Grades and grade requirements for corn.

Grade Minimum test weight per bushel (pounds) Maximum limits of Damaged kernels Broken corn and foreign material (percent) Heat damaged kernels (percent) Total (percent) U.S. No. 1 56.0 0.1 3.0 2.0 U.S. No. 2 54.0 0.2 5.0 3.0 U.S. No. 3 52.0 0.5 7.0 4.0 U.S. No. 4 49.0 1.0 10.0 5.0 U.S. No. 5 46.0 3.0 15.0 7.0 U.S. Sample Grade U.S. Sample grade is corn that: (a) Does not meet the requirements for the grades U.S. Nos. 1, 2, 3, 4, or 5; or (b) Contains stones with an aggregate weight in excess of 0.1 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), 8 or more cockleburs (Xanthium spp.), or similar seeds singly or in combination, or animal filth in excess of 0.20 percent in 1,000 grams; or (c) Has a musty, sour, or commercially objectionable foreign odor; or (d) Is heating or otherwise of distinctly low quality. [60 FR 61196, Nov. 29, 1995]