Agree, As a general guideline what is the branch line requirement per 9.3.6.3? In my previous example (by definition) this is a branch line, but I don't feel it truly needs a restraint. So what do we use as a general rule? I always went with my opinion that a branch line supplies more than one sprinkler, so in my example you wouldn't need a restraint but if you had a single sprinkler fed from a pipe 6'-0 long or longer coming from a main, common sense would say put one on that due to length. That's where I feel they need to put some kind of clarification as to pipes feeding single sprinklers - my opinions and common sense do not always match others, even fire marshals. But going back and adding or putting on unnecessary restraints can be costly.
Bobby Gillett Sr. Project Manager Key Fire Protection, Inc. (731) 424-0130 office (731) 424-9285 fax (731) 267-4853 cell [email protected] -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Thursday, July 23, 2009 8:17 AM To: [email protected] Subject: RE: Branchline/Restraint of Branchline Depends on just how technical you want to get. Based on the definition, the branch line serves multiple sprinklers. The 9.3.6.3 sounds like it's written more for a branch line where you've got uprights or pendant sprinklers connected directly to the branch line. (exposed construction?) This is supported when looking at the various illustrations within 13. So are we talking about a sprinkler drop or an actual branch line? The branch line support is defined in 9.2.3.4.1 (NFPA 13, 2007), armover is covered in 9.2.3.5 and sprigs in 9.2.3.7. If you look at sprigs for instance the restraint requirement applies if it's over 4 ft in length. This same criteria could be conversely applied to a drop to a sprinkler below. It's all up to the AHJ when it starts getting into these gray areas. Craig L. Prahl, CET Fire Protection Specialist Mechanical Department CH2MHILL Lockwood Greene 1500 International Drive PO Box 491, Spartanburg, SC 29304-0491 Direct - 864.599.4102 Fax - 864.599.8439 [email protected] http://www.ch2m.com -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Bobby Gillett Sent: Thursday, July 23, 2009 8:46 AM To: [email protected] Subject: Branchline/Restraint of Branchline A fitter asked us how long a branch line has to be before it requires end of the line restraint. A fire marshal told him he could never find an answer so they put in place 13ft or longer. 9.3.6.3 The end sprinkler on a line shall be restrained against excessive vertical and lateral movement. In my opinion, the way this is written, all branch lines are to have them, which brought up the next debate; 3.5.1 Branch Line - The pipes supplying sprinklers, either directly or through sprigs, drops, return bends, or arm-overs. Would a 1x1'-0 pipe coming from a main supplying a single sprinkler through a return bend (or any configuration) be a branch line, and if so would it require an end of the line restraint? The definition says a pipe supplying sprinklers so this would qualify because an arm-over is defined as coming from a branch line. If this is the case, I think a limit of length is required to be put on branch lines requiring end of the line restraint. Thank You, Bobby Gillett Sr. Project Manager Key Fire Protection, Inc. (731) 424-0130 office (731) 424-9285 fax (731) 267-4853 cell <mailto:[email protected]> [email protected] _______________________________________________ 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) _______________________________________________ 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)
