On a combination Class I standpipe/sprinkler riser with automatic standpipes, what is your process to determine exactly where pressure reducing valves should be used?
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NFPA 20 permits the demand for a suppression system to be between 90% and 140% of a fire pump's rated capacity (NFPA 20-2019 4.10.1 and Annex A.4.10.1). The pressure demand must always be less than the pressure supplied by the pump's performance curve along this range.
Does this concept apply to standpipes? For instance, could a 750 gpm pump provide 1,000 gpm demand for standpipes since it would be running at 133% of its rated flow? If it can be done, is it good practice? Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe For standpipe hose connections within stairwells, does ADA (Americans with Disabilities Act) restrictions apply to the dimensions of hose valves coming off pipe?
ADA - 2010 Standard 307.2 Protrusion Limits. Objects with leading edges more than 27 inches (685 mm) and not more than 80 inches (2030 mm) above the finish floor or ground shall protrude 4 inches (100 mm) maximum horizontally into the circulation path. 307.3 Post-Mounted Objects. Free-standing objects mounted on posts or pylons shall overhang circulation paths 12 inches (305 mm) maximum when located 27 inches (685 mm) minimum and 80 inches (2030 mm) maximum above the finish floor or ground. In particular, I'm wondering if the 4" protrusion limit applies to standpipe hose connections off of a vertical standpipe, and if it does, if it only applies if the standpipe hose connection is pointed into the path of egress? I would imagine there's some life safety experts that could explain this better than I surely am. Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe For years on my code calls I have asked the Authority Having Jurisdiction what the maximum distance the nearest hydrant is allowed to be away from a building's fire department connection. I get answers that range from 50 feet to 400 feet or even more.
I was looking into the code basis behind this question, and the only applicable section that I found is the International Fire Code, Section 507.5.1.1 that addresses hydrant locations for standpipe systems: "Buildings equipped with a standpipe system installed in accordance with Section 905 shall have a fire hydrant within 100 feet (30 480 mm) of the fire department connections. Exception: the distance shall be permitted to exceed 100 feet (30 480 mm) where approved by the fire code official." Is there any relevant requirement for hydrants near fire department connections for sprinkler-only systems? Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe NFPA 14 requires standpipes to be full flow tested for the acceptance testing.
Automatic standpipes are fairly straightforward to test, but how have you seen this applied for manual standpipes in mid-rise buildings? Is this a worthwhile test that will uncover design/installation flaws? Also, is there any compromised method to meet this requirement? Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe |
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