Deck General · Extinguishing Agents
Why should a straight water stream NEVER be applied to a Class B (flammable liquid) fire?
- AWater reacts chemically with flammable liquids to create toxic gases
- BThe stream can spread burning liquid and intensify the fire✓ Correct
- CWater is heavier than fuel and will sink beneath the flame, having no effect
- DWater removes the oxygen layer that was naturally smothering the fire
Explanation
A high-velocity water stream striking a pool of burning liquid will splash and scatter the fuel, spreading the fire over a wider area and potentially splattering burning material onto personnel. Water fog at low velocity can be used on some Class B fires to cool and smother, but a solid stream is prohibited. Foam, CO2, or dry chemical are preferred agents.
Authority: Firefighting (USCG deck topic)
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