Okay, I'm really confused. In NFPA 13HB - 2013, I found the following: FAQ: Can nonmetallic pipe be used in an ordinary hazard occupancy? Nonmetallic pipe is not permitted in ordinary hazard occupancies and is only permitted in specific small ordinary hazard rooms within light hazard occupancies. The limitation to rooms that do not exceed 400 ft2 (37 m2) recognizes that almost all buildings have typically small storage rooms or mechanical rooms that would be categorized as ordinary hazard. Requiring a change in pipe type for those rooms or requiring the entire system to use metallic pipe would be overburdensome.
Supplement 3: (8)* Sprinklers shall not be required to be installed within electrical equipment, mechanical equipment, or air handling units not intended for occupancy. A.8.1.1(8) Equipment having access for routine maintenance should not be considered as intended for occupancy. Clarifies that some electrical equipment is large enough to be accessed by man doors. In these instances, where this equipment is not occupied but rather accessed for maintenance, sprinklers are not required. So, my three questions now are: 1. do I need sprinklers in the mechanical room that is 750 sqf? 2. what code identifies the mechanical room as OH1? 3. if I do need sprinklers, can I design the OH1 area off the cross main that feeds the light hazard areas (using only one riser feed)? Best Regards, John Allen, CET, CFPS President AFS: Allen Fire & Security Your Safety is Our Success Direct: 770.715.7261 | Office: 770.723.7280 Ext 2 | Fax: 678.894.4180 Please consider the environment before printing this email This email contains proprietary and confidential material for the sole use of the intended recipient and is the sole property of AFS. Any review, use, distribution or disclosure by others without the permission of the sender is strictly prohibited. If you are not the intended recipient (or authorized to receive for the recipient), please contact the sender by reply email and delete all copies of the message. -----Original Message----- From: Sprinklerforum [mailto:[email protected]] On Behalf Of [email protected] Sent: Wednesday, May 6, 2015 8:56 AM To: [email protected] Subject: RE: Light & OH1 Hazard From Same Riser You are looking for permission? How long could the possible scenarios in that list be? There is no restriction or prohibition of designing systems of different densities off one riser. It's common practice. Calculate and prove it works and you're done. Mechanical rooms contain rotating electrical equipment, some may contain natural gas or propane piping, or fuel oil, typically there's at least one or more boxes of filters since they go with the AC equipment, we will at some time probably have to consider the refrigerant being used on HVAC equipment as some of the "greener" gases have flammability properties. So HVAC mechanical rooms are not without hazards. OH 1 is typical for anything bigger than an apartment closet mechanical room. Craig L. Prahl Fire Protection Group Lead CH2MHILL Lockwood Greene 1500 International Drive Spartanburg, SC 29303 Direct - 864.599.4102 Fax - 864.599.8439 CH2MHILL Extension 74102 [email protected] -----Original Message----- From: Sprinklerforum [mailto:[email protected]] On Behalf Of Brad Casterline Sent: Tuesday, May 05, 2015 6:14 PM To: [email protected] Subject: RE: Light & OH1 Hazard From Same Riser Apology accepted ;) a real head-scratcher--- i thought of a few things, looked them up, and by golly they were not codes that allows you to design that way (the way we all do all systems that is) i'm going home and let this bother me all night... thanks (i cant wait til tomorrow morning when i check my mail) brad -----Original Message----- From: Sprinklerforum [mailto:[email protected]] On Behalf Of Jack Carlson Sent: Tuesday, May 05, 2015 4:51 PM To: [email protected] Subject: RE: Light & OH1 Hazard From Same Riser John, You should not have an issue with the design as described. Light and ordinary are commonly mixed, no separate supply main is necessary. Jack W. Carlson, SET Triple "A" Fire Protection Office - 251.649.2034 Fax - 251.649.2037 Cell - 706.247.5050 -----Original Message----- From: Sprinklerforum [mailto:[email protected]] On Behalf Of John Allen, CET, CFPS Sent: Tuesday, May 05, 2015 5:38 PM To: [email protected] Subject: Light & OH1 Hazard From Same Riser I apologize for such a simple question, but I would greatly appreciate some guidance: I have a 22,000 sqf light hazard office space with a 750 sqf mechanical room that I've identified as ordinary hazard 1. The entire ceiling space is an open 14' concrete beams and roof deck, and the mechanical room is separated by sheetrock and self-closing doors. The riser is in the mechanical room and I have 7 upright sprinkler heads fed off the cross main pipe feeding the light hazard office space. What code allows me to design this way or must I create a separate riser feed for each hazard? Best Regards, John Allen, CET, CFPS President AFS: Allen Fire & Security Your Safety is Our Success Direct: 770.715.7261 | Office: 770.723.7280 Ext 2 | Fax: 678.894.4180 _______________________________________________ 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 _______________________________________________ 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 _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
