Much like the eternal question of Shouldst Thou Warm Yon Car Up In The Winter?, it seems like the question of Do I Really Have To Turn Off My Car When I Fill It Up? is capable of generating more intense responses than one would expect. Also, those signs at the gas station that ask you not to use your cellphone — what’s up with those?
So, with this in mind, let’s dive into these questions: Do you, in fact, really have to turn off your car when refueling, like the sign at the gas station says? And not use your phone? Come on!
Let’s start with keeping your car running while refueling. I was reminded that this question was A Thing when I saw this tweet about someone who really, really loves Camrys:
You’ll notice that before the conversation was derailed by that glorious loon who owns at least five Camrys, that same quintuple-Camryist also stated, with some defiance, that he leaves his cars running while filling with gas. And, remember, all of this started because someone called out a Camry owner refilling their car with it running as well.
Gas stations pretty clearly ask patrons to shut off their cars while filling up. But why? Is there a real danger in filling up your tank while the engine is running? Conceptually, there shouldn’t be, and we’ve all seen racecars filling up while running.
With that in mind, I reached out to our pal Bozi Tatarevic, biscuit fetishist and race team pit crew member, to ask what he thought of all this.
Keep in mind that racing pit crews have someone standing ready with a fire extinguisher during refueling stops (this goes for most amateur racing, like 24 Hours of Lemons, too) so there’s clearly some risk. Here’s what Bozi said:
“The biggest risk on racecars is fuel falling on something hot like the brakes or an exhaust component, but we also have someone with an extinguisher standing by when fueling. Not sure that there is a huge risk just from the engine itself turning.”
Bozi also told me that he’s seen a fire start from a fuel jug that failed and spilled onto a hot turbocharger, and he thought that the main issues from a street car could be sparks from an electrical component.
There’s nothing technically dangerous about filling up your car while it’s running. Your pressurized fuel system may throw a P0457 code because you’re running with the fuel cap off, but that’s about the extent of the trouble, really.
That said, from the gas station’s perspective, they know nothing about the condition of your car. They don’t know if you have foglamps with exposed wires that the insulation has worn off of, or if you have some big aftermarket exhaust system that sticks way out beyond your bodywork, or any number of other hot, sparky things that could come into contact with a few drops of fuel and go up like a Viking funeral.
If the car is off, at least there’s no current running through any wires, and hot components have a chance to cool down. If you own a gas station, your goal is to try and minimize any possibility of a fire, no matter how remote or unlikely—remember, you’re parked right on top of huge tanks of gasoline. Why risk it?
There’s also something just unsatisfying about needlessly burning fuel at the same time you’re putting fuel in. Why do it? What are you proving?
I get there are conditions where leaving the car running makes sense — you don’t think you’d be able to start the car again (I’ve been there), or even if it’s absurdly cold out and you have kids or pets in the car you want to keep warm. I think those situations could be reasonable exceptions.
But otherwise, if you’re just doing it to prove to the world that you don’t play by anyone’s rules or whatever, grow up. Yes, technically, you can refill your car while it’s on and likely be fine, but in doing so you absolutely are introducing many new possibilities for fire, so just shut off your damn car.
OK, now for — in my opinion — the stranger requirement: no cellphone use while pumping gas.
Unless you’re still using one of those old Nokia Sparksabunch 2100 coal-powered flip phones from the early 1990s, is this something you really need to worry about?
Honestly? No. And I’m not just saying that because I’ve never, ever seen a cellphone or any other similar device emit a spark, I’m saying it because the Petroleum Equipment Institute (PEI), which calls itself the “leading authority for fuel and fuel handling equipment” says so.
In fact, here’s what they say:
We have not documented a single incident that was caused by a cellular telephone.
Cellphones continue to be cited as causing fires at the pump in e-mails circulating on the Internet. So far, we have been unable to document any incidents that were sparked by a cellular telephone. In fact, many researchers have tried to ignite fuel vapors with a cell phone and failed.
Also, the FCC has said similar things exonerating cellphones as gas-station arsonists:
The Federal Communications Commission has been alerted to reports and rumors that suggest it is dangerous to use a wireless phone while filling your vehicle with gas or in the presence of flammable materials. The rumors and reports may be fueled by warnings posted at gas stations or included in wireless phone owners’ manuals suggesting that wireless phones should not be used around fuel vapors.
There Is No Evidence That These Reports Are True
One of the rumors circulating describes incidents where consumers are injured by fires or explosions when they use their cell phones at gas stations. In these stories, a fire was reportedly ignited or an explosion occurred when an individual answered a ringing cell phone. Supposedly, an electrical spark from the phone ignited a fire or caused an explosion.
The wireless industry has done studies on the potential for wireless phones to create sparks that could possibly ignite flammable materials. The studies generally conclude that while it may be theoretically possible for a spark from a cell phone battery to ignite gas vapor under very precise conditions, there is no documented incident where the use of a wireless phone was found to cause a fire or explosion at a gas station.
That said, everybody does seem to agree that being distracted by your phone at a gas station can lead to all kinds of problems, and that seems true.
I can see extreme cases of phones being dropped or run over and batteries failing and exploding or getting very hot, but if gas stations felt this was a big enough risk, I’m sure they’d be much more vigilant about policing phone usage than they currently are.
That said, gas stations are inherently a bit dangerous, and it seems a much bigger problem than phones are big, itchy sweaters. Well actually, the static electricity caused by things like big sweaters. In fact, our pals at PEI even have this video of a static-related fire right on the same page as they tell you not to worry about cellphones:
Yikes! PEI did a study tracking refueling fires that appear to be static related from 1992 to 2010 and came up with some interesting results, based on 176 incidents:
“The author of this report is not an expert on static electricity. It does appear to many people in the industry, however, that electrostatic charging was the probable cause of the fires. In many of the reports we received, the refueler became charged prior to or during the refueling process through friction between clothing and the car seat to such an extent that electrostatic discharges to the vehicle body, fuel cap or dispensing nozzle occurred. Eighty-seven (87) fires occurred when the fueler returned to the vehicle during the refueling process and then touched the nozzle after leaving the vehicle. Thirty-nine (39) reports described fires before the refueling process began, when the fueler touched the gas cap or the area close to it after leaving the vehicle. Thirty (32) fires do not involve either of these two fact situations. In all but two of these cases the fueler was not the source of the electrical discharge and the source of ignition cannot easily be determined. We received insufficient information on seventeen (17) fires reported by NHTSA to confidently categorize them.”
So, while nothing here is absolutely conclusive, the part about “87 fires occurred when the fueler returned to the vehicle during the refueling process and then touched the nozzle after leaving the vehicle” is interesting, and I suppose if you’re feeling extra cautious, maybe just stay outside when you’re filling up your car.
Let’s recap our gas-filling safety lessons here:
1. It’s likely nothing bad will happen to you if you refuel with your car running, but it does introduce needless risk, and besides, why do it? It doesn’t make you look cool.
2. Cellphones, when used normally, aren’t going to set your car on fire.
3. Static electricity, though, that might actually set your car on fire.
I think good refueling practice would be to shut off your car, use your phone if you want, just don’t get all distracted and do stupid things, and maybe touch something metal and grounded (like one of the poles near the pumps or the metal barriers by them) to discharge your static electricity before you start filling up.
Sound good to everyone?