What Is a Fire Flashover

Flashover is a thermally-driven event during which every combustible surface exposed to thermal radiation in a compartment or enclosed space rapidly and simultaneously ignites. Flashover normally occurs when the upper portion of the compartment reaches a temperature of approximately 1,100 °F for ordinary combustibles.

What are the signs of a flashover?

• High heat conditions or flaming combustion overhead.
• The existence of ghosting tongues of flame.
• A lack of water droplets falling back to the floor following a short burst fog pattern being directed at the ceiling.

What is flashover and why is it so dangerous?

Unlike their fictitious counterparts in the movie “Backdraft,” these firefighters were watching out for a substantially more dangerous phenomenon called “flashover.” Unlike a backdraft–when oxygen-starved fires suddenly reignite after receiving a new source of air–a flashover occurs with much greater frequency when …