Is Hand Sanitizer Flammable?

After the pandemic, hand sanitizer went from a convenience store afterthought to a household essential. It is in our cars, our bags, at the entrance of every store, and on desks everywhere. We pump it onto our hands multiple times a day without a second thought. But given that most hand sanitizer is basically alcohol in gel form, how much of a fire risk is it really?

Yes, hand sanitizer is highly flammable. Most hand sanitizers contain between 60% and 95% ethyl or isopropyl alcohol, which gives them a flashpoint as low as 63°F (17°C). This means hand sanitizer can ignite at room temperature. Both the liquid and the vapors from freshly applied sanitizer are flammable.

In this guide, I want to cover why hand sanitizer is such a fire risk, real incidents that have occurred, and how to use and store it safely. If you are interested in how different types of alcohol behave around fire, that is worth reading too.

Why Is Hand Sanitizer So Flammable?

The active ingredient in hand sanitizer is alcohol, either ethanol or isopropyl alcohol. The CDC recommends sanitizers with at least 60% alcohol content to be effective against germs. At 60% alcohol, you already have a very flammable product. Many sanitizers contain 70% or higher.

The gel form does slow evaporation slightly compared to liquid rubbing alcohol, but the fire risk is essentially the same. When you apply hand sanitizer, the alcohol begins evaporating immediately, creating flammable vapor around your hands and in the immediate area.

The risk is highest in the first 10 to 15 seconds after application, before the alcohol has evaporated. During this window, your hands are essentially coated in a thin film of flammable liquid.

Have Hand Sanitizer Fires Actually Happened?

Yes, and they are more common than you might think. There are documented cases of people catching fire after applying hand sanitizer and then touching a static source, lighting a cigarette, or reaching toward a gas stove.

In laboratory and hospital settings, hand sanitizer dispensers mounted near electrical switches or equipment have caused flash fires when the vapor was ignited by a spark. Some hospitals have had to relocate dispensers and establish guidelines about placement near ignition sources.

During the pandemic, when people began storing large quantities of hand sanitizer in their homes and cars, fire departments saw an uptick in related incidents. Bottles left in hot cars can build up pressure and leak, creating a flammable situation inside the vehicle.

Is It Dangerous to Leave Hand Sanitizer in Your Car?

This has been a widely discussed concern. During summer months, car interiors can reach temperatures of 150°F to 170°F, which is well above the flashpoint of hand sanitizer. At these temperatures, the alcohol is actively vaporizing and could potentially ignite from a spark.

The realistic risk of spontaneous combustion is very low because you need both flammable vapor AND an ignition source. A bottle of hand sanitizer sitting in a hot car is not going to burst into flames on its own. However, if the cap is loose and vapor is building up, introducing a spark from static electricity or a cigarette lighter could be a problem.

The bigger concern with hot car storage is that the bottle can leak or the cap can pop off, spilling alcohol-based gel inside your vehicle. It is better to store hand sanitizer in a cool location and bring it with you when you go out rather than leaving it in a hot car permanently.

Are Non-Alcohol Hand Sanitizers Safer?

Non-alcohol hand sanitizers typically use benzalkonium chloride as the active ingredient. These products are not flammable, which eliminates the fire risk entirely. However, the CDC and WHO both state that alcohol-based sanitizers are more effective at killing most types of germs.

If you work in an environment where fire risk is a significant concern, like near welding operations, in a kitchen, or around open flames, non-alcohol sanitizers are a reasonable alternative. Just understand that you may be trading some germ-killing effectiveness for fire safety.

How Should You Use and Store Hand Sanitizer Safely?

Use hand sanitizer away from open flames, candles, gas stoves, and any source of sparks. After applying, rub your hands together until the sanitizer is completely dry before touching anything. This usually takes about 15 to 20 seconds.

Do not use hand sanitizer and then immediately light a cigarette, use a lighter, or touch a hot stove. Wait until your hands are fully dry and the alcohol has evaporated.

Store hand sanitizer at room temperature in a cool, dry place. Keep it away from heat sources and out of direct sunlight. If you buy in bulk, store extra bottles in a closet or cabinet rather than in the garage or a car.

For homes with children, keep hand sanitizer out of reach when not in use. Beyond the fire risk, ingestion of alcohol-based sanitizer can be toxic to small children.

Hand sanitizer is an important hygiene tool, and for most people, the fire risk is manageable with basic awareness. Just remember that you are putting a flammable liquid on your skin every time you use it. Let it dry completely before going near any heat or flame source, and you will be just fine.

Related: Is rubbing alcohol flammable? | Is bleach flammable?