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I'm confused, maybe somebody can help explain this. When I took my level 1 (recently) we were told roof ventilation would not increase fire intensity and on an interior entry sounding the floor while searching is what you need to do while searching in zero vis. Was just reading testing conclusions from UL and they say none of this stuff is accurate and in some cases more dangerous then helpful. While reading there were other techniques taught in level 1 that are contradicted and possibly dangerous or wrong.
steve
Replies to This Discussion
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Permalink Reply by John Crabbe on
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The reason not to just open up is to prevent upsetting the thermal balance, thus steaming the FFs. The "penciling" should keep the heated gases above you from combusting and thus leading to flashover. Keeping the gases in check allows you a chance to get to the seat of the fire. Essentially if you are a hose team and making a push and you start to get rollover etc, while waiting for vent or as you are making your way to the fire, "penciling" should prevent the gases from combusting and perhaps impeding egress. It also should give a chance to make a push without being cooked in the process by upsetting the thermal layering.
As for opening a window to a door, this would be an egress technique or RIT type of thing. The point of my response is to show importance of looking at things from the OUTSIDE before making a push to give one the best possible information. Since the OP questioned about signs to look for inside, if one does a good size up outside, then they can have a better chance of knowing what is going on inside.
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Permalink Reply by steve hutchinson on
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Is it a good idea to just send a 30 degree stream into the plume until it is cooled right off, or would that create way to much steam for the attack team and make them have to retreat? We were taught that use an indirect attack on the fire and it possible close the door to the area and let the steam extinguish the fire. Does this work very good? I tried it on my practical evaluation in the burn house and results were limited we had to hit the fire again. I didn't use indirect attack I gave it a good shot direct at the fire instead of indirect off the ceiling.
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Permalink Reply by 55 TRUCK on
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John I agree with Capt.Jack. It is rare that we would pencil in a actual fire. In training yes. Most times in the can we ask the students to just pencil. To keep the thermal balance and to not put out the fire.
On actual fire if it feels real hot we will send a burst up to see if it steams. If it does we just open up the same with fingers coming through the smoke. Then we push to the seat of the fire.
Will it get a bit warm? Sure, will you get burned? yes & no. PPE is all good and on properly then no. If it isn't then yes. Will you die from a little steam burn on your neck or wrist? No. Will it hurt? Of course it will.
I have yet to be steam burned. I know guys that have been.
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Permalink Reply by captnjak on
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This is where we disagree. "Penciling" or "using short bursts" as a method to get to the "seat" of the fire before fully operating line is, IMO, a mistake. If you are in an area that is in danger of flashing, it is time to open up the nozzle. Period. Cooling of areas containing high heat is what hose lines are for. There is no need to get to the traditional "seat" of the fire. With modern fire dynamics, the "seat" of the fire is all around you. You have heat and combustible gases that are just looking for a reason (air) to light up.
If you enter an area with high heat (that you think could flash), open the nozzle. Operate from a doorway, giving steam an escape route. Perform controlled horizontal ventilation ahead of the line for the same reason. Operate briefly and then let it "blow". Then resume your advance. Use all PPE properly.
There will not be too much steam for the nozzle team. Steam is not an extinguishing agent. For the most part it is a BYPRODUCT of extinguishment. If an attack is performed as I've described no one will be "cooked" or "steamed". I work in a busy area, with regular structural fires. I review injury reports (including burn injuries) for over 100 firefighters. I just do not come across firefighters with steam burns through their PPE. Not on the fire ground and not in the injury reviews. If guys are getting burned through their gear it is probably because they are going too far into the fire before COOLING the fire (opening line up fully).
No one on a hose line should be "waiting for vent". When you encounter the heat, hit the heat.
I believe the idea of getting to the seat of the fire dates back to the "legacy" firefighting our predecessors did. They had no masks or hoods. Their PPE was sub-par. Fires developed slower and did not get as hot. Fires have changed. We must too.
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Feel free to disagree if you wish. The question posed was to identify signs of an impending flashover, of which I responded much of that is going to be feeling of heat, starting to see rollover etc. If letting loose on the smoke is what you propose, then fine, I would say be ready to or already be retreating. Whereas the "penciling" technique can prevent the area from flashing and give the hose team a chance to make a further push without being steamed from f-ning up the thermal balance.
IMO, I would rather know techniques and ways to PREVENT a flashover in the first place. I would rather have situational awareness BEFORE even making entry. I want to know the conditions ahead of me, and more importantly, behind me. The whole point is to have an understanding of things even before making an entry, heck, even before getting on the rig. Worrying about the signs of a flashover or backdraft while INSIDE essentially means you are waiting too long. Either you protect your arse and get out, or you keep the situation in check as you make a push.
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Permalink Reply by Jim Conrad on
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In regards to the conditions behind you, would it not be more dangerous to let the heat and gasses to keep moving behind you as you make a push to the seat of the fire? Could the heat and smoke that you are managing by penciling keep on rolling past to possibly cut off you means of egress?
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It is not about wishing to disagree.
The hose team will NOT be steamed from messing with the thermal balance. Not if proper techniques are employed. Like the PPE, nozzle technique and controlled horizontal ventilation that I previously mentioned.
How is it that you would be "steamed" and/or forced to retreat by operating the line prior to reaching seat of fire but not steamed or forced to retreat when you operate on the ACTUAL seat of the fire, which is presumably much hotter?
