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  • #16
    Originally posted by SBrooks
    Yes. Get this: if it's short, we'll lengthen it with 4 more sections of 1 1/2". EP is 220 on the 400', 280 if extended all the way. 125 gpm constant volume fog nozzles. Works for us. Go ask some of the ex-DCFD guys in your borough, there's got to be at least a half-dozen. We generally have 3-4 lines going in within 4-8 minutes of dispatch, and they go in fast, not like gentlemen.

    As one of our retired deputy chiefs described the required flow equation: a little water, and a lot of BALLS. He wasn't so good at math.

    FWIW, we tried the 1 3/4" with 15/16" tip thing for about a year, 6 years ago. Didn't take.
    Yeah, I just had a beer with 2 of those DCFD guys last night. We always get into the Engine debates and most of it centers on Engine operations and the differences in operations (Gentlemen vs. GFY Engine Work)

    It isn't what I would do, but if it works for you guys, good for you! The building construction is different, the tactics are different and if you need to get a line in before the next guy (or the previous guy) then this probably works well.

    Stay safe & wear your chin-strap
    Good Luck, Stay Low & Stay Safe

    Nate DeMarse
    Co-Owner, Brotherhood Instructors, LLC.
    http://brotherhoodinstructors.com
    Facebook Users: Join us here
    -------------------------------
    GET IN THE JOB, BE A STUDENT OF THE JOB!

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    • #17
      I'd take an FDNY truck and a DCFD engine anyday. (not that our trucks are bad)
      Me, I'll stay on the Squad. (Rescue, for for those of you for whom the world stops at the George Washington Bridge)

      Say hi to the guys.

      Comment


      • #18
        Your crosslay lengths should depend on how close you can get to the houses and how big the houses are. Intsead of making your cross lays longer during the winter months, why not use a 300-400' 3" line with a water thief (1-2 1/2"outlet & 2-1 1/2" outlets). Then make some short sections of 1 3/4" (5-6' long "pigtails") hose to get the couplings out of the hose bed, it makes it easier to uncouple the hose, then attach the preconnects to the water thief. This is the setup we use for some of our apartment complexes, it may be take a little longer, but with practice it goes smoothly.

        Comment


        • #19
          Crosslay or Pre-Connect Hose Beds

          In Canada most FD's have the following configurations (Yes we get Summer too sometimes..)

          Trashline 100'-200' of 1-1/2" or 1-3/4"
          Crosslays 100'-200' of 1-1/2" or 1-3/4"
          200' of 2-1/2" for a Blitz Line
          Rear 200-300' of 1-1/2" or 1-3/4" with one each side or two each side
          Rear 400-600' of 1-1/2" or 1-3/4" for longer lays that can be broken
          and then attached to a rear of body face (below hosebed) port

          We are seeing some FD's going with a Booster Reel in either the Dunnage area above the pump or in the Tailboard Compartment with a lightweight 1" or 1-1/2" hose (Niedner REELTEX) that is lighter and easier to use and can flow more than the traditional rubber hose. Riverside County CA FD has 60 Smeal MF (Multi-Functional) Engines with this configuration and seems to work really well for both grass fires and car accidents etc.

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          • #20
            2x 1 3/4" crosslays with auto-fogs at 200'
            1x 2 1/2" rear auto-fog at 200'
            Never argue with an Idiot. They drag you down to their level, and then beat you with experience!

            IACOJ

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            • #21
              We have 150ft of 1 3/4 inch on each of our crosslays and 200ft of 1 3/4 off our back.

              We don't have many houses that are set back from the curb and we found out that extra 50ft is usually in a spagetti pile somewhere so we normal pull the 150ft.

              If we come to a larger house or attic fire we pull the 200 ft off the back, but our 150ft will make the attic at 95% of the homes in our coverage area.

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              • #22
                2) 1-3/4" 150' crosslays 1 off each side color coded to pump panel. 150' of extra 1-3/4" line next to crosslays for extension if needed.
                Last edited by k1500chevy97; 09-30-2006, 04:57 PM.

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                • #23
                  Originally posted by SBrooks
                  Yes. Get this: if it's short, we'll lengthen it with 4 more sections of 1 1/2". EP is 220 on the 400', 280 if extended all the way. 125 gpm constant volume fog nozzles. Works for us. Go ask some of the ex-DCFD guys in your borough, there's got to be at least a half-dozen. We generally have 3-4 lines going in within 4-8 minutes of dispatch, and they go in fast, not like gentlemen.

                  As one of our retired deputy chiefs described the required flow equation: a little water, and a lot of BALLS. He wasn't so good at math.

