1. #26
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    Quote Originally Posted by fireman4949
    When used properly, which by the way is easy to learn, it saves firefighters and victims from taking unnecessary beatings from heat and smoke, and it greatly improves firefighting efforts and allows for quicker extinguishment, better search conditions and a much faster return to more tenable conditions for all involved.

    Kevin
    Amen, Brother! Couldn't agree more..... But I also agree with VinnieB....PPV is not suited for all situations. City department with 3-4-5 story walkups, multiple occupancy dwellings, different construction styles, etc. will use very different ventilation tactics than their suburban or rural counterparts.

    Balloon construction? Don't have it around here....I can probably count on two hands the number of two story houses we have in our area, and very few of them are old homes. Our common structure fire is the single family dwelling, one story, 1,000 to 2,000 sq. foot living area. For us, PPV works very well.

    It's a manageable sized building...set the PPV in the door and as the smoke clears out, it will take the hose team only seconds to locate the seat of the fire and make a knockdown. That's the key...Yes, PPV will cause the fire to flare up a bit, but you're on it in seconds and it doesn't have a chance to take off. I can imagine, though, that if you pressurize a building and you have to walk up 4 floors, force entry into and search several apartments, then yeah, the fire would have a chance to take off on you.

    We have used it with great success for about 15 years now, and are comfortable with how and when to use it. I have seen other departments attempt to use it improperly and either have ineffective or negative results, because they don't understand its use.

    I recall going to a fire with a neighboring department years ago, when everyone was just getting into PPV. They bought a fan but didn't bother to find out how to use it properly. They put it backwards in the doorway to draw the smoke out of the building, like they were used to doing with their old electric ventilation fans

    Obviously this is a rather extreme example of using a PPV fan wrong, but improper placement, starting ventilation before the hose team is ready to enter, or trying to pressurize a building that already has multiple or large vents open (making it impossible to create pressure), are all examples of improper tactics in using PPV.

    When used correctly, in the appropriate situations, PPV is indeed an excellent tool and makes conditions much more tenable for your interior crews.
    Chief Dwayne LeBlanc
    Paincourtville Volunteer Fire Department
    Paincourtville, LA

    "I have a dream. It's not a big dream, it's just a little dream. My dream and I hope you don't find this too crazy is that I would like the people of this community to feel that if, God forbid, there were a fire, calling the fire department would actually be a wise thing to do. You can't have people, if their houses are burning down, saying, 'Whatever you do, don't call the fire department!' That would be bad."
    C.D. Bales, "Roxanne"

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    I've noticed that it seems the departments that are really big into PPV and say it works greata are all "new" cities where the construction is much less problematic than the northeast.

    Many places in FL, CA, NM where the house is always tight due to the air conditioning. Fewer balloon framed construction houses. Less plaster on lathe walls and rough sawn strucural members.

    In the Northeast we have tons of 100-200 year old houses with dry decaying wood frames, tons of combustible voids, and poor compartment containment (palster vs. sheetrock). I just flat out do not believe the research shows that PPV can keep fire out of the voids when you cannot tell where the entrances to them are. Maybe teen age Johnny punched a hole in his bedroom wall and it's covered with Britney Spears poster? Obviously most new construction is better compartmentized and may benefit from a proper PPV/PPA tactic but even with PPV it will take another 100 years to burn down the existing old houses.

    In 20 years I've seen many places take a stab at PPV/PPA. We have and relagated it to an after knockdown ventilation tool, which rarely works as intended because of the traditional truck work we've done before knockdown. Other places I've watched burn down a house for a standard room and contents fire. I agree with whoever stated before that PPV is not as fast. Unless you have extra personnel assigned to this task on arrival (new staffing tool?) a standard company working to get the first line in cannot lose two ffers to retrieve a fan and still get in as quick.

