Which option best describes the action to stop deterioration on a CAT 4 item?

• A. Surface prep and touch up
• B. Replace component
• C. Investigate cause only
• D. Seal area without prep

Answer: (A)

Stopping deterioration means removing the active corrosion and restoring the protective barrier so the metal isn’t exposed to moisture or chemicals anymore. Surface prep removes rust, scale, and contaminants and creates a clean, rough surface for a coating to adhere. A touch-up then re-applies the protective coating, sealing the area and preventing renewed exposure. This combination directly halts the progression of corrosion by restoring the protective finish.

Sealing the area without prep leaves the corrosion products and bare metal underneath, which can trap moisture and worsen deterioration. Investigating the cause alone doesn’t stop ongoing damage. Replacing the component might be needed in severe cases, but for stopping deterioration on this item, surface prep plus touch-up is the appropriate immediate action.