When you introduce oxygen into an oxygen depleted room, this is called?

Introducing oxygen into an oxygen-depleted room is referred to as backdraft. This phenomenon occurs when there's insufficient oxygen in a space that contains smoldering materials. When a door or window is opened, oxygen enters the room and can rapidly reignite any unburned gases and materials, leading to a violent explosion.

Backdraft is a specific condition in firefighting that indicates a sudden and dangerous reaction due to the presence of flammable gases that can ignite when exposed to new oxygen sources. Understanding this concept is crucial for firefighters, as it helps them recognize the risks associated with ventilating a structure that may have contained a fire.

The other terms mentioned have distinct meanings in the context of fire behavior and dynamics, relating to different scenarios of combustion and fire spread.