Leader

Collapse

Announcement

Collapse
No announcement yet.

Positive Pressure Attack (PPA)

Collapse
This topic is closed.
X
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #31
    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.

    Comment


    • #32
      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.

      Comment


      • #33
        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?

        Comment


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

          Comment


          • #35
            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."

            Comment


            • #36
              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."

              Comment


              • #37
                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.

                Comment


                • #38
                  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.

                  Comment

                  300x600 Ad Unit (In-View)

                  Collapse

                  Upper 300x250

                  Collapse

                  Taboola

                  Collapse

                  Leader

                  Collapse
                  Working...
                  X