No, if you use the rules in 13 for horizontal and vertical distances in relation to the beam or obstruction it is as if the beam wasn't there. You still need to follow normal head spacing and deflector distance below deck rules but if you can drop the head down and off the beam enough to comply with the Table in 13 you'd treat it like a wide open space.
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 Cliff Whitfield Sent: Tuesday, February 09, 2010 8:49 AM To: [email protected] Subject: RE: Beam obstruction rules George & everyone, I guess I made this more complicated than it is. This guy basically thinks that even when you locate the head so that it is in compliance with the beam rule table and the beam does not block the discharge of the head, you still treat the beam as if it were a wall and you can't space the head on the other side of the beam more than 7'-6" off of the beam. Does this seem correct to you? In my opinion, once you meet the beam blocking rule, the beam does not exist in terms of head layout and spacing. Am I way off base here? Cliff -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of George Church Sent: Tuesday, February 09, 2010 4:44 AM To: [email protected] Subject: RE: Beam obstruction rules Spot on- and why we have prescriptive codes to apply- you did- he nneds to understand you comply and that's it, absent clear and present danger, contractual obligations... glc -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Ed Kramer Sent: Monday, February 08, 2010 6:38 PM To: [email protected] Subject: RE: Beam obstruction rules Let me guess: he doesn't have an issue with sprinkler spray obstruction, but has an issue with heat flow getting to the sprinkler. Assuming that's the case, he may (or may not) have a point - your beams are 15" deep and heat would more likely flow parallel to the beams rather than cross under the beam & fuse the sprinkler. To my knowledge, 13 doesn't address that. Unless someone wants to do some fire modeling, it's all opinion and theory. Ed Kramer Littleton, CO > -----Original Message----- > From: [email protected] [mailto:sprinklerforum- > [email protected]] On Behalf Of Cliff Whitfield > Sent: Monday, February 08, 2010 4:02 PM > To: [email protected] > Subject: RE: Beam obstruction rules > > Todd, > > There are no lights or fans or ducts that would create an issue. The > deflector is 6" below the deck so I only have 9" to worry about. I'm > trying to not say exactly what this guy has said so that I can get > other opinions before I influence anyone's answer. > > If anyone else wants to throw in their two cents, that would be great. > > Thanks, > Cliff > > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Todd > Williams > Sent: Monday, February 08, 2010 3:59 PM > To: [email protected] > Subject: Re: Beam obstruction rules > > How far down is the deflector from the deck? Any lights/ceiling fans > that could be in the way? > > > At 04:39 PM 2/8/2010, you wrote: > >Forum, > > > >I have a question regarding beam obstruction rules for standard spray > >uprights. > > > >I have a light hazard project that has 15" deep beams. The first > >beam > is > 9' > >from the wall and the next beam is 17' away from beam #1. If I space > my > >first head 5' away from beam #1 so that it is not an obstruction (per > table > >8.6.5.1.2-NFPA 13, 2007 ed), can my next head be 15' from head #1? > This is > >not supposed to be a trick question but I have a disagreement with an > FPE > on > >this. > > > >Thanks for your insight on this one. > > > >Cliff Whitfield, SET > >President > >Fire Design, Inc. > > > >[email protected] > >www.fire-design.com > > > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > > For Technical Assistance, send an email to: [email protected] > > To Unsubscribe, send an email to:Sprinklerforum- > [email protected] (Put the word unsubscribe in the subject > field) _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.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 [email protected] http://fireball.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 [email protected] http://fireball.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 [email protected] http://fireball.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)
