Which statement about liquid chemical extinguishing agents is true?

Which statement about liquid chemical extinguishing agents is true?

• A. Effective against Class B and C fires; some on Class A; should be followed by water.
• B. Effective against Class A fires only.
• C. Not approved for marine use.
• D. Effective on electrical fires only.

Answer: (A)

Liquid chemical extinguishing agents are designed for multipurpose use in marine fires, especially where flammable liquids and electrical equipment are involved. They work by rapidly interrupting the chemical reactions occurring in the flame and by creating a blanket over the fuel that cools and excludes air, which is why they are effective on Class B (flammable liquid) fires and Class C (electrical) fires. Some formulations also provide cooling and smothering that can help with Class A fires (ordinary combustibles), though their primary strength is in B and C scenarios. After deployment, it’s common to follow with water to cool the area further and rinse away residues, reducing the risk of reignition and protecting equipment. This makes the statement describing their effectiveness across B and C fires, with some efficacy on A, and the practice of following up with water, the best description.

Liquid chemical extinguishing agents are designed for multipurpose use in marine fires, especially where flammable liquids and electrical equipment are involved. They work by rapidly interrupting the chemical reactions occurring in the flame and by creating a blanket over the fuel that cools and excludes air, which is why they are effective on Class B (flammable liquid) fires and Class C (electrical) fires. Some formulations also provide cooling and smothering that can help with Class A fires (ordinary combustibles), though their primary strength is in B and C scenarios. After deployment, it’s common to follow with water to cool the area further and rinse away residues, reducing the risk of reignition and protecting equipment. This makes the statement describing their effectiveness across B and C fires, with some efficacy on A, and the practice of following up with water, the best description.