There was a proposal submitted to the committee during the last open cycle (2007 edition) where the submitter recommended changing the 52,000 sqft limitation to 150,000 sqft.
The proposal noted that 3 floors of 50,000 sqft each, with one control valve in permitted now - so why not permit the same area on one level. The submitter knew the committee wasn't likely to accept 150,000 sqft on a single control valve but thought something between 52,000 and 150,000 could be acceptable. (I spoke to the submitter and agreed with the logic) The proposal was rejectected without much discussion. As noted by Mr. Church, these limitations are intended to limit the area out of service at one time, as is the requirement for in-rack sprinklers to be separate from overhead systems. The origin of the rule corresponds to the maximum size a system could be with a pipe schedule system fed by an 8" lead-in. Bob Caputo ---- George Church <[EMAIL PROTECTED]> wrote: > There's been some priot threads on this topic related to # of heads on an 8" > pipe scheduled system and other items, speculatively; > However, the concept is to minimize the area that is impaired during any > maintenenace/repair/renovation. While it is scary enough for your insurance > carrier to accept the risk of 40,000 SF of warehouse and goods unprotected > while you shut down to add heads under a new mezzanine, it is certainly a > LOT riskier if 500,000 SF of it is impaired. > > glc > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Reza Esmaeili > Sent: Monday, September 17, 2007 8:46 AM > To: [email protected] > Subject: What is the reason of maximum coverage area protected by > onesprinkler system? > > Hi! > I don't know the reason of of limiting coverage area protected by one > sprinkler system. For example why should I determine maximum 52,000 sq.ft > for one sprinkler system in an ordinary hazard area? > imagine a 125,000 sq.ft factory which is an Ordinary Hazard Group II > occupancy with a design area of 1,500 sq. ft. and density of 0.20 gpm/sq.ft. > and 1sprinkler/100 sq.feet > Then the number of active sprinklers would be 15, and I should design 3 > wet pipe sprinkler systems. > My question is that while in a 125,000 sq.ft factory there are only 15 > active sprinklers, then only ONE riser with ONE alarm check valve can supply > the demand, so why NFPA needs 3 riseres with 3 alarm check valves? I think > the reason is not related to hydraulics. > One reason might be that one system can be out of service while other > systems are working, Is there any other reasons? > Thanks, > Reza > > > --------------------------------- > Catch up on fall's hot new shows on Yahoo! TV. Watch previews, get > listings, and more! > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > > To Unsubscribe, send an email to:[EMAIL PROTECTED] > (Put the word unsubscribe in the subject field) > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > > To Unsubscribe, send an email to:[EMAIL PROTECTED] > (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
