Static electricity shocks are common in everyday life. But can static electricity give enough of a shock to start a fire?
Static electricity is the result of an imbalance between negative and positive electrical charges in the body. According to the US Library of Congress. These charges can accumulate on the surface of the body until they find a way to discharge them.
The most common cause of static electricity is a phenomenon known as triboelectricity. Boria Al ShamsiA power electronics engineer at the Missouri University of Science and Technology told Live Science. When two materials repeatedly touch and then separate, the surface of one material can steal electrons from the surface of the other material. For this reason, rubbing socks on the carpet or running a plastic comb through the hair can generate electrical charges. In essence, negative electrons leave one object for another. Then, when you touch something, like your cat or dog, you'll get a shock as the extra electrons quickly leave.
If you rub a balloon on your shirt, the balloon receives an excess of electrons, whose negative charge helps the balloon stick to the wall, and is now more positively charged than the balloon, according to the Library of Congress.
The strongest display of static electricity on Earth is LightningAl Shamsi said. Collisions between raindrops and ice crystals within clouds can lead to the buildup of huge amounts of static electricity. According to the National Weather Service. Shamsi said lightning discharges can contain “up to 5 gigajoules of energy, which is enough to set several trees on fire in an instant.”
By comparison, the amount of static charge a person might accumulate is hundreds of billions of times smaller, amounting to about 40 millijoules of energy, Shamsi said. This is roughly equivalent to the power a typical LED indicator light would use in one second, According to electronics design company Cadence.
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However, Al Shamsi said: “Even this small amount of energy is enough to damage sensitive electronic devices or start a fire.”
Al Shamsi said that most human-caused static electricity fires start with flammable fuel vapors and gases. Specifically, “the most common everyday situations for a fire to start would be at gas pumps,” Mark LambertThe director of the West Virginia Fire Training Academy told Live Science.
Static electricity on a person can set off an electrical spark — on a pump handle, for example — which can set flammable materials on fire. To prevent fires at gas stations, “touch the metal or car door with your bare hand” before using the pump, Lambert said. “This will discharge static electricity on your body and will prevent the possibility of a fire.”
Most importantly, “once you pump gas, don't go back to your car,” Lambert said. “This can recharge your body with static electricity.”
Truck bed liners can also generate static electricity. “You should always remove gas cans from under the truck to fill at the pump,” Lambert noted.
Al Shamsi said that in addition to gas stations, “in industrial areas, static electricity can set fire to fine dust, including fine wood dust, aluminum dust and even wheat flour.” Powders and other materials moving within a facility can build up static electricity on surfaces which can then discharge onto dust, causing it to burn. Al Shamsi said: “The average person may not consider aluminum or the bread he eats to be a combustible material.” “But when both are ground into a fine powder, both can burn due to static electrical discharge.”
In general, Al Shamsi said: “People working with combustible fuels, including hydrocarbons and fine dust, should unload themselves before handling fuel or entering those environments.”