There is no better way to prevent a flashover than fully opening the line and advancing to the seat of the fire. I'm all on board with guys understanding things before they even get on the rig, but anyone who thinks they have to get to the seat of the fire and have ventilation in place prior to opening line may not really understand anything at all.
For me, making a push is not about keeping anything "in check". It's about knocking the crap out of the fire as quickly as possible. We do this with water. Lots of it. And quickly. That results in the best conditions overall for all concerned.
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IMO, it is probably unlikely but not impossible for those gases that you let roll over your head to light up. Mainly because the penciling WILL provide some level of cooling to that layer and as you operate (eventually)on the seat of the fire the immediate area and adjacent areas will be cooled.
But I still believe we should knock the crap out of it first chance we get.
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That is my point here Jim. The technique is to cool those gases so it doesn't get behind you, instead it keeps things in check while you make a push to the seat. Whereas, in the past it was trained to stay low, get to the fire, and put it out. If fire and smoke rolled over you, so what. The idea of even directing a hosestream into the smoke was "unheard of" and "not what we do". Studies from NIST, Europe, etc, show that a small amount of water directed into the gases will keep it from rolling over and will not interrupt the thermal balance as say opening up or spraying a fog pattern would.
To try and place this in a scenario, say you are a hose team and you make entry into a structure with fire in the back bedrooms. You are still waiting for ventilation to be completed and notice smoke rolling down the hallway. Hitting the smoke with some short bursts will keep those gases cool to prevent a flash while awaiting vent. Once vent is complete, you can make your push to the seat of the fire and extinguish.The other aspect would be, same scenario, you are going down the hall to the bedroom, get some smoke rolling, heat increasing, may see some flameover, you make a few short bursts to cool the smoke, then make the push to the seat. You would essentially get what Captjak is talking about. Only difference is that instead of letting loose in the hallway, you prevent the smoke from getting to the point of flashing and give yourself a chance to make a push to the seat and then let loose.
In either event, the idea is that you know the conditions behind you, you are not just crawling under copious amounts of smoke and gases with your line on the way to the seat of the fire. Instead take care of what you do have in front of you to prevent things getting worse as you continue on. If conditions do get worse, then do what you can and make a calculated retreat.
My points here are not about arguing tactics and so forth. One can disagree if they so choose, I know there are many different depts out there with many different ways to train, protocols, staffing, and so forth. This is another technique out there. IMO, if one is waiting for conditions to get so bad that they believe a flashover is iminent, then they are doing things wrong. This technique isn't just about a flashover, but to prevent one from occurring in the first place.
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Makes sense to me now, be proactive and not reactive, why horizontal vs verticle venting?
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Why would you open up, spraying water all throughout the structure if you don't even have the fire located to extinguish? Say you have an apartment fire, you make entry from a stairway and advance towards the fire apartments. Are you spraying water all the way down the hallway because you have some heat, but don't have the fire located? Probably not, you're probably going to assess conditions, and go in and hit the fire.
That is the same thing here. The technique I'm talking about is while you are making that progress down and you do get some thicker smoke or start to see some rollover, to hit that to prevent it from getting behind you. You are making it sound as though one should be spraying water from the second they get to the fire floor, is that what you are saying? If you get steamed before even getting to the fire, then how does that help the situation at all?
The fact is that smoke itself contains superheated gases and can combust. The point is about knowing there are ways to control and prevent that smoke from combusting. If making one's way towards a fire and such smoke conditions are met, one can prevent that smoke from combusting and thus intensifying the situation.
As for getting to the seat of the fire and awaiting ventilation before opening the line, I'm not saying that, and if that is your perception, then that is not my intent. It is about knowing your conditions as you progress. If on a line and you are making your way to the fire and encounter such conditions, it is something you can do to prevent the gases from combusting as you make your way to the fire.
If venting is done right, there wouldn't even be a worry to use such a technique, because gases should be exiting out the vent and not over you. I'm not advocating sitting inside a structure waiting for vent to be completed prior to opening up on a fire. I'm not advocating one has to be sitting on top of the seat of the fire to put it out, but I am advocating one knows where the fire is and can hit it before just spraying water all over.
In many situations out there, there wouldn't be a need to worry about getting caught in such conditions, because you are either on scene before conditions can develop, or arrive after such conditions already presented. Strategy, tactics, staffing, resources, etc, etc all can play a part, so it is about looking at the whole picture, not just this one aspect.
Just to make it perfectly clear. Such conditions should not be the norm for an offensive attack. What I'm talking about here and my responses stemmed from the OP questioning signs of flashover or backdraft from inside, is about techniques that can be done to prevent the fire from intensifying due to heated gases in smoke combusting before you even get to a fire. This is why we train and COORDINATE our responses, to get the best, fastest, and safest mitigation to the problem.
Going back to my original response to the OP, I advocated looking at things from the outside first, doing a good sizeup, getting as much information BEFORE even entering the structure, so one doesn't have to worry of providing first hand accounts of surviving a flashover, if they are lucky enough to live through it. Like a MAYDAY, it is important to train on and prepare if the situation were to occur, however, the best results are not having to employ them.
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Makes sense to me now, be proactive and not reactive, why horizontal vs verticle venting?
Steve,
Horizontal is much faster and can be done with limited personnel. It involves essentially busting out the right windows to vent gases quickly. Vert vent can be more time consuming and utilizes more resources. In many cases, the fire can be extinguished before vert vent is even completed.
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