UNDER PRESSURE EXTINGUISHING TECHNIQUE
A flame front is exiting the upper half of a lounge window (Over Pressure – Air Exhaust) with three polyurethane (PU) foam chairs involved in this room fire, which are decomposing and giving off high energy combustible gases (smoke) feeding the fire.
Fire-fighters apply three small squirts of water spray droplets from a TFT nozzle on the Under Pressure (Air Intake) into the bottom half of the lounge window where there are no flames.
This high energy flame front is put in check instantaneously with a minimal amount of WATER and no longer runs up the upper half of the building. And, if you look carefully, following the vapour conversion trail, you can see the water vapour (white steam) travel up the ‘Air Track’ upwards into the soffit of the roof and assist in preventing extension to the attic.
A full explanation of this technique and it’s operational application is available in the book – Smoke Burns.
John Taylor 12 August 2015