Fire is one of the most powerful and dangerous forces on Earth. It can cause immense destruction and yet provide us with the power to cook food, forge metal tools, harden bricks and generate electricity. Fire is a chemical reaction that creates heat and light by breaking down the atoms of its fuel through oxidation, or the breakdown of molecules. It requires three things to start and sustain: ignition, fuel and oxygen.

Ignition is the spark that starts the chain reaction of combustion. Common sources of ignition include matchsticks, lighters, overloaded electric wires and heaters. Fuel is anything combustible, such as paper, wood, oil or gas. Oxygen acts as the oxidizer to help break down the molecules of the fuel and supports combustion by supplying energy. The speed at which fuel burns is determined by its shape and how much surface area it has to absorb oxygen. For example, wood splinters and paper burn more quickly than blocks of wood because they have a greater proportion of their surface area exposed to oxygen at any given time.

Once the fuel reaches its ignition temperature, it releases a huge amount of heat energy that rapidly heats up the oxygen surrounding it, causing a chemical reaction. The resulting gases ignite other fuel particles, and the reaction continues as long as there is enough fuel and oxygen. The flame itself also heats up the air around it, igniting it and increasing its speed of spread through convection and radiation.

Fire can be stopped in three ways: extinguishing, suffocation and decomposition (burnout). The most effective way to stop a fire is to remove its source of fuel and oxygen. This can be done by using a CO2-based fire extinguisher in the event of a small fire or pouring water over it in the case of larger blazes.

In a home environment, most fires are started by cooking accidents. The kitchen is filled with appliances that require electrical power to function, which can easily spark a fire in the event of a malfunction or misuse by an individual. In the workplace, faulty or overloaded equipment is another common source of fire.

Fire also plays a critical role in many natural habitats. For example, prairie and savanna grasslands in Minnesota, North Dakota and South Dakota thrive with regular fire and support hundreds of wildlife species including big bluestem, purple coneflower and blazing star that would not survive without it. In these areas, controlled, or “prescribed,” fire is used in combination with cattle and bison grazing to maintain a sustainable ecosystem.