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  1. #26
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    George: please correct me if I'm off-base; there is already discussion that there were no furnishings in this room, so how could flashover cause articles to hit their ignition temperatures if the room was empty?

    I don't know. I suppose you could have flashover in a room with no furnishings if the initial fire was burning inefficiently and was large enough to fill the room with lots of superheated gases. My initial guess (underline, bold, italics...guess) would have to be that there were wall or ceiling finishings that began to burn.

    I am staying on the sidelines on this one until I hear some facts from the investigation. So far, there is not one thing that we shoul dbe commenting on, other than the fact that it appears they are doing a complete investigation.

  2. #27
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    For information - here was my original post Dave refers to above - 'It is a sad fact that the vast majority of firefighters and training officers still have little or no realistic appreciation of how fire gases form, transport and ignite under a wide range of conditions encountered in structural firefighting. When firefighters enter a burning structure, be it a real fire or a 'training' burn, it is essential that they understand how fire gases are able to behave like petrol vapors! Would they advance into a structure that they knew was swamped with petrol fumes?

    What is a flashover? or a backdraft? or a smoke explosion? or a forward-induced explosion? or a flash-fire? where are you likely to encounter high-velocity fire gases? Can ventilation cause a flashover or is this a backdraft? What is the effect of creating a vent opening behind the advancing firefighters?

    These are all questions that every firefighter and training officer should know the answers to! Do you?

    The behavior of fires can only be taught safely and effectively in purpose-built fire behavior 'simulators' (container style) and even then, a basic introduction session is far from sufficient. Multi-compartment, observation and attack units are needed to provide the depth of knowledge required to understand how fire gases form and transport and tactical venting actions should be used to demonstrate likely effects at real fires, taking into account the effect of creating/widening ventilation parameters.

    Firefighters will continue to die in fires until we provide them with this knowledge - fire gas formation, transport and potential for ignition.

    George was the only one to reply to that post......

    I have to say that you most certainly can achieve 'flashover' (of a sort) or NFPAs 'Rapid Fire Progress' with just Pallets and Hay as fuel, where the fire becomes ventilation restricted (ie; not enough air in the compartment to support complete combustion). I am notr suggesting this is what happened in Florida as I don't have the facts - but it can happen! The smoke can ignite in a flash-fire and create circumstances similar to 'flashover' - see http://www.firetactics.com/FLASHOVER.htm in particular.

    We have used exactly these two fuels to achieve controlled burns in fire simulators (containers) and demonstrated repeated ignitions of the fire gases in a 'safe' environment - no firefighter has EVER died in a european container burn.

    As George said - don't rule out any wall or ceiling linings that may well increase the potential for such an event to occur. Such ignitions may even initiate in compartments (rooms) adjacent to the fire-room itself.....NOTE THAT POINT! This really does take firefighters by surprise.

    Learn from this guys and stay safe......PLEASE!

  3. #28
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    Question Re: No speculation, no conversation

    Originally posted by lilsisterosceol
    Everything has been sealed tight and people who talk have been threatened with loss of employment so if you don't speculate or try to figure it out, you might as well shut down this thread.

    Pallets and Bales of hay???? I wonder how much was used? The statement that they were going to have a big burn would suggest that possibly someone over did? You are the experts, I just have my ears open.

    I have a question for you. This training facility is in a heavily wooded area. The initial report by the press, (reliable or not) was that the trees and brush outside the window caught fire. Would that make any difference in the equation?
    That would be as a result of heat or flame escaping from openings in the structure when the "flashover" occurred...and probably had nothing to do with the initial event. The exterior fuels (trees, shrubs) would not be a factor here.

    I'm curious as to why you state that this "has been sealed tight" and what relationship you have with Osceola County Fire...as denoted by your lilsisterosceol forum name. Is there some concerted effort at a coverup there?
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  4. #29
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    NJFFS posted: I'm curious as to why you state that this "has been sealed tight"

    Lilsister posted:
    I suppose because of my relationship with OCFR the press, media if you will have been contacting me. Since I am as I said, "Joe/Josphine Taxpayer". I would guess that is fairly hard up on there part? Pardon the slang. Perhaps I am the man/women about town, I don't know, it is difficult for me to explain who I am because folks just don't believe me.

