NFPA 13 2007 sets a min. temp for OH of 150'F but no maximum except to say intermediate or high temp are both ok. Notes: see 8.3.2.3 , 8.3.2.7 , 8.3.3.2 , A8.4 , 8.4.7.3.3
Maybe have the AHJ show where it prohibits have the two temps adjacent? Put a heater in a 165'f protected space and you could have several 286'F heads located near that heater, even in the summer time when the heater is off. Thom McMahon, SET Firetech, Inc. 2560 Copper Ridge Dr P.O. Box 882136 Steamboat Springs, CO 80488 Tel: 970-879-7952 Fax: 970-879-7926 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Chris Cahill Sent: Wednesday, June 17, 2009 11:59 AM To: [email protected] Subject: Temperature Rating '07 8.3.2 Rating and 8.3.3 Sensitivity I can find no place where is says what if anything should be done with different ratings in the same room (10,000 sq. ft. ish room). 8.3.3 clearly says when QR all in compartment must be QR. But in the temperature rating there is nothing like that. A.8.3.2.7 is close but only suggesting the high temps in high hazard go 30' beyond. So at 31' one could change back to ordinary temp. The situation is an existing space OH design (mini-storage) with 286 heads, in one bay (2 lines) heads are 165 heads. All standard response. There is a beam separating the two temperature different heads. The beam is 22" down from the clg. but the top 4" is open for the joist bearing. A competitor noted this temperature issue on an inspection as a deficiency. We were the last one in there doing work <6 months ago but not in this area. Fire Marshal wrote orders to the owner to fix based on inspection report. Owner is wanting us to fix it, presumable at our cost. But I don't see where this is a deficiency in the first place. We can have a discussion about whether it's a good idea or not but in the end the code seems to allow the mixing of heads temperatures. Yes skipping of heads at the interface is a potential issue. How much is a guess, me brain doesn't do CFD modeling. Yes it's easy to say just change out the heads and make them all high temp. We may do it but I am trying to establish all on the same page that this is perfectly CODE compliant then negotiate a fix if wanted. This is especially true when other sprinkler companies are involved and appear to be wrong. So anyone have a code reason this isn't allowed? Chris Cahill, P.E. Fire Protection Engineer Sentry Fire Protection, Inc. 763-658-4483 763-658-4921 fax Email: [email protected] Mail: P.O. Box 69 Waverly, MN 55390 Location: 4439 Hwy 12 SW Waverly, MN 55390 _______________________________________________ Sprinklerforum mailing list http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
