No risk of fire or explosion in the petrol tank

I learnt that the fuel pump of my car is located within the tank itself, submerged in petrol. Could this be a fire risk?

In-tank electric fuel pumps are commonly used today. The pump pushes petrol from the tank, which is usually at the back of the car, to the engine compartment to be fed to the fuel injection system or a high-pressure pump. Unused fuel is then returned to the tank.

The reason there is no risk of fire or explosion in the tank is that petrol, by itself, will not combust. To catch fire, there must be a certain amount of oxygen and heat. Both are usually not in the fuel tank.

It used to be possible to flood the engine with fuel by continuously pumping the accelerator pedal. What happens then is that the engine simply refuses to start because the ratio of fuel to oxygen exceeds the required combustible mix.

In the absence of oxygen, there will be no explosion or fire even if you immerse a red-hot piece of steel in a bowl of petrol. Instead, the red-hot glow will be extinguished. Do not try this at home, though, since you cannot simulate an environment evacuated of oxygen.

Petrol fires occur only when there is a leak in the fuel line, usually in the engine compartment. The petrol could drip onto the hot exhaust system, where there is also ample ambient oxygen.

Incidentally, shooting a bullet into a fuel tank will not cause an explosion for the very reason stated above. That happens only in movies.