What is the donut effect in firefighting?

The donut effect in firefighting refers to the circular movement of fire products, particularly smoke and heat, around areas of a fire. This phenomenon occurs as hot gases rise and create a low-pressure zone near the floor, causing cooler air to be drawn into the fire from the surrounding areas. This circular motion can lead to a buildup of smoke and other combustion products, which can complicate firefighting efforts and pose dangers to both firefighters and civilians. Understanding this effect is crucial for firefighters as it helps them predict fire behavior and implement effective strategies while combating fires, ensuring their safety and the safety of those they are protecting. The overall coordination and movement of heat and smoke play a significant role in determining how the fire spreads and what precautions firefighters should take.