Minimum dimensions of the pieces.	Clear cuttings	Yield	Sound sapwood	Heart	Wane	Shakes	Knots and holes	Deformations
FAS - First And Second	Width of 6 " and wider - length of 8 ' and longer	4 " x 5 ' or 3 " x 7 '	83 1/3 % (10/12ths) to 100% clear-wood cuttings over the entire surface of the board	Tolerated without limits	Tolerated outside cross cut if the length in inches is smaller than the surface measured.	Must not exceed 1/2 of the width of the piece on each edge. Tolerated if the size does not exceed 1/2 of the surface measured	The cumulated length must be smaller than 2 times the surface measured. Not considered if not exceeding 1 inch on each extremity.	The diameter of each knot or hole must be < 1/3 of the surface measured	Tolerated if made straight again during process
FAS One Face - F1F	The better face must meet all FAS requirements while the poor face must meet all the requirements of the Number 1 Common grade
SELECTS	Width of 4 " and larger - length of 6 ' and longer	This grade is virtually the same as F1F except for the minimum board size required
No 1 COMMON	Width of 3 " and larger - length of 4 ' and longer	4 " x 2 ' or 3 " x 3 '	from 66 2/3 % ( 8/12ths) up to 83 1/3 %	Tolerated without limits	< 1/2 of the length	Without limits	Without limits
No 2 COMMON	Width of 3 " and larger - length of 4 ' and longer	3 " x 2 '	from 50% ( 6/12ths) up to 66 2/3 %.	Without limits	Without limits	Without limits	Without limits

National Hardwood Lumber Association (NHLA - http://www.natlhardwood.org/)