1. #1

    Join Date
    Jul 2007
    Posts
    3

    Question FDC's for sprinkler systems

    Recently at my firehouse, we have been talking about and doing a simulated fire at a building with an FDC for the sprinkler systems. When my shift was doing our simulation, the building we were dealing with was a grocery store with a fire in the loading dock area. On arrival, the "conditions" were smoke and fire showing from this loading dock, and the sprinkler system was active. My chief decided that instead of our 4 man engine company hitting the FDC, we would let the sprinkler system work w/out our assistance, and we simulated an aggressive offensive attack on the loading dock. the evaluators of the scenario acted as if my chief committed a crime by not hooking into the FDC. In a post scenario critque, our shift discussed the tatics used and supported them by stating: that if the sprinkler is keeping the fire at bay, an aggressive fire attack with the sprinkler system operating is sometimes an acceptable strategy. My questions are: Why is it preached as it is ALWAYS a MUST to hook to the FDC? If you hook into the FDC for the sprinkler system and use a hydrant that is on the same feed as the sprinkler system, are you really able toboost the pressure and get more water flowing into the system? If any one can answer these questions I would appreciate it. My chief has looked in all the books around the station and can not find an explanation on the absolute reason why it is imperative to hook the FDC vs. using it in conjunction with an aggressive attack.

  2. #2
    MembersZone Subscriber

    Join Date
    Sep 2006
    Location
    Northeast Coast
    Posts
    3,887

    Default

    THis is pretty interesting as I just got out of a class on sprinkler systems being put on by an NFPA rep that sits on the NFPA 13 board. He clearly explained that the FDC was never intended to be able to supply the system at full capacity! News to me, I had not heard this before. Basically he said that if the system works as designed the sprinklers will work better using the normal water connection vs. our pumped FDC. So he says the system is designed for a required flow and unless you suspect some sort of damage pumping it should have little to no real effect. The quarterly or biannual test are there to ensure the system always works as designed so in my eyes it may be time we rethink always hitting the FDC first. I'm sure there are plenty of FD's that have always known this and don't put as much emphasis on the FDC connection in initial stages.

    The one thing I'd like to see is some sort of external gauge showing residual pressure of the sprinkler riser entrance water. This would let you know how close you are to running out of system water then requiring pumping the FDC.

  3. #3
    Forum Member
    Higby916's Avatar
    Join Date
    Jun 2007
    Posts
    184

    Default

    I too was always under the impression that hooking into the FDC would boost pressure and help with fire attack. To be honest, I've never seen it done (only because I've never seen a large fire where there were sprinklers) so I truly do not know. It would seem that this would be good knowledge to have, save time by not hooking into the FDC and attack aggressively right away. I suppose you could hook into the FDC once the hydrant is caught and the pump is supplied, but if it does nothing, why bother?

    I'm confused now. Why even have the hookups if they were never intended to boost pressure?

  4. #4
    MembersZone Subscriber

    Join Date
    Sep 2006
    Location
    Northeast Coast
    Posts
    3,887

    Default

    Quote Originally Posted by Higby916 View Post
    I too was always under the impression that hooking into the FDC would boost pressure and help with fire attack. To be honest, I've never seen it done (only because I've never seen a large fire where there were sprinklers) so I truly do not know. It would seem that this would be good knowledge to have, save time by not hooking into the FDC and attack aggressively right away. I suppose you could hook into the FDC once the hydrant is caught and the pump is supplied, but if it does nothing, why bother?

    I'm confused now. Why even have the hookups if they were never intended to boost pressure?
    I believe it is possible to "boost" the pressure, but the flow can only increase marginally due to the orifice size. I also should note, that the system will do what it is designed for, which I believe is to deliver flow to a specific number of heads vs. all of the heads. But in fact NFPA does not require the FDC to be able to flow even the design flow of the system so as it sounds we really are connecting it incase there is a water supply issue. Of course we could create this issue by tapping into the water mains. I know I'm going to research this further.

