What type of foam is commonly used for combating flammable liquid fires?

• A. Class A foam
• B. Class B foam
• C. Alcohol-resistant foam
• D. Dry chemical foam

Answer: (B)

Class B foam is specifically designed for combating flammable liquid fires, making it the most appropriate choice for this situation. This type of foam is formulated to extinguish fires involving petroleum products, solvents, and similar flammable liquids. It works by creating a barrier between the fuel and the air, which helps to suppress the fire, cool the surrounding area, and prevent re-ignition.

Class A foam, in contrast, is intended for ordinary combustibles like wood, paper, and textiles, and while it can help with some fire scenarios, it is not ideal for flammable liquid fires. Alcohol-resistant foam is a subtype of Class B foam that is particularly effective against alcohol-based fuels, but it is not as universally applicable to all types of flammable liquids. Dry chemical foam can suppress flames, but its primary function is not to blanket flammable liquids effectively and may not provide the same protective foam blanket that Class B foam does. Thus, Class B foam stands out as the correct answer for effectively handling flammable liquid fires.