                  FWIW, we tried the 1 3/4" with 15/16" tip thing for about a year, 6 years ago. Didn't take.
                  My first question is, what is the NP supposed to be on your nozzle? My second is, are you trying to get 125gpm from the nozzle? For the 400ft line I figure you have 200lbs FL flowing 125gpm's. So you have 20lbs NP? With the added 200ft, 4 sections of 50ft 1 1/2, that would be 600ft. flowing 125gpm and FL at 300lbs. Since according to the cheat sheet I have, for 1 1/2 flowing 125 the FL is 50lbs per 100ft. If your EP is 280 for the 600ft line then you are not overcoming the 300lbs FL to get the desired 125gpm's. Unless you don't want 125gpm's. Seems to me if you go by the addage of, little water, and a lot of balls, your asking for trouble in case things go sour. I am not even going to start asking about the manning and 3-4 lines within 4 to 8 minutes. Still trying to figure out the first part. If it works then fine, but I am just trying to figure out how.
                  Vintage Firefighter: The older I get, the braver I was.

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                  • #24
                    30 psi per 100'. Probably not exactlly 125, but more than 100'. I doubt they've been flow tested.

                    33 4 man engine companies, 16 5 man truck companies, 3 5 man rescue companies in 64 square miles.

                    Box alarm = 5 Engines, 2 Trucks, 1 Battalion Fire Chief, 1 Rescue Squad
                    1st Engine lays in to the front, pulls a line through the front door.
                    2nd Engine lays in to the rear, pulls a line to the basement/rear entrance, checks basement, and goes up.
                    3rd Engine pumps first line, backs up first line
                    4th Engine pumps second supply, backs up second line.
                    5th Engine secures 3rd W.S. and stands by as the 'safety company' part of the RIG
                    1st Truck positions at front, ladders & ventilates, assists on fire floor.
                    2nd Truck positions at rear, ladders & ventilates, assists above fire floor.
                    Rescue (two teams) searches fire floor and floor above.

                    This is the basic SOG, there are specific ones for row houses, etc.

                    Comment


                    • #25
                      Ok, so your after just 100gpm's then. That makes sense to me now, amazing how a few gpm's makes that much differnece. I still would rather pull a 3 inch with a gated wye and add the attack lines to it. That's what we do in my carreer department and combination deparment I am a volunteer with. But to each his own. From where I am from we consider it a blessing to have 4 on the pumper any day. You danged big city slickers always seem to have enough to stand around and whizz on the fire to put it out. And thanks for the added info that was cool to see what you have on a response.

                      Speaking of that where I am a carreer firefighter, we have two engines, manned by 3 or 4, one rescue with at least 1, depending on kelly days and such and a minimum staffing of 9 including the Asst. Chief. With the Combination Dept. I am with we have a 3 man crew on first truck on weekdays during the day, these are the paid guys, evening and weekends can have a 4 man crew on the first due engine in the city. Up to six for the second due and up to 5 on the thrid due. For rural, the first truck, 6 man cab, we go with a minimum of the three during work hours and up to 6 other times. Up to 5 on the second truck, a tanker/pumper, and up to 3 on the second and third tankers. We do average about 11 guys on a call even if they end up standing by at the station when not needed on the scene.
                      Vintage Firefighter: The older I get, the braver I was.

                      Comment


                      • #26
                        Originally posted by LtTim556
                        My first question is, what is the NP supposed to be on your nozzle? My second is, are you trying to get 125gpm from the nozzle? For the 400ft line I figure you have 200lbs FL flowing 125gpm's. So you have 20lbs NP? With the added 200ft, 4 sections of 50ft 1 1/2, that would be 600ft. flowing 125gpm and FL at 300lbs.
                        That's not what my chart shows...my trust Waterous pocket chart shows 35 psi/100' loss for 1 1/2" hose at 125 gpm. So, a 400' load would have 140 psi FL in the line, and if they're running 75 psi fixed gallonage nozzles (we have a couple of these on our hi-rise packs and trash lines), they'd need a baseline discharge pressure of 215 psi. That would work. Another 200' extension would add 70 psi in FL in the line, and bring the required discharge pressure to 285 psi (rounded off). So, SBrooks' scenario is well within the realm of the feasible, and if DCFD wants to run really long loads like this, I have to believe they'd have thought of using low pressure fog nozzles, as I've suggested here.

