Recently, I noticed the fine-print warning at the petrol station about the risk of fire from static electricity sparks. Is this for real?
You’re probably more likely to be struck by lightning, but in certain circumstances, the static electricity you carry out of your car can ignite gasoline vapours at the pump.
When you exit the car, first of all, you’re going to open your door, and when you touch the door you’re no longer charged. Then you’re probably going to touch the nozzle to get it out of the boot. You may use a credit card, you’re going to touch that, too. Usually, there’s a door on your car that gets you to the fill cap, and you’re going to touch the cap.
So you have seven or eight times when you’ll dissipate your static electricity – and all it takes is once. So we never have a problem when we initially fuel.
So, what is the real risk?
The real risk is when you re-enter your vehicle after the fuelling process has begun.
You might be sitting in the car and then pivoting 90 degrees to the left and popping out without touching something. So when fuelling is going on, you’re in your car, you move around – you’re checking on your child, checking the odometer reading, or returning your credit card to a purse.
So while you are in the car, you move around, produce friction and generate static. After a while, you pop out again, haven’t dissipated the static charge, and then you touch their nozzle.
As gasoline goes in, the gas vapours come out of the filling pipe, so you have a source of ignition when the static discharges from your hand to the nozzle – exactly where the vapours are coming out of the filling pipe, and this is likely to cause a fire in the petrol station.
An eye-opening example of this can be seen in the video footage from a gas station surveillance camera below.
Always Discharge Your Static Electricity
Aim to discharge any static before you reach for the pump nozzle. You can do this by touching the metal parts of your vehicle. Static electricity is produced by friction, and it can cause sparks.
“A static electric charge can develop on your body as you slide across the seat, and when you reach for the pump, a spark can ignite [petrol] vapour,” cautions the National Fire Protection Association.
“If you must get into the vehicle during refuelling, discharge any static electricity by touching metal on the outside of the vehicle, away from the filling point, before removing the nozzle from your vehicle,” they advise.
In case it happens
Again, it’s extremely rare, but if a fire does occur while refuelling, resist the temptation to remove the nozzle from your vehicle. Rather, step away and the attendant will shut off the pumps using emergency controls.
The lesson for today: Next time, when you are at the petrol station, make sure you discharge your static before fueling up your tank.