What is a backdraught?

Answer 1

A backdraught is an extreme fire behaviour phenomenon involving ignition of products of combustion and pyrolisis products upon introduction of oxygen to a compartment.

Answer 2

A backdraught is an explosive and sudden reintroduction of oxygen to a fire that has depleted the available oxygen in an enclosed space. This can occur when a door or window is opened, causing a rush of oxygen to reignite the fire violently. It is a dangerous phenomenon that can lead to rapid fire spread and pose significant risks to firefighters and occupants.