Question 849 Deck Safety

The correct answer is B) The dry chemical powder attacks the fuel and oxygen chain reaction. Dry chemical fire extinguishers work by interrupting the chemical reaction that sustains the fire. The dry chemical powder, usually sodium bicarbonate or potassium bicarbonate, interferes with the chain reaction between the fuel and oxygen that feeds the fire. This disrupts the fire's ability to continue burning, effectively extinguishing it. The other options are incorrect because they do not accurately describe the primary mechanism by which dry chemical fire extinguishers work. Option A is incorrect because the powder does not form a solid coating. Option C is incorrect because the dry chemical does not simply smother the fire. Option D is incorrect because the stream of dry chemical does not primarily cool the fire.