NFPA fire tank sizing.
NFPA fire tank sizing.
(OP)
I am currently trying to find a section in the NFPA codes that roughly states, that if your fire tank size is not sufficient to provide for 100% of the demand then you can have a reduced tank size but need to have an increased water inlet to the tank.
Could someone tell me exactly which NFPA and what section of that specific NFPA this is?
Thanks a lot.
Could someone tell me exactly which NFPA and what section of that specific NFPA this is?
Thanks a lot.





RE: NFPA fire tank sizing.
Let's say that your water supply can only deliver 500 gpm, and you have a 1000 gpm sprinkler demand. You can have a tank that will supply 500 gpm for your water supply duration. You will need to have an automatic float valve on the tank so that it is automatically being filled by the public water line. I have seen these in rural areas, and also in systems where we have a very high static and very low residual pressure.
Travis Mack
MFP Design, LLC
www.mfpdesign.com
RE: NFPA fire tank sizing.
RE: NFPA fire tank sizing.
Here is what I found using Travis Mack's suggested keyword 'break tank':
To me, this suggests that the NFPA 20 standard doesn't explicitly state that break tanks can be used as water supply supplements to systems without a fire pump because it states by definition, break tanks provide suction to fire pumps, but that is a strict interpretation.
So then I went to:
My loose interpretation of this is that option (3) isn't constrained to only fire pump situations, in case your system isn't using one this would be vital.
My opinion is that you should take this information to the AHJ, along with the equivalency clause below, which you can use to argue that even though break tanks may be defined to be used for fire pumps only, it's the same concept without a fire pump:
If all of that goes smoothly, then you should take a closer look at NFPA 22 Standard for Water Tanks for Private Fire Protection, 2008 Edition as well as these sections in NFPA 20 Standard for the Installation of Stationary Pumps for Fire Protection, 2010 Edition:
RE: NFPA fire tank sizing.
Travis Mack
MFP Design, LLC
www.mfpdesign.com