What is the purpose of a water break test?

• A. To make certain that the bare metal surface is thoroughly clean
• B. To determine coating thickness
• C. To assess corrosion resistance of paint
• D. To locate pinhole leaks

Answer: (A)

The water break test checks how clean the metal surface is before applying coating by seeing how water wets it. When the surface is free of oils, greases, and other contaminants, water spreads evenly in a smooth film. If residues remain, water beads up or breaks into droplets, signaling that cleaning is still needed. This ensures proper adhesion of the primer and coating. It isn’t used to measure coating thickness, evaluate the paint’s corrosion resistance, or locate leaks.