Forum, My Thursday afternoon ramble. NFPA 13 (2013) - Table 17.3.3.1: why is there no outline for 22.4k @ 35ft storage w/40ft roof?
22k's are defined for 40ft/45ft, 35ft/45ft, 30ft/45ft, 30ft/40ft, and 30ft/35ft. All of which have an operating pressure of 40psi except the 35ft roof height which is 35psi. Other than that, I can't seem to find a difference between any of them. I would like to say I can safely assume the design for my 35ft@40ft building will be 40psi. Based on the fact that all the other surrounding storage height, roof height, and storage to roof clearances all say 40psi will work. Also, I back checked 16.3.3.1 which I have found typically mirrors the cartoned non-expanded plastics section of 17.3.3.1, and that section does have the 35ft/40ft described as 40psi. I checked 2007 and 2016 versions and they have this same missing definition. So what gives? And if your argument is just "they left it out because the 35ft/45ft roof covers it". Then I say "that's fine and dandy, but then why do they specifically spell out 30ft/45ft and 30ft/40ft when they are exactly the same protection". I hope I'm missing something or this was just an oversight and not just a matter of trying to save ink on the page. Thanks, Sean VG _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
