If you search the internet you will find scholarly article on stainless steel and rust, many getting into discussions down to the molecular level. While all of these are true they are not practical when dealing with rust or rust like stains in a stainless steel sink.
Below is a link to an article from a plumbing supply house on the topic. The key points in the article are:
- “Type 304 (stainless steel,) or any other type employed in the manufacture of sinks will not stain, but it will corrode when it comes in contact with certain chemicals.”
- “One substance that can cause rust-like eruptions if left in contact for an extended period of time is Triclosan. Triclosan is an organic chemical made up of three chlorine molecules that is used in most anti-bacterial soaps, such as Dial.”
- “The best news is that once these rust-like eruptions occur, they are easily removed with a maroon Scotch-Brite pad and a cleanser such as Barkeeper’s Friend or Bon Ami, available at most large grocery or home improvement stores.”
John Oldach, Buffalo Plumbing Showroom’s representative for Elkay sinks, has a favorite phone call that he regularly receives. It starts out,”My Elkay sink is rusting.
Source: Can Stainless Steel Rust? Expert Advice on Avoiding Stainless Steel Sink Problems | Buffalo Plumbing Showroom