Which foam type is commonly used for Class B fires involving fuel?

Aqueous Film Forming Foam (AFFF) is specifically designed for suppressing Class B fires, which involve flammable liquids such as fuels. AFFF works by creating a thin film on the surface of the burning liquid, effectively preventing the release of flammable vapors. This film aids in extinguishing the fire by isolating the fuel from the oxygen in the surrounding environment, which is essential for combustion.

The properties of AFFF enable it to spread quickly across the surface of the fuel, allowing it to cover larger areas efficiently, which is critical in emergency situations involving large fuel spills or fires. Its effectiveness in combating Class B fires makes it a standard choice among firefighters for dealing with such hazardous scenarios.

Other foam types listed may not be suitable for Class B fires, and while dry chemical powder and water mist have their uses, they do not provide the same vapor suppression and film-forming capabilities that AFFF does, making AFFF the preferred solution in these situations. Protein foam can also be used for Class B fires, but AFFF's rapid performance and effectiveness make it the more widely utilized option in various firefighting settings.