Which is a characteristic of Class A fires?

Class A fires are specifically characterized by the involvement of ordinary combustible materials. These materials include common substances such as wood, paper, fabric, and other similar materials. The key point about Class A fires is that they can be extinguished using water or other agents that cool the burning material, effectively stopping the combustion process by lowering the temperature below the ignition point.

While the other options mention fire hazards, they pertain to different categories. For instance, electrical hazards relate to Class C fires, which involve electrical equipment. Fires caused by cooking oils are classed as Class K fires, typically dealt with in commercial kitchens. Flammable liquids are associated with Class B fires, which involve liquids that can easily ignite and are often extinguished using foam or dry chemical agents.

Understanding that Class A fires are related to common combustibles helps in recognizing the proper methods of extinguishment and the appropriate fire safety equipment to use in various scenarios.