The B rating on an extinguisher indicates effectiveness against which type of fire?

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Multiple Choice

The B rating on an extinguisher indicates effectiveness against which type of fire?

Rating labels show what kind of fire an extinguisher is designed to fight. The B rating is for fires involving flammable liquids such as gasoline, oil, solvents, and other liquid fuels. These fuels burn in vapors that can spread quickly, so B-rated extinguishers are built to control or suppress those vapors and cool or smother the liquid to prevent reignition. The agents used (like dry chemical powders or foam) help interrupt the chemical reactions at the flame and create a barrier between the fuel and the air. This differs from fires involving ordinary combustibles (wood, paper, textiles), which require a Class A extinguisher; fires in energized electrical equipment require a Class C approach (or a combined BC/ABC extinguisher that is safe for electrical fires); and fires involving combustible metals require a Class D extinguisher with metal-specific agents.

Rating labels show what kind of fire an extinguisher is designed to fight. The B rating is for fires involving flammable liquids such as gasoline, oil, solvents, and other liquid fuels. These fuels burn in vapors that can spread quickly, so B-rated extinguishers are built to control or suppress those vapors and cool or smother the liquid to prevent reignition. The agents used (like dry chemical powders or foam) help interrupt the chemical reactions at the flame and create a barrier between the fuel and the air.

This differs from fires involving ordinary combustibles (wood, paper, textiles), which require a Class A extinguisher; fires in energized electrical equipment require a Class C approach (or a combined BC/ABC extinguisher that is safe for electrical fires); and fires involving combustible metals require a Class D extinguisher with metal-specific agents.

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