Europan oak floors timber grades

                                                    European Oak Grade Standard                        (  by  Yorking Hardwood)
Dead Kont 10mm,Maximum 3,drop or crack not allowed diameter50mm,when 20mm,To be filled fully with smoked oak knot branch,repair with putty,Putty area 20mm daimeter 100mm, big konts,no more than 30% of the totol amount.
Living Kont 20,Maximum3 allowed allowed 
Sapwood  10% of the panel width, to be colored same as surrounding area, no more than 10% of the totol amount , decentralized packed 30% of the panel width,to be colored same as surrouding area, no more than 45% of the totol amount ,full-length and both sides sapwood not allowed , decentralized packed full length sapwood not allowed
Color variation slightly allowed ,unnatural not allowed allowed ,but obvious color varitaion not allowed  allowed ,but abvious color varitation not allowed 
Black line 80*2MM ,Maximum 1 allowed allowed
Stain  extremely slighty allowed  slighty allowed  slighty allowed