Dan- You could flow more than 12 at the roof in order to flow the required minimum MRA. You could be adding 2 more below obstructions. You could flow more than those 15 if the insurance or other AHJ directs you to.
Only thing more serious than the % impact you mention would be NOT having it when you need it. Those fire videos James includes in his seminars certainly make a memorable example of howcuz ya need all that water, and what happens if ya don't. can you spell free burn? glc -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of danarbel Sent: Wednesday, November 05, 2008 2:40 AM To: [email protected] Subject: RE: ESFR Heads below obstructions Ken, Getting through all the quotes below I still don't see a statement that the 2 head below obstruction are added to the 12 heads required under the high level. In addition, all the clauses you quote say essentially the same thing, that 2 heads should be included in the calc. Namely, why not taking 10 heads in the higher level + 2 heads from the lower level. In my humble mind, adding 2 heads is not logical. Normally the hot gases will bypass the lower level heads. If they are initiated, it means that the gas jet hits the head from below. This is very good since this head initiats just above the source of this hot jet. Maybe in this case one head will do the job. So, again, according to my humble mind, operation of heads under lower obstruction have a positive effect. You will need less higher level heads initiations. I would appreciate any opinions including negative ones to my opinion. Adding 2 heads is 17% more flow, 36% more pressure loss. This is very serious. Dan -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: 05 November, 2008 12:15 AM To: [email protected] Subject: RE: ESFR Heads below obstructions Yeah, 12 above (four sprinks on three branch lines), minimum design area of 960 sq. ft., plus when installed above and below obstructions include discharge for two additional sprinklers for one of the other levels. (NFPA 13, 2002, 12.3.2.3.3 & 12.3.2.3.4) 12+2=14. Yup that's why I got. Did have to take the shoes off to verify that data, so we should be good to go. Craig L. Prahl, CET Fire Protection Specialist Mechanical Department CH2MHILL Lockwood Greene 1500 International Drive PO Box 491, Spartanburg, SC 29304-0491 Direct - 864.599.4102 Fax - 864.599.8439 [EMAIL PROTECTED] http://www.ch2m.com -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Travis Mack, SET Sent: Tuesday, November 04, 2008 5:03 PM To: [email protected] Subject: RE: ESFR Heads below obstructions It must be the election that is frying our brains. I read all of that and see you need 12 at the roof, plus up to 2 below the obstruction for a max of 14 ESFR sprinklers. What say everyone? T-Mack -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of danarbel Sent: Tuesday, November 04, 2008 2:48 PM To: [email protected] Subject: RE: ESFR Heads below obstructions Well, I read all that and it seems that all you need are 12 heads Dan -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: 04 November, 2008 7:28 PM To: [email protected] Subject: ESFR Heads below obstructions Dan, All references here are from the '07 edition of NFPA-13: 14.4.4 Where ESFR sprinklers are installed above and below obstructions, the discharge for up to two sprinklers for one of the levels shall be included with those of the other level in the hydraulic calculations. 15.4.4 Where ESFR sprinklers are installed above and below obstructions, the discharge for up to two sprinklers for one of the levels shall be included with those of the other level in the hydraulic calculations. 16.2.3.5 Where ESFR sprinklers are installed above and below obstructions, the discharge for up to two sprinklers for one of the levels shall be included with those of the other level in the hydraulic calculations 16.3.3.6 Where ESFR sprinklers are installed above and below obstructions, the discharge for up to two sprinklers for one of the levels shall be included with those of the other level in the hydraulic calculations. 17.2.3.4 Where ESFR sprinklers are installed above and below obstructions, the discharge for up to two sprinklers for one of the levels shall be included with those of the other level in the hydraulic calculations. 17.3.3.5 Where ESFR sprinklers are installed above and below obstructions, the discharge for up to two sprinklers for one of the levels shall be included with those of the other level in the hydraulic calculations. 22.4.4.6.4 The requirements of 22.4.4.6.1 to include every sprinkler in the design area to be included in the system discharge shall not apply; where ESFR sprinklers are installed above and below obstructions, the discharge for up to two sprinklers from one of the levels shall be included with those of the other level in the hydraulic calculation. Based on what I read in the ROP just published it doesn't look like any of these have been removed, although it appears that the wording in 22.4.4.6.4 has been moved around a bit, and a new 22.4.4.6.4.1 has been added (See 13-462, Log CP82 in the ROP) Hope that is what you were after. * *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 danarbel wrote: > Question regarding the number of ESFR heads required for hydraulic calc. > > The nominal number is 12. > > There was a requirement to add 2 heads if there are heads installed > below beams or AC ducts. > > If I'm not wrong the addition of 2 heads was abolished. > > Please confirm or correct me, > > Dan Arbel > > > _______________________________________________ > 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) > > No virus found in this incoming message. > Checked by AVG - http://www.avg.com > Version: 8.0.138 / Virus Database: 270.8.6/1765 - Release Date: > 11/3/2008 4:59 PM > > > > _______________________________________________ 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) __________ NOD32 3580 (20081103) Information __________ This message was checked by NOD32 antivirus system. http://www.eset.com _______________________________________________ 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) __________ NOD32 3583 (20081104) Information __________ This message was checked by NOD32 antivirus system. http://www.eset.com _______________________________________________ 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) __________ NOD32 3580 (20081103) Information __________ This message was checked by NOD32 antivirus system. http://www.eset.com _______________________________________________ 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)
