What portable firefighting extinguisher is intended for use on a Class "B" Fire?

The Aqueous Film Forming Foam (AFFF) extinguisher is specifically designed for suppressing Class "B" fires, which involve flammable liquids such as gasoline, oil, and paints. AFFF extinguishers work by forming a barrier or film on the surface of the flammable liquid, which helps to smother the fire and prevent the release of flammable vapors. This film not only cools the burning material but also assists in preventing re-ignition.

AFFF's effectiveness is particularly noteworthy because it can be utilized both on solid combustibles and flammable liquids, making it versatile for various firefighting situations that one may encounter, especially on naval vessels or industrial environments where such materials are prevalent.

Understanding the specific function of each extinguisher type is critical for ensuring the correct approach to firefighting protocols. The CO2 extinguisher, while effective for electrical and some flammable liquid fires, does not provide the film-forming capability that AFFF does. Water extinguishers are inappropriate for Class "B" fires as they can actually spread the burning liquid. Dry chemical extinguishers can also extinguish Class "B" fires, but they do not have the same vapor suppression properties as AFFF.