    NJFFS posted:
    and what relationship you have with Osceola County Fire...as denoted by your lilsisterosceol forum name.

    Lilsister posted:
    I am Littlesister to Local 3284

    NJFFS posted:
    Is there some concerted effort at a coverup there?

    Lilsister posted:
    Not so much a coverup. Perhaps and my heart is sinking as I say this, we have a Lairdsville as someone suggested earlier.

    Last report I have read: While there has been some speculation on how the firefighters may have been critically injured in the one-stroy abandoned building donated for fire training, the state fire marshal's office said Friday that the investigation was still ongoing and a conclusion may not come until sometime next week.

    You are the experts, if there were no problem or issue, the report would have come out when promised which was two days after the incident. Lilsister is feeling very sick in the pitt of her stomach. Gentlemen, OCFR has been using abondoned buildings for training, for decades. The particular house they were in was used the previous week for burn training. I don't know which department used it, but I saw the fire with my very own eyes.

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    I know that they have acheived "flashover" in our local fire academy training burn building, just using pallets and hay.

    Lilsister, you know your area better than us, but there are many, many things that could change when an investigation is complete and when details will be released. They have said from the beginning that they want no mistakes.....the biggest mistake is releasing info too early, especially when it becomes inaccurate.

    I am curious as to why peoples jobs were threatened, but then they suspended the Asst Conductor in Boston that had some "verbal diarhea" after the train stopped at 2 stations before helping the heart attack victim. So maybe they are just trying to prevent the "wrong" information from getting out.

    Remebering our Brothers, and waiting for more details.......

    Dave

  6. #31
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    To Paul Grimwood....Glad to have you back...Excellent comments on this thread. Look forward to your well versed and sensible input.

    Locally.....MUM seems to be the word. I have seen no additional information since the announcement" "THE STATE FIRE MARSHALL"s OFFICE IS INVESTIGATING."
    09-11 .. 343 "All Gave Some..Some Gave ALL" God Bless..R.I.P.
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    Thumbs up Agreement & Understanding

    You are so very right in all that you say. No more speculating on my part.

    We will await the release of information from the proper authorities at the appropriate time.

    For those of you not familar with our form of government. I live in what is called an unincorporated area. Our local government is run by 5 County Commissioners, the honorables. They give direction to a County Manager who in turn gives direction to staffers. Fire Service has become too intricate and scientific to allow too much involvement from laymen and the above governing body knows nothing about Public Safety. This is strictly my own opinion and personal preference. Since all of the above work for me, I make sure my vote, my voice and my tax dollar are spent on what I believe to be the priority for my county, "Public Safety". My belief is, if more people take an interest in their safety and quit relying on their local governments to look after their welfare, fire service would be at the level it should be. It is not prudent for me to wait until I have an emergency to wonder if the response team is trained, has the appropriate apparatus, is going to respond within a standard amount of time, et.al.

    I would like to thank each of you. You have packed more information into this small thread than I have garnered in the past 3 years. Keep doing what your doing, it is a service to the world.

  8. #33
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    A couple items then to expand on George & Paul slightly

    First, I agree with George that there isn't enough specific information on this incident yet for specific comments to be made on that situation.

    Second, my gut really wants to know if there was a dropped ceiling or otherwise big void above their heads -- but that will come out in the reports.

    Hay & Pallets are undoubtly safer than petroleum-based products.

    Petroleum products are hydrocarbons. They got lots of carbon in them.

    Combustion is rapid oxidization.

    Petroleum products, unless fed through a carberator or similiar device to make the right air/fuel mix, don't burn clean do to a lack of enough oxygen to use up all that carbon.

    Wood & Hay have a lot less carbon, so they need less air to combust completely to form CO2.

