What effect can a dirty or damaged backfire flame arrestor have on fire risk?

• A. It improves flame arrestor function when dirty.
• B. It reduces fuel emission and increases engine power.
• C. It has no effect on fire risk.
• D. It may not function properly and permit flammable vapors to ignite.

Answer: (D)

A backfire flame arrestor must stay clean and intact to do its job of cooling and quenching any flames that try to travel back toward the fuel system. When it’s dirty or damaged, those small passages can be blocked or cracked, so it can’t stop a flame from propagating or from igniting vapors. That’s why it may not function properly and permit flammable vapors to ignite, increasing the fire risk. Keep it clean and replace it if damaged to maintain its protective function.