I would think in combined systems 14)7.12.3 would apply and probably be the
greatest demand.  
Tom


This is kinda' embarrassing since I represent AFSA on the NFPA 14 TC.
Section 7.12.3 requires an inlet for every 250 GPM; NFPA 13 doesn't.
Nonetheless, I stand by my comments regarding practical applications and use
of FDC inlets ...

Steve Leyton

I'm sure they might sometimes try to put two hoses on a single clapper body,
but the main asset of that configuration is the option of using one or the
other inlet in case the attachment angle is better, or more convenient or
one of the inlets is obstructed, broken, etc.    Let's all keep in mind that
the "requirement" that an inlet be provided for every 250 GPM of demand
doesn't exist in the standards - it's just an old "rump rule".   A helluva
lot more water than 250 GPM can be pumped into a 2 1/2" outlet, that's for
sure; the newer mains here in SoCal often flow 1,500 GPM OUT of a single 2
1/2" hydrant port.   

With higher demand sprinkler systems and for multiple standpipes, it's
certainly a good practice to provide 4-way and even 6=way inlet manifolds,
where multiple hoses and much higher flow rates would definitely be of
value.   But if the FD is trying to pump more than 500 GPM into a light or
ordinary hazard system with a single-clapper 2-way FDC, chances are that the
fire has overpowered the system and they should be pulling back to watch the
water circus.

Steve Leyton

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