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 I appreciate you asking for my opinion about this video and the LA/C use of CAFS for outside initial attack.  I have used this tactic for many years and it has never failed me to gain quick control of structure fires, even when I used to be working State and Federal forest fires that involved homes and buildings. We did not have proper PPE to inter the structures until the fire was out. I was very glad to see the window tactic in the video using a straight stream of water.  It works best when the structure has not been ventilated because the gases in the smoke are very helpful in extinguishing the fire even when they contain methane, CO, and many other flammable products of incomplete combustion. You can use the amount of smoke to read how incomplete the combustion is.  There are 3 important atmospheric conditions in a structure fire that help extinguish the combustion.  The complete combustion of oxygen turns it into CO2, incomplete combustion turns oxygen and carbon into the gases that we can see as smoke. A room full of smoke with no oxygen will not burn, in fact smoke will extinguish the fire because the room will slowly absorb the heat without oxygen.  Now here's the important reason why the straight stream of foam or water is preferred, the straight stream drags less oxygen into the room. The next most important part of the tactic is to use the streams velocity to BLAST the area of contact. When it hits the ceiling the steam spreads out in a very effective fan pattern, so it is helpful to move the stream around as much as possible to spread the fan stream over the widest area possible. This provides the most effective cooling of the hot gases and drawing in the least amount of oxygen.  Let the bubbles do the work, each micro-small bubble has a thin film of water with added surfactants in it. Each exposed bubble will absorb heat much more efficiently than water droplets because the bubble are lighter and stay in the heat longer.  The water droplets are heavier and fall out of the heat faster causing water wastes and inefficiency compared to the bubbles.  I repeat "let the bubbles do the work"  the thin films of surfactant treated water in the bubbles also attract the hydrocarbon products of combustion and actually clean the smoke out of the room instead of pushing the smoke from room to room. (not the heat).  This is getting too long so I will continue the lesson later.  I hope this makes sense to you and I would like to see as many comments from as many fire fighters as possible. 

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