1. #1
    LT334
    Firehouse.com Guest

    Post Ventalation question

    I have a question I'm hoping someone can help me with. My dpt. recently responded to a residential structure fire, and were on scene within 3 min. As the first engine arrived a single story wood framed older house of common construction was found to have smoke comming from the attic window. The homeowner had been doing roof work and accidently cought it on fire. There was minimal flame at the attic window at the time. In an attempt to keep the fire in the attic, a positive pressure fan was set up at the front door. Almost imediatly the flame in the attic intensified to a point of ingulfing the attic within a few min. Was this proper proceedure? Should the living space have been ventalated somewhere else first? Maybe , oir maybe it was a fluke.we should have use natural ventalation, or maybe it was a fluke. What would your dpt. have done? Thanks

  2. #2
    ADSN/WFLD
    Firehouse.com Guest

    Post

    That's why I don't like the PPV fan for fire attack. If a PPV fan is utilized without lines hitting the fire the fire will intensify, it may spread to areas of the building that are uninvolved or right into void spaces within the structure.

    I would have started to throw salvage covers while the crew started to attack the fire from the scuttle or attic stairs. Venting can be done by opening the roof (depending on how much of the deck is damaged) Depending on the progress you may have to pull some ceiling.

    While not something you see every day this fire shouldn't have been that much of a problem. As long as your department learned some lessons and no one got hurt then it didn't go that badly. It was a learning experience.

    Remember you didn't start the fire and it wasn't your house.

    Stay safe & learn

  3. #3
    Staylow
    Firehouse.com Guest

    Post

    I have to admit that I have not supported the positive pressure ventilation issue because I think it to be a waste of time and manpower more than a helpful solution to problems. This story helps me to reaffirm those beliefs, but again, it is only my opinion. It sounds like you stoked the fire by not letting the added air escape through some type of vent hole in the roof. I'm sure there are others that will be able to let you know what exactly went wrong, and how you can learn from the situation.

    As an alternative, maybe the guy who was setting up the fan could have pulled the ceiling for the engine crew, while another two guys made a well placed hole over the involved area of the attic for ventilation. Just my two cents.

    Stay Safe!


  4. #4
    Mike DeVuono
    Firehouse.com Guest

    Post

    By using PPV in the attic w/o ventilation all you did was fill the attic with much needed oxygen. As was already said, this could've been a quick knock with one line. Stay safe


    ------------------
    Mike DeVuono

    "There are few atheists inside a burning building."

    These are my opinions and not those of my department.

  5. #5
    LT334
    Firehouse.com Guest

    Post

    That's kind of what i've been wondering myself. I think we caused more harm than good. By the way, the guy lost his house, and unfortnatly, I dont think any lessons were learned.

  6. #6
    Iona6
    Firehouse.com Guest

    Post

    While its too easy to second guess strategy without all the facts, it seems that there was no need for assisted ventilation at this fire. Fire burns up faster than it burns down. If the attic window was already compromised, the opening of the attic scuttle should have been enough to provide for natural ventilation and hold the fire to one side of the attic. Wind blowing the fire through the attic or some other condition would call for PPV to hold the fire to the attic. Be gentle. first post.

  7. #7
    4iron
    Firehouse.com Guest

    Exclamation

    I've taught/advocated PPV for 15 years,when used properly,PPV is a safe productive method of ventilation.The major problem with PPV is the decision making:when and when not to use it.Just because we HAVE these high volume fans,using them on EVERY fire may result in losing the structure.PPV is just another tool.Attic fires still need to be opened at the highest point/above the fire,in most cases.
    With PPV:always open the 'exhaust' hole first,then the 'intake'.

  8. #8
    Bob Snyder
    Firehouse.com Guest

    Lightbulb

    Let me start out by saying that I've never been a "fan" of positive pressure ventilation, no pun intended. (Ouch! That hurt...just by typing it.)

    Anyway,

    You didn't really say whether the attic window was open, or you could just see flames on the other side of the window, so I'll cover both...

    If the fire had vented through the window and the attic was the only part of the house involved, then that window would probably have given you adequate ventilation. Get in there and knock that fire down.

    If the window was closed, how about sending a hose team to the attic entrance, then breaking the window from the outside before they enter? That should give them someplace to push the heat/smoke/gasses, while producing minimal damage beyond that caused by the fire itself. If they wait outside he (closed) attic door until you break the window, they should be protected from an unexpected flash or flare-up and have time to react to the situation. If you don't have the manpower available to throw a ladder to break the window, then a rock, brick, or some other heavy object of that sort will do (I'm not kidding...I've done this).

    Of course, if you come upon a similar situation and see clear signs of impending backdraft or flashover from the get-go, it's time to get that roof open before you put anybody in or near that attic.