    But wood & hay without enough oxygen certainly can form CO -- carbon monoxide, which is one of many unburned products of incomplete combustion we can encounter. And CO can explode and/or flashover.

    There is a lot more work, work on the scene, that must be done to say it was caused by hay & pallets creating CO causing a flashover. There's much more likely causes to rule out first (like wall board or combustible ceiling tiles hidden behind a newer ceiling).

    If in the end the only fuel source was hay & pallets then that will be good information to take for the next revision of NFPA 1483(?). No standard can protect you from every event, but we can strengthen the standards based on our experiences.

    Matt

  9. #34
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    Hay & Pallets are undoubtly safer than petroleum-based products.
    Not for nothin. but 1403 permits Class A fuels like hay and pallets. If you can't use hydrocarbon fuels (with good reason) and then they write hay and pallets out of 1403, what do you use then?

    I am not commenting on this incident!

    Flashover prevention is of far more importance than what Class A fuel you had burning. In 1403, they discuss things like ensuring enough ventilation and having a way to evac the gases in an emergency, making sure the wall coverings are removed, making sure combustible ceilings are removed, etc. Therre is alot to preparing an acquired structure for a live burn.

    Paul, I have posted on here at least three or four times that, in my opinion, many officers today are placing their people in great danger due toa lack of knowledge and understanding about the science of fire. Thanks for your insight.

  10. #35
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    You guys should read this commentary by my friend and mentor Dr. Harry Carter.

    http://www.harrycarter.com/2002/Aug_...st_4,_2002.htm

  11. #36
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    and then they write hay and pallets out of 1403, what do you use then

    I don't think we need to go that far.

    But I don't think it would be beyond reason to actually use facts and not gut feeling in running training burns -- to require heat & CO meters in place before burning that can go into alarm with extreme heat, with sudden rises in temp, or with excessive CO levels (indicating incomplete combustion). The costs I'm guessing would be competetive with building not-so-realistic burn trailers but with greater portability. (Trailers have their place, so do burn buildings. IMHO Acquired structures are much better for realistic scenarios)

    This isn't just for acquired structures, but for concrete buildings to. And it's consistent with trends in the fire service to push technology like CO meters and heat-sensing PASS alarms were we used to just guess at it.

  12. #37
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    Default The science of fire

    I am troubled by any live burn session that results in injury let alone a death of one of our brothers. Like others I will wait until more information becomes available before I comment regarding the specifics about this incident. I will, in my limited way, try to help those who read this thread understand what I understand about basic fire behavior based upon scientific observations.

    1. Fire exists in two modes; glowing/surface combustion and flaming combustion.
    2. Glowing/surface combustion fires consist of fuel, heat and oxygen in sufficient quantities. For glowing combustion to take place, at least 15% oxygen is required. Less than that, and a fire in will not be able to continue to propogate after a period of time.
    3. Flaming combustion, is a little more complex, since it involves not only those elements listed under glowing/surface combustion, but it also involves a chemical chain reaction.
    4. Flaming combustion unlike that of glowing/surface combustion requires that fuels be gaseous in nature, as our collegue Mr. Grimwood has enlightened us all. If the fuel is a solid, such as appears to be the case in OCFS incident, then the fuels must be pyrolized. (NFPA Handbook, 14th edition, pg 2-23). Liquid fuels, only need to be evaporated. Some liquid fuels will vaporize at standard temperatures and pressures such as gasoline (petrol as Mr. Grimwood likes to state). We refer to that point at which a liquid gives off sufficient vapors for a flash to occur as a liquids "flash point".
    5. But we cannot forget that when any material burns it does so in combination with oxygen. Most of the time the oxygen exists at 20.9% in air. Sometimes it is assisted with other materials such as hypochlorites, nitrates, etc. But we also must understand that oxygen need not only be present, but it must be mixed with the fuel (read vapors) in proper amounts. We know that when we adjust a carborator of an auto or lawn mower engine that if we have too much fuel and not enough air the engine won't run. It's too rich. If we have too little fuel and too much air, it won't run because it's too lean, or has insufficient fuel. But get it between its Upper Explosive Limit (UEL) and its Lower Explosive Limit (LEL) and bingo, you've got what you need, a controlled explosion inside a sealed container.
    6. During a compartment fire, we will run through a series of steps that go from incipient to free burning to smoldering, that dependent upon the stage of the fire will have differing concentrations of heat, fuel and oxygen. These levels can be different dependent upon various factors. Where you might have sufficient heat, and fuel you may lack suffcient oxygen in the upper levels for flaming combustion to occur. But beware when those free fuels (vapors) find sufficient oxygen, like at a window or door. This is what Mr. Grimwood explains to so many on his site.
    7. Let's look at only one gaseous vaporized fuel given off by any fire involving an organic material like, straw or hay. Carbon monoxide; LEL - 12.5% to UEL - 74.2%. While we all know the health affects of CO we frequently neglect the flammable component of CO, despite the fact that research as early as 1933 indicated that CO was and continues to be a major contributor to rapid fire spread. (NFPA Quarterly, Vol. 27, No. 2, Oct. 33).

