1. The problem statement, all variables and given/known data A galvanized steel roof shows small brown stains indicating minor rust. There are no penetrations of the material. What would be the most appropriate treatment and why? 2. Relevant equations N/A 3. The attempt at a solution The brown stains indicate that the zinc has been corroded somehow or there were un-galvanised patches to begin with, thus exposing the iron interior to oxidation. However, I am unsure of what method would be best to treat this. Any help would be appreciated, thank you.