How many classes of fire extinguishers exist?

How many classes of fire extinguishers exist?

• A. Three
• B. Seven
• C. Five
• D. Four

Answer: (C)

Five classes of fire extinguishers exist, each aligned with a different type of fuel you might encounter. Ordinary combustibles like wood and paper fall into one class, flammable liquids such as gasoline into another, energized electrical equipment into a third, combustible metals into a fourth, and cooking oils and fats into a fifth. Understanding these categories helps you choose the right extinguisher and avoid making the fire worse—using the wrong agent can be unsafe or ineffective. For instance, water can spread a grease fire or shock an electrical fire, while some extinguishers are designed only for specific classes. Many extinguishers are multipurpose and cover several classes, but no single extinguisher works reliably for every class in every situation. That’s why the total number of distinct classes is five.

Five classes of fire extinguishers exist, each aligned with a different type of fuel you might encounter. Ordinary combustibles like wood and paper fall into one class, flammable liquids such as gasoline into another, energized electrical equipment into a third, combustible metals into a fourth, and cooking oils and fats into a fifth. Understanding these categories helps you choose the right extinguisher and avoid making the fire worse—using the wrong agent can be unsafe or ineffective. For instance, water can spread a grease fire or shock an electrical fire, while some extinguishers are designed only for specific classes. Many extinguishers are multipurpose and cover several classes, but no single extinguisher works reliably for every class in every situation. That’s why the total number of distinct classes is five.