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    Lewiston2FF
    Forum Member

  • Lewiston2Capt
    replied
    Originally posted by bpevans
    Hey Cap,
    You are not being ignored. Depending on the situation, conserving water can be a losing proposition that just delays the inevitable - everything gets consumed as UsingAllHands pointed out.

    We shuttle water as well and conserving water is a deep rooted belief. It is never taught, but I think is a natural (though erroneous) conclusion that people reach. Also, we get in the habit of using a particular attack method and don't look at other methods that may be more effective. The situation where I see water conservation practiced erroneously is on a well involved fire that has self-vented.

    If dumping 1000gpm of water on a well involved fire can kill it, just leaving hot spots to go contend with, then do it. Even if the sustained water supply is a few minutes away, you've killed the fire. However, if you just apply 100-200gpm on this same fire you aren't killing it - you may slow its growth, but it's still growing.

    FFs using shuttled water ought to develop expertise beyond the basics in size-up, pump ops, hose ops, fire tactics, and fire behavior due to the potentially limited water supply.
    Essentially we are saying the same thing: If you can put it out, if not control the damage until you have enough water to put it out. And, you are right it does require some additional expertise to know how to fight fires with a potentially limited water supply. I think that if there is any doubt in the mind of the officer whether or not they will be able to extinguish the fire with the amount of water on hand they should use the most efficient method to make the most progress toward that end. It may be indirect fog, it could be find the fire and dump as much on it as you can.

    Please forgive me sometimes I cant express myself all that well when I am typing.

    Leave a comment:

  • bpevans
    MembersZone Subscriber

  • bpevans
    replied
    Hey Cap,
    You are not being ignored. Depending on the situation, conserving water can be a losing proposition that just delays the inevitable - everything gets consumed as UsingAllHands pointed out.

    We shuttle water as well and conserving water is a deep rooted belief. It is never taught, but I think is a natural (though erroneous) conclusion that people reach. Also, we get in the habit of using a particular attack method and don't look at other methods that may be more effective. The situation where I see water conservation practiced erroneously is on a well involved fire that has self-vented.

    If dumping 1000gpm of water on a well involved fire can kill it, just leaving hot spots to go contend with, then do it. Even if the sustained water supply is a few minutes away, you've killed the fire. However, if you just apply 100-200gpm on this same fire you aren't killing it - you may slow its growth, but it's still growing.

    FFs using shuttled water ought to develop expertise beyond the basics in size-up, pump ops, hose ops, fire tactics, and fire behavior due to the potentially limited water supply.

    Leave a comment:

  • UsingAllHands
    Senior Member

  • UsingAllHands
    replied
    It's a beautiful day here...I'm going mountain biking for a little while. I'll try to clear my head and pretend I didn't read anything about indirect fog attack. I'll be daydreaming about copious amounts of water darkening down a large body of fire.

    In the meantime, Paul, I replied to your other thread and sent you a PM earlier.

    Leave a comment:

  • Lewiston2FF
    Forum Member

  • Lewiston2Capt
    replied
    Hello? Is anyone actually reading my posts or am I just so far off base that I am being ignored?
    Just checking.

    Right tool, right job.

    Leave a comment:

  • Batt18
    EuroFirefighter

  • Batt18
    replied
    For the love of God, please say you're kidding.
    Why?!!

    Leave a comment:

  • UsingAllHands
    Senior Member

  • UsingAllHands
    replied


    It could be argued equally that two 60gpm hand-lines could take out those two rooms in under 10 seconds using an indirect water-fog attack resulting in less than 20 gallons flowed in knockdown.
    For the love of God, please say you're kidding.

    Leave a comment:

  • Batt18
    EuroFirefighter

  • Batt18
    replied
    I can tell you that if you were using a 15/16" tip at 50 psi nozzle pressure on your 1-3/4" line, you'd be flowing roughly 180 GPM, so your 1000 gallons in your booster tank would last 5 to 5 and a half minutes. BUT, if the fire were just a couple of rooms, it would probobly be out in just a minute or two.
    It could be argued equally that two 60gpm hand-lines could take out those two rooms in under 10 seconds using an indirect water-fog attack resulting in less than 20 gallons flowed in knockdown.

    Leave a comment:

  • Lewiston2FF
    Forum Member

  • Lewiston2Capt
    replied
    UsingAllHands,
    While I see your point, I think I should emphasise what Scott was saying. I think you are both right. The problem with tanker relays is that if you shoot your whole water supply in tyhe first 3-5 minutes and your tanker relay isnt going to be set up for another 2-3 minutes you end up with the same problem as if you dont put enough water on the fire to begin with. The key is to put enough water on the fire to hold it until you get more water if not extinguish it completely.
    We too run a tanker relay for part of our first due that isnt hydranted, we use TFT nozzles. We tend to attempt to be mindful of our water situation so that in the event we need that water to get out we have it. Perhaps conservation wasnt the right term for Scott to use but it is pretty close to the idea.

