How Fire Works

For thousands of years, humans have been captivated by fire. We’re drawn to its warmth, the way it illuminates dark spaces, and its ability to cook food. But there’s more to fire than meets the eye. Fire is a powerful symbol that can heal, protect and renew.

Fire has been used to clear forests of brush, restore wildlife habitat and control invasive species. It is a key natural disturbance that keeps ecosystems healthy over the long term.

However, many people think of fire as a dangerous phenomenon that can destroy homes and lives, so it is important to understand and use it safely. The best way to do this is to learn about how fire works. Fire is a complex chemical reaction that happens when combustible materials (like wood or gasoline) react with oxygen in the air to release heat energy in a process called combustion. Fire is visible only because this process of chemical transformation releases light energy in the form of flames. The color of the flame is determined by the chemical reaction that produces it.

The elements in the fuel, such as carbon and hydrogen, react with each other to produce new molecules that give the fire its color, heat and odor. The products of the reaction are water, carbon dioxide and other chemicals. The process is always ongoing and can only happen when there are 3 ingredients: heat, fuel and oxygen. This is known as the fire triangle.

To ignite the chemical reaction that produces a fire, the fuel must be heated until it reaches its ignition temperature. This is when the particles of the fuel start to break apart, and gaseous fragments escape the surface of the material and mix with the oxygen in the air. The result is a flash of bright light, then a dance of flames.

A safe fire is an essential outdoor activity that can be fun and relaxing for the entire family. Be sure to check daily burning restrictions and never leave a fire unattended. Always build your fire in a cleared area away from overhanging branches, logs and other fuels, and make sure to extinguish the fire completely.

Periodic fires help restore wildlife habitat by removing the dead organic material that can choke out young plants and prevent oxygen from reaching the soil. In addition, nutrients tied up in vegetation and dead animals are released by fire and return to the soil more quickly than when they decay over time. This is why the practice of prescribed burns is so important in western rangelands.