What is the donut effect in firefighting?

The donut effect in firefighting refers to the circular movement of fire products, including smoke and gases, around a fire. This phenomenon occurs due to various factors, such as heat and airflow, which create a vortex-like motion. As the fire burns, it generates hot gases that rise, and these gases can create a low-pressure area that draws in cooler air from surrounding areas, resulting in circular motion.

This understanding is crucial for firefighters as it helps them anticipate smoke behavior and the distribution of gases in a burning structure, allowing them to make informed tactical decisions during firefighting operations. Recognizing the donut effect can improve safety measures and enhance efforts to contain and extinguish the fire effectively.

The other options do not accurately describe the donut effect. While expansion of smoke, backdraft occurrences, and heat rise patterns are related concepts in firefighting, they do not specifically illustrate the circular movement of fire products that defines the donut effect.