What exactly is a backdraft?
This is a deadly fireground phenomenon sometime referred to as a “smoke explosion”, which can occur in a confined fires during the late stages of the free-burning phase or in the smoldering phase. During this period, burning becomes incomplete because of the relative lack of oxygen (the fire has used it up) will no longer sustain open burning. However, the heat which built-up during the free-burning phase remains in the closed structure and the unburned carbon particles and other flammable products of combustion are contained and waiting to burst into rapid, almost instantaneous combustion when a fresh supply of oxygen is introduced into the atmosphere. If a door, window, or improperly placed ventilation hole is opened, the needed oxygen can rush in and the stalled combustion process will immediately resume with the incredible force and devastating speed of an explosion, accompanied by the renewal of intense burning. Along with backdraft the other dangerous condition that firefighters
