Which statement is true regarding the use of galvanized pipe for foam concentrate piping?

• A. It is allowed under the policy.
• B. It is prohibited.
• C. Only in outdoor installations.
• D. Only if coated.

Answer: (B)

Foam concentrate piping must be made from materials that won’t interact with or contaminate the foam. Galvanized pipe has a zinc coating that can be attacked by many foam concentrates, leading to coating degradation, zinc leaching into the foam, and corrosion of the pipe. This can cause leaks, clogged nozzles, and degraded foam performance, compromising the system’s effectiveness. Because of these compatibility and contamination risks, galvanized piping is not allowed for foam concentrate lines. The other options don’t fix the fundamental issue: coating or outdoor use doesn’t address the chemical incompatibility, so they’re not acceptable.