What is the discharge duration of the H2O extinguisher?

• A. 30 to 45 seconds
• B. 10 seconds
• C. 60 seconds
• D. 2 minutes

Answer: (A)

The question is about how long an H2O extinguisher can discharge its contents in a continuous spray. The discharge duration is determined by how much water is in the canister and the rate at which it is expelled under pressure. For cabin-use water extinguishers, that combination typically yields a spray that lasts about 30 to 45 seconds. This 30–45 second window provides enough time to apply a steady stream over a small Class A fire while keeping the extinguisher light enough to handle. Shorter durations, like 10 seconds, wouldn’t give you sufficient time to control the fire, and much longer times (60 seconds or more) would imply a larger or differently configured unit than what is standard for on-board use.