Leyton just got into office - West Coast representin'! Yes, I think it's intended that there be two FHV's available for testing at an approved location - ideally the most remote (usually top) of one or more standpipes. Our practice is to furnish a two-way manifold at the top of all Class I standpipes, whether they are within a stair enclosure or free-standing on the roof.
WRT to the horizontal standpipe issue, I'm not sure and I think it's a great question. On the one hand, the 1000 GPM cap on sprinklered buildings rightfully presumes that there will be a controlled fire scene and hose streams will be secondary and mop-up. On the other hand, a horizontal standpipe is a completely different hydraulic model (at each floor) than if you took water from each of three FHV's that were independently supplied by two or three different risers. If you put a gun to my head, I'd say 1000 GPM cap on all sprinklered buildings, period. Rich? Steve Leyton Protection Design & Consulting The foregoing is the opinion of the writer alone, and does not necessarily represent the intent of the NFPA 14 Technical Committee, nor constitute a formal or informal interpretation of the standard. -----Original Message----- From: Ron Greenman [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 07, 2007 7:28 AM To: [email protected] Subject: Re: More NFPA 14 - 2003: Max Flow Horiz SP Sounds like 750 to me if a single pipe and up to 1250 on any common runs to multiple pipes. What's Leyton say? On 2/7/07, Fletcher, Ron <[EMAIL PROTECTED]> wrote: > In a fully sprinklered one story building what is the maximum flow for a > single Class I horizontal standpipe system with more than three (30 > actual) connections? 750 gpm, 1000 gpm or 1250 gpm. > > 7.10.1.1.3 The minimum flow rate for additional standpipes shall be 946 > L/min (250 gpm) per standpipe, with the total not to exceed 4731 L/min > (1250 gpm) or 3785 L/min (1000 gpm) for buildings sprinklered > throughout. > > 7.10.1.2.2 Where a horizontal standpipe on a Class I and Class III > system supplies three or more hose connections on any floor, hydraulic > calculations and pipe sizes for each standpipe shall be based on > providing 946 L/min (250 gpm) at the three hydraulically most remote > hose connections on the standpipe and at the topmost outlet of each of > the other standpipes at the minimum residual pressure required by > Section 7.8 > > 7.10.1.2.3 Common supply piping shall be calculated and sized to provide > the required flow rate for all standpipes connected to such supply > piping, with the total not to exceed 4731 L/min (1250 gpm). > > Ron Fletcher > Aero Automatic Sprinkler > Phoenix, AZ > > Aero Automatic Sprinkler > > PHoenix, AZ > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > -- Ron Greenman at home.... _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum
