Munitions Firefighting Practice Exam

Aqueous Film-Forming Foam (AFFF) is specifically designed to combat flammable liquid fires, like those producing vapors from JP-10, which is a type of jet fuel. When AFFF is applied to burning JP-10, it can create a frothy layer due to its chemical properties. The agent works by spreading across the surface of the flammable liquid, forming a film that suppresses vapor release and effectively extinguishing flames. This frothing occurs as a result of the interaction between the foam's surfactants and the fuel, leading to an efficient suppression of the fire. In contrast, water may not effectively suppress JP-10 fires since its density allows the fuel to remain on the surface and can even spread the fire. Although general foam does provide fire suppression, the distinctive property of AFFF in forming a vapour-suppressing film is crucial for effective control over JP-10 fires. Dry chemical agents can extinguish flames but do not create a film or work in the same way as AFFF when dealing with flammable liquids.