When fueling a placarded vehicle, someone must always be:

• A. At the nozzle, controlling the fuel flow
• B. In the cab with the engine off
• C. Outside the vehicle
• D. At the fuel cap only

Answer: (A)

Placarded hazmat fueling requires an attendant at the nozzle controlling the fuel flow. This position puts you in immediate contact with the fueling operation, so you can stop the flow right away if a spill, leak, or dangerous vapor is detected or if a fire starts. Being at the nozzle also helps prevent static ignition risks by keeping the flow under direct control and ensuring constant supervision of the fueling process.

Standing in the cab or simply staying near the cap does not provide the same level of control or rapid response, and would delay shutting off fuel in an emergency. Keeping the engine off and avoiding ignition sources are important safety steps, but the critical requirement here is having someone actively managing the flow at the nozzle.