Which element is NOT part of the fire triangle?

The concept of the fire triangle is foundational in understanding how fires ignite and sustain themselves. The fire triangle consists of three essential components: heat, fuel, and oxygen. Each of these elements plays a critical role in the combustion process. Heat is the energy source that raises the material to its ignition temperature. Fuel is any combustible material that can burn, and oxygen is the oxidizing agent that supports the chemical reactions occurring during the fire.

Water, while commonly associated with extinguishing fires, is not a component of the fire triangle. Instead, its primary role is to remove heat from a fire, thereby disrupting the triangle by reducing the temperature below the ignition point. This is why it is identified as the element that is not part of the fire triangle. In summary, the fire triangle illustrates the necessary conditions for fire to occur, while water functions as an effective extinguishing agent by affecting one of those conditions—specifically, the heat.