    Understand that this is not a discussion to whack those in Florida, but simply an educational opportunity to those who read this. Understanding basic fire behavior and physical fire chemistry should be paramount in any fire fighters and officers knowledge base. NFPA several years ago produced a fire behavoir video, which is very good. Every fire fighter should see it. I believe that it was simply entitled, "Fire Behavior". I hope that I have helped in just one small way.

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    LEL - 12.5% to UEL - 74.2%. While we all know the health affects of CO we frequently neglect the flammable component of CO, despite the fact that research as early as 1933 indicated that CO was and continues to be a major contributor to rapid fire spread.

    To add just a bit, LEL is the lower explosive limit in air, i.e. 20.9% O2 @ standard temperature & pressure.

    In a fire environment you'll have less O2 which would generally increase the concentration needed to burn/explode, but at the same time much more heat which would generally lower the concentration needed to burn/explode.

    So you end up with hot gasses much more likely to burn but lacking oxygen. When O2 is found...

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    Dalmation90,
    Thanks for pointing that out. Although I believe that most of the time the reason that we may have a free burning fire in a compartment that does not light off the CO and other freed gases and products of combustion in the smoke, is that the concentration of those gases and particularly the levels of CO are so high that they are above their UEL, not below their LEL. I don't believe that the heat of the fire changes the UEL or LEL of any gas, but the heat of the fire with less oxygen makes a fire more efficient than one with less heat and the same level of oxygen. Less heat, less oxygen makes for a very inefficient burn and the production of higher levels of CO and other fire gases. The more prevalent the gases, the more likely you will achieve the necessary LEL of any gas and therefore make it easier for ignition of those gases to occur.

    This is consistent with smoke that doesn't light off until it hits a window, door or other point of ventilation. If that opening or rate of oxygen influx is higher than the rate of gases escaping from the opening, the bouyant superheated flammable gases and smoke will ignite back to the original fire. If the opening or rate of oxygen influx is less than the rate of gases escaping then the fire will continue to burn on the outside where sufficient oxygen can combine with the gases.

    George,
    I just read Harry Carters article and it is a great idea.

  15. #40
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    Once again, Dr. Carter has share with us some of his wisom and insight and has presented a very innovative idea.
    09-11 .. 343 "All Gave Some..Some Gave ALL" God Bless..R.I.P.
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  16. #41
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    CaptStan - how are you buddy? I remember a post of yours on here a year or so back that described a similar situation whereby a fire-load of 3 wood pallets totally overwhelmed the firefighter who was sent to light the fire! A page on the NIST website demonstrates how severe a fire just 5 wood pallets can create and I constantly read of firefighters who have found themselves backing away from pallet training fires due to the build-up of heat.

    I try not to elaborate too deeply on fire dynamics as it tends to 'frighten' or 'bore' many firefighters. I think it may be more productive to discuss the basics of what can happen and how firefighters can practically avoid such situations.

