Fire and Emergency Services Training Institute (FESTI) Entry Exam 2025 – 400 Free Practice Questions to Pass the Exam

Flashover and backdraft are both critical fire behavior phenomena that represent the intense dynamics of fire development and energy release.

Flashover is the rapid transition of a fire to a fully involved state, which occurs when the heat in a room becomes sufficient to ignite all the combustible materials present simultaneously. This phenomenon can lead to extremely hazardous conditions for anyone within the vicinity, as the temperature can rise dramatically in a very short period.

Backdraft, on the other hand, occurs when a fire in a confined space has consumed the available oxygen, resulting in a smoldering state. When fresh air is suddenly introduced, such as when a door or window is opened, the accumulated flammable gases can ignite explosively due to the sudden influx of oxygen. Understanding both of these phenomena is crucial for firefighting strategies, as they inform decisions such as ventilation and approaches to suppress the fire safely.

Combustion and smoldering, while important aspects of fire behavior, do not represent specific phenomena in the same context as flashover and backdraft. They are more general processes involved in how materials burn rather than defined transitions or explosive reactions that can occur during a fire event. Similarly, flashover and smoke are interrelated but again do not encompass the unique explosive nature and