The operating motor on one of your ship's watertight doors needs to be replaced. What minimum short-time rating should the replacement motor have in hours?

Correct Answer: Option A — 1/12

Per 46 CFR 111.97, watertight door motors must be rated for the specific demands of emergency operation. A short-time rating of 1/12 hour (5 minutes) is the minimum standard for these motors, as they are intended for intermittent, short-duration operation to close doors during an emergency, rather than continuous duty.