When all the lawyers are gone! And everything back to Hammurabi is repealed!! I've got things to lose and there are VERY few reasons for me to risk those.
Forum, no problem, we're all friends I've never met here, well except for a few. Chris -----Original Message----- From: Sprinklerforum [mailto:[email protected]] On Behalf Of Brad Casterline Sent: Tuesday, May 20, 2014 8:04 PM To: [email protected] Subject: Re: Area/Density Method and Walls Chris, I hope you meant for this to go to The Forum, not just me so I am trying my hand at re-directing it. Isn't it time we start seeing where semantics might be trying to over-ride physics? > On May 20, 2014, at 7:44 PM, "Cahill, Christopher" <[email protected]> > wrote: > > Trust me, my opinion is the same, damn near any wall will stop the heat flow > long enough to get the right heads to operate. This is strictly a code > question. I'm OK and good at separating Code from opinion or even reality in > many cases. Reality is wall will stop the heads on the other side for an > hour but Code seems to be silent. OK when the unrated steel holding up wall > falls in 15 minutes assuming the sprinkler don't actually operate reality is > the 1 hour wall falls in 15 minutes. OK the valve is open, sprinklers operate > and the wall never fails until the municipal water supply runs out so all > this is moot in the real reality. I sleep better following Code. > > Chris > > -----Original Message----- > From: Sprinklerforum [mailto:[email protected]] > On Behalf Of Brad Casterline > Sent: Tuesday, May 20, 2014 7:33 PM > To: [email protected] > Subject: Re: Area/Density Method and Walls > > The reason I ask Chris is, the calculation method sprung Not from "how fast > does an accidental fire get how hot", but "if we make the second piece inch > and a quarter can we reduce the main size a notch or two, and still get the > same water?" And I hear the first remote areas were round! I would consider > any barrier to the fire-driven heat flow, rated or not. > >> On May 20, 2014, at 7:17 PM, Brad Casterline <[email protected]> wrote: >> >> Good water or bad? >> >>> On May 20, 2014, at 7:12 PM, "Cahill, Christopher" <[email protected]> >>> wrote: >>> >>> I can't believe I'm asking this question after all these years. Anyway, >>> swallowing pride and asking. >>> >>> 2010 NFPA 13 strict Density/Area method 11.2.3.2 and 22.4.4.1.1. Great big >>> room being subdivided. Existing system with a new wall added between heads >>> on a BL. Contractor had to add a head on one side to preserve the existing >>> spacing (area) of the heads. Without head over 130 sq.ft. I take the 1.2 >>> ^.5 of the area and get 46.5' required along the BL. Original system lets >>> say calc'd 5 heads on the BL. But now in the same 46.5' there are 6 heads >>> on the BL. Do I ignore the wall and require a new calc? What if the wall >>> is rated 1 hour do I ignore it? >>> >>> I looked all over and can't seem to find anything definitive. Room design >>> is out so not a consideration. 22.4.4.1.1.1 simply says all the heads in >>> the 46.5'. I can't find anything that says either to count the wall as a >>> break so measure 46.5' from the wall in each direction and still see if >>> there are 5 head or ignore it and there are now 6 heads. I find 11.1.2 >>> that clarifies to extend the density or not. I don't think that's >>> applicable exactly. The question is not about whether to extend the density >>> on either side. Let's just say it's all OH. >>> >>> It gets a little more complex as on the one side of the wall they cut a >>> head in on the BL but on the other side there is a perpendicular new wall >>> and they come off same BL and arm over to two more head so if I ignore the >>> walls there are now 8 heads off the 1 BL. >>> >>> Prefer a code section or written reference 'cuz this is going to be a big >>> deal if we ignore the walls. Ordinarily with unrated walls they are >>> ignored in density/area (of course can't find that reference). I think I'm >>> getting tripped up with the rated portion? Or maybe I'm just tired???? >>> >>> Chris Cahill, PE* >>> Associate Fire Protection Engineer >>> Burns & McDonnell >>> Phone: 952.656.3652 >>> Fax: 952.229.2923 >>> [email protected]<mailto:[email protected]> >>> www.burnsmcd.com<http://www.burnsmcd.com/> >>> *Registered in: MN >>> >>> >>> Proud to be #14 on FORTUNE's 2014 List of 100 Best Companies to Work For >>> >>> >>> >>> >>> _______________________________________________ >>> Sprinklerforum mailing list >>> [email protected] >>> http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org >> _______________________________________________ >> Sprinklerforum mailing list >> [email protected] >> http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