    Whilst I am a great admirer and follower of Dr. Carter's work I cannot agree with his proposal of MFTs (Mobile Fire Trainers). The use of gas-fired facilities fails to offer any realism at all to firefighters and 'fire behavior' cannot be effectively taught as such. I would think the siting of carbonaceous simulator programs, shared between several departments/areas, would be far more effective. Note I say 'programs' for a single compartment observation simulator alone would not fulfill the needs of firefighters.

    A 'compartment' trainer - an 'attack' trainer - a 'multi-compartment' trainer and a 'window' container are four different modular (container) structures that may be used to introduce the basics of fire behavior BEFORE advances are made into aquired structures. These units are all fuelled by class A boards or pallets and offer a much more realsitic learning ground under safe conditions.

    Don't ever think the gas-fired units are the answer.
    Last edited by PaulGRIMWOOD; 08-05-2002 at 04:55 PM.

  17. #42
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    For Those of you that have not found it, here is a link to one of the stories and a news source that I am told we can follow to gain information.

    http://www.newschannel2000.com/orl/n...01-080823.html

    Paul...In the past I also have been in that situation, where a training fire ended up being a "bit more" than I orignially thought it would be due to an often overzealous "igniter" trying to help it along because it was not burning "good enough." The addition of a "little more straw" and "1 more pallett" often was enough to cause the fire to begin to roll across the ceiling and then out into the next room (an this was in a "burn building")causing temperatures to be very high, dense smoke and almost zero visibility. So yes...I have been there....done that.

    As I said, I have great respect and admiration for Dr. Carter and I do agree with his proposal. However, he does not suggest that is the "fix all" for live training problems, just one solution that would have everyone (theortically) playing on the same page. If I am correct what you are describing as an idea is very similar to the "flashover" simulators that are already in use in several jurisdictions across the nation. I also feel this is an excellent educational tool that provides a bit better understanding of fire behavior for the firefighter. The danger, excluding the unknown of course, is much less in these situation.
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  18. #43
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    Appreciate your views CaptStan and acknowledge again Dr. Carter's work. I am opposed to gas-fuelled trainers as a way of teaching fire behavior. There is NO WAY firefighters will learn a thing about how fires develop and behave in these facilities, neither is there an opportunity to experiment with venting actions. In other situations, ie; practising nozzle techniques or training for aircraft fires etc they are ideal.

    The flashover simulators provide a safe and effective opportunity to teach firefighters about fire development etc but there are two points relevant here -

    1. The systems need to be run properly and the instructors need to be top grade!

    2. The use of a single compartment observation trainer will NOT achieve the aims alone. As I said, an 'attack' unit is also required to teach door entry and line advancement techniques; a window container to teach backdraft phenomena; a multi-compartment unit to teach basic approaches and standard ops incorporating tactical venting actions etc. As well as this there should be substantial classroom input using small scale demonstrators to place emphasis on essential features of fire gas formation, transport and ignition.

    To introduce firefighters to a single burn in a single unit is only really scratching the surface here.

    I have not commented specifically on the Florida incident so far - however, I note from two different reports that the firefighters appeared to be working ahead of the nozzle as a 'search' team. I can only say (I know this happens but) firefighters who place themselves ahead of the nozzle in both real or training fires are taking one almighty risk! I don't feel such risks are worth taking in training situations....That is not criticism levelled at anyone involved in this tragedy but just words to express my feelings to firefighters who may read this who may be involved themselves in future training burns anywhere.

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    Blimy! Checking up on my terms, I came across this http://www.firetactics.com/TEC-JARGON.htm which is excellent, and sure enough it's Paul's site.

    Couple points back at AMFM, though I don't think we're far off.

    Oxygen is the limiter in heat, not fuel. Same amount of fuel with unlimited O2 will burn hotter and cleaner. Limit the O2 and you'll produce less heat AND more unburned (non completely combusted) gasses.