    Again as previously stated:
    1. How do you know that the victims are not between the point of entry and the exhaust?
    2. How does PPV pressurize the space and not push fire into voids, when you ahve no idea where the voids may be open to the fire area?
    3. What happens if its 90 degrees and the AC is out so the house has all the windows open? Assign the truck to close them?
    4. How are you sure there is no doors closed or obstructions in the exhaust path between the fire and the vent opeing? Only vent the fire room? What if its and interior space?
    5. How about an unrecognized cellar fire? Will the PPV cause a Venturi affect and suck the fire up? Saw this happen and the room and contents ended up a total loss.
    6. What if the fire is actaully in the walls and all you have is a heavy smoke condition on arrival?

    There are too many variables that cannot be known on arrival. JMHO

  3. #28
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    Quote Originally Posted by RFDACM

    1. How do you know that the victims are not between the point of entry and the exhaust? Simple for us. If they are not ALL standing outside and clearly tell us they are all out we won't use PPV initially. This is a single family dwelling of course.
    2. How does PPV pressurize the space and not push fire into voids, when you ahve no idea where the voids may be open to the fire area? This can happen, and does at times. It is VERY important that if you use PPV in the attack mode that the line be charges, at the entry point and ready to go in before the fan is used. We have not had that problem here...yet.
    3. What happens if its 90 degrees and the AC is out so the house has all the windows open? Assign the truck to close them? Nope, anymore than if a roof job was being done you would reshingle before opening the roof. If the wndows are all open natural venting is underway so why mess with it? PPV is a tool for us, not something that gets used without thought and planning.
    4. How are you sure there is no doors closed or obstructions in the exhaust path between the fire and the vent opeing? Only vent the fire room? What if its and interior space? Again if it isn't appropriate for that fire DON'T USE IT. Even if the doors are closed the worst that happens is any smoke in the building is pushed to a remote area while you advance to the burn room. The window would get popped before you open the door so when you did the smoke and heat are forced out.
    5. How about an unrecognized cellar fire? Will the PPV cause a Venturi affect and suck the fire up? Saw this happen and the room and contents ended up a total loss. Again, tatctically like any other ventilation technique it has to be done where the fire is. If you don't know where the fire is PPV may not be the best choice. I have successfully vented basement fires with PPV.
    6. What if the fire is actaully in the walls and all you have is a heavy smoke condition on arrival? Again for us if we can't locate the spot we believe the fire is we won't start the fan. This scenario could be made worse by any type of venting done wrong.

    There are too many variables that cannot be known on arrival. JMHO
    It is a tool, among many ventilation tools, that has a place. Is it always the answer? Hell no. But at times it is the answer and at times it is adamantly the wrong answer.

    FyredUp

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    Fyred Up: BINGO!! All of your answers are exactly appropriate for the use of PPV, but the intent of the Fire Chief magazine article is to debunk any myths and say its ok to use anytime. From what your answers are, your experience is like ours. Not an end all, in fact more of an after initial attack tool. I would say that 90% of our strucutre fires fit one of the 6 scenario's I presented. Really if you read your answers they defend NOT USING PPV. Considering the actual indicators of when you or I might use PPV at the initial attack, I'd rather have the compartment space the stupid fan takes up.

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    We use PPV. It can be a great tool. But with emphasis on CAN BE. The right situation where the path to vent is unobstructed (closed doors) and the fire is near the vent hole. Also no victims trapped. The problem is to use it correctly you really need to enter/search/find the fire/open doors. By now you should have controlled the fire anyway and if you can't you sure don't want to pump in pressurized air.
    With all these variables I would prefer it stay on the truck. Or better yet, to dry the apparatus floor.

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    It seems to me that the posts for and against are pretty indicative of the areas represented by the different posters. Dave1983 and fireman4949 are both from Florida and seem to agree on the intelligent use of PPV/PPA. dmleblanc from LA seems to echo the ideas.

    Guys in the NE seem to be dead set against the entire thing and I can respect that.

    The types of construction found in different areas will call for differing tactics. I do not agree with the FH article's slant toward the PPV/PPA being the be-all, end-all tactic. The use will be determined by knowing the building that you are entering (Mr. Brannigan's wise words live on).

    Intelligent use of YOUR departments tactics is what is going to keep you and your brothers safe.
    Stupid People.......Providing Job Security to Public Safety Professionals for ........forever

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