Which of the following is NOT a Class B foam type?

Which of the following is NOT a Class B foam type?

• A. Class A foam
• B. Protein foam
• C. Fluoroprotein foam
• D. Aqueous Film Forming Foam (AFFF)

Answer: (A)

Foam extinguishing agents are grouped by the fuels they’re designed to handle. Class B foams are for hydrocarbon fuels like gasoline, diesel, jet fuel, and solvents, and they work by forming a stable foam layer that blankets the liquid and suppresses vapors while providing cooling. The formulations that fall into Class B include protein foams, fluoroprotein foams, and aqueous film forming foams (AFFF). Class A foams, by contrast, are intended for ordinary combustibles such as wood, paper, and textiles; they wet and cool those materials but aren’t optimized for hydrocarbon fires. So the option that is not a Class B foam is Class A foam.

Foam extinguishing agents are grouped by the fuels they’re designed to handle. Class B foams are for hydrocarbon fuels like gasoline, diesel, jet fuel, and solvents, and they work by forming a stable foam layer that blankets the liquid and suppresses vapors while providing cooling. The formulations that fall into Class B include protein foams, fluoroprotein foams, and aqueous film forming foams (AFFF). Class A foams, by contrast, are intended for ordinary combustibles such as wood, paper, and textiles; they wet and cool those materials but aren’t optimized for hydrocarbon fires. So the option that is not a Class B foam is Class A foam.