Class B foam is used for which type of fire?

Class B foam is specifically designed for fighting fires involving flammable liquids. These types of fires can include those caused by substances like gasoline, oil, and other hydrocarbon fuels. Class B foam works by forming a blanket over the burning liquid, smothering the fire, and preventing vapors from escaping, which helps to extinguish the fire effectively. This unique property of forming a film over the burning liquid makes it particularly effective at suppressing flammable liquid fires, as it reduces the likelihood of reignition and provides thermal insulation for the surrounding area.

In contrast, other fire classes are addressed by different methods and fire suppression agents. Electronic equipment fire suppression typically involves agents that do not conduct electricity, such as certain types of clean agents or CO2. Fires involving combustible metals often require specialized extinguishing agents due to the unique characteristics of metals such as magnesium or sodium that can react violently with water. Fires involving organic materials are generally classified as Class A fires, which are best suppressed with water or Class A foam. Thus, Class B foam's specificity makes it the right choice for flammable liquid fires.