The term encrustation refers to which phenomenon?

• A. Scale buildup on interior surfaces
• B. Corrosion
• C. Air leakage causing contamination
• D. Sedimentation

Answer: (A)

Encrustation is the buildup of mineral scale on interior surfaces. It happens when minerals dissolved in water precipitate and cling to the inside of pipes, valves, and pump components, forming a crusty layer. This scale narrows channels, increases friction losses, and can impair equipment performance. It’s different from corrosion, which is the chemical deterioration of metal; it’s also not caused by air leaks or by solids simply settling out of suspension, which are separate issues. So the term specifically describes mineral deposits that form and adhere to interior surfaces.