    I hope I havent completely confused the issue, and please know I am not turning this into a SB vs. F arguement. All are good tools to keep in the firefighting tool kit.

    Leave a comment:

  • UsingAllHands
    Senior Member

  • UsingAllHands
    replied
    PUT THE FIRE OUT!

    Originally posted by ScottMA64

    Towns like ours do not have hydrants, So all of our water comes from tankers and drafting nearby water holes. Our smallest tanker has 1000gal of water and our largest has 2500. So until you can set up a supply line from a water source and if we have enough initial manpower, water conservation is a must. I don't remember the exact mathematics, but a 1 3/4 line @ 90-100psi is only going to last I believe around 6-8 minutes for 1000gal.


    Scott
    Scott:

    Why are you worried about water conservation? Is the object not to extinguish the fire? If you are putting insufficient quantities of water on the fire (less BTU's being absorbed by the water than is being generated by the buring materials) then the fire will continue to burn until such time as the fuel is all burned up.

    If you are using your water on exposures to keep the fire from spreading to nearby strucures, that is one thing. But, if you are simply applying inadequate quantites of water until you have estabished your endless water supply of tankers from other towns, you are only slowing down the inevitable (total loss of whatever is burning.)

    As far as your mathematics, the amount of water flowing depends not only on the nozzle pressure, but the orifice size, or in your case, nozzle type. Do you have adjustable gallonage, fixed gallonage, or automatic combination nozzles?

    I can tell you that if you were using a 15/16" tip at 50 psi nozzle pressure on your 1-3/4" line, you'd be flowing roughly 180 GPM, so your 1000 gallons in your booster tank would last 5 to 5 and a half minutes. BUT, if the fire were just a couple of rooms, it would probobly be out in just a minute or two.

    Depending on your nozzle, your 90-100 psi nozzle pressure might only be flowing 95 or so gallons per minute (or less!!) (If you're using 90-100 psi as your pump discharge pressure, then you're getting MUCH less water out the nozzle.) If the fire is producing more heat than that 95 gpm can absorb, the fire is either going to keep burning or grow larger. Yes, eventually, you'll either run out of water or the house will be completely burned to the ground.

    Leave a comment:

  • Batt18
    EuroFirefighter

  • Batt18
    replied
    UsingAllHands - no apology necessary bro, I understand exactly where you were coming from.

    I also understand the point you make about promoting basic fundamentals and I agree in principle. The simplest form of attacking a fire is by discharging a straight-stream directly at the base of the flames. The training issues concerning this approach are straight-forward.

    The training issues associated with fog tactics are greater. In terms of 3D tactics the training needs to be more hands-on in simulators (containers) or similar to ensure the techniques are practised to good effect. However, I do not necessarily think Scott's instructor is wrong in training firefighters to use indirect tactics - providing the training is efficient and correct.

    Direct attack - simple and basic but can still be misapplied to cause disruption of the thermal balance.

    Indirect attack - needs more training but in the right situation and if used correctly (from an exterior position) - is definitely a strategy that has uses for structural firefighting.

    3D Pulsing water-fog - needs the most time allocated to training to ensure nozzle operators are able to understand the different approaches to indirect methods. You are occupying the space and to get it wrong is not good. Quality training using the correct equipment is essential.

    My fear is for someone inexperienced like Scott (sorry to keep using you for an example) to come along, skim over Paul's site, and walk away saying, "Hey, you see, fog really is the way to go!" And then continue doing what he's doing, when what he is doing there in Massachusettes, is definately NOT what Mr. Grimwood has in mind.
    I take your point there and it should be emphasised. But Scott does seem to make the connection in his posts I think.

    Leave a comment:

  • UsingAllHands
    Senior Member

  • UsingAllHands
    replied
    bpevans: You are confusing the 2 different points I was trying to make in separate parts of this thread. I'm not saying that Pauls 3D techniques are gleaned from inexperience or confusion. Quite the contrary, Paul is obviously very well versed and educated in what he does. What I was stating came from confusion and inexperience was directed toward ScottMA64's fire instructor.

    My problem is this; and Paul, I hope you can take this as an apology for jumping down your throat earlier. Unless I am misconstruing Mr. Grimwood's work (and Paul, correct me if I'm wrong) Paul's techniques are ADVANCED. But we need to promote solid basic fundamentals (such as those taught by Fredericks) to prevent guys like Scott from fighting structural fires as if they were Navy firemen putting out a fire in an Aircraft Carrier during WWII.

