This article is about the phenomenon in fires. For the movie go to Backdraft (movie).

A backdraft is a situation which can occur when a fire is starved of oxygen; consequently combustion ceases but the fuel gases and smoke remain at high temperature. If oxygen is re-introduced to the fire, eg by opening a door to a closed room, combustion can restart often resulting in a near-explosive effect as the gases heat and expand.

This is a very dangerous situation, often surprising even professional firefighters.

fr:explosion de fumées de:Backdraft (Feuer)