I’ve read about and heard from a few firefighters who have told me that they were in a room which flashed.


The mere fact that they are able to relate such an experience is almost always a clear indication that a flashover did not occur.


Certainly some type of catastrophic fire event (CFE) took place, but in
all likelihood, no one survives a flashover and lives to tell about it.

 

So what happened? 


A trick question that always gets my students is:  Does it really matter what type of CFE it truly is? 


The answer is hell yes!  Why?


If we want our crews to survive, we need to constantly be aware of the what’s going on inside the burning box we’re crawling through.  Different
CFE’s give different clues as to what will be occurring next. 


Recognizing these clues will make the difference between crawling out of the structure, or being carried out by your brothers.  You have to have the smarts to look for, recognize, and react to the constantly changing situation of an aggressive interior attack.


In the spirit of training, here is a cool video of a catastrophic fire event taken from five feet outside the door of the room.  Watch it closely as it develops, then make your guess as to what type of CFE it may be.


Above all, learn to recognize these clues and keep your brain engaged constantly next time you’re crawling through that burning
box.



FlashoverTV is powered by FireRescue1.com

This is a flashover as viewed from 5 ft away from the doorway. The fire was allowed to continue on purpose to achieve the flashover. I
captured the footage with my special camera. A secondary smoke explosion in the attic blew two sheets of tin off. I use the footage for training. Hope you can use it for instruction as well
.


John Mitchell is a fire Lieutenant and paramedic in suburban Chicago. He is a fire and EMS instructor, certified fire investigator and Chicago Blackhawks fan. He is the editor of FireDaily and co-creator of FirefighterNetCast.

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Very good video.
Now I have been in a flashover simulator and I have experienced a backdraft, the video and everything associated says flashover, but you ask a thought for what type of CFE it may be.....leads me to believe you are thinking something else. I understand the definition of a flashover being all combustibles in a room igniting simultaneously and a backdraft is a smoke explosion.

Well, here is what I see. I see fire which rapidly starts to darken down, meaning ventilation is inadequate within the room. Since the fire goes dark, the heat is building and there is a ton of superheated gas just building. From the flashover simulator, I know if such conditions are encountered, I am pencilling with short burst of straight stream, wall, ceiling, wall and getting out, pencilling if I have to and if I still have the nozzle (this is shit and get mode here).

As the video progresses, the room stays dark, but you start to see smoke starting to "suck" into the room, the smoke passes the camera into the room. At this point you see the fire starting to "grow" again and give off light as the fire is now getting more oxygen. You can see the smoke moving past the camera faster as the fire intensifies and eventually explodes. The video shows the hole in the roof which blew out after the explosion.

So given the "sucking" smoke, the violent smoke explosion as the fire got air, and the hole in the roof, I say this was a backdraft.
The key word here is "smoke explosion", I would have to agree with John with the evidence of a backdraft. A few years back here in SC there was a department that acquired a house for training. Even with all their safety briefs and walks throughout the structure before their training evolutions, they missed one key factor!

The structure had a double ceiling in it that contributed to a flashover with a crew inside the structure. Their capt. who was rescued by a RIT team, did receive burns that almost cost him his life. I will back up a step here to say that, when they started their revolution the crew that was venting the roof failed to communicate to the IC that they couldn't punch through the ceiling.

Few have survived being caught in a flashover to tell about their experience, very few! If interested, I have a video of the incident, just inbox me.
Agreed
Check out these links for the differences between flashover and smoke explosions.

http://vincentdunn.com/dunn/newsletters/dec/dec.pdf
http://www.firetactics.com/CHITTY%205-1994%20BACKDRAFT.pdf
http://www.firetactics.com/FLASHOVER.htm This source has more links at the bottom of the page

I would go with smoke explosion given that there appears to be a shock wave -in both the fire room and the room directly outside of it- at the moment of ignition.
Thanks for the links Jack. I just basically skimmed through them, but a lot of good information. Will read them later.
Well, here is what I see. I see fire which rapidly starts to darken down, meaning ventilation is inadequate within the room. Since the fire goes dark, the heat is building and there is a ton of superheated gas just building. From the flashover simulator, I know if such conditions are encountered, I am pencilling with short burst of straight stream, wall, ceiling, wall and getting out, pencilling if I have to and if I still have the nozzle (this is shit and get mode here).
Why would you pencil with short bursts of water and then get out if you encountered these conditions?
That is what is done in flashover simulators to allow the fire to keep burning (so that more evolutions can be performed) OPEN THE LINE UP AND PUT THE FIRE OUT, if you encounter these conditions in a house or building fire.....or give the line to someone that will.
You're right, to a point. But, there are instances when you will not have enough time to open up and begin extinguishment. Quickly pencil the ceiling and get your ass out, before you too ignite with the rest of the room.
I have been caught in a rollover in a training fire. I was just getting ready to open up the nozzle and the officer in charge told me "dip it down and push that running the diesel in the floor back into the fire, then quickly pick it back up to the right angle." When I dipped it down it rolled over on the 4 of us in the crew and got us really hot really fast! My brother-in-law pulled me out the fire had knocked me on my back and I barely had the nozzle. The training crew beat us out of there and called the reserve line in to help get it back under control. I had to have a new visor, new bunker pants, and new low pressure hose (old survivair packs) thank goodness it just bubbled and didn't rupture. I learned several things that day, mostly the hard way, but the most important thing that I learned was always have someone watch your back. I also have a very healthy respect for what it can do. I have been back in several times since then, but it's always in the back of my mind and I'm more careful that I used to be. I should also say that it's been 13 years ago but things like that you don't forget. Sorry to make the post so long but I felt it was relevant to the subject at hand.
Jim, I agree. I've been lucky enough to survive two flashovers and one backdraft in my career, and none of them were much like the video.

I was very near the door in both of the two flashovers, was able to self-rescue in probably two or three seconds (although they felt like forever) and was lucky to have only minor burns and ruined PPE and SCBA both times.

The backdraft was so violent that I didn't realize what happened for several seconds after it literally blew me out the door into the front yard.

I dunno if I'd call the video "kiddieville", but it certainly isn't the most catastrophic interior condition I've ever seen, either.

It is a good training video.
It would be one thing if you knew where the fire was, if you just opened up the line you have a good chance of steaming yourself, pencilling can keep the gases in check from bursting into flame so you can get out.

In this case, yeah you can see the fire and can extinguish. In the case you can't see the fire and visibility deteriotes rapidly, as here, it is time to get out.
In that kind of enclosure, if you just open up and blast the fire you're going to steam burn everyone to Larry the Lobster status.

Pencilling to prevent ignition until effective ventilation can be conducted is an appropriate technique.

It's all about technique.
The theory of short bursts of pencil, pencil, pencil, fog is for as Ben put it, to reduce the amount of steam conversion, thus reducing the cook effect on the crew who are fleeing. The nozzleman can with this technique in the right environment, delay the ignition of total flashover by introducing the small amounts of steam produced in the bursts as well as interupting the thermal balance.

With opening the bail and leaving it flowing, the super heated BTU's will steam everyone and everything inside. All about technique and timing.

Obviously best to not be there at the time through better pre-flashover techniques and timing on other fireground tactics.

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