Spray sunscreen, often packaged in an aerosol can, offers a quick and convenient method for sun protection, but it introduces a unique hazard many users overlook. The direct answer to whether this product is flammable is yes, spray sunscreens can catch fire. This flammability risk is explicitly due to the ingredients required to create the fine mist and the aerosol application system. This danger is present not only during the spraying process but also on the skin immediately following application.
The Chemical Reason for Flammability
The flammability of aerosol sunscreen is directly linked to the ingredients necessary for the product’s function and spray delivery. Many formulas contain volatile solvents, most commonly denatured alcohol (ethanol), which helps the sunscreen formula spread evenly and dry quickly on the skin. Alcohol is a highly flammable substance that vaporizes rapidly, and its presence in the mist contributes to the product’s ability to ignite. The delivery system relies on pressurized hydrocarbon propellants, such as butane, isobutane, or propane, to push the liquid formula out of the can in a fine spray. The combination of the flammable solvent and the combustible propellant creates the fire risk capable of igniting if it encounters a heat source or open flame.
Documented Risks and Real-World Hazards
The inherent flammability of the ingredients has led to documented instances of severe burn injuries. The U.S. Food and Drug Administration (FDA) has acknowledged that spray sunscreens pose a flammability risk, even after the product has been applied to the skin. The agency has investigated multiple incidents where people suffered significant burns after applying the product near a source of ignition. The fire risk is not limited to the moment of spraying, but persists on the skin until the flammable ingredients have fully evaporated. The residual alcohol and propellants coating the skin can ignite, resulting in a flash fire that follows the pattern of the applied sunscreen, often resulting in second-degree burns.
Safe Application and Storage Guidelines
Mitigating the flammability risk begins with careful application, ensuring no heat source is nearby during the process. Users should never apply spray sunscreen near an open flame, spark, or source of heat, including pilot lights or cigarettes. Maintain a distance of at least 6 to 10 feet from any potential ignition source while spraying. After application, wait until the sunscreen has completely dried on the skin before approaching a grill or engaging in activities near fire.
Storage Guidelines
The storage of aerosol sunscreen requires attention to temperature constraints. Because the containers are pressurized, they can explode if exposed to excessive heat. Product labels warn against storing the can at temperatures above 120°F (49°C). This means avoiding leaving the aerosol can in direct sunlight, a hot car, or near other high-temperature environments to prevent dangerous pressure buildup.