51.1576—U.S. Grade B Small; U.S. Grade B Medium; U.S. Grade B Medium to Large; U.S. Grade B Large.
               		
               	 	
               	 	
               	 	               	 	               	 	               	 	               	 	
               	 	
    
         Potatoes of each of these grades shall meet the requirements for U.S. Grade A Small; U.S. Grade A Medium; U.S. Grade A Medium to Large; and U.S. Grade A Large, except for the increased tolerance for defects specified below. (See  § 51.1577.)
     
    
        
        (a) Tolerances.
         Incident to proper grading and handling, except for the tolerance for size, not more than a total of 20 percent, by weight, of the potaotes in any lot may fail to meet the requirements of the grade, but not more than 5 percent shall be allowed for potatoes which are seriously damaged by any cause, including not more than 1 percent for potatoes affected by soft rot or wet breakdown. (See  § 51.1579.)