Guidelines for the Care & Cleaning of Stainless Steels
316 stainless steel will not stain if maintained in clean conditions. It is protected by a thin, passive layer of chromium-oxide which is established naturally by exposure to air.
Any staining which occurs can usually be attributed to impurities deposited on the surface of the stainless steel or certain atmospheric pollutants.
A common cause of this phenomenon on building construction sites is the ferrous particles from angle grinding, drilling and wire brushing of other materials.
Should this occur the ferrous particles must be removed from the surface of the stainless steel using warm water and a household detergent. If the staining has been left for some time a special stainless steel cleaner may be necessary.
DO NOT use a wire brush or wire-wool scourer.
DO NOT use an acid based solvent or cleaner.
After removal of the staining, the surface must be left dry and clean to allow the protective passive chromium-oxide layer to re-form. DO NOT apply a light coat of oil as this will prevent oxygen from getting to the material.