  5. #5
    Forum Member
    Dave1983's Avatar
    Join Date
    Oct 2003
    Location
    Gator Country
    Posts
    4,157

    Default Well...

    Sprinkler systems are designed under the assumption that only 'x" number of heads are going to activate at any one time. If a fire is large enough to activate more heads, you may start to have less flow/pressure then required for the system to operate properly.

    Demand increases and fluctuations in your areas water system will also effect available pressure for a sprinkler system that doesnt have a fire pump on site.

    For those reasons alone, its always a good idea to supply an FDC. You dont have to pump it, but at least hook up.
    Fire Marshal/Safety Officer

    IAAI-NFPA-IAFC/VCOS-Retired IAFF

    "No his mind is not for rent, to any god or government"
    RUSH-Tom Sawyer

    Success is when skill meets opportunity
    Failure is when fantasy meets reality

  6. #6
    MembersZone Subscriber

    Join Date
    May 1999
    Location
    Here, There, Everywhere
    Posts
    4,191

    Default

    What kind of fire officers are these judging this simulation? How much fire have they seen? Are they hoping to avoid fire duty at all costs?

    I can't understand how they would be upset at conducting an offensive attack.

    1. I imagine your staffing isn't such that you could stretch and operate a line and initally along with supplying the sprinler siamese. Could the Engine Chauffeur after securing a positive water supply and supplying your handline not drag a supply line to the siamese?

    2. If you show up and there is an obvious fire condition in a building with sprinklers, the success of augmenting is a crap shoot at best. The fire condition means the sprinlers proably didn't finish the job and that we are going to have to finish it off...perhaps they are blocked by stock. Perhaps there are illegal alterations...etc. who knows...what that officer does know that using skilled firemen with a handline that fire will most certainly go out.

    3. sprinklers are there to support our fire extinguishment efforts they are not meant to take the place of us(despite what polticians think)...if they don't work properly or just can't do the job we still have to do what we are paid to do and that is stretch in and put out the fire.

    ______________________________________

    Around here in Standpipe buildings the Standpipe siamese ALWAYS gets supplied first and then the sprinler siamese if it serves the floor on fire.

    For all other buildings the order of supplying the siamese on lets say a taxpayer with spinklers in the cellar would be:

    1st due if possible
    2nd due if possible
    3rd Due Must if the previous two were unable to get to it.

    The reason you couldn't find any justification in any text book is there is no documented support for such a position in recognized texts. It was simply their opinion and an ignorant one at that. I'll see what I can find in terms of supplying sprinklers in some texts.

    FTM-PTB

  7. #7
    MembersZone Subscriber

    Join Date
    Sep 2006
    Location
    Northeast Coast
    Posts
    3,887

    Default

    A little research on my part brought up a decent point if you're in a district like ours that has a poor water system. If the design flow, like Dave noted (x number of heads) is flowing and you connect your engines to the system and begin using water you could reduce the flow to the sprinkler heads allowing the fire to overcome the sprinklers. But under normal circumstances, you'd have a decent fire that already fused the number of heads in the design flow and would have to be flowing water yourself. In which case a crew flowing water should be in the fire area.

  8. #8
    Forum Member

    Join Date
    Dec 2007
    Posts
    129

    Default

    OK some infromation to help when fighting a fire in a sprinklered building:

    1.The sprinklers knows where the fire is, you have to find it, so why not let the sprinklers do what they are designed to do. Keep the fire in check until you find the fire, except if you have ESFR sprinklers which are designed to extinguish the fire, more on that below.

    2.Sprinkler system design requires the designer to include water for FD hose lines. How much water is based on the occupancy. For an Office 100 gpm, Mercantile 250 gpm, Manufacturing 250 gpm, Flammable Combustible Liquid Operations 500 gpm, Warehouses 500 gpm. So if you flow more water i.e. more hand lines then the designer included in the sprinkler design then you are taking water from the sprinklers that know where the fire is and you do not.

