Can hand sanitizer catch on fire in a hot car? Here’s what experts say

Can hand sanitizer really catch on fire if left in a hot car?

As temperatures heat up across the U.S. and more people carry the flammable product because of the coronavirus, firefighters in Wisconsinare warning of potential risks.

The Western Lakes Fire District posted a photo of a burned vehicle on Facebook, telling followers to be cautious about leaving hand sanitizer bottles in vehicles. It quickly received thousands of shares.

“Keeping it in your car during hot weather, exposing it to sun causing magnification of light through the bottle, and particularly being next to open flame while smoking in vehicles or grilling while enjoying this weekend can lead to disaster,” the fire department said.

The post did not say if Western Lakes firefighters had responded to such a fire.

How worried should we be about this happening?

Generally speaking, public health officials and firefighters agree the benefit of using sanitizer to prevent spreading germsgreatly outweighs the risk of it catching on fire.

According to the World Health Organization, a 2007 study estimated more than 9.2 millions gallons of hand sanitizer were used at hospitals with reports of seven “non-severe” fire incidents reported.

“No reports of fire caused by static electricity or other factors were received, nor were any related to storage areas,” according to WHO.

The National Fire Protection Association agreed the risk is low for individual use, though it warned about the risk of storing large quantities.

Fact-checkers said the internal temperature of car needs to reach 572 degrees Fahrenheit for a bottle of hand sanitizer to combust, according to The Poynter Institute. Arizona State University researchers found that vehicles in triple-digit temperatures reached a maximum of about 160 degrees Fahrenheit, according to Poynter.

However, hand sanitizer is relatively easy to ignite.

Alcohol-based hand sanitizer — the type recommended by health experts — contains ethyl alcohol, which can evaporate into an “ignitable vapor” at room temperature, according to the Centers for Disease Control and Prevention.

Still, leaving hand sanitizer in your car can be a bad idea — but not necessarily related to fire, experts say.

Hand sanitizer should contain at least 60% alcohol is important to killing germs, the CDC says. People should avoid leaving hand sanitizer where temperatures will increase, Greg Boyce, a chemistry professor at Florida Gulf Coast University told WZVN.

“So over a longer period of time at higher temperatures, you lose some efficacy in a hand sanitizer because the active ingredient evaporates,” Boyce told the news outlet.