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  1. #26
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    Quote Originally Posted by Whocares View Post
    Do you guys who use fans send men to the roof or do you use horizontal exclusively? I have never used it and never understood the need.
    W do not vent the attic unless needed. If the fire has not reached the attack no sense in pushing or pulling it there.

    We do vertical vent when needed or do a trench cut as a last ditch effort to at least save part of the roof.

    My experience though is that PPV does not work as well with the attic ventilation. You have to be specific on the situation of when to us PPA when it is in the attic.

    FYI WE have Ramfans 36000 CFM

  2. #27
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    Quote Originally Posted by Whocares View Post
    Do you guys who use fans send men to the roof or do you use horizontal exclusively? I have never used it and never understood the need.
    You make a valid point, you go with what you're used to. However, in our region, we don't see the need for vertical ventilation. Why put your guys up on a roof, above a fire, difficult walking/moving positions, longer set up time etc when you can do horizontal faster, easier, and in some cases more efficiently?

    The key, though, is we practice both and are prepared to do either depending on the situation that presents itself. IMHO, too many departments ONLY do one or the other so are therefore unfamiliar with the other way of doing it. Being more efficient at one is fine, but being dead set against the other and failing to see the benefits of it is unacceptable.

  3. #28
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    Cool Ppa

    I learned PPA when I was still really Green and feel very comfortable with it's use. Both Departments that I have worked shift work for (Career and Paid-Call/Limited Term) use PPA and teach it's use. I understand and caution using it on "Balloon Type Construction" unless you are able to first punch and expose the inside of the wall above your Fire Floor and have a hoseline charged and ready if you are going to use it. Since, if you have fire that is either in the wall or going to spread into the wall it's gonna increase in size and fire in the wall unchecked is "muy mal....."

    Or...... Use that second hoseline to help put the fire out..... Fire out; no problem.

    As far as using PPA on attic fires, I've used it and found that it can be effective. However, how we did it was we opened the attic using the scuttle hatch, laddered the hatch, charged hoseline and then pulled the attic vents open on the end of the house. We then treat it like a confined room fire and use short bursts of water. If the attic vents don't provide enough airflow(you'll know this by training with the building types in your City/County/State/Area), then have the Truck Company open the roof. The way we used it may not work for you, so TRAIN, TRAIN, TRAIN.....

    It's just like all the other tools we keep in our Toolbox; Train with it, Tweak it to work for you (if that is possible), Train on it again, Ensure that all Members are comfortable and know it's limitations and then Implement the Tactic as appropriate (written SOGs/SOPs).

    This is just my .02..... Take it as you will.....
    "Be LOUD, Be PROUD..... It just might save your can someday when goin' through an intersection!!!!!"

    Life on the Truck (Quint) is good.....

    Eat til you're sleepy..... Sleep til you're hungry..... And repeat.....

  4. #29
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    It has it place. You have to be ready for the fire to show it self in a hurry. Once you forcibly add air to a fire. With the application of TIC's I don't feel it is neccesary anymore. You can now find the fire without potentially making it bigger.
    David DeCant
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    Barrington, New Jersey
    A paycheck doesn't make you a professional.

  5. #30
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    Outlet/Inlet ratio is of utmost importance when applying PPA. Many times when PPA goes wrong it is due to an inadequate exhaust opening. Studies show that when using positive pressure , the exhaust outlet should be TWO to THREE times larger than the inlet opening. A quick survey of my own departments members were unaware of this and believed the exact opposite. Perhaps this is because when using NATURAL ventilation (no use of fans) then yes, the exhaust opening should be smaller than the inlet opening.

    An inadequate exhaust opening when using PPA will definitely cause interior conditions to worsen. More air turbulence is created causing fresh air to mix in with the heated gases and pyrolizate which can lead to an increase in flaming combustion and the possibility of and extreme fire behavior event. Even worse, if there is no exhaust opening or the opening is very small, smoke and flames could push out of the inlet opening. So next time you use PPA, open up a big window for an exhaust opening or take out a small window and expand the dimensions with saws.

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    Anyone using CAFS with PPA?

    One of the theory/benefits of CAFS bubble is that the draft of the fire will suck the tiny little water bubbles out of the air and into the seat of the fire. "Perhaps" with the force of the stream end up with exterior attack. PPA is going to change the airflow and bubbles may not go where they otherwise might.

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    Quote Originally Posted by Whocares View Post
    Do you guys who use fans send men to the roof or do you use horizontal exclusively? I have never used it and never understood the need.
    Depending on the situation, we have. However, the majority of the time we do only horizontal.

