During the decay stage of a fire, what happens to the heat levels?

In the decay stage of a fire, heat levels decrease as the available fuel is consumed. During this phase, the fire has already passed its growth and fully developed stages, where it was at its peak intensity. As the burn progresses, the combustible materials are used up, leading to a reduction in both the amount of fuel available for combustion and the production of heat. As the fire consumes what remains of its fuel, the overall temperature of the fire diminishes, reflected in lower heat levels. This process is essential for understanding how fires develop and die out, which is critical knowledge for firefighters when assessing fire conditions and for strategizing extinguishment methods.