Scot and Thom are both right. ESFR design and installation has nothing to do with density. At 100 sq.ft. you have the same design as 64 sq.ft. thus density has nothing to do with ESFR. Scot is applying the science of ADD (actual delivery density) and RDD (required delivered density) and is correct if the ADD is less than the RDD the fire doesn't get controlled or suppressed.
Now Scot you also forgot a couple things in your list of two. Lots in it self is good but not the complete answer. Droplet size and velocity are a critical component in high challenge fires. You can throw an ESFR link in an SSP with lots of water and get spectacular failures where ESFR is successful because the drops are bigger and they spray down almost like a FF nozzle. 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 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of å... .... Sent: Tuesday, May 04, 2010 12:58 PM To: [email protected] Subject: boat storage do we think fires in group A plastics, bin-box storage-on-racks, are going to ignore whether a sprinkler is putting out 0.495 gpm/ft2 versus 0.97 gpm/ft2? I am sure the statement that "density has nothing to do with ESFR technology" was meant in some connotation that is lost on me, similar to how I missed the denotation in the statement "from 20 to 15 bar" on the fire pump thread. I am not picking on the person here. Least I am TRYING not to. Just seemed like a statement that needed clarification... "if density has nothing to do with ESFR technology, then how come their orifice is so big? ;-) ESFR's may be tabled in the Standard based on discharge pressure, but truth is, at the relatively high pressures that ESFR's are discharging at (high pressures relative to SS), it is not the pressure that is determining the tenor of the conversation with the fire, (all ESFR's are yelling at the fire), it is the density. ESFR technology is based on too things: early, and lots. the lots gots to do with density. i think the statement that "density has nothing to do with ESFR technology" is defying some law or laws of physics and some conservation equations. fires recognize sprinkler water density. and it very much is a deciding factor as to whether we send Mr. Fire home before the red truck rolls up. scot deal excelsior fire engineering _______________________________________________ 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)
