Someone posed this question to me yesterday. I had often ‘heard’ of a person being burnt while striking a match or a lighter with hands that were still wet from an alcohol-based sanitizer; another accident seemingly stemmed from a static discharge when the victim touched a metal surface. I have seen several pictures, all from uncited sources, of burns and blisters to the hands and forearms as being proof of the flammable qualities of hand sanitizer and the likelihood of a burn with hands damp from sanitizer. But does that flammable quality apply to a container in a hot vehicle? Would the container rupture and burn? There are many variables to consider when answering that question. What temperature is ‘hot’? What is the quantity of the material in storage? How much flammable liquid by volume is in the product? Is the product in the glove box (no direct sun) or on the seat (direct sun)? What are the storage directions on the container label?
Let’s start with a bottle of 8 ounces of hand sanitizer made up of 70% ethyl alcohol that we have stored in our vehicle. For consumer use, meaning the product can be purchased over the counter and used or stored in small quantities, the best place to find information regarding that product is right on the manufacturer’s label. I looked up several different brands of hand sanitizer, both gel and foam, read the labels and each time the directions stated that the product was to be stored below 110° F. According to www.heatkills.org “At 70 degrees on a sunny day, after a half hour, the temperature inside a car is 104 degrees. After an hour, it can reach 113 degrees. When temperatures outside range from 80 degrees to 100 degrees, the temperature inside a car parked in direct sunlight can quickly climb to between 130 to 172 degrees.” How can a product that is flammable and kept in a plastic bottle in a vehicle be safe when stored in such temperatures?
I reached out to customer support at GOJO®, the manufacturer of Purell® hand sanitizer, and asked about the potential for container rupture or flash fires of their product when stored at high temperatures. I received this response: Subject: GOJO Customer Service Case #01016758I Hello, You should avoid letting the product sit in temperatures above 110 degrees F. The sanitizer is safe above that temperature but you run the risk of the alcohol evaporating. Thanks firstname.lastname@example.org. So it seems that the reason behind the storage limitations (not above 110°F) is the alcohol evaporation (quality) and not the packaging integrity (safety).
A search of the Consumer Product Safety Commission database of notices due to accidents or safety issues yielded no results. I searched several watchdog websites but did not find a confirmed case of any size container rupture of any alcohol-based sanitizer product or related accidents.
The rules are different for those businesses that store hand sanitizer product in larger quantities or transfer the product from a larger to a smaller container. Under OSHA’s Hazard Communication regulation, a safety data sheet must be available to inform employees of the hazards of this product during handling, use or storage. The SDS for Purell® gel hand sanitizer lists the hazard as a Category 3 flammable liquid and posts the pictograms for ‘flammable’ and ‘irritant’. The main ingredient of this hand sanitizer is ethyl alcohol and it has a flash point of 77° F. This means that the product starts to evaporate at that temperature. This is important to understand because, as with all flammable liquids, the vapor (not the liquid) burns so keeping any product with a Category 1-4 rating away from flames or heat sources is a must. Always review the SDS for special handling precautions before transferring hand sanitizer (or any chemical) from large containers into secondary containers.
Alcohol-based hand sanitizers must be stored away from all heat and ignition sources, including sparks, open flames, any types of electrical outlets, switches or equipment, and extreme heat. Make sure that the cover is tightly closed and that the container is not damaged in any way. Spilled hand sanitizer should be cleaned up with water immediately. For small quantity consumer use of any chemical, always read and follow the directions on the label.