Question 845 Deck Safety

The correct answer is A) breaking the chain reaction. Dry chemical extinguishers work by interrupting the chemical chain reaction that occurs during a fire. The dry chemical agent, such as sodium bicarbonate or potassium bicarbonate, acts to break this chain reaction, thereby suppressing the fire. This is the most effective extinguishing action of dry chemical extinguishers. The other options are incorrect because they do not accurately describe the primary mechanism by which dry chemical extinguishers work. B) the CO2 that is formed by heat is not the primary extinguishing action. C) smothering is the mechanism for carbon dioxide (CO2) extinguishers, not dry chemical. D) shielding of radiant heat is not the main extinguishing action of dry chemical agents.