What shall be done to vehicle engines before fueling (all internal combustion engines except diesel)?

What shall be done to vehicle engines before fueling (all internal combustion engines except diesel)?

• A. The engine must be shut off
• B. Keep running at idle
• C. Disconnect the battery
• D. Open the fuel cap

Answer: (A)

Shut off the engine before fueling to remove ignition sources and minimize the risk of fire or explosion from gasoline vapors. When a gasoline engine runs, the electrical system can produce sparks and heat from the exhaust, both of which can ignite fuel vapors. Turning the engine off stops those ignition sources, making fueling safer. Keeping the engine at idle would keep those hazards present, and disconnecting the battery is unnecessary and could create other dangers. Opening the fuel cap isn’t required for safety and can let vapors escape or spill. So shutting the engine off is the safest, standard practice.

Shut off the engine before fueling to remove ignition sources and minimize the risk of fire or explosion from gasoline vapors. When a gasoline engine runs, the electrical system can produce sparks and heat from the exhaust, both of which can ignite fuel vapors. Turning the engine off stops those ignition sources, making fueling safer. Keeping the engine at idle would keep those hazards present, and disconnecting the battery is unnecessary and could create other dangers. Opening the fuel cap isn’t required for safety and can let vapors escape or spill. So shutting the engine off is the safest, standard practice.