    The ironic thing for training is perfectly combusting fires aren't what we encounter -- if they were propane burn buildings would be realistic. Visible smoke comes from less than clean burning.

    To my mind, what I think of as a "Flashover" when nearly the entire room becomes involved at once without a change in ventilation is a result of unburned gasses reaching their auto-ignition temperature. They have to be between the LEL and UEL for that. Oxygen definitely affects the LEL/UEL (alternately it's proper to call them Lower and Upper Flammable Limits). There's a lack of 02 by the flame to ignite the gasses, but they reach the right mixture and temp throughout most of the rest of the room.

    "Backdraft" situations are definitely when you're above the UEL -- not enough oxygen but the heat is above the ignition temp. Vent to add O2 and it lights up.

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    Ohhhhhhhhhhhhhh, See what you started Pauly G. lollllll.
    A simple ex K.I.S.S. FF is going to try to kick in here.
    Flashover ocours when the heat at ceiling level builds
    and radiates down to the contents of the room and reaches its
    ignition temp and ignites, similar to putting the olive oil
    and butter saturated garlic bread to close to the broiler.
    Flash-over your low on heat , Backdraft your low on oxygen.
    So what you guys are saying is you can have a flash-over
    with out fuel, or are the unburned gases the fuel? I would
    think a fire would go into the low oxgen stage before it
    feeds on itself. Ohhh Im thinking to much .lollll

  21. #46
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    Hello again Kevin - I am all for K.I.S.S!!! (Hope the guys get the meaning we intend on this )

    Blimey Matt!! I love it when firefighters try to put fire dynamics into everyday firefighter 'talk' - the boffins would have a field day tearing us all apart In the end we are just trying to make sense of what is a complex topic....so complex that even the 'boffins' don't always agree on terminology and definitions!

    Now if this confuses you I am sorry! Flashover is a generic term we use in the fire service to describe a wide range of events. In reality both air-in-flow (ventilation) and a high Heat Release Rate (HRR) can be separately responsible for 'flashover'. A backdraft is initiated by air-inflow where O2 is in short supply and then there is 'smoke-explosion' where an ignition source is introduced to a pre-mixed 'pocket' of fire gases within their explosive range. I think everyone who is posting acknowledges these points. There are other ways such phenomena may occur - note 'forward-induced-explosions' and 'flash-backs' etc. There is also an effect termed 'blow-torching' that may be caused by wind or PPV airflows etc. The NFPA group all of these under a heading termed 'rapid fire progress' as it is usually impossible to differentiate between events on the fireground.

    I think it is important for the firefighter and training officer to recognise these basic points -

    1. Any form of rapid fire progress may occur slowly (with a whoosh) or rapidly (with a bang), with resulting pressure waves that may break windows or push walls out.

    2. Warning signs for both backdraft and flashover are well documented in training manuals and should be observed.

    3. Training manuals suggest both venting actions and PPV may help to prevent 'flashovers' and backdrafts - they often fail to inform that such actions may also CAUSE the same!

    4. Little attention is paid to fire gases mixing, forming and transporting in the structure - providing potential 'pockets' of pre-mixed gases in their explosive range. These 'pockets' may exist in the fire room itself; in the overhead (esp. high ceilings); in adjacent rooms or even rooms some way away from the fire - possibly even on the floors above; in cupboards; hallways etc etc. If an ignition source is introduced a resulting smoke explosion may occur.

    5. Any vent opening made behind firefighters is most likely to 'pull' heat and flames in the overhead towards advancing crews. A vent opening made to the side of firefighters as they advance MAY end up BEHIND them! Also, the entry doorway is a typically large vent opening!

    6. Water-fog most certainly CAN be used to COOL or/and INERT dangerous fire gases in the overhead, or in adjacent areas. Likewise, straight streams are also likely to cool any potential for flashover. However, there will be occasions where NOTHING will prevent rapid fire progress - but remember, (ball park figure) about 90 percent of 'rapid fire progress' is initiated by OUR ACTIONS! Maybe a window too many was popped or a constant fog pattern 'pushed' some fire into the gases in the overhead or something. Look closely at NIOSH reports and try to analyse the 'action' that may have initiated a 'flashover' etc. This is how we learn and you never stop learning in this game!

