In April 2020, photographs showing the after effects of a car fire caused by an unattended hand sanitizer bottle started to circulate on social media platforms WhatsApp and Telegram.

Most of the posts were written in Portuguese encouraging people to be aware of hand sanitizers left in their cars because of the claim that it can voluntarily combust.

After a month of being viral in Brazil, similar posts on English-language pages started to spread. Aside from anonymous social media users spreading the claim, these cautions have also been posted on official fire department pages. On May 21, the Western Lakes Fire Department of Wisconsin (WLFD) have shared related posts about hand sanitizers being left inside the car.

A short time later, different news outlets discovered the story regarding how a fire department warned people about being cautious in leaving hand sanitizers inside their cars and produced articles about it. Even though WLFD really posted the warning, it then removed the post for stirring commotion.

The circulating image has not been proven to be caused by an exploding hand sanitizer left in a car. Some experts have weighed the situation and said though hand sanitizers are alcohol-based, an enormous amount of heat is required to start up an explosion.

Although the incident may be possible, official reports regarding a car fire due to left-hand sanitizer is a must-see. WLFD stated that light magnification through plastic bottles could start up a fire, which plays true for any plastic bottle, regardless of the bottle's content.

WLFD removed their original post regarding the hand sanitizer warning and cut out with a message stating the goal of the department was only to provide accurate, timely, and educational information while responding to customer needs, preventing injury or fire from using hand sanitizer, and apologizing for any confusion made by the former post.

Though the post has been corrected, a number of people are still confused regarding the possible danger brought by hand sanitizers.

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According to a report of the Federal Aviation Administration in 2010, hand sanitizer is flammable and could easily be ignited when placed into a pan with a common grill lighter. It burns cooler than plastic, fuel, or cellulose fires. It has been observed that liquid hand sanitizers have higher temperatures above the flame than get hand sanitizers.

Vapors given off by hand sanitizers are also flammable. As stated by the Centers for Disease Control and Prevention, alcohol-based hand sanitizers contain ethyl alcohol, which at room temperature evaporates into combustive vapor. Although the recorded fire incidence related to ABHS is very low, it is important to store them safely and bulk dispensers are correctly installed and maintained.

National Fire Protection Association (NFPA) stated that in order for hand sanitizers to spontaneously combust, it requires to be exposed to tremendous heat over 700 degrees Fahrenheit. Guy Colonna, Director of Technical Services at NFPA, stated that spontaneous ignition could be met when a self-heating substance ignites without any outside ignition source and hand sanitizer itself is not subject to self-heating.

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