what is not a required element for fire?

The element that is not required for fire is nitrogen. The three essential elements required for fire, known as the fire triangle, are heat, fuel, and oxygen. Fire cannot ignite or sustain itself without these three components. Although fire is a chemical reaction, the chemical reaction itself is not counted as a separate required element distinct from the fire triangle elements. Nitrogen, which makes up a large portion of the air, is not required for fire to occur or sustain.