On liquid fuel fires, Class B foam is used primarily to achieve which effect?

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Multiple Choice

On liquid fuel fires, Class B foam is used primarily to achieve which effect?

When fighting liquid fuel fires, Class B foam is used to blanket the surface and form a barrier between the fuel and the air. This creates an air-excluding layer that limits oxygen reach and suppresses fuel vapors, effectively smothering the flame. The foam’s water content also provides cooling, which aids in reducing heat and slowing vaporization, but the primary extinguishing action is the smothering effect from the foam blanket.

When fighting liquid fuel fires, Class B foam is used to blanket the surface and form a barrier between the fuel and the air. This creates an air-excluding layer that limits oxygen reach and suppresses fuel vapors, effectively smothering the flame. The foam’s water content also provides cooling, which aids in reducing heat and slowing vaporization, but the primary extinguishing action is the smothering effect from the foam blanket.

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