Which types of fires should NOT be extinguished with a Type B extinguisher?

A Type B extinguisher is specifically designed for flammable liquids and gases, making it effective against Class B fires. However, when it comes to Class A and Class C fires, a Type B extinguisher is not suitable.

Class A fires involve ordinary combustible materials such as wood, paper, or textiles, and using a Type B extinguisher would not effectively address these types of materials, as they require different firefighting methods, often involving water or foam that can extinguish burning solids.

Class C fires involve electrical equipment. Using a Type B extinguisher can be risky because the contents may conduct electricity, posing a danger of electric shock or equipment damage. Instead, Class C fires are best handled with extinguishers specifically rated for electrical fires, such as Class C extinguishers or other types suited for that hazard.

Class D fires involve combustible metals, and while a Type B extinguisher will not work effectively on such fires, it also should not be used since specific dry powder extinguishing agents designed for Class D are required to manage these risks correctly.

Thus, a Type B extinguisher should not be used to extinguish Class A, Class C, or Class D fires, as it is not effective in