Number of sprinklers on a branch line?
Number of sprinklers on a branch line?
(OP)
I think there used to be a limit of the number of sprinklers on a branch line (say 8).
It may have been only for schedule pipe sizing.
I can't find the requirment in the current standards (NFPA 13 i.e. 2007).
Is it still there?
It may have been only for schedule pipe sizing.
I can't find the requirment in the current standards (NFPA 13 i.e. 2007).
Is it still there?





RE: Number of sprinklers on a branch line?
RE: Number of sprinklers on a branch line?
Use the skew formula to determine this. I have not checked for many years, but it should be in NFPA 13. Its 1.4 x square root of the remote area. Note: I believe NFPA is 1.4, and FM notes 1.2, but i will let you confirm that. For example if you have a 2,000 sq ft remote area, using this formula gives you 54 ft. If you are using 10 ft line spacing, you therefore can have a max of 5 heads per line.
For ESFR, you are limited to 4 heads per line. For the typical 12 head ESFR design area, it is therefore 4 heads on 3 lines.
This is important. Fires dont grow in one dimension. These rules make sure designers are applying remote areas that most closely resemble a someshat cirucular fire growth pattern.
RE: Number of sprinklers on a branch line?
There is a practical limit just due to the size of pipe that may be involved. But, NFPA 13 does not have a limit anywhere in the standard on the number of sprinklers per line.
Travis Mack
MFP Design, LLC
www.mfpdesign.com
RE: Number of sprinklers on a branch line?
RE: Number of sprinklers on a branch line?
Travis Mack
MFP Design, LLC
www.mfpdesign.com