Fueling a car the wrong way can be hazardous to your health, as just a few innocent mistakes can cause a dangerous flash fire sparked by static electricity.
He’d never seen a gas pump fire sparked by static electricity before, but all it took was a quick check of the immediate surroundings for Lynchburg, Va., Fire Department Marshall Greg Wormser to see how catastrophic such a blaze could be without the quick thinking of gas station staff and firefighters.
“With that kind of fire, there are several thousand gallons of gas that are right beneath the pumps underground,” says Wormser, who was on the scene in November for a gas pump fire in the rural western Virginia community. “And that fire can burn as long as that fuel is there.”
About 100 static-sparked fires occur at gas stations each year, according to Fowler Associates, a Moore, S.C.-based electrostatic research and consulting firm. The fires most often result from easily avoidable mistakes committed by a driver while fueling. “I’ve worked on these tragic accidents, and have seen cars blow up from static at the gas pump,” says John Fagan, professor of electrical and computer engineering for the University of Oklahoma in Norman, Okla.
Fagan says these fires start with the static electricity that all cars accumulate while driving as air passes over them. Static electricity is especially problematic when it’s cold and dry — 10 to 15 percent humidity or less — making winter the prime time for static fires.
During fueling, fumes can leak from both the fuel tank and the pump nozzle. If you get in and out of the car several times, the car's static electricity can be transferred to your body. If enough static is built up, it can cause the vapors to ignite if you come too close to the fumes near the pump. “The fuel doesn’t ignite, but the vapor from the fuel,” Wormser says.
The Lynchburg, Va., blaze was caused when a woman started pumping gas, then went back into her pickup truck to get her cell phone. After exiting her truck, she touched the gas pump and there was a spark. The truck quickly caught fire, melting the gas pump and burning the truck. “It was a case of someone doing something that was an unsafe act. She went into a car and came back out,” Wormser says.
Fortunately, the station had an emergency shut-off program that was quickly triggered by staff to restrict the underground fuel being supplied to the gas pumps. As such, the blaze, which started quickly and was described by the fire department as a “total fireball up under and around the vehicle,” was contained before there were any injuries. Damages of around $20,000 were incurred by the station, and the vehicle received several thousand dollars worth on its own.
To avoid static fires, Fagan suggests not getting in and out of your car while pumping gas, wearing shoes with rubber soles that can “ground” you, and discharging static by touching the nozzle tip to a metal surface that’s away from the gas tank before fueling. Fagan says a spark is also possible when the nozzle touches the metal ring of the gas tank opening.
Advice like this has helped reduce static fires. Fowler Associates estimates there were about 1,000 of these fires a year as recently as six or seven years ago, about ten times the current rate.
Steve Fowler, president of Fowler Associates, says it’s possible for motorists to become lax as static fires temporarily fade from the public consciousness. There may be fewer, but the fires aren’t less dangerous, he says. “People have a short memory cycle about these things.”
Static fires received a lot of attention about a decade ago, after a couple of infamous gas station blazes, one in Oklahoma that resulted in a fatality and another in Las Vegas that caused the victim to become severely burned. Surveillance footage from the Oklahoma fire eventually wound up on the Internet, creating a sensation.
The national news media picked up on the issue, with network news magazines and cable networks such as CNN running investigative reports. Amid the furor, gas companies such as ExxonMobil installed signs at gas pumps warning consumers to remain at the nozzle while fueling, not to get back into the car while the gas is pumping, and not to pull the nozzle out of the tank during a fire. Most gas nozzles now have warnings of the danger of static fires as well.
Mechanical preventative measures have also been introduced, such as the OPW Nozzle, a touchpad designed in part by Fowler that grounds the user when a driver touches the nozzle. Other protective devices include covers for nozzles that prevent fumes from escaping during fueling.
“These fires don’t necessarily happen everyday, so people tend to take it lightly. But it’s a very serious issue,” says Charles Sunderhaus, a risk manager with OPW Fueling Components in Cincinnati, Ohio, which has produced a video of “dos and don’ts” for the gas pump.
Most of the warning signs from OPW and trade groups like the Washington, D.C.-based American Petroleum Institute stress not getting in and out of the car while refueling, because it’s been found that most static fires start that way. Fowler says 80 percent of static fires are re-entry/exit fires, and 80 percent involve women. One theory for why more women are involved in static fires is that perhaps women go back into their cars to get a credit card or cell phone from their purse, whereas most men carry their wallets and cell phones on their person.
But even if you do get in and out of the car, it’s still easy to prevent a static fire. “If you grab the steering wheel or the side of the car, you discharge and then you aren’t carrying static electricity,” says Bob Renkes, executive vice president and general counsel for the Petroleum Equipment Institute in Tulsa, Okla.
These preventive measures and informational campaigns are combining to make static fires relatively rare, especially considering that there are about 160,000 gas stations in the U.S. handling about 12 billion refuelings each year, according to the American Petroleum Institute, based in Washington D.C. But most experts say that educating the public more than any physical device at the gas station is the best way to insure safety.
“The strongest tool in the prevention tool box is people knowing that these fires do in fact occur, and know the conditions under which they occur,” says Robin Rorick, a spokesman for the American Petroleum Institute.