Fire rollover occurs when superheated, unburned gases rise and collect near the ceiling of an enclosed space. As these gases mix with oxygen and reach ignition temperature, they ignite suddenly, creating rolling flames across the upper layer of the room. This can happen even when materials on the floor have not yet caught fire. Flashover is a more extreme stage of fire development. It happens when heat from the fire raises the temperature of all exposed combustible surfaces in a room to their ig

From the air, USFWS crews use a Plastic Sphere Dispenser to release small ignition spheres that look like ping pong balls. Each sphere is filled with a chemical oxidizer and injected with fuel just before it is dropped. After a short delay, the reaction ignites when the sphere hits the ground. This creates a tiny spot fire exactly where planners intend it, allowing large areas to be ignited safely and efficiently without putting firefighters in hazardous terrain. Prescribed fire crews use this m