Code of Federal Regulations Title 7. Agriculture § 7.51.2960 Damage

(a) Broken shells when the area from which a portion of the shell is missing is greater than the area of a circle one-fourth inch in diameter;  or when the two halves of the shell have become completely broken apart and separated from each other;

(b) Perforated shells when the area affected aggregates more than that of a circle one-fourth inch in diameter. The term “perforated shells” means imperfectly developed areas on the shell resembling abrasions and usually including small holes penetrating the shell wall;

(c) Adhering hulls when affecting more than 5 percent of the shell surface;

(d) Discoloration (or stain) which covers, in the aggregate, one-fifth or more of the surface of the shell of an individual nut, and which is brown, reddish brown, gray, or other color in pronounced contrast with the color of the rest of the shell or the majority of shells in the lot, or darker discoloration covering a smaller area if the appearance is equally objectionable;

(e) Mold when attached to the kernel and conspicuous;  or when inconspicuous white or gray mold affects an aggregate area larger than one square centimeter or one-eighth of the entire surface of the kernel, whichever is the lesser area;

(f) Shriveling when more than 5 percent of the surface of the kernel, including both halves, is severely shriveled, or a greater area is affected by lesser degrees of shriveling producing an equally objectionable appearance. Kernels which are thin in cross section but which are otherwise normally developed shall not be considered as damaged;  and,

(g) Insects when an insect or insect fragment, web or frass is present inside the shell, or the kernel shows distinct evidence of insect feeding.