    I don't know what part of the country you're from, but here we're dealing the majority of our construction being light-weight. Keeping guys of the roof is a safety measure, and PPV/PPA can be more effective than vertical ventilation.

  8. #33
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    Quote Originally Posted by neiowa View Post
    Anyone using CAFS with PPA?

    One of the theory/benefits of CAFS bubble is that the draft of the fire will suck the tiny little water bubbles out of the air and into the seat of the fire. "Perhaps" with the force of the stream end up with exterior attack. PPA is going to change the airflow and bubbles may not go where they otherwise might.
    I would think it would work fine with CAFS. Part of the theory of CAFS is the foam getting deeper into the fuel, which PPA won't affect. At the same time, if the ventilation is done properly, the vent current should draw most of the air toward the fire.

    Regardless, won't the bubbles go toward the fire with the water?

  9. #34
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    Catch,we have a "cure" for that lightweight construction roof work. T.C.
    Attached Images Attached Images  

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    Quote Originally Posted by Cappy05 View Post
    Good discussion! Nice and civil.
    that is good to see here finally... been on IACOJ for a while bc this wasn't the case over the last 6 months or so.

    anyways, i agree about the whole FD needs to be ready to impliment this. Also if you use a lot of mutual aid they NEED to be thoroughly versed too.

    One thing that can not be stressed enough is KNOW THE LOCATION through good size ups. We don't use PPA but it does have its merits.
    Originally Posted by madden01
    "and everyone is encouraged to use Plain, Spelled Out English. I thought this was covered in NIMS training."

  11. #36
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    Quote Originally Posted by Rescue101 View Post
    Catch,we have a "cure" for that lightweight construction roof work. T.C.
    not really, the set backs here are our issue. 100 feet of an aerials don't cut it when the curb to house is 60 feet, then account for the peak height, curb to center of the turntable... you just touch the roofline. We throw portables and cut when needed... normally those new "self venting roofs" have been working out for us... they just melt away when fire is under them and do the job for us.
    Originally Posted by madden01
    "and everyone is encouraged to use Plain, Spelled Out English. I thought this was covered in NIMS training."

  12. #37
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    Quote Originally Posted by Rescue101 View Post
    Catch,we have a "cure" for that lightweight construction roof work. T.C.
    In certain areas you "cure" would work great, but for most of our area it woun't work so well. When you wheel up the drive that is anywhere from 100 to 500 feet long or longer with the engine and then the tanker comes backing up the drive because there is no place to turn around at the house and both side is lined with trees at that point the ladder would be screwed. That would be one of the reasons why we don't have a ladder.

  13. #38
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    Quote Originally Posted by RFDACM02 View Post
    I know this will be the proverbial "broken record" for some here, but I think you need to look at your geographic area to determine the suitability of PPA. There are lots of factors, but the geographic locale seems to be the one that comes into play most with whether or not PPA has been found effective.

    1. Here in the Northeast, we have tons of older wood frame buildings, quite often with balloon construction. In my book balloon construction is a contraindication of PPA until you can verify the compartment is still intact. We do this by letting out the heat/smoke and entering the compartment and adjacent space to see the extent of extension. (don't forget the attic and basement in the balloon frames)

    2. In many areas of the US we have different climates. In FL or AZ the homes are often tight and use AC or heat to regulate temperature. Here in the Northeast and I suspect elsewhere windows and doors are the primary way residents control their heat. In the summer windows are open, in the winter they're closed and so are many interior doors. This leads to us being unable to control the travel of the pressurized air/smoke/heat/fire and makes it difficult to control the exhaust opening. These are again contraindications in my book.

    3. Older parts of the country seen many rebuilds/re-uses of structures so the "typical" building may be far different than it appears from the outside, again making it very difficult to control the path of pressurized heat/smoke/fire/air.

    Anytime we fail to control the path of travel of smoke/heat/fire we have a problem. This is basic ventilation. Now we arrive and add velocity to the smoke/heat/fire without control of where it's going? Where are the victims? The one significant issue is not knowing for certain if victims are between the fan and the exhaust opening? Sure we may be able to get in faster and see better, but what if we've pushed the fire toward a victim? I'm not ready to take that chance.

    I do believe PPA has merit where it meets the criteria for use, but we we seem to be seeing FD's making wholesale tactical changes based on it's use, with far less time spent ensuring the PPA is indicated.


    Here is the nail being hit on the head Brothers.

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