Florida Fire State Practice Exam

What occurs when oxygen is introduced into an oxygen-depleted room?

1. Back draft

2. Flashover

3. Smoke layer buildup

4. Fire triangle creation

The correct answer is: Back draft

When oxygen is introduced into an oxygen-depleted room, a backdraft can occur. This phenomenon happens when a fire has consumed most of the available oxygen, leading to incomplete combustion and smoke accumulation. When a fresh supply of oxygen is introduced, such as by opening a door or window, it can ignite the smoke and gases that were previously present, resulting in a sudden, explosive fire event. The backdraft is characterized by a rapid release of energy from the combustion of these gases, which can create dangerous conditions for firefighters and anyone else present. It is crucial for firefighters to recognize the signs of an impending backdraft, such as the presence of smoke that is thick and stagnant, a feeling of intense heat, or a change in smoke color. While flashover is a critical fire phenomenon related to the rapid spread of fire from one surface to another when the room reaches a certain temperature, it is not directly linked to the introduction of oxygen in the same way backdraft is. Similarly, smoke layer buildup refers to the accumulation of smoke in the upper portion of a room, which occurs over time during a fire but does not specifically relate to the sudden influx of oxygen. The fire triangle creation is a fundamental concept about the three elements needed to sustain fire (