    Just my opinion. Hope this helps.

  9. #9
    FireLt1951
    Firehouse.com Guest

    Post

    Lt334,sounds like you may have had 2 problems.Although I wasn't there,I will give it my best guess.Remember 2 things. One,always make sure that your ventilation hole is at least 100% as large as your PPV entry and that your fan will cover the whole entryway,I actually prefer 150% as large.Always try to shut all interior doors leading to the entrance of the attic or room of origin.It sounds as though your opening wasn't large enough and no interior doors were closed to allow the movement of air up into the attic.Remember this is just a guess,I wasn't there to notice if any of this was done.PPV does work well when it's done correctly.The timing of all these is important also.If the timing isn't right you will get exactly what you had.A high volume air feed to the fire.

    [This message has been edited by FireLt1951 (edited 02-19-2001).]

    [This message has been edited by FireLt1951 (edited 02-19-2001).]

  10. #10
    FF/EMTSPANBAUER
    Firehouse.com Guest

    Post

    I hate to nail the carpet to the floor, but I will ad my 2 cents.

    PPV can be a great tool if used properly. The biggest problem is that ventilation itself really isn't gone over in essentials, as in depth as it needs to be. The object of PPV is to provide a pressured draft of air current to control the fire in an small area.
    An attic, whether it may be as small as a **** loft, or a full open floor, is a very easy place for fire to spread rapidly. Controlling a fire in an attic, can prove to be a very difficult task without the use of quick ventilation.

    My advice is to work with your manpower situation as the emergency provides. If you have the extra compliment, set up a ventilation team to work hand-in-hand with fire attack. This way, the order for ventilation to begin, can be given at the exact moment water hits the fire.

    If however you are running short on manpower, natural or hydraulic ventilation can be just as effective.

    ------------------
    --Stay Safe, and Remember our Fallen Brothers and Sisters.

    John Spanbauer
    Firefighter / EMT-B / Dispatcher

  11. #11
    eyecue
    Firehouse.com Guest

    Post

    Hoselines need to be in place and charged before the fan is started. The major advantage to PPV is provide fresh air to the hose crews or any trapped occupants. It will cause the fire to intensify. Since there was no life risks in this house, it would have been better to advance the lines into the house and start an attack prior to any ventilation. Ventilation in this case would have been only used if the hose crews reported loss of visibility or untenable conditions.

  12. #12
    HallwaySledge
    Firehouse.com Guest

    Thumbs down

    LT334, I can't really offer any more than any of the other posts that have already been made. In the area I work the PPV fan is used for two things; throwing through large picture windows to achieve horizontal ventilation , or to clear out the interior atmosphere AFTER extinguishment and inspection for communication and/or hidden fire. Remember your basic first-on-scene responsibilities; what type of building do you have? You said you had an older wood-frame building with an attic window. To me this suggests a Victorian style home with either a very large, uncompartmented attic or an attic living space. Plenty of void spaces and room for the fire to move around. Second, location and extent of the fire. You said you knw where the fire was becasue of the knowledge of the roof work and seeing flame through the attic window. Furthermore, you stated that the visible flame was minimal. Third, life safety hazard. You must have been met by a homeowner or contractor to be notified of how the fire began i.e. the roof work. So either the homeowner or the contractor should have been able to at least give youa very reliable answer as to whether or not someone was still inside. Fourth, correct line selection and positioning. Sounds to me like an 1 /34 would have done fine, initially. Once that line was stretched and in position, and charged, then ventilation operations could have been completed. In this case I think that a vent hole in the peak of the roof would have been the best choice followed by or in addition to a roof man breaking out that attic window with a pike. This would have aided in cooling the attic your attack team was about to enter and started to clear out the environment so you could see. If your staffing wouldn't allow that many available personnel imediately, once your Engineer got you water he could have taken a pike and vented that window himself.Again, I wasn't there and don't know all the circumstances, but, I think this is a learning experience for you and your department.

  13. #13
    BFD847
    Firehouse.com Guest

    Post

    Originally posted by 4iron:
    I've taught/advocated PPV for 15 years,when used properly,PPV is a safe productive method of ventilation.The major problem with PPV is the decision making:when and when not to use it.Just because we HAVE these high volume fans,using them on EVERY fire may result in losing the structure.PPV is just another tool.Attic fires still need to be opened at the highest point/above the fire,in most cases.
    With PPV:always open the 'exhaust' hole first,then the 'intake'.
    Well said.
    I love PPV. Works great with minimal man power. Has to be used correctly however.
    Sounds like you were pretty sure of the location on your fire. I think I would have sent my 1 3/4 in and used the window for the initial. Hard to say without being there. Don't forget one thing may not always work. Don't be afraid to re-group and try another tactic.


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