Pitted Rust is defined as which of the following?

• A. Rust that cannot be removed with a soft cloth
• B. Distended ends of the can
• C. Flat sides on the container
• D. A dent on the surface of the can

Answer: (A)

Pitted rust means corrosion that has penetrated the metal surface, forming tiny pits that cannot be wiped away with a soft cloth. This depth of corrosion indicates the can has been damaged at the metal level, compromising its integrity and the protective barrier for the contents. Superficial rust that you can wipe off isn’t as serious because it hasn’t attacked the metal to the same extent. The other options describe different can defects—distended ends indicate internal gas pressure, flat sides describe a form of deformation, and a dent is mechanical damage—none of which define pitted rust.