Part 3 of this standard tabulates the size of allowable natural characteristics and manufacturing defects for each of the appearance classes listed in Part 1. It does not apply to overlaid panels.
Comparison: APA veneer grades referencing US PS 1-09 and EN 635-3 surface appearance grades
US PS 1-09
EN 635-3 (Softwood)
This is a simplified interpretation of the grading rules based on the appearance of the surface veneers. Equivalents cannot be exactly compared as two different sets of grading rules apply.