Which of the following are considered the major classes of fires?

The major classes of fires used in firefighting and safety training are Class A, Class B, Class C, and Class D. Each class represents a specific type of material involved in the fire, which affects how the fire should be fought.

Class A fires involve ordinary combustible materials such as wood, paper, and cloth. Class B fires involve flammable liquids and gases such as gasoline, oil, and solvents. Class C fires involve electrical equipment, and special precautions must be taken to ensure that the fire is extinguished without conducting electricity, which could result in shock or additional fires. Class D fires involve combustible metals, which require specific extinguishing agents for control.

In contrast, the other options do not correspond to recognized categories of fire classes in firefighting. Class I to Class IV and Class F to Class R do not exist in standard fire classifications, making them incorrect choices for identifying major fire classes. Understanding these classifications is crucial for effective fire prevention and response strategies in various environments.