    3.Check out NFPA 13E FD Operations in a Sprinklered Building for how it all works and what u as the FD should do.

    4.NFPA 13 requires the designer to hang a placard on the sprinkler riser as to the design of the systems and how much water and pressure the system requires. Look for them when you do an inspection of the site. Depending on the occupancy some sprinkler systems may exceed the pumping capacity of your engine. Warehouses, flammable liquid operations, aircraft hangers, may have high GPM flows. You can see flows of 1,500 to 3,000 gpm and sometimes with aircraft hangers 15,000 gpm. Some FD have posted the GPM at the FDC so they know what size engine to place on the FDC.

    5.The higher the pressure you pump into the FDC the more water will come out of the sprinklers. NFPA 13E requires 150 psi to the FDC. If you have a city pressure of 60 psi and you boost the pressure to 150 psi you will significantly increase the amount of water coming out of the sprinkler. The more water out of the sprinkler the more wet stuff on the red stuff, the quicker the red stuff will go out. The formula to determine gpm flowing is as follows: The square root of the pressure times the K factor equals gpm. So if a sprinkler has a K factor of 5.6 and has 60 psi at the head is will flow 43 gpm (square root of 60 psi is 7.74 times 5.6 = 43.37 gpm) If the pressure doubles to 120 psi the same head will now flow 61 gpm.

    6.ESFR sprinklers installed in many new warehouses and are designed to extinguish the fire. They can extinguish a plastic fire on racks 40’ high in a 45’ building before you arrive on the scene if installed properly and maintained. The 1st sprinkler activates within one minute of the fire and extinguishment occurs with 3-5 minutes. ESFR sprinkler design is only 12 sprinklers operating at one time. GPM for ESFR sprinklers are about 1000-1600 gpm for the sprinklers and 250 gpm for hose lines.


    7.You can have 1,000 sprinklers in the building, BUT the design is only for say 20 sprinklers operating at one time. The sprinkler system design is based on the occupancy but never more then 30-40 sprinklers and most likely 10-20 or less sprinklers operating at one time. The underground water main, riser and piping are all designed on only 20 or so sprinklers operating. If you have a fire where more then say 20 or more activated it is a reason to investigate the fire. The reason may be because the valve to the sprinkler system was closed or the occupancy changed but the sprinkler design did not, hence not enough water to control the fire. Example if the building was designed for metal can storage and that company moves out and the new company is now storing plastic cans, a plastic can will produce more heat hence more water is required from the sprinkler system.

    Hope this helps if you have any questions please ask.
    Last edited by InsuranceLCRep; 02-17-2008 at 08:17 AM.

  9. #9
    Forum Member

    Join Date
    Dec 2007
    Posts
    129

    Default

    "The one thing I'd like to see is some sort of external gauge showing residual pressure of the sprinkler riser entrance water. This would let you know how close you are to running out of system water then requiring pumping the FDC."

    With few exceptions the water main connected to the fire hydrant is the same water main for the fire sprinklers. The pressure coming into your engine will be about the same pressure at the sprinkler riser. So if you have 30 psi on your incoming gauge then you have 30 psi or less the sprinkler riser. You can get technical and calculate the friction loss of the supply hose to your engine, difference in elevation, distance from your engine to the fire, etc. BUT rule of thumb is to use the incoming pressure to your engine.

    The more water your hose lines use to control the fire the more water you are taking away from the sprinkler system. Thus the reason for the FDC to provide an adequate water supply to the sprinklers. Think of it this way it is another hose line you have to maintain pressure and flow to during a fire. YES no brothers are on the end of the line, BUT that line is helping by controlling the fire. Faster knock down, less smoke, less fire and less chance of a brother being injured.:)
    Fire Sprinklers Save Firefighters’ Lives Too!

