In which stage of the burning process does flashover occur?

Flashover is a rapid and dramatic event in the fire development process where the entire room or area becomes engulfed in flames almost simultaneously. This phenomenon occurs when the heat in the environment reaches a critical temperature, causing the gases and materials within the space to ignite almost instantaneously.

In the context of the stages of burning, the fully developed stage is characterized by well-established fire conditions where there is an abundant source of fuel and sufficient oxygen. At this point, the temperatures have risen significantly, facilitating the conditions necessary for flashover to occur. During this stage, the combustible materials have been heated to their ignition temperatures, allowing for the potential of flashover as the heat is radiated and transferred within the space.

The other stages, such as ignition, initial growth, and ventilation-limited stages, do not provide the right conditions for flashover to occur. During the ignition stage, the fire is just starting, and temperatures are not high enough. The initial growth stage involves the fire beginning to grow but is still limited in heat output. The ventilation-limited stage describes a situation where there isn’t enough oxygen for combustion to continue efficiently, not leading to flashover conditions.

Understanding that flashover signifies the transition into the fully developed stage helps clarify its critical