Look at section 7.3.2.1. (2007 ed) It states that dry pipe systems protecting dwelling units can not use the options in 7.2.3.3 (no time limit of water delivery when capacity is less than 500 gal) or 7.2.3.4 (no time limit of water delivery when capacity is less than 750 gal and a QOD is installed).
This is not a residential sprinkler issue but a dwelling unit issue even with spray sprinklers. This is the only restriction for a light hazard occupancy. Residential sprinkler can be part of a dry pipe system (the 15 sec is part of their listing and reasonable to assume their is a correlation well maybe better to say this was the source of the general requirement) This was further restricted in 2010 ed within the Calculated Timed option in 7.2.3.6 but saying water delivery must be with 15 seconds. Technically the was applicable only if you applied this option. This was better clarified in the 2013 ed where the option to apply the 60 sec rule was removed (for dwelling units) and the 15 sec water delivery requirement was moved to 7.2.3.1.1 as a general requirement. Bottom line, the standard states the system shall be wet pipe only in ch 12 - Storage and granted that 8.16.4.1.1 implies the same requirement by saying when subject to freezing it shall be a dry-pipe system. Actually it’s not an exception to wet pipe but a requirement for freezing conditions so no restriction there for normal conditions. So without there being something else that I can’t remember (a distinct possibility) nor find, there is nothing that forbids dry pipe in light hazard occupancies but the text for a subset of LH supports it use in all LH occupancies. Roland Roland Huggins, PE - VP Engineering American Fire Sprinkler Assn. --- Fire Sprinklers Saves Lives Dallas, TX http://www.firesprinkler.org On Feb 21, 2014, at 7:05 AM, Steve Mackinnon <[email protected]> wrote: > Good morning all, > > I have a Local AHJ that is saying in NFPA 13, 2007 edition it states that dry > systems are not allowed in light hazard applications, does anyone have an > idea of where this is located?? I've looked through the standard a few times > and can't put my finger on anything close. > > Thanks in advance > > Steven > > Steven MacKinnon > Fire Protection Division > Hartcorn Plumbing and Heating, Inc. > 850 South Second Street > Ronkonkoma, NY 11779 > Office 631-580-2300 Fax - 631-580-1090 > > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
