The chapter three reference is a definition of a system riser. The chapter eight references have to do with connections to a riser of standpipe in a combo system for floor control. The control valve is so you can isolate and drain a floor without shutting down the entire system and the check valves are so you can drain the riser or standpipe without having to drain or shut down every floor.
On Wed, Jan 21, 2015 at 8:42 AM, <[email protected]> wrote: > Consider NFPA 13 (2013) as the applicable standard. > > Question - Why are check valves required on each sprinklers system riser > when buildings are over 2 stories in height but they are not required on > each system riser when the building is single story (ex: warehouse with > multiple systems on a manifold)? > > Please assume for this question each system will have a DCBFP device > between the city water connection and the building. Also please assume the > FDC (with check valve) is tied directly into the manifold/standpipe > downstream of the DCBFP and prior to any system control valves. > > My code references are as follows: > 3.5.12 System Riser - The aboveground horizontal or vertical pipe between > the water supply and the mains (cross or feed) that contains a control > valve (either directly or within its supply pipe), pressure gauge, drain, > and water flow alarm device. > 8.16.1.5.1 - Multistory buildings exceeding two stories in height shall be > provided with a floor control valve, check valve, main drain valve, and > flow switch for isolation, control, and annunciation of water flow on each > floor level. > 8.17.5.2.2(1) - Each connection from a standpipe that is part of a > combined system to a sprinkler system shall have an individual control > valve and check valve of the same size as the connection. [This is > identical to NFPA 14 (2013) - 6.3.5.1] > > What I do not understand is why check valves would be required on each > system riser when you go vertical, but not horizontal. Any clarity on this > question, specifically "WHY" would be greatly appreciated. > > Thanks, > Sean > > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org > -- Ron Greenman Instructor Fire Protection Engineering Technology Bates Technical College 1101 So. Yakima Ave. Tacoma, WA 98405 [email protected] http://www.bates.ctc.edu/fireprotection/ 253.680.7346 253.576.9700 (cell) Member: ASEE, SFPE, ASCET, NFPA, AFSA, NFSA, AFAA, NIBS, WSAFM, WFC, WFSC They are happy men whose natures sort with their vocations. -Francis Bacon, essayist, philosopher, and statesman (1561-1626) A problem well stated is a problem half solved. -Charles F. Kettering, inventor and engineer (1876-1958) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
