One of the most widespread myths is the danger of using mobile phones at the petrol station. What does science have to say about the real risk of explosions or fires caused by their use?
One of the things that we should do, but often forget to do, is turn off our mobile phones when we are at a petrol station. This is what article 115 of the General Traffic Regulations says, which literally prohibits “keeping the engine, lights, as well as electrical systems such as the radio or devices that emit electromagnetic radiation turned on”.
According to Traffic regulations, the latter case would apply to mobile phones. At this point, we all know that these devices are low-power radio-frequency transmitters (between 450 and 2700 MHz), with a peak power value that ranges between 0.1 and 2 watts. Can they really have an impact in a petrol station?
As explained in Naukas, the two greatest dangers related to the use of mobile phones are the possibility of explosion or fire. Could something like that happen if you keep your phone turned on at the petrol station?
Science says “no” because these devices emit very little energy (less than 1 W/cm2).
The myth was also debunked by the Mythbusters a few years back. The episode saw Adam Savage and Jamie Hyneman try to make a mobile phone explode in a chamber full of petrol vapour, and failed. See video below.
The team concluded that a properly-working cell phone poses almost no danger of igniting gasoline, even when surrounded by gasoline vapour with the optimum fuel-air mix for ignition.
The actual risk comes from an electrostatic discharge from a charged driver, often a result of continually getting in and out of the vehicle (without discharging).
If cell phones don’t cause fires, then why do petrol stations put up signages that show they do?
The only way that a mobile phone could generate a spark at a petrol station would be due to a defective battery, which is unlikely and could also occur in the case of the car’s own battery. While the possibility is remote, there is a low risk that an explosion could occur from the gases that are emitted by the hose and not from the fuel.
The truth is that the use of mobile phones is probably more dangerous as a source of distraction than as the possible source of an explosion. According to a report from the Petroleum Equipment Institute, there are no documented incidents at petrol stations related to fires or explosions caused by the use of mobile phones.
In short, the scientific evidence does not support the hypothesis that these devices cause serious accidents. However, you should remember that using mobiles at petrol stations can also result in people being run over, carelessness with the car and other pedestrians, etc. For this reason, using mobile phones at the petrol station is not recommended.