                        Comment


                        • #27
                          Originally posted by bobsnyder
                          That's not what my chart shows...my trust Waterous pocket chart shows 35 psi/100' loss for 1 1/2" hose at 125 gpm. So, a 400' load would have 140 psi FL in the line, and if they're running 75 psi fixed gallonage nozzles (we have a couple of these on our hi-rise packs and trash lines), they'd need a baseline discharge pressure of 215 psi. That would work. Another 200' extension would add 70 psi in FL in the line, and bring the required discharge pressure to 285 psi (rounded off). So, SBrooks' scenario is well within the realm of the feasible, and if DCFD wants to run really long loads like this, I have to believe they'd have thought of using low pressure fog nozzles, as I've suggested here.
                          Checked in another pocket guide I have and it says 38psi FL per 100ft at 125gpm's. Much closer to the 35 you state from Waterous. Now I wonder why the big difference in the two guides. I know it may not be an exact science but damn that much difference. I am not familiar with the the nozzle he was talking about so was not sure about the pressure needed at the nozzle. Anyway both ways cleared a lot up for me. I think I need a new pocket guide now. I wasn't disagreeing or anything just trying to figure that out with what I had. One of the great things about these forums is you can pick the brain of other firefighters and get the answer to your questions. I have been in this business for 26 years and am still learning and relearning. Thanks brothers for the help.
                          Vintage Firefighter: The older I get, the braver I was.

                          Comment


                          • #28
                            Physics, like Math and all the other subjects you learned in the real world, is apparently different in the District of Columbia. Our Pump Manual states 30 psi / 100' of 1 1/2" hose at 125 gpm. It therefore must be true.

                            Nozzles are Akron Assault 125 gpm / 100 psi break apart nozzles.

                            350' 1 1/2" = 205 psi EP
                            400' 1 1/2" = 220 psi EP
                            500' 1 1/2" = 250 psi EP
                            600' 1 1/2" = 280 psi EP
                            plus a handful for elevation

                            pumps are 1250 gpm 2 stage Waterous.

                            When we tried 1 3/4" back in 2000, we used 150 gpm / 75 psi break aparts with a 15/16" slug. I believe we still have the 15/16" cutoffs, but back to the 125/100 nozzles.

                            I don't know what the flow / pressure is actually, but I do know that you get a workable stream out of the butt, it's not particularly powerful, but it will reach across a room.

                            IF (<--notice its a big if) 30 psi / 100' @ 125 gpm is accurate, we get roughly 170 gpm/45 psi on our 200's, and 155 gpm / 35 psi on our 400's when we take the fog tip off.

                            Comment


                            • #29
                              Originally posted by SBrooks
                              Physics, like Math and all the other subjects you learned in the real world, is apparently different in the District of Columbia. Our Pump Manual states 30 psi / 100' of 1 1/2" hose at 125 gpm. It therefore must be true.
                              Originally posted by LtTim556
                              Checked in another pocket guide I have and it says 38psi FL per 100ft at 125gpm's. Much closer to the 35 you state from Waterous. Now I wonder why the big difference in the two guides. I know it may not be an exact science but damn that much difference.
                              Almost any two you pick up will be different...friction loss in hose will be affected by a variety of factors, including the exact composition and construction of the inner lining, temperature, coupling size and type, etc. So, any given pair of charts can be different for a variety of reasons. I've got Waterous pocket charts and a Hale slide rule, both of which I use from time to time, and they don't exactly match. What I like about using pump manufacturers' charts is that they usualy try to midline the loss estimates so that they are close for a variety of types of hose.

                              You also have to be careful in using the charts that come with new hose. First off, they are specific to that manufacturer's hose, which may not have exactly the same characteristics as another manufacturer's hose. Also, they often refer to the loss in the hose itself only, irrespective of things like couplings. It can make a difference...for example, the friction loss coefficient for 2" hose is about 6.5, and that's fine if you have it coupled 2" (as we do). Couple that same 2" hose with 1 1/2" (as most companies do), and it takes your friction loss coefficient up to about 8.0. Not huge, but it will make a difference on a quick reference chart.

                              Similarly, you generally get slightly lower friction loss coefficients from thermoplastic lined hose than rubber-lined hose, and rubber-lined hose made in recent years often has lower coefficients than older rubber-lined hose.

                              Anyway, most of these charts will be close to each other, but all of the calculations used to make them are theoretical. You won't really know what your particular setup gives you unless you flow test it yourself (which is something else I bet DCFD has done at some point).
                              Last edited by bobsnyder; 10-19-2006, 11:22 AM.

                              Comment


                              • #30
                                Originally posted by ecfr1978
                                Your crosslay lengths should depend on how close you can get to the houses and how big the houses are. Intsead of making your cross lays longer during the winter months, why not use a 300-400' 3" line with a water thief (1-2 1/2"outlet & 2-1 1/2" outlets). Then make some short sections of 1 3/4" (5-6' long "pigtails") hose to get the couplings out of the hose bed, it makes it easier to uncouple the hose, then attach the preconnects to the water thief. This is the setup we use for some of our apartment complexes, it may be take a little longer, but with practice it goes smoothly.
                                I dont really like the water thief or gated wye idea, only because now if you get a burst length of 3", or whatever size the hose is, before the wye, you just put the line on the fire floor and the line on the floor above OOS. Id rather see different lines coming off the rig. But if it works for you, stick with what you know....
                                Proud East Coast Traditionalist.

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