In which stage of a fire has all of the available fuel and/or oxygen been consumed and active flaming has decreased or stopped?

The decay phase is characterized by the point in a fire’s life cycle where all available fuel and/or oxygen has been consumed, leading to a significant decrease or complete cessation of active flaming. At this stage, combustion is no longer sustained due to the depletion of these essential elements, and the fire typically transitions into smoldering combustion, producing minimal heat and light.

This phase is critical in fire management, as it indicates that the intensity of the fire has significantly diminished, allowing firefighters to assess the situation for safety and begin recovery efforts. Understanding the decay phase helps firefighters to strategize effectively for extinguishment and overhaul operations, ensuring that residual heat or embers do not reignite.

Recognizing the characteristics of the decay phase is essential for effective firefighting tactics, as it alerts responders that the fire is nearing its end, but caution is still needed for potential hazards.