    K.I.S.S. said Kevin!!! lol


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    That pretty much summed up my question in the KISS method as to what is in smoke.

    One concern that I see involved in fire ground or at a training excersise is the time factor. Between the conditions of the inside by ( interior teams ) and what is being seen and done on the outside outside ( sector's or IC ). It only takes a minute and then we lose Brother's and Sister's and while keeping in mind that first 10-15 minutes we may even make grabs and knowing that those 10-15 will dictate the next 60 minutes or the next 10 hours.
    Thats what I see as being just as an important issue.

    FTM, PTB, RFB
    FDNY 343
    Last edited by FF.1205; 08-06-2002 at 06:00 PM.

  23. #48
    District Chief
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    Question

    Paul.....

    What is your opinion or your thoughts (forgive me if I missed them elsewhere) on rook top openings for ventilation and their ability to assist in the control of potential backdraft situations and flashover. Specifically, if you open the roof of an acquired structure to afford ventilation will that assist in taming the beast or not? Point in question....looking at photographs both ground level and aerial of the building in question in Osceola County, there are NOT any apparent roof openings and the description of the building I believe was one that had only one window (1)...{??correct}...


    Posted by Ten 8_Ten 19
    I watched the interview (linked on the FH main page) with an LT that was on another team in this burn. I found it interesting that they were advancing into a concrete block structure with one window with high heat and zero visibility.
    Hmmmm..makes one wonder????
    Last edited by captstanm1; 08-06-2002 at 09:29 PM.
    09-11 .. 343 "All Gave Some..Some Gave ALL" God Bless..R.I.P.
    ------------------------------
    IACOJ Minister of Southern Comfort
    "Purple Hydrant" Recipient (3 Times)
    BMI Investigator
    ------------------------------
    The comments, opinions, and positions expressed here are mine. They are expressed respectfully, in the spirit of safety and progress. They do not reflect the opinions or positions of my employer or my department.

  24. #49
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    FF1205 sure basic line placement and initial venting
    can make the difference in the first 5 min at a job to
    keep suprises to a minimum. It takes training , discipline
    and teamwork .Fire only gets larger before it consumes all
    the fuel or the FD intervenes. Its the point were we intervene
    that takes knowledge of being able to read the signs of smoke
    heat,flame to help us know what stage the fire is in which
    would dictate are actions. No matter what type of fire ground
    you are on always stay focused to the job at hand and it can
    help to keep suprises to a minimum . Anticpate the worst.
    Fire is never routine or totaly predictable. Stay focused.

    Capstanm1 your post poped in while I was commenting on
    FF1205 thoughts so Ill throw in and compare notes with
    Paul. Definitly as far as preventing Backdraft and directing
    the horizontal spread of heat to control Flashover opening
    the roof is the safest way to go. If only all fire buildings
    were 1 story high with a flip top on the roof it would make
    the job nice and simple.

  25. #50
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    I am not a proponent of cutting holes in roofs to ventilate and it is rarely practised by UK firefighters. However, I know Kevin (& others) have extensive experience in this strategy and I would most certainly acknowledge its benefits. I was in NY in 1979? when they lost six firefighters off a roof and that left a deep impression on me. I wonder sometimes if we should be in a defensive mode at this stage of fire ops? If a roof is unsafe then neither should there anyone on it or under it! The difficulty comes in assessing a roof's stability and you often have to be on top to know for sure. I remember experienced FDNY firefighters explaining to me how they would feel the sponginess in a roof beneath their feet and still work on it.....they knew what they were doing alright but it made me shudder!

    I second Kevin's point - anticipate the worst scenario at every fire and you work 'back' from that point!

    Hey - I will be in Cyprus (for two weeks) in 7 hours!!! Adios bros

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