Isn't it just like room design method and number of heads in a corridor? I'd argue on the rack question the code is silent because they didn't consider the situation not because they evaluated tests and deemed no difference. Had there been no difference don't you think the committee would have said that wet and dry are the same in that respect? Even at least an annex item? So the fact the standard doesn't tell us doesn't mean we shouldn't do it in these cases? Or at least make an engineering judgment? I can see in offices and corridors not worrying about what is probably a really short delay. In HPS or room design in high challenge fire I'm a little more worried.
Chris Cahill, PE* Senior Fire Protection Engineer, Aviation & Facilities Group Burns & McDonnell 8201 Norman Center Drive Bloomington, MN 55437 Phone: 952.656.3652 Fax: 952.229.2923 [email protected] www.burnsmcd.com Proud to be one of FORTUNE's 100 Best Companies to Work For *Registered in: MN -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Steve Leyton Sent: Thursday, May 31, 2012 1:23 PM To: [email protected]; [email protected] Subject: RE: dry-pipe with in-rack/ceiling protection of Class IV to > 25 ft in open racks Interesting questions yes, but the standard talks only about the # of levels of protection, not the gross area of the design overhead. Steve Leyton -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of ParsleyConsulting Sent: Thursday, May 31, 2012 11:19 AM To: [email protected] Subject: Re: dry-pipe with in-rack/ceiling protection of Class IV to > 25 ft in open racks Scott, I think Scot Deal raised an interesting question. He's correct in the increase in area of 30%, per 12.5.1, but the question remains, if we have in-rack sprinklers, do we increase the number of them flowing in a dry system calculation? If so, why? If not, why not? The table Scot referenced doesn't allow the use of CMDA sprinklers without in-racks as well, so what do we do about the number flowing in the calc? Anyone have input on the answer? PARSLEY CONSULTING Ken Wagoner, SET 760.745.6181 voice 760.745.0537 fax [email protected] <mailto:[email protected]>e-mail www.ParsleyConsulting.com <http://www.ParsleyConsulting.com>website On 5/31/2012 10:13 AM, Scott A Futrell wrote: > Scot, > > I don't see anything that sends you back to 11.2.3.2.5 to increase the > in-rack design requirement by 30%. 11.2.3.2.5 is an area of sprinkler > operation increase, not a number of design sprinklers increase. > Intuitively, yes. Prescriptive, no. > > Scott Futrell > > (763) 425-1001 x 12 Office > (612) 759-5556 Cell > > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of å... .... > Sent: Thursday, May 31, 2012 11:50 AM > To: [email protected] > Subject: dry-pipe with in-rack/ceiling protection of Class IV to> 25 > ft in open racks > > 2010 NFPA 13 > > When one uses dry-pipe with combination in-rack/ceiling sprinklers to protect > Class IV to greater than 25 ft per Table 16.3.1.1, the 30% increase applies > to both in-rack and overhead sprinklers, yes? > > scot deal > excelsior fire > -------------- next part -------------- An HTML attachment was > scrubbed... > URL:<http://fireball.firesprinkler.org/mailman/private/sprinklerforum/ > attachments/20120601/1810b32c/attachment.html> > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > > _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
