Eng. Maria Lappano, analyst of risk of major accident and expert in fire safety engineering, signs an article on the issue of July 2018 of the magazine Antincendio about the phenomenon of backdraft entitled: “The ‘Backdraft’: an incidental dynamic as complex as it is fascinating dramatic. ”
The abstract of the article is shown below:
“In the event of a fire developing inside a compartment, the hot smoke plume creates a call of fresh air from the inside and possibly subsequently from the outside of the compartment in order to sustain the fire and grow it up to that combustible products will be available in the reference environment.In the condition in which there is oxygen deficiency in the compartment and it is used in the combustion phenomenon faster than it can be restored, a reduction in oxygen concentration will be observed, generally accompanied by a proportional increase in temperature As the oxygen concentration decreases, the flames will begin to shut down without blocking the development of combustion products including flammable gases, depending on the size of the compartment and the power of the fires established. will generate a quantity of combu products gaseous buildings that will tend to spread throughout the useful environment. These conditions will therefore be very susceptible to a possible new intake of oxygen to resume life and create a mixture that could ignite with extreme speed with lethal consequences: giving rise to the so-called “Backdraft”. The “Backdraft” has a real explosive force; to give an idea of its power, just think that it could determine the collapse of glass and walls. The explosive strength of a Backdraft is the result of the amount of overheated gas and oxygen present in the environment. This phenomenon is, in fact, caused by the introduction of fresh air (oxygen) into a latent fire (overheated gas), which allows, for speed and shuffling, to the hot gases of the fire to enter their field of flammability and ignite with explosive force “.
At this address it is possible to download the first page of the same.