Combined System Riser - supply more than one? 2

[pipesnpumps]

"7.1.3 Auxiliary Systems. A wet pipe system shall be permitted to supply an auxiliary dry pipe, preaction, or deluge system, provided the water supply is adequate."

With "AN" being the key word, how have you guys seen this interpreted?

Does that mean only one is allowed, or could you supply more than one auxiliary system off a wet pipe system?

I've got a situation where there are a smattering of server rooms, separated located, in a large business occupancy facility, and user wants single interlock preaction sprinklers in them. Going back to a water supply would require many hundreds of feet (and maybe a new UG lead-in?).

I think I know the answer is "there can only be one", but I was wondering if anyone thinks two or more is ok.




Real world knowledge doesn't fall out of the sky on a parachute, but rather is gained in small increments during moments of panic or curiosity.

 

[SprinklerDesigner2]

You can have as many as you want.

You have a wet system with three loading docks each needing a small auxiliary dry pipe system. No problem as long as the total system doesn't exceed 52,000 sq. ft. (assuming it is not Factory Mutual and light/ordinary hazard).

I bring up Factory Mutual because they'll accept systems covering far more than 52,000 sq. ft..

 

[TravisMack]

I agree with SD2. You can have as many of these "auxiliary" systems coming off of a wet system as long as you stay within the system area limitations.

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

 

[SprinklerDesigner2]

Travis,

It is with breathless anticipation I am waiting to design my first FM system exceeding the NFPA area limitations. I've done several FM jobs lately but all dry systems and no way am I going to go 100,000 sq. ft. on one of those.

 

[pipesnpumps]

Sweet, thanks! It only makes sense you can have more than one, but the wording was giving me pause.

Real world knowledge doesn't fall out of the sky on a parachute, but rather is gained in small increments during moments of panic or curiosity.

 

[TravisMack]

SD2:

I recently completed a "large" movie theater complex that was to be per FM guidelines. It worked out well because the bldg footprint was +/-60k sq ft. What benefit do you really get having a second system on a project like that? We ended up saving the contractor a few $$ by eliminating a riser on the project by being able to use the expanded system areas per FM.

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com