Chlorine can cause stainless steel to rust, but it is not the primary cause of rust on stainless steel. Stainless steel contains chromium, which forms a protective layer of chromium oxide on the surface of the metal that prevents further corrosion. However, chlorine can break down this protective layer, leading to corrosion and the formation of rust. This is why stainless steel can rust when exposed to high levels of chlorine, such as in swimming pools or saltwater environments.

To prevent rust on stainless steel, it is essential to take measures to protect it from chlorine. This may include limiting exposure to chlorine, regularly cleaning and drying the surface of the metal, and applying a protective coating to the steel.