters of sprouts which seriously detract from the appearance of the potato. Serious damage by sprouts shall only be scored against the U.S. Commercial and U.S. No. 2 grades.
SunburnWhen removal causes loss of more than 5 percent of total weight of potatoWhen removal causes loss more than 10 percent of total weight of potato.
Sunken Discolored AreasSEE TABLE VISEE TABLE VI.
Surface Cracks (Areas affected by fine net-like cracking should be ignored.)When smooth shallow cracking affects more than 13 of the surface or when rough deep cracking affects more than 5 percent of the surfaceWhen rough deep cracking affects more than 10 percent of the surface.
Wireworm or Grass DamageWhen affecting the flesh of the potato and removal causes loss of more than 5 percent of total weight of potato.When affecting the flesh of the potato and removal causes loss of more than 10 percent of total weight of potato.

The following defects are considered serious damage when present in any degree: 1. Freezing. 2. Late blight. 3. Ring rot. 4. Southern bacterial wilt. 5. Soft rot. 6. Wet breakdown.

Table IV—Flattened or Depressed Areas—Pressure Bruises Maximum Area Allowed

Diameter Weight No. 1
(aggregate area)
No. 2
(aggregate area)
Potato is:Potato is:Not more than:Not more than:
Less than 2 inLess than 4 oz 12 in1 in
2 to 212 in4 to 6 oz1 in112 in
More than 212 to 3 inMore than 6 to 8 oz114 in134 in
More than 3 to 312 inMore than 8 to 14 oz112 in178 in
More than 312 to 4 inMore than 14 to 20 oz134 in2 in
More than 4 to 412 inMore than 20 to 28 oz2 in214 in
More than 412 to 5 inMore than 28 to 36 oz214 in234 in
More than 5 inMore than 36 oz212 in314 in

Table V—Depth Allowed for Growth Cracks

Diameter Weight No. 1
(depth)
No. 2
(depth)
Potato is:Potato is:Not more than:Not more than:
Less than 2 inLess than 4 oz 18 in 14 in
2 to 212 in4 oz to 6 oz 14 in 38 in
More than 212 to 3 inMore than 6 oz to 8 oz 38 in 12 in
More than 3 inMore than 8 oz 12 in 58 in

Table VI—Sunken Discolored Areas Maximum Area Allowed

Diameter Weight No. 1
(aggregate area)
No. 2
(aggregate area)
Potato is:Potato is:Not more than:Not more than:
Less than 2 inLess than 4 oz 38 in 34 in
2 to 212 in4 to 6 oz 34 in1 in
More than 212 to 3 inMore than 6 to 8 oz1 in114 in
More than 3 to 312 inMore than 8 to 14 oz114 in112 in
More than 312 to 4 inMore than 14 to 20 oz112 in134 in
More than 4 to 412 inMore than 20 to 28 oz134 in2 in
More than 412 to 5 inMore than 28 to 36 oz2 in214 in
More than 5 inMore than 36 oz214 in212 in

[35 FR 18258, Dec. 1, 1970, as amended at 73 FR 15055, Mar. 21, 2008; 73 FR 70586, Nov. 21, 2008; 76 FR 31789, June 2, 2011]

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§51.1565   Internal defects.

Internal defects are defects which cannot be detected without cutting the potato. Some internal defects are listed in Table VII.

Table VII—Internal Defects

Defects Damage Maximum Allowed Serious Damage Maximum Allowed
Occurring outside of or not entirely confined to the vascular ring
Ingrown Sprouts, Internal Discoloration, Vascular Browning, Fusarium Wilt, Net Necrosis, Other Necrosis, Stem End Browning5 percent waste10 percent waste.
Internal Black SpotWhen the spot(s) are darker than the official color chip (POT-CC-2) after removing 5 percent of the total weight of the potatoWhen the spot(s) are darker than the official color chip (POT-CC-2) after removing 10 percent of the total weight of the potato.
Occurring entirely within the vascular ring
Hollow Heart or Hollow Heart with DiscolorationArea affected not to exceed that of a circle 12 inch in diameter in a potato 212 -inches in diameter or 6 ounces in weight.1Area affected not to exceed that of a circle 34 inch in diameter in a potato 212 -inches in diameter or 6 ounces in weight.1
Light Brown Discoloration (Brown Center)Area affected not to exceed that of a circle 12 inch in diameter in a potato 212 inches in diameter or 6 ounces in weight.1Area affected not to exceed that of a circle 34 inch in diameter in a potato 212 inches in diameter or 6 ounces in weight.1
Occurring entirely within the vascular ring
Internal Brown Spot and Similar Discoloration (Heat Necrosis)Not more than the equivalent of 3 scattered spots 18 inch in diameter in a potato 212 -inches in diameter or 6 ounces in weight.1Not more than the equivalent of 6 scattered spots 18 inch in diameter in a potato 212 -inches in diameter or 6 ounces in weight.1

1Note: Correspondingly lesser or greater areas in smaller or larger potatoes.

[35 FR 18258, Dec. 1, 1970. Redesignated at 42 FR 32514, June 27, 1977, and further redesignated at 46 FR 63203, Dec. 31, 1981; amended at 56 FR 7553, Feb. 25, 1991; 56 FR 10302, Mar. 11, 1991; 73 FR 15058, Mar. 21, 2008 ; 73 FR 70586, Nov. 21, 2008; 76 FR 31789, June 2, 2011]

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Metric Conversion Table

§51.1566   Metric conversion table.

InchesMillimeters (mm)
18 equals3.2
14 equals6.4
12 equals12.7
34 equals19.1
1 equals25.4
112 equals38.1
2 equals50.8
212 equals63.5
3 equals76.2
312 equals88.9
4 equals101.6
412 equals114.3
OuncesGrams
1 equals28.35
4 equals113.40
5 equals141.75
6 equals170.10
7 equals198.45
8 equals226.80
9 equals255.15
10 equals283.50
12 equals340.20
14 equals396.90
16 equals453.60
18 equals510.30
19 equals538.60
20 equals567.00

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