THere is a difference in the methodology but it isn't density. As we all know 13 assigns the dimension along the branch line for the remote area based on 1.2 times the Sq Rt of the size of the remote area whereas FM has a longer dimension of 1.4, I think (having a senior moment)
Roland On Jun 29, 2009, at 3:22 PM, George Church wrote: > If I confused you, we're even now. > > glc > > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Chris > Cahill > Sent: Monday, June 29, 2009 5:40 PM > To: [email protected] > Subject: RE: FM rounding and other changes > > Except 13 is the predominant legal standard in the US. FM can do > whatever > they want but no where that I know of are they the legal standard. > > Perhaps you said that in your 3rd paragraph but where would FM > exceed 13 but > only need 2" lines vs. 2.5"? Do you mean to say FM has a higher > density > than 13 but rounding mathematically you get 2" lines and when you > recalc per > 13's lower density and rounding up you end up with 2" lines? Does > this > actually happen? Is this just a marketing trick by FM seeming to > require a > higher level of protection but in reality it's the same? Cynical I > guess. > > Chris Cahill, P.E. > Fire Protection Engineer > Sentry Fire Protection, Inc. > > 763-658-4483 > 763-658-4921 fax > > Email: [email protected] > > Mail: P.O. Box 69 > Waverly, MN 55390 > > Location: 4439 Hwy 12 SW > Waverly, MN 55390 > > > _______________________________________________ > 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)