    My fear is for someone inexperienced like Scott (sorry to keep using you for an example) to come along, skim over Paul's site, and walk away saying, "Hey, you see, fog really is the way to go!" And then continue doing what he's doing, when what he is doing there in Massachusettes, is definately NOT what Mr. Grimwood has in mind.

    Leave a comment:

  • blancety
    Forum Member

  • hfd66truck
    replied
    You know, there is one other issue not being discussed here. Actually 299 kinda referenced it. How many people invovled in this debate have the power to change their Departments practices and equipment. If UAH and E299 thought that 3-D was the way to go, do you think that FDNY would all the sudden switch. Maybe if could convince the Capt of the house their company might, but would that cause problems based on their SOP's.

    There will always be more than one way to do the same thing - and although one may work better than the other - it doesn't mean the first idea is wrong.

    I know in my Flashover training we discussed "penciling". I have discussed this with Paul, and it is the smoothbore way to try and cool the gases and achieve the same goal. It may not be as effective (it wasn't in traing) but it did have an effect.

    I guess my point is that there will always be the debate about the tools, tactics, helmets, and what color underwear is right. FDNY uses time tested tactics and equipment that work for them, but their box assignment has more manpower on it than my whole Department and my shift strength is the same as their 1st due engine. So what works for them, may not always be feasible for us.

    Be safe brothers...

    Dave

    Leave a comment:

  • ScottMA64
    Junior Member

  • ScottMA64
    replied
    We are trained to use both a indirect and a pulsing attack. Whether its good or bad, I guess it can be argued till the end of time. But realize this, towns like ours do not have hydrants, to us dressing a hydrant means putting a hat and coat on it. So all of our water comes from tankers and drafting nearby water holes. Our smallest tanker has 1000gal of water and our largest has 2500. So until you can set up a supply line from a water source and if we have enough initial manpower, water conservation is a must. I don't remember the exact mathematics, but a 1 3/4 line @ 90-100psi is only going to last I believe around 6-8 minutes for 1000gal.

    Again, thanks guys. I love this forum, lots of great info and an excellent bunch of people!!!!!

    Scott

    Leave a comment:

  • Batt18
    EuroFirefighter

  • Batt18
    replied
    UsingAllHands - You are right in stating that Andy Fredericks was a great contributor to the fire service, through his many articles and training aids. His work has left a lasting impression upon me. However, bpevans is also right in the points he addresses.

    'Confusion' in firefighting tactics arises because of 'tunnel-visioned' points of view!

    I have seen this insular approach so many times in the fire service and I can assure you - it slows progress. Over the past 2-3 decades the smooth .v. fog debate has raged amongst tunnel-visioned enthusiasts! Those that take either stance in the argument are failing to acknowledge the innovative 3D methods of using water-fog. Be assured that Andy's views are acknowledged by me but he only ever presented two-thirds of an argument. When I discussed 3D tactics and methods of using 'pulsing' fog applications with him he was unable to offer a reasoned argument as he had never truly studied this approach. Look at his extensive contibutions in Fire Engineering and you will find no reference to 3D-fog methods but plenty referring to 'indirect (Iowa) methods.

    I think, those of us that have closely researched ALL of the various methods of interior fire attack, do not suffer from such insularity. We are more open-minded. I accept caution and would in fact encourage it. Taking the three methods I have referred to so far -

    1. Direct (smooth-bore/straight-stream) attack
    2. Indirect (Layman/Iowa) water-fog attack
    3. 3D (nozzle pulsing/bursting) water-fog attack

    I have come to learn over 30 years of fighting fires that EACH approach offers the OPTIMUM result under a specific range of conditions and scenarios. To disregard those benefits is being tunnel-visioned.

    What about CAFS for interior attack? Are you able to stand up and say for sure that CAFS is not suited to interior attack? Its another tool - it urges close study - it urges caution - but it MAY well have uses in specific circumstances.

    The confusion you talk of is caused by tunnel-vision. By those who take a stance supporting ONE sided arguments. My approach clearly comes from all three sides (above) and is open-minded about future innovations and how they might impact upon current tactics. Those that base their arguments from one side of the various tactical approaches are equally confused. You can have views - you can have preferences - but to put all your eggs in one basket is causing confusion for others.

    What works for you works. The fires go out! Could you approach certain situations more safely by using the whole range of attack methods? Yes!

    Leave a comment:

  • bpevans
    MembersZone Subscriber

  • bpevans
    replied
    UsingAllHands,
    Nobody wants this thread to turn into yet another smoothbore v. fog nozzle debate. We can agree to disagree on what and how many tools go in the firefighting toolkit. However, just because you disagree with the 3D techniques, does not mean that they come from lack of experience or confusion in fighting fires, which seems to be your implication. They have been proven and perfected for years.

    Leave a comment:

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