I dug back in my old handbooks and found that in the 1985 and 1987 editions of NFPA 13 it actually stated sprinkler outlets and indicated the diameters of the nipples. Now NFPA 13 speaks to bushings, not sprinklers. It also speaks to providing drops to ceilings below. I would assume that this is not applicable to SSU's.
Rahe Loftin ----- Original Message ----- From: tom poisal [[email protected]] Sent: 03/27/2010 11:22 AM AST To: [email protected] Subject: Re: 1/2 inch nipple in sprinkler outlet Hey Guy's, really this is an approved method for upgrading an existing system, wherein SSU were to be replaced with SSP heads, however as it invariably goes, a space is rented, ceiling goes up and overhead system needs to be converted; gotta calc it, ref nodes at each change in pipe size.............as to Seismic Zones, I believe it does not pertain, sorry Ron; but if it is proven by hydraulic calculations (existing system upgrade talkin here) then I believe the above situation is within code. Thomas Poisal, CET On Fri, Mar 26, 2010 at 8:25 PM, <[email protected]> wrote: > Here is one that relies on an interpretation of the code from its literal > verbiage. NFPA 13: 8.15.19.5 states "When hydraulically designed systems > are revamped, > any existing bushing shall be removed and a nipple not exceeding 4 in. (100 > mm) in length shall be permitted to be installed in the branch line > fitting." This has historically been taken to mean that a 4 inch by 1/2 > inch nipple can be installed in an existing 1 X ! X 1/2 tee to provide an > armover for a pendent sprinkler to a ceiling below. > > However, this is not what the code states. NFPA 13 is relating to a > bushing that was installed in an unfinished space. In fact, it does not > state what size nipple is acceptable except that it cannot be less than 1 > inch if it is in an earthquake zone. As I read it, you cannot just remove > an upright sprinkler and install a 1/2 inch nipple connected to a 1/2 to 1 > inch increaser and drop it to the ceiling below. What is the consensus > and/or did the standard change sometime ago? > > Thank You > > Rahe Loftin, P.E. > Region 7 - GSA > Office - 817-978-7299 > Fax - 817-978-8644 > Cell - 817-371-3102 > > _______________________________________________ > 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]<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)
