In marine piping systems, which components are required to be protected inside and out against corrosion?

• A. Wooden supports
• B. Aluminum components
• C. Ferrous piping, valves, and fittings
• D. Plastic piping

Answer: (C)

Ferrous piping, valves, and fittings are the parts most at risk in a marine setting because iron and steel readily corrode in saltwater and damp air. Protecting these components on both the inside surfaces (the bore that contacts seawater or condensate) and the outside surfaces (the exposed exterior) helps prevent corrosion from advancing from either side. Internal protection stops corrosion from seawater chemistry inside the pipe, while external protection shields against atmospheric and splash exposure that can undermine coatings and metal more broadly. This dual protection preserves strength, prevents leaks, and extends the life of the system. Wooden supports, aluminum components, and plastic piping have different corrosion considerations, and the requirement to protect both sides specifically targets ferrous components due to their higher susceptibility in marine environments.