(a) Damaged kernels. Kernels and pieces of grain kernels for which standards have been established under the Act, that are badly ground-damaged, badly weather-damaged, diseased, frost-damaged, germ-damaged, heat-damaged, insect-bored, mold-damaged, sprout-damaged, or otherwise materially damaged.

(b) Foreign material and fines. All matter other than whole flaxseed that passes through a 5⁄64 triangular-hole sieve, and all matter other than grains for which standards have been established under the Act, that remains in the sieved sample.

(c) Grades. U.S. Mixed Grain, or U.S. Sample grade Mixed Grain, and special grades.

(d) Heat-damaged kernels. Kernels and pieces of grain kernels for which standards have been established under the Act, that are materially discolored and damaged by heat.

(e) Sieve— 5⁄64 triangular-hole sieve. A metal sieve 0.032 inch thick with equilateral triangular perforations the inscribed circles of which are 0.0781 ( 5⁄64 ) inch in diameter.