(1) The official red tag shall be used to designate seed lots that are the equivalent of U.S. No. 2 grade with the following exceptions:

(a) size -- the minimum size shall be 1 1/2 ounces and the maximum shall be 12 ounces.

(b) growth cracks shall not be scored.

(c) surface or russet scab shall not be scored.

(d) cuts and bruises shall be scored when removal causes loss of more than 15% of the total weight of a tuber.

(e) second growth shall not be deliberately removed.

(f) the following blue tag exceptions shall also apply to red tags: air cracks, sunburn (greening), stem-end discoloration, immaturity, sprouts, oversize, undersize, hollow heart, hollow heart with discoloration, light brown discoloration, brown center, freezing injury, and the tolerance for late blight tuber rot, soft rot or wet breakdown.