Multiple fire risers and multiple FDC's

[moondoggy]

We recently installed two separate risers covering several different areas of the building. Each is covered by its own FDC located on the same side of the building.

The fire marshal recently commented that the two fire systems have to be connected together, With one FDC. Is this an NFPA code requirement or other national code requirement?

 

[TravisMack]

Moondoggy:

The figure in questions shows:
Tapping the city main--> installing piping from the city main to an underground pit-->in the pit you have in direction of flow: check valve->gate valve->FDC-->then the diagram indicates to continue to your system.

Travis

 

[stookeyfpe]

Well Travis, since you asked:

I agree with your interpretation. The last mega warehouse/manufacturing/Group H occupancy I reviewed and approved was a 764,000 square foot bottled water plant (largest in North America). We installed a master Fire Department Connection downstream of the pump suction. The FDC had its own 100 foot feed main and was located near a municipal hydrant. Frankly, these demands are starting to get so big with the new sprinkler technology I am really scrutinizing pipe sizes for remote FDCs.

While our designs are different, your going to be in the same condition if the pump takes a dump. That is why an accessible, easily identified FDC is so important.

I believe NFPA 13 gives us the flexibility to allow both designs. My question is "what is the other option?" In your case Travis, 33 different FDCs sure as hell will confuse the responders and then that is when the poo hits the fan. Firefighters must understand (especially in warehouses protected by the new sprinkler technology) that they need to start pumping the FDCs as their first fireground action, not their third. Second action: send a firefighter to the pump (when one is provided) to make sure it is running.

Sorry about my delay in responding but I am in the nation's capital at hotel that darn sure is not worth $185 for a one day meeting.

 

[moondoggy]

Hi TravisMask,

Thanks for the information. One final question. After it says "continue to your system", does it infer that it goes only to a building sprinkler system or does it suggest both the building sprinkler system and the private hydrants around the facility???

I did come across a Santa Clara County, CA report online that confirms they have such a system for in the report they state to paint the tops of the private hydrants white to indicate that these are also fed from the single FDC.

 

[TravisMack]

There is no further description to indicate what it goes to..

Not to beat you up over anything, and I don't mind paraphrasing information for you, but you can go to NFPA.org and I believe you can purchase a PDF copy of the NFPA 13 fairly cheap. I know it is a lot cheaper than 700' of pipe through a live facility

If I could cut and paste the diagram for you, I would...but I don't know how to do it on this forum.

Travis

 

[TravisMack]

Scott -

I hope you are getting in some sight seeing in DC. My wife is on the hunt for homes to look at in TX. She is ready to go today. She is looking at DFW / Ausin / San Antonio. The home prices seem so "cheap" compared to Phx.

I agree entirely on the FDC not be sized enough. I was shot down by the PM on the large warehouse I mentioned above. We had a system demand in the 2000+ gpm range for one of the areas that was flammable liquid storage. I wanted to calculate the system to the FDC and let the FD know what pressure they needed to be able to provide. I also wanted to run the FDC to match the fire pump discharge size - 10" for this project. However, the sprinkler contractor PM for the project shot that down. He was adamant that they were only going to install a 4" siamese connection. I think that I finally got him to at least accept a 6" x 2.5"x2.5"x2.5" FDC. His rationale was that according to NFPA (and this was supported by communication from NFSA) that the FDC is not meant to be the sole supply of a system, and only a supplement. Therefore, the 4" should be adequate to supplement. The only time the FDC is the supply is for a manual standpipe.

Travis

 

[cdafd]

TravisMack
not sure what you do but san antonio city is looking for a fpe and use to be cheaper to live there than austin, dallas area prices are all over the place depending on where you want to live.
"His rationale was that according to NFPA (and this was supported by communication from NFSA) that the FDC is not meant to be the sole supply of a system, and only a supplement."
Have heard that also. A question would be does the lcoal fire dept have the pumper or pumpers and the knowledge to supply a higher demand system.

 

[TravisMack]

cdafd:

I am just a lowly NICET IV Fire Sprinkler System Eng Tech Or something like that...just get paid to play connect the dots..

 

[stookeyfpe]

Travis:

If you were in my jurisdiction you would have sized the FDC for the demand. Especially for a high challenge risk like flammable liquids.

And IMHO, some of those NFSA interpretations are crap and are only intended to help the contractor. In this case NFSA doesn't really understand the hazards of flammable liquid fire protection(again, personal opinion).

DC was a day trip so not a lot of sights. I found most everyone to be nice in the Crystal City area. Downtown Arlington was another story.

And since your wife is looking in the hill country area, check the area around Bastrop and Kyle. New communities and this is an area with a great deal of growth. If you want an Austin realtor I have a great one. Plus, we have one of the strongest SFPE chapters in the US (160 + members) who host really good seminars. Aww, what the heck, come to Austin. We may be a little more expensive but the quality of life is much better. I suggest South Austin - easier pace than North Austin and less expensive.

 

[cdafd]

scott can you reply to two items
1. do you feel a normal fd has the equipment and training to support a high demand system if the ug to the sprinkler system is shut off but you still have working hydrants.

2. set ups that can rob the sprinkler system when the fire truck is hooked up to near by hydrants.

 

[stookeyfpe]

1)If the firefighters bring their brains to work. Like I've said, there is a full moon every third day and it is when B shift comes to work.

2) I don't understand what you are asking.

 

[cdafd]

Because of some of the ways the ug mains are set up that have fire hydrants and sprinkler systems off of the same main the fire truck draws the pressure that should be going to the fire sprinkler system. would say mainly on private mains.

 

[LCREP]

If you have one FDC after the city curb box and check valve feeding a private main around the building, then the FD should feed the FDC with a public fire hydrant. They should NOT connect to any of the private yard hydrants with a pumper. They will need to stretch hose from the next public fire hydrant to the site. Remember the sprinkler design only allows 250 gpm ( ESFR) or 500 gpm other warehouse occupancies for the FD hose lines. If they use more then this they will start to steal water from the sprinkler system. IF the building is gone when they pull up, then by all means use all the private fire hydrants to surround and drown.

FD should understand NFPA 13E, Fighting Fires in Sprinklered Buildings. A pre-fire plan would also help in this situation.

I agree the FDC and pipe should be sized for the maximum flow of the sprinkler system. I do NOT agree with NFPA 13. If we have an electric fire pump and we loose power, how is the FD going to feed the sprinkler system if it needs 1500 gpm at 140 psi to control and extinguish the fire!

 

[cdafd]

LCREP

thanks for the reply that is what I was asking. I agree somewhat with the idea of enough fdc's to supply the system, but not sold on it. I have seen it done a number of times. need to admend the local code to require it and makes it a little easier.