Rahe, An starting point error on my part since you did refer to 8.15.19.5 but your argument against the 1/2 inch nipple method sent me to 8.15.19.4 which is the only place it is allowed. And if you have someone arguing 8.15.19.4 in an 8.15.19.5 situation then the argument would be vacuous. The allowance is for known and later build-out so that a 1"x lesser outlet size bushing can be installed with a head directly attached to the bushing. (in the pre ISO model this could have been stated and was much simpler by an exception that stated you can't put a head in a bushing except under these particular conditions). So the 1/2" or 3/4" x 4" nipple to transition from a branch line outlet to a drop in an existing pipe schedule system not in a seismic zone is still allowed (in at least through the 2007 edition) if it can be hydraulically proven to work (improvements added since the original version are the disallowance in seismic zones and the requirement top calc and prove the change). The allowance for future known but undefined at time of shell construction improvements/changes is to allow the attachment of heads directly to bushings if necessary.
On Sat, Mar 27, 2010 at 9:24 AM, Ron Greenman <[email protected]> wrote: > Since it's only applicable to pipe schedule systems, which are way > overbuilt anyway, and now has to be hydraulically demonstrated to > work, and cannot be used in seismic zones where strong lateral loads > could cause the small piping to fail, and that it allowed, how can you > say it is, "a poor substitute for doing it correctly?" It allowed it > is correct. If my opinion is light hazard is a poor substitute for > doing it correctly I will lose all light hazard bids if I bid to an > ordinary hazard. If Tukwila, WA decides that light hazard is a poor > substitute for doing it properly and codifies that then light hazard > not only is a poor substitute but not even a substitute that can be > considered. I have no problem with us changing code through process > but I really have a problem with individuals, be they engineers or > local AHJs just having an opinion without data. It costs people money. > If your opinion can be demonstrated to be better then submit your > change, along with data supporting your argument, and get the code > changed properly. The law of gravity is not a political opinion > subject to the beliefs subject to the whim of the witch doctor > representing a local tribe. Disclaimer: This is a hot button with me > and I'm not busting your chops or any other individual directly but I > can't abide statements that scoff at established and proven viable > methodologies without supporting data. Do we work to sound engineering > practices and empirically proven outcomes or opinion. If the later we > are not scientists but religionists and ought to return to a earth > centric universe with little LEDs twinkling in the crystal sphere > holding up the stars. > > On Sat, Mar 27, 2010 at 9:06 AM, Ron Greenman <[email protected]> wrote: >> Rahe, >> >> Look to the quote in my post of late last night referring to 13/2007 >> edition. It's still there. You need to go further into 8.15. Your >> looking at new build-out stuff for shell structures (typically strip >> malls) whereein the tenant layouts will not be known at time of >> construction but it is known there will be modifications. Here's the >> reference from 2007 again: >> >> The option is available only for pipe schedule systems only and is found >> in 2007:8.15.19.4. It's 8.15.19.4.3 that allows the nipples less than >> 1". "When it is necessary to pipe two [sic] ( I presume this is a typo >> and not a restriction to only two heads-my comment) new ceiling >> sprinklers from an existing outlet in an overhead system, the use of a >> nipple not exceeding 4 in. (100mm) in length and of the same pipe >> thread size as the existing outlet shall be permitted, provided that a >> hydraulic calculation verifies that the design flow rate will be >> achieved...." The arrangement is shown in figure 8.15.19.4.2 and >> clearly shows the nipple being of a lesser diameter than the drop and >> being attached to a labeled reducing elbow. 8.15.19.4.4 disallows >> using the arrangement in earthquake country. >> >> On Sat, Mar 27, 2010 at 8:56 AM, Jay Jay Blocker >> <[email protected]> wrote: >>> Would this same idea be considered acceptable if a 1/.2 inch nipple was >>> used to go from the attic (1x1x1/2) through a celing with a 1/2 inch by 4 >>> inch nipple that connected to another 1x1x1/2 t that supplied two >>> uprights? Just wandering since it is in a system less than a year old. >>> >>> J. Blocker >>> EFPS >>> (303) 353-9712 >>> >>> >>> >>> >>> ________________________________ >>> From: tom poisal <[email protected]> >>> To: [email protected] >>> Sent: Sat, March 27, 2010 9:22:47 AM >>> 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) >>> >> >> >> >> -- >> Ron Greenman >> Instructor >> Fire Protection Engineering >> Bates Technical College >> Tacoma, WA >> >> Member: >> SFPE, ASCET, NFPA, AFSA, NFSA AFAA, NIBS, WSAFM, WFC >> > > > > -- > Ron Greenman > Instructor > Fire Protection Engineering > Bates Technical College > Tacoma, WA > > Member: > SFPE, ASCET, NFPA, AFSA, NFSA AFAA, NIBS, WSAFM, WFC > -- Ron Greenman Instructor Fire Protection Engineering Bates Technical College Tacoma, WA Member: SFPE, ASCET, NFPA, AFSA, NFSA AFAA, NIBS, WSAFM, WFC _______________________________________________ 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)
