Which foam is most well suited for gasoline spills?

Which foam is most well suited for gasoline spills?

• A. Class A Foam
• B. Aqueous Film Forming Foam (AFFF)
• C. Protein Foam
• D. Fluoroprotein Foam

Answer: (B)

For gasoline spills, you want a foam that quickly blankets the surface and suppresses vapors while cooling the fuel. Aqueous Film Forming Foam does this by forming a thin, water-based film on top of the hydrocarbon. The film spreads rapidly across the spill, creates a barrier between the fuel and air, and helps knock down the fire and control vapors, making it the most effective choice for gasoline spills.

Class A foam is designed for ordinary combustibles like wood and paper, so it doesn’t provide the same surface film or vapor suppression on hydrocarbon fuels. Protein foam forms a good blanket but can drain and degrade with light fuels like gasoline, reducing effectiveness. Fluoroprotein foam is capable but tends to be more expensive and not as reliable for rapid knockdown on gasoline spills as AFFF’s film-forming action.