Question 796 Deck Safety

The correct answer is C) Classes A & B. Foam fire extinguishers are effective on Class A (ordinary combustible) and Class B (flammable liquid) fires, but not on Class C (energized electrical) fires. This is because the foam works by creating a blanket over the burning material, smothering the fire and preventing the release of flammable vapors. However, foam is not an effective conductor of electricity, so it should not be used on energized electrical equipment. The other answer choices are incorrect because Class B & C (A) does not include Class A fires, and All of the above (D) is incorrect since foam extinguishers are not effective on Class C fires.