What describes a backdraft in fire scenarios?

A backdraft is a dangerous phenomenon that occurs in a fire situation when a build-up of unburned gases is present in a confined space, such as a room or building. When the conditions are right, if an opening is suddenly created (for example, by a door or window being opened), fresh oxygen enters the environment. This influx of oxygen can ignite the accumulated gases, leading to an explosive combustion event.

Understanding this, it becomes clear why letting oxygen back into a contained fire is a critical component of a backdraft scenario. The sudden introduction of oxygen can shift the fire dynamics dramatically, turning what may have been a smoldering situation into a rapidly spreading and potentially uncontrollable blaze. Firefighters are trained to recognize the signs of a potential backdraft, such as smoke puffing in and out of openings, and they use various tactics to mitigate the risk.