When firefighters snuff out the last remaining flames of burning structure and the fire is declared under control, the men frequently need to re-enter the interior of the building to administer an overhaul operation consisting of a set of protocols that includes a search for hidden fire. Rekindle is the fear of every fire chief, and the extinguishment of persevering embers that can rekindle into a new fire is the most essential element in an effective fire overhaul operation.

Firefighting is extremely dangerous work, and during overhaul, firefighters are required to enter structurally compromised structures to open up walls, ceilings, and other types of void space to seek out those still-burning embers. During overhaul, there may not be smoke, but there is still a significant risk of exposure to some extremely hazardous toxic gases and other by-products of combustion. Science tells us that a post-fire environment can be even more hazardous to first responders than the original fire. After the fire the structure will have very likely been doused by thousands of pounds of water by the firefighting crew. The weakened supporting structures of the building combined with the weight of all the water can create an increased risk that the building will collapse with the firefighters in it. As serious as this seems, the real danger may be in that which cannot be seen.

In view of the above risks, all fire departments should establish overhaul protocols that stress the use of respiratory protection during the overhaul phase of a fire response operation. In many fires, high concentrations of formaldehyde, hydrogen cyanide and other airborne poisons bearing carcinogens are present in the environment even when the most negligible amounts of smoke are present. During overhaul, first responders without respiratory safety gear are often exposed to extremely toxic gases that exceed the limits established by OSHA (Occupational Safety and Health Administration).

To become more safe, firefighters need to be better educated about all their respiration safety gear including the SCBA and the way it functions. Their Fire Service Respiratory Protection Training should leave them adequately trained on every aspect of this gear, and the importance of using it during overhaul. Firefighters should understand the limits of their equipment and what constitutes a low air emergency, so they can respond appropriately.

Exposure to the by-products of incomplete combustion of synthetic materials and unknown chemicals places rescue personnel at an unnecessary level of risk and the practice should be avoided. It can be simply by using the equipment that we already have. Today's improved air management technology and techniques combined with supplementary work/rest interval training will generate measurable progress in the area of firefighter health and safety. Because overhaul can be more physically demanding than fighting the original fire, there should be an added emphasis on overhaul safety protocols with respect to clean air management.