Your fuel tank won’t explode if you fill it during a heatwave

15 July 2021
What was claimed

Filling up your car in hot weather could cause the fuel tank to explode.

Our verdict

Fuel systems in cars are designed to cope with summer heat. The auto-combustion point of fuel is much, much higher than a car’s fuel tank could feasibly reach.

A post on Facebook, shared more than half a million times, warns that filling a fuel tank in hot weather could cause the tank to explode. 

“Due to [an] increase in temperature in the coming days, please don’t fill petrol to the maximum limit. It may cause [an] explosion in the fuel tank. Please fill the tank about half and allow space for air.” 

This is not true, and has already been debunked a number of times online. 

In 2018, a spokesperson for motoring organisation RAC, Rod Dennis, said: “All fuel systems on passenger vehicles are designed to cope with any expansion of fuel, or vapour coming from the fuel.

“There is no risk of explosion from filling up a fuel tank fully and drivers should have no concerns in doing so.”

In their fact check of a similar post, fact checking service Snopes write: “The temperature at which fuel auto-ignites (i.e. the temperature at which fuel will combust without a trigger or spark) is around 495ºF [257C]. 

“This level is far higher than any temperature a covered, insulated tank could possibly achieve simply by being driven or parked on planet Earth.”

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