Which of the following is not a characteristic of AFFF?

• A. It should be plunged into fuels
• B. It is effective against polar solvent fires
• C. It forms a blanket over flammable liquids
• D. It can be used in both fresh and saltwater

Answer: (A)

The correct choice indicates that plunging Aqueous Film Forming Foam (AFFF) directly into fuels is not a characteristic of this firefighting agent. AFFF is specifically designed to be applied over the surface of flammable liquids, allowing it to create a protective film that seals off vapors and suppresses the fire. The method of application is critical; rather than submerging or plunging it into fuels, the foam should flow across the surface to effectively form a blanket.

When considering the other characteristics, AFFF is indeed effective against polar solvent fires and can create a blanket over flammable liquids, both of which enhance its fire suppression capabilities. Additionally, AFFF can be utilized in both fresh and saltwater environments, making it a versatile tool in firefighting scenarios involving various types of water bodies. Thus, while the other options highlight the strengths and applicable uses of AFFF, the action of plunging it into fuels contradicts its intended application method and function.