7 CFR 810.604: Grades and grade requirements for flaxseed.

Grade Minimum test weight per bushel (pounds) Maximum limits of damaged kernels—

Heat damaged kernels (percent) Total (percent)

U.S. No. 1 49.0 0.2 10.0

U.S. No. 2 47.0 0.5 15.0

U.S. Sample grade—

U.S. Sample grade is flaxseed that:

(a) Does not meet the requirements for the grades U.S. Nos. 1 or 2; or

(b) Contains 8 or more stones which have an aggregate weight in excess of 0.2 percent of the sample weight, 2 or more pieces of glass, 3 or more crotalaria seeds (Crotalaria spp.), 2 or more castor beans (Ricinus communis L.), 4 or more particles of an unknown foreign substance(s) or a commonly recognized harmful or toxic substance(s), 10 or more rodent pellets, bird dropping, or equivalent quantity of other animal filth per 11⁄8 to 11⁄4 quarts of flaxseed; or

(c) Has musty, sour, or commercially objectionable foreign odor (except smut or garlic odor), or

(d) Is heating or otherwise of distinctly low quality.