Why do you have to turn engine off while getting gas?

You must turn off your engine while getting gas to reduce the risk of igniting gasoline vapors. An idling engine can produce sparks or heat, which, in the presence of flammable vapors, could lead to a fire or explosion. Additionally, many gas stations have safety regulations that require engines to be off during refueling for this reason. It's a precautionary measure to ensure the safety of both the customer and the facility.