In addition to the quality requirements specified for the above grades, potatoes shall also meet the requirements for minimum and maximum diameter or weight, and the tolerances as specified for the various grades in the table appearing in this section. Potatoes specified as meeting one of the grades may be of any size within its size range requirements, except that it is not permissible to specify a lot as “U.S. Grade A Medium to Large,” or “U.S. Grade B Medium to Large,” unless more than 15 percent, by weight, of the potatoes are larger than the maxiumum size required for U.S. Grade A Medium, or U.S. Grade B Medium, respectively. For example, a lot of round or intermediate-shaped potatoes to be specified as “U.S. Grade A Medium to Large” must have more than 15 percent, by weight, of potatoes from 3 to 4 inches in diameter.
| Grades | Size range requirements, round or intermediate shaped varieties | Size range requirements, long varieties | Tolerance for size | |||
|---|---|---|---|---|---|---|
| Minimum diameter (Inches) | Maximum diameter (Inches) | Minimum diam. or wt. | Maximum weight (Ounces) | Under-size (Percent) | Over-size (Percent) | |
| U.S. Grades A & B small | 11⁄2 | 21⁄4 | 11⁄2 inches | 4 | 3 | 15 |
| U.S. Grades A & B medium | 21⁄4 | 3 | 4 ounces | 10 | 5 | 15 |
| U.S. Grades A & B medium to large | 21⁄4 | 4 | 4 ounces | 16 | 5 | 15 |
| U.S. Grades A & B large | 3 | 4 | 10 ounces | 16 | 5 | 15 |