ISO 2428:1974

Plywood — Veneer plywood with rotary cut veneer for general use — Classification by appearance of panels with outer veneers of birch

Classifies the surfaces in one of the grades E, I, II, III, and IV in accordance with ISO 2426 as defined by the permissible defects indicated in the table. The terms used are defined in ISO 2074. A list of the different species of birch used for this purpose is given in the Annex.