All malleable iron water fittings must be?

Malleable iron water fittings must be galvanized to provide a protective layer against corrosion and rust, which are common issues when metal components are exposed to moisture. Galvanization involves coating the malleable iron with a layer of zinc, which reacts with environmental elements to prevent corrosion and extends the lifespan of the fittings. This is particularly important in plumbing applications where fittings regularly come into contact with water, as the presence of moisture can lead to significant deterioration over time if adequate protection is not provided. Galvanized fittings are widely used in various plumbing systems due to their durability and resistance to environmental wear.