6. Runtime errors

— In a marine environment, tubular structures in patinable steel supporting conveyor belts have had to be protected by painting in the same way as ordinary steel, but their performance is better.

— Skateable steels had been used to make metal troughs for a low-slope roof. Puddles of water created areas of permanent humidity where the protective oxide film was unable to form. Corrosion perforated the sheets, which had to be completely replaced.