>From what you've written it sounds as if you are going a different direction >than what the AHJ is requesting. From your e-mail it appears that he is only >requesting sprinklers below the mezzanine, not in-racks.
Now what he is asking for to be installed below the mezzanine is the "Intermediate Style" sprinkler such as the Reliable "F-1" or Viking VK550/560 or similar with the integral steel shield. Some of the things you are going to need before going much further are the temperature of the existing ceiling sprinklers and the design criteria of the existing ceiling sprinklers. Looking at Table 16.2.1.3.2 and Figure 16.2.1.3.2(b), even with in-racks the ceiling system criteria would need to supply somewhere between .24 and .26/2000. I'd be suspicious of a 5.6K design system being designed to that criteria. Applying Fig. 16.2.1.3.4.1, per Table 16.2.1.3.2 at 60% of that (somewhere around .15) the ceiling system may work. So what I'm saying is you need more info. You have two issues. One you need to provide sprinklers below the mezzanine since the floor space is now shielded from the ceiling sprinklers. That's a given. Second you need to examine the need for in-rack sprinklers. Depending on the performance of the ceiling system, how you classify the commodity and what your design criteria will be below the mezzanine, you may or may not need in-racks. As you would imagine, I've only spent a few minutes taking a look at this so there may be other potential approaches that would work. But as time is limited I leave that for you to explore. 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 sam b Sent: Thursday, July 23, 2009 7:38 AM To: [email protected] Subject: In rack sprinklers at celing level Hiii I visited a warehouse (8.6 m height) which is protected by upright sprinklers (K-5.6) . Now the client have added a steel mezzanine structure with racks above and below. Now local Fire authority have asked to *provide sprinklers(in rack type) at the ceiling level of the mezzanine for the below racks.* ** Racks below will be stored with electronic good items in cartons (mainly items for electronic panels). Max storage height will be 4 m. Their are 5 multiple row racks (2.4m wide and 9.3 m length) and 2 single row racks of 1.2 m wide and 9.3 m length). aisle width of 1.2 m between racks. >From NFPA ,I could see only one layer rack sprinklers enough for each >rack and since only 9.3 m length I need only 3 in rack sprinklers per rack. when the sprinklers provided at ceiling Is this the correct way forward?? Can we provide In rack sprinklers at ceiling in these cases? I am not finding it easy to locate the answer. Any help welcome Thaanx in advance Sam _______________________________________________ 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)
