Firefighting and Rescue ICS, Safety, Fire Chemistry, and Equipment Practice Test

Fire cannot start or continue burning unless three elements are present: fuel, oxygen, and heat. Fuel is any material that can burn, such as wood, gasoline, or other combustible substances. Oxygen is the oxidizer in the air that supports the chemical reaction, and heat provides the energy to reach ignition temperature and sustain the flame. If you remove any one of these, the fire goes out: cooling lowers the temperature below what’s needed to keep burning, removing the fuel eliminates the material to burn, and limiting oxygen disrupts the oxidizing process. The other options don’t list these three fundamental components, so they don’t match the essential trio that defines the Fire Triangle.