Galvanized steel is useful in industrial applications because it does not rust. Even though it does not rust, organic contaminants can find their way onto new galvanized steel and cause some residue to build up while in storage, exposed to humidity, or during shipping. Ideally, this storage stain would be cleaned off of your galvanized steel prior to delivery. If that is not the case, though, there are a few things you can do to remove storage stain while maintaining the integrity of the galvanized finish. Stain caused by organic contaminants and stain caused by humidity are both easily removed, but they are removed using different products. Here is a list of products and tactics for removing both organic stain and wet storage stain.
Organic Contaminants. To clean organic contaminants off of galvanized steel you can use cleaners such as Comet, bleach, Goof Off, Simple Green, The Must for Rust, or stainless steel cleaner. Apply these products to the galvanized steel and rinse off according to the manufacturer’s instructions, then dry the galvanized steel. All of these products have been tested on galvanized steel to ensure that they will not do any damage to the coating or its appearance, but you should still test it in a small area just to make sure it does not damage the coating on your particular piece of steel.
Wet Storage Stain. First of all, you should try to prevent wet storage stain by providing air flow to the galvanized surfaces and removing any standing water from the surface of the galvanized steel. If water storage stain cannot be avoided, though, a number of cleaners will remove it. Start by thoroughly drying the surface of the galvanized steel. Then you can apply CLR, lime juice, Naval Jelly Rust Dissolver, Picklex 10G, or white vinegar. After applying, scrub the cleaner, rinse away, and thoroughly dry the galvanized steel.