Which type of extinguishing agent is most effective for aviation fuel fires?

• A. Water
• B. Diatomaceous earth
• C. Foam
• D. Carbon dioxide

Answer: (C)

Foam is considered the most effective extinguishing agent for aviation fuel fires due to its unique properties that address the challenges posed by such flammable liquids. Aviation fuels, like Jet A, are lighter than water and can float on its surface, while their high flammability makes them especially hazardous.

Foam works by creating a blanket over the fuel, sealing off the oxygen and preventing vapors from igniting. It also cools the surface of the burning fuel, which helps suppress the fire. This dual action of smothering the fire and cooling the heat is critical in extinguishing aviation fuel fires effectively and prevents rekindling.

Other agents have limitations in this specific context. Water, for instance, may not only be ineffective but can exacerbate the situation, as it can spread the fire if the fuel floats on top. Diatomaceous earth lacks the ability to smother the fire effectively and is more useful for other types of substances. Carbon dioxide can displace oxygen but often does not cool the fire sufficiently and may not be effective against larger fires, particularly those fueled by aviation fuels. Therefore, foam remains the preferred choice for its comprehensive fire suppression capabilities.