Class II Standpipe How many stations to calc?

[Oremus]

I've got a dedicated fire pump feeding a Class II Standpipe system w/ 1 1/2" hose stations. There are 2 standpipes fed from a common supply. I need some clarification on how many stations to calc.

From reading NFPA #14 my first guess would be (2) one at each standpipe. NFPA #14 7.10.2.2.1 reads, "Hydraulic calculations and pipe sizes for *each* standpipe shall be based on providing 100 gpm..." But 7.10.2.1.2 states, "Additional flow shall not be required where more than one hose connection is provided." So, is this implying that only 1 station is required to flow the 65 psi @ 100 gpm?


...and then there is 7.10.2.2.2, "Common supply piping serving multiple standpipes shall be calculated and sized to provide 100 gpm." To me this sounds like even if you're only flowing one hose station at the remote standpipe that any others will require 100 gpm in the common line - so in effect you're calculating two stations.

Class II Standpipes are not that common - anyone have any guidance?

 

[stookeyfpe]

Based on the most current edition of NFPA 14, Section 7.10.2.2.1 requires the calculation be based on a flow of 100 GPM. The residual pressure is 65 PSIG based on the requirement in Section 7.8.1. You only need to calculate the most hydraulically remote Class II hose connection.

One would not anticipate multiple Class II standpipe hose stations to be operated simultaneously and the NFPA 14 standard agrees with that assumption.

Personally, I wish we could just get rid of Class II hose connections. They are never maintained and are a hazard to the building occupants. Sorry for the rant.

 

[Oremus]

Thanks Stookey!