Foam concentrate is a liquid substance used to create firefighting foam. It is mixed with water to produce a foam that can smother fires, particularly those involving flammable liquids like gasoline or oil. The foam works by forming a barrier that prevents oxygen from reaching the fire, effectively extinguishing it. Foam concentrates come in various types, including AFFF (Aqueous Film Forming Foam) and AR-AFFF (Alcohol-Resistant Aqueous Film Forming Foam). Each type is designed for specific fire scenarios, making them essential tools for firefighters and industrial safety personnel in managing hazardous situations.