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  • Aspirating sprinkler heads

    Anyone out there have experience with aspirating sprinkler heads for foam production in an industrial setting? Fixed installation of sprinklers to produce AR-AFFF finished foam for protection of methylhydorsilane storage. Info such as head pressure and flow to optimize the foam production using 3% AR-AFFF through an eductor feeding the fixed installation.

  • #2
    What size are the containers

    Are they inside or out

    What kind of facility are they at
    http://www.youtube.com/watch?v=JZdEH...e_gdata_player

    Comment


    • #3
      Suggest you get the msds from the place using/ storing it to see what it actualy says

      This one does not look to bad except for the possible acid release

      http://www.cnf.cornell.edu/msds/meth...est(50529).pdf
      http://www.youtube.com/watch?v=JZdEH...e_gdata_player

      Comment


      • #4
        fire49: The MSDS is available and in our response sog's. I am looking for practical experience with supplying the installation having to pump to a fixed system through an eductor. I understand how to supply a hand line with a proper foam solution, but am concerned that without the correct flow rates on the heads, the amount of aspirated air entraned by the sprinkler heads will not be enough to provide the needed amount of finished foam. This expansion ratio also greatly affects the amount of foam concentrate that needs to be carried on the engine supplying the sprinkler. In addition to the expansion ratio, there is the problem of achieving the correct flow rate and drop across the eductor. Back pressure on a hose line can be calculated using friction loss formulas and nozzle design pressures, but I am unsure of the pressure curve of the aspirating sprinkler heads. The Ansul information on the net is very minimal, and does not provide any flow rate - pressure - aspiration data. I am also unsure as to what manufacturer provided the present heads. Just looking for anyone with experience with this type of fixed installation.

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        • #5
          So let try to understand the set up

          Are the sprinkler heads open or closed ?

          You bring the pump?

          You bring the educator?

          You bring the foam?

          Once again is this inside a building or outside?

          What size are the containers ?

          Do you know how old the system is?? Roughly
          http://www.youtube.com/watch?v=JZdEH...e_gdata_player

          Comment


          • #6
            Originally posted by KuhShise View Post
            I understand how to supply a hand line with a proper foam solution, but am concerned that without the correct flow rates on the heads, the amount of aspirated air entraned by the sprinkler heads will not be enough to provide the needed amount of finished foam. This expansion ratio also greatly affects the amount of foam concentrate that needs to be carried on the engine supplying the sprinkler. In addition to the expansion ratio, there is the problem of achieving the correct flow rate and drop across the eductor. Back pressure on a hose line can be calculated using friction loss formulas and nozzle design pressures, but I am unsure of the pressure curve of the aspirating sprinkler heads. The Ansul information on the net is very minimal, and does not provide any flow rate - pressure - aspiration data. I am also unsure as to what manufacturer provided the present heads. Just looking for anyone with experience with this type of fixed installation.
            This will almost certainly be an engineered system with designs and flow requirements on file. Have you talked to the building owner? There should be at least some design information in the sprinkler room -- at least enough to identify the design standard used and the designer.

            A facility with that level of specialized fire control systems also probably requires a fire management plan of some sort. Do they have one? What does it say about the system? Have you contacted your local Fire Marshal's office (or whoever inpects the system in your jurisdiction)?
            Last edited by DeputyMarshal; 05-15-2011, 02:31 PM.
            "Nemo Plus Voluptatis Quam Nos Habant"
            sigpic
            The Code is more what you'd call "guidelines" than actual rules.

            Comment


            • #7
              System, as far as I can tell was installed without a whole lot of communication between the FD and the industry. It is a dry system with open heads (4) arranged to protect a storage area of about 30 by 40 inside an ordinary construction. Concrete block with steel bar joist and rubber covered steel deck roof. FD is expected to supply the siamese with foam solution, but there is no volume or pressure specified. In discussing this with the chief at the time of construction, the FD was simply told to feed the system with the foam solution. No pressures or volumes specified. We carry 95 gpm in line eductors with 1 1/2" NH threads. We have one engine with an around the pump proportioner, but it is only for class A foam at 0.1% wildland use. The process is a closed system with vapor recovery, so it is well contained from the process standpoint. The operation is being considered for expansion, but the storage area will remain the same. I understand the hazard involved with a vapor escape, and the first due is equipped with adequate B/A to ensure crew & P.O. have B/A available. I have not been privy to the operation, so hesitate to answer on size of the containers. From some discussions, the containers are moved by fork lift, so I assume 3 to 4,000 lbs. Original system has been in place for about 10 years

              Comment


              • #8
                Originally posted by KuhShise View Post
                Original system has been in place for about 10 years
                That's not all that old a system. Somebody at the plant should at least know who designed it and what standard it was designed to.

                Are there fire codes in force in your jurisdiction? If so, what are they and who enforces them?

