I don't know if that extra 250 lbs was really for the fitter of old to grab onto or if that is just the story we've been telling each other for so long it's become the common "truth." If the truth then we'd better reassess it in light of current times. First we need to add about 100 lbs if it's to meet the criterion of the story but, and probably more telling, I think OSHA (or your local version) might be concerned if we're actually telling our fitters to grab the piping if they fall. Adding the 250 lbs is the rule. Why is unimportant unless the hanging and bracing committee wants to revisit the rule. If research were to suggest that the "story" really is the "truth/reason" then maybe we can just let it go. And what really is the criteria for any of this? Is it just a left over from the days of "I remember when 13 fit in your back pocket" versions of 13 that only addressed pipe schedules and other good, safe rules of thumb? Who decided, when was it decided, why is it (has it been constantly evaluated as valid--too much or too little), what values is it based on, etc.? In any event at this stage of sprinkler design development I'd worry about adding the 250 lbs to the calculation but not because a fitter might grab it. He might just as easily reach out for the 1/2 inch conduit. Better to have him properly tied off. Saves a heap of change on OSHA fines, lawsuits and possible criminal charges.
On Tue, Aug 4, 2009 at 8:09 AM, Todd Williams<[email protected]> wrote: > Something to think about. Hangers are designed to take 5x wt of water > filled pipe +250 lbs. The 250 is supposedly to support a fitter if he > had to grab on to it in an emergency (or so I have been told). Has > anyone looked into if CPVC pipe could support a 250 lb person, even > with hangers designed for it? > > > > At 10:54 AM 8/4/2009, you wrote: >>Why not just calculate the modulus using the methods in NFPA 13 and then >>size your trapeze pipe accordingly. Or, as George said, use the values >>for steel and just have some oversized trapeze bars. >> >> > Assuming CPVC weighs less than steel pipe, use values for steel and you're >> > safe. If you're near a head, make sure you're protecting against upward >> > movement if needed. >> > >> > When we get into bar joist construction, we often switch to steel since >> > hanging issues often make it a better installation all around. >> > >> > glc >> > >> > -----Original Message----- >> > From: [email protected] >> > [mailto:[email protected]] On Behalf Of >> > [email protected] >> > Sent: Tuesday, August 04, 2009 9:03 AM >> > To: [email protected] >> > Subject: Re: trapeze hanger, PVC >> > >> > Greg, >> > If you are in a position to require trapeze hangers on cpvc,maybe you need >> > to reconsider using steel pipe for stability and rigidity.Just a thought. >> > ---- Greg McGahan <[email protected]> wrote: >> >> Have we ever discussed the use of trapeze hangers for cpvc piping? >> > Specifically, modulus requirements etc? >> >> >> >> Greg McGahan >> >> Operations Manager >> >> >> >> Living Water Fire Protection >> >> 1160 McKenzie Road >> >> P.O. Box 877 >> >> Cantonment, Florida 32533 >> >> (850) 937.1850 | Fax (850) 937.1852 | Cell (850) 554.3231 >> >> [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) >> > >> >> >>-- >> >> >>_______________________________________________ >>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) > > Todd G. Williams, PE > Fire Protection Design/Consulting > Stonington, Connecticut > www.fpdc.com > 860.535.2080 > _______________________________________________ > 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) > -- Ron Greenman Instructor Fire Protection Engineering Bates Technical College Tacoma, WA Member: SFPE, ASCET, NFPA, AFSA, NFSA AFAA _______________________________________________ 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)
