What should firefighters first assess when entering a burning structure?

In firefighting, assessing the fire conditions and potential for flashover is critical as it directly impacts the safety of both firefighters and any civilians who may be present. Flashover is a rapid spread of fire that occurs when the temperatures in a room reach a point where all combustible materials ignite almost simultaneously. Understanding the fire conditions allows firefighters to identify the intensity of the fire, the presence of smoke, heat levels, and how these factors might contribute to flashover.

Evaluating the fire conditions helps firefighters determine the safest approach for suppressing the fire and protecting lives. It guides decision-making regarding when to enter, where to apply water, and the level of protection needed for personnel. Therefore, this assessment is essential before addressing other factors such as the presence of civilians, ventilation needs, or structural integrity, as these elements would be influenced by the existing fire conditions.