                If the owners can't provide design specifications, the realistic alternative is to require them to provide a system analysis by a licensed engineer familiar with this type of system. It isn't up to you as the fire department to guess how to support a non-standard system with no design specifications available to you.
                "Nemo Plus Voluptatis Quam Nos Habant"
                sigpic
                The Code is more what you'd call "guidelines" than actual rules.

                Comment


                • #9
                  Hate to say it but sounds like some one installed some pipe and stuck heads on them, with no design criteria


                  The sprinkler head should have markings on it at least who made it

                  So no pre plan / walk thru of the building.?? Done lately

                  I think I would want to know a lot more about what is inside
                  How stored container size what other nasty things processes going on


                  Is the rest of the building sprinkled ??? More then likey not
                  Last edited by fire49; 05-16-2011, 02:52 PM.
                  http://www.youtube.com/watch?v=JZdEH...e_gdata_player

                  Comment


                  • #10
                    Any chance of putting it (the system) on a flow meter and doing a live flow test? Not with foam but just to establish flow rates. I'm guessing ideal conditions would require 100 psi at the head, not sure how you would do that unless you screw a inline guage behind the head. Luck with that, interested to find out what you do. If you need a flow meter, give me a call. I can shoot one up to you.

                    Comment


                    • #11
                      Originally posted by Truck_3 View Post
                      I'm guessing ideal conditions would require 100 psi at the head.
                      "Guessing" is no way to run an engineered fixed supression system.
                      "Nemo Plus Voluptatis Quam Nos Habant"
                      sigpic
                      The Code is more what you'd call "guidelines" than actual rules.

                      Comment


                      • #12
                        Originally posted by KuhShise View Post
                        System, as far as I can tell was installed without a whole lot of communication between the FD and the industry. Have you checked with the local Code Enforcement Office and/or the Fire Marshal's office? All commercial building plans are required to be kept on file (forever) by Pa. State Law. Perhaps the Code Official and/or the FM have some knowledge of the system. It is a dry system with open heads (4) arranged to protect a storage area of about 30 by 40 inside an ordinary construction. Concrete block with steel bar joist and rubber covered steel deck roof. FD is expected to supply the siamese with foam solution, but there is no volume or pressure specified. In discussing this with the chief at the time of construction, the FD was simply told to feed the system with the foam solution. No pressures or volumes specified. We carry 95 gpm in line eductors with 1 1/2" NH threads. We have one engine with an around the pump proportioner, but it is only for class A foam at 0.1% wildland use. The process is a closed system with vapor recovery, so it is well contained from the process standpoint. The operation is being considered for expansion, but the storage area will remain the same. I understand the hazard involved with a vapor escape, and the first due is equipped with adequate B/A to ensure crew & P.O. have B/A available. I have not been privy to the operation, so hesitate to answer on size of the containers. From some discussions, the containers are moved by fork lift, so I assume 3 to 4,000 lbs. Sounds like "totes" of foam. Original system has been in place for about 10 years
                        I would immediately find any and all documents on the existing system through the FM's Office and the Code Official. Was it designed, installed and inspected properly? Was there an acceptance test? If you can find nothing, then I would politely ask the Business Owner to hire a Fire Protection Engineer (registered in the Commonwealth of Pa.) to conduct a full evaluation of the system for both design compliance and system function testing. If the property owner refuses, then have the Fire Marshal's Office tell them to have it done, especially if there are no valid permits for the system. If the system is not up to par, it is up to the property owner to bring it up to date. Have the FPE design corrections into the system, or a new one alltogether, and have the system altered or rebuilt under a building permit so that it is done correctly and under the supervision of Code Enforcement and/or the FM's Office.
                        Last edited by FWDbuff; 05-16-2011, 05:10 PM.
                        "Loyalty Above all Else. Except Honor."

                        Comment


                        • #13
                          Originally posted by DeputyMarshal View Post
                          "Guessing" is no way to run an engineered fixed supression system.


                          Looking at what K has already written, Does this sound like an engineered system to You?

                          Comment


                          • #14
                            Originally posted by Truck_3 View Post
                            Looking at what K has already written, Does this sound like an engineered system to You?
                            Quite possibly a badly engineered system but an engineered system nonetheless.

                            The long and short of it is that figuring out how to operate it isn't the FD's job. (Nor is the typical FD competant to figure it out even if it was thier job...) It's up to the building owner to come up with credible design specs on the system that should include parameters for supplying the system.
                            "Nemo Plus Voluptatis Quam Nos Habant"
                            sigpic
                            The Code is more what you'd call "guidelines" than actual rules.

                            Comment


                            • #15
                              Originally posted by FWDbuff View Post
                              If you can find nothing, then I would politely ask the Business Owner to hire a Fire Protection Engineer (registered in the Commonwealth of Pa.) to conduct a full evaluation of the system for both design compliance and system function testing.
                              Bingo!
                              "Nemo Plus Voluptatis Quam Nos Habant"
                              sigpic
                              The Code is more what you'd call "guidelines" than actual rules.

                              Comment

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