What term describes an explosion caused by introducing fresh air into an oxygen-depleted atmosphere charged with hot gases?

The term that describes an explosion caused by introducing fresh air into an oxygen-depleted atmosphere charged with hot gases is known as backdraft. During a backdraft, the existing fire has consumed much of the available oxygen, creating a state ripe for explosion when fresh oxygen is suddenly introduced. This often happens when a door or window is opened, allowing a rush of air into a space filled with hot gases and smoke. The sudden influx of oxygen can ignite these gases, leading to a violent explosion.

Backdraft is particularly dangerous because it can occur without any visible flames, misleading firefighters and occupants regarding the actual fire conditions inside a structure. Understanding this phenomenon is crucial for fire prevention and safe firefighting techniques, as it emphasizes the importance of ventilation and knowledge about fire behavior during rescue operations.

The other options refer to different fire phenomena. Flashover occurs when a room or space reaches a temperature that allows all combustible materials to ignite almost simultaneously, a different mechanism than backdraft. A smoke explosion involves the ignition of smoke particles, but is generally not confined to the specific conditions that characterize a backdraft. Combustion is a broad term that refers to the chemical reaction that produces fire but does not address the unique circumstances surrounding oxygen-depletion and the introduction of fresh