Although aware of the difference, I Have not studied the initial tests that lead to the findings. Despite leaps of logic sending us over an occasional cliff (aka reasons for water velocity limits) me thinks it is safe to assume that the mass to surface area ratio for garments hanging on a rack (since piled in a carton isn't a problem) pushes you outside the normal definition used for a typical NFPA 13 class III commodity (or IV for synthetics) plus the storage arrangement is a tad different than your standard load in a rack.
Nonetheless, knowing there is a difference DEMANDS that we not play ostrich and avoid sticking our heads in the sand and blindly assign the definitions from NFPA 13. Roland On Jan 6, 2010, at 1:45 PM, David Bitton wrote: > Hello, > > > > I am developing the protection criteria for a warehouse for hanging > garments > on typical pipe racks and wondering about the huge discrepancy > between the > requirements of FM Data Sheet 8-18 and NFPA 13 (I found nothing in > NFPA 13 > that prevents me from treating this as a Class IV rack storage with > 4 ft. > aisles). As an example, for 12 ft. storage, one option in the FM > Data > Sheet is a density of 0.60 gpm/sq. ft. over 3,500 sq. ft. whereas > for a > Class IV Commodity, NFPA 13 calls for 0.31 gpm/sq. ft. over 3,000 > sq. ft. > using high temperature heads. Does anyone have any insights to > explain the > huge discrepancy between these requirements? > > > > David Bitton, Eng. > > Quest Loss Control Services Inc. > > Les services de prévention des sinistres Quest inc. > > 5100, rue de la Savane, Suite 200 > > Montréal, QC H4P 1T8 > > Tel.: (514) 341-4545 Fax: (514) 341-8228 > > www.questlosscontrol.com > > > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.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 [email protected] http://fireball.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)