  10. #10
    MembersZone Subscriber
    mcaldwell's Avatar
    Join Date
    Apr 2003
    Location
    Panorama, British Columbia, Canada
    Posts
    3,022

    Default

    Thanks for the input Tom, some good points there.

    I know for a certainty that in my district with some limited flow areas (on one giant dead-end system), as soon as we connect to the hydrant and start moving water, we are going to starve the sprinkler really fast. If we have direct access to ALL the fire, we may be able to win, but how many times do we know the full extent of fire development before we begin filling and flowing lines? And how many times do we leave resources available to do this task after we begin interior ops?

    I would think that this is less of a concern in a large urban environment with a good system (especially with a fire pump), so I would not say unequivocally that there should be a hard and fast rule that you ALWAYS connect the standpipe first, but second due should grab it.

    The comment that sprinklers that have failed to extinguish the fire upon arrival are useless doesn't always hold water either. Remember that 1 Meridian Plaza was extinguished after almost 20 hours by a handful of heads on the 30th floor. There were no heads in the lower floors, so it had no effect upon intial attack, but it proved the value of a system even after the fire had long escaped the control of the Philly FD.

    Firefighters (especially career) don't like to think that sprinkers are more valuable than FF's, but the fact is undisputed that where they are installed, they put out FAR more fire than we do.
    Never argue with an Idiot. They drag you down to their level, and then beat you with experience!

    IACOJ

  11. #11
    Forum Member

    Join Date
    Dec 2007
    Posts
    129

    Default

    I think of automatic sprinklers as Jake ready to go. As with any Jake stuff can happen. Stuff like closed valves, arsonist #1 way to defeat the system. BUT if it is a single riser wet system the FDC comes in above the shut off valve most times, unless the FDC is at the pit at the street. So even if the valve is closed, if the FD connects to the FDC they can start feeding water onto the fire. How long does it take to connect to the FDC vs. stretching a line and finding the seat of the fire? I would think the FDC would win that race.

    Another way an arsonist or even some stupid kid can take the sprinkler protection out of service is by placing a tennis ball/Coke can into the FDC. At 150 psi the ball/can is pushed/carrier to where the sprinklers are flowing. The ball/can has no problem passing through 4” FDC pipe or the riser, but when it gets to smaller branch lines it will get stuck and stop or significantly reduce the flow of water to the sprinklers. Lesson for the fire inspector and 1st due engine is to check the FDC to make sure caps are on and nothing is obstructing the openings.

    Fire pumps and FDC are another area of concern. Some think they do not need to connect to the FDC if the pump is running, BUT they do! Fire pumps can be and are often set up to shut down after 7 minutes of operation. Not a big deal with an electric pump, system pressure is low so the fire pump starts back up for another 7 minutes. BUT what about a diesel driven fire pump? It starts the same way your diesel engine on your pumper does, by 12 volt batteries. What happens if the battery was just strong enough to start the pump and after 7 minuets it stops, and does not start because of a weak battery? Perhaps you are just getting a line into operation or worst yet inside working and all of a sudden you loose your overhead protection and conditions go from bad to worst very fast. If the engine is connected to the FDC it will take the place of the fire pump and supply water to the sprinkles.
    Last edited by InsuranceLCRep; 01-05-2008 at 09:20 PM.
    Fire Sprinklers Save Firefighters’ Lives Too!

  12. #12
    Forum Member
    nmfire's Avatar
    Join Date
    Nov 2002
    Location
    Maryland (DC Suburb)
    Posts
    5,738

    Default

    I would just like to point out something here. A fire is not "kept at bay". It is either getting bigger, or getting smaller; not staying in one place like a dog inside a fence.

    Sprinklers will either make the fire smaller, or slow down how fast it gets bigger. In either case, I trust the engine supplying an FDC a lot more than the city water pressure or whatever defunct fire pump the system has running it.
    Even the burger-flippers at McDonald's probably have some McWackers.

