Provides guidance on levels of imperfections in electron and laser beam welded joints in aluminium and its alloys. 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 a) aluminium and its alloys b) all types of welds welded with or without additional filler wire and c) materials equal to or above 1 mm thickness for electron and laser beam welding.