Which condition can lead to a "backdraft" in a fire situation?

A backdraft occurs in a fire situation when there is a sudden influx of oxygen into an area that has been starved of it, leading to a violent flare-up of combustion. This typically happens when doors or windows are opened in a smoke-filled room that has been burning but lacks adequate oxygen to sustain the fire. The introduction of fresh air allows the smoldering gases within to ignite explosively, creating a dangerous situation for firefighters and anyone present in the vicinity.

Understanding the characteristics of a backdraft is crucial for fire suppression tactics. When oxygen-depleted environments are disturbed, the existing hot gases may ignite rapidly, resulting in significant hazards. The correct answer highlights the critical role that oxygen plays in combustion and emphasizes the importance of controlling airflow in fire incidents to prevent backdraft situations.