  13. #13
    Forum Member

    Join Date
    Dec 2007
    Posts
    129

    Default

    "Sprinklers will either make the fire smaller, or slow down how fast it gets bigger. In either case, I trust the engine supplying an FDC a lot more than the city water pressure or whatever defunct fire pump the system has running it"

    Just make sure the engine is big enough to supply the water to the FDC. Not a problem for mercantile, most manufacturing, offices, occupancies BUT with higher fire loading occupancies the sprinkler system may require more then your engine is capable of supplying. Warehouses with plastics, flammable and combustible liquids, aerosols, etc. could have sprinkler demands of over 2500 gpm and higher. What size pump does your department run with on its engines?
    Last edited by InsuranceLCRep; 01-05-2008 at 09:16 PM.
    Fire Sprinklers Save Firefighters’ Lives Too!

  14. #14
    Forum Member
    nmfire's Avatar
    Join Date
    Nov 2002
    Location
    Maryland (DC Suburb)
    Posts
    5,738

    Default

    Fortunately, we don't have any commercial occupancies that large. All our pumps are 1500gpm. Pre-plans all specify to hook up to the FDC as soon as practical.

    I can see how a huge facility would easily be more than one of our pumps can handle (I work in one). In that case, we have to rely on the fire protection system being a good one.
    Last edited by nmfire; 01-05-2008 at 10:53 PM.
    Even the burger-flippers at McDonald's probably have some McWackers.

  15. #15
    Forum Member

    Join Date
    Dec 2007
    Posts
    129

    Default

    If you do not have the latest NFPA codes and need to research the codes, here is link. You may read BUT not print any NFPA code/standard.

    NFPA 13E is the code for FD operations with sprinkler or standpipe systems.

    http://www.nfpa.org/aboutthecodes/li..._standards.asp

    Click on the code you want

    Then go to the bottom of the page and click on "Preview this document".

    Then click I agree

    Then click on the code you choose at the bottom of the page
    Fire Sprinklers Save Firefighters’ Lives Too!

  16. #16
    Forum Member

    Join Date
    Dec 2007
    Posts
    129

    Default

    What is wrong with this picture? Always walk around a builiding when finished or before you go inside for your inspection.
    Last edited by InsuranceLCRep; 09-05-2008 at 09:35 PM.
    Fire Sprinklers Save Firefighters’ Lives Too!

  17. #17
    Forum Member
    nmfire's Avatar
    Join Date
    Nov 2002
    Location
    Maryland (DC Suburb)
    Posts
    5,738

    Default

    I give up. What the hell is that?
    Even the burger-flippers at McDonald's probably have some McWackers.

  18. #18
    Forum Member
    DeputyChiefGonzo's Avatar
    Join Date
    Aug 2000
    Location
    Somewhere between genius and insanity!
    Posts
    13,584

    Default

    It's a garden hose connection. It is key activated to prevent unauthorized personnel from using rhe spigot.
    ‎"The education of a firefighter and the continued education of a firefighter is what makes "real" firefighters. Continuous skill development is the core of progressive firefighting. We learn by doing and doing it again and again, both on the training ground and the fireground."
    Lt. Ray McCormack, FDNY

  19. #19
    Forum Member

    Join Date
    Dec 2007
    Posts
    129

    Default

    Quote Originally Posted by nmfire View Post
    I give up. What the hell is that?

    During a routine inspection, a Fire Inspector advised the business they needed to label the FDC outside of the building. The maintenance man called the Inspector back a few days later to clarify… The Inspector advised him to “simply label the hose connection outside.” (The real FDC is actually on the other end of the strip mall.) Confused, but without hesitation, the maintenance man did exactly what he was told. I would have loved to hear the conversation during the re-inspection.


    http://www.vententersearch.com/?paged=9
    Last edited by InsuranceLCRep; 01-06-2008 at 05:29 PM.
    Fire Sprinklers Save Firefighters’ Lives Too!

