This standard gives quidance on levels of imperfections in electron and laser beam welded joints in steel. Three levels are given in such a way as to permit application for a wide range of welded fabrications. The levels refer to production quality and not to the fitness-for-purpose of the product manufactured. This standard applies to electron and laser beam welding of: - unalloyed and alloyed steels; - all types of welds welded with or without additional filler wire; - materials equal to or above 0,5 mm thickness.