When refueling a hazmat-loaded vehicle:
Correct. Engine off, no smoking within 25 feet of the vehicle being fueled, and someone must be in control of the fueling at the nozzle.
CDL Practice Question #238
Category: Hazmat
Why this question matters
This question is one of 68 in our Hazmat bank. The reasoning above comes directly from the AAMVA CDL Manual, the source document used by every U.S. state DMV. Memorizing the underlying rule — not just the letter answer — is what separates passing on the first attempt from a return trip and another fee.