  20. #20
    Forum Member
    nmfire's Avatar
    Join Date
    Nov 2002
    Location
    Maryland (DC Suburb)
    Posts
    5,738

    Default

    Ah. So that must be for the FD to hook into for small shrubbery fires.
    Even the burger-flippers at McDonald's probably have some McWackers.

  21. #21
    MembersZone Subscriber
    npfd801's Avatar
    Join Date
    Aug 2002
    Location
    Somewhere in Illinois
    Posts
    2,221

    Default

    All this talk of K factors, NFPA codes etc. is giving me flashbacks. I once designed fire sprinkler systems for a living and now I'm having cold sweats... Nothing more fun than hydraulic calculations for a sprinkler system.

    I understand that there are some hard and fast rules we have to live by in the fire service, but like everything else - I think there needs to be an educated decision regarding what priority connecting to the FDC is in our order of initial ops at a suspected or actual structure fire.

    Say perhaps in a residential occupancy with a high potential for many lives to be at risk unless a well involved compartment fire is knocked down quickly. If the building is sprinklered, and you see flames blowing out of a window, I would say something is going on with that system. Do you take your chances and boost the FDC or do you make an aggressive attack and go after it? I know what my answer would be.

    By the same token at a business occupancy at 3 am with no cars in the lot, I might commit my crew to pumping that FDC before I send anyone in...

    I'm tired, and it is late, but that's just my food for thought on this one.
    "Share your knowledge - it's a way to achieve immortality." - Stolen from Chase Sargent's Buddy to Boss program

  22. #22
    MembersZone Subscriber
    FFPotenziano's Avatar
    Join Date
    Aug 2005
    Location
    Tampa, FL
    Posts
    46

    Default Pump the FDC or not

    If your pumping the FDC at 150psi for 5 minutes and you realize you need to increase the pressure, would that be an indicator that more heads have opened and fire is growing?

    If you can't compress water, why not pump to the FDC? You'll make up the pressure loss and you'll have a gauge on the FDC (your pump).
    Last edited by FFPotenziano; 03-07-2008 at 09:53 PM. Reason: Error

  23. #23
    Forum Member

    Join Date
    Dec 2007
    Posts
    129

    Default

    [QUOTE=FFPotenziano;929090]If your pumping the FDC at 150psi for 5 minutes and you realize you need to increase the pressure, would that be an indicator that more heads have opened and fire is growing?QUOTE]

    Yes, as more sprinklers open the pressure will drop, indicating the fire is getting larger. Depending on the occupancy and hazard u may see a big drop or a small drop. An office the design is about 10 gpm per head, so if 6 heads activate u will be flowing about 60 gpm. If this is a warehouse the flow maybe 60-100 gpm per sprinkler, same 6 heads, now u are flowing 350-600 gpm, u will see a drop in pressure with this flow.
    Fire Sprinklers Save Firefighters’ Lives Too!

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Diesel Exhaust Systems
    By FireCritic in forum Firefighters Forum
    Replies: 20
    Last Post: 08-04-2005, 11:54 PM
  2. Station Alerting Systems
    By emaziarz in forum Career/Paid Firefighters Forum
    Replies: 3
    Last Post: 09-08-2004, 02:31 PM
  3. FDC's and Sprinkler systems
    By backsteprescue123 in forum Firefighters Forum
    Replies: 0
    Last Post: 04-25-2004, 03:04 PM
  4. "MAYDAY" systems discussed
    By NJFFSA16 in forum University of Extrication
    Replies: 1
    Last Post: 10-07-2002, 03:05 PM
  5. ROBWEN foam injection systems
    By anthony mattingly in forum Firefighters Forum
    Replies: 0
    Last Post: 11-14-2001, 03:32 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts

Log in

Click here to log in or register