Do what Mike said but pick up the 12th sprinkler off the 4th line. I would imagine the intent of NFPA 13 was to calculated 4 sprinklers on a line as your worst case scenario to prove the line size. Then pickup 12 sprinklers total to get an appropriate total flow. So the standard reference 3 lines to do this as that is the common scenario.
Applying this assumption to your scenario, your 1st two lines have at least 4 sprinklers per line so those are easy enough. Your 3rd line only has 3 sprinklers so pickup all 3 and then pick up the 4th sprinkler on the 4th line. You now have 12 total sprinklers flowing, and the last 4 of these sprinklers are going to overflow more than they normally would if they were on a single line (assuming tree/end fed system). So this should be a more conservative design than what NFPA 13 requires. But you also aren't forcing yourself to go ultra conservative by calculating 5 or 6 sprinklers on a single line which I do not believe was NFPA 13's intent. Thanks, Sean VG From: Sprinklerforum [mailto:[email protected]] On Behalf Of Brian Harris Sent: Tuesday, July 9, 2019 7:44 AM To: [email protected] Subject: [EXTERNAL] RE: ESFR Calc's Mike- The lines on the other side of the wall only have (3) heads per line. Brian Harris, CET BVS Systems Inc. bvssytemsinc.com<https://urldefense.proofpoint.com/v2/url?u=http-3A__bvssystemsinc.com_&d=DwMFAg&c=wn3mZQLIuInh2ClcJ0_DIA&r=XSIweKhAHHhyB-d63TCLaTQ55VHpbhIhFOxEPFjbNpg&m=AWdzKMSnfZTO1yzpl1Dd37Lrr1TeI1Fqx3BWjEHd-Zg&s=QGuUWxAksuh7c7L6oHoglZLzKjOOXn6OYIs8o4Fgsv4&e=> From: Sprinklerforum <[email protected]<mailto:[email protected]>> On Behalf Of Mike Hairfield Sent: Tuesday, July 09, 2019 10:36 AM To: [email protected]<mailto:[email protected]> Subject: Re: ESFR Calc's Why don't you use 2 lines on one side of the wall and 1 line on the other side of the wall thus 3 lines with 4 heads? Mike ________________________________ From: Sprinklerforum <[email protected]<mailto:[email protected]>> on behalf of Brian Harris <[email protected]<mailto:[email protected]>> Sent: Tuesday, July 9, 2019 10:29 AM To: [email protected]<mailto:[email protected]> Subject: ESFR Calc's I have an ESFR system that I do not have (3) rows of (4) heads to calc. Due to compartment wall layouts I have (2) rows of (6) heads and (6) rows of (3) heads. What is the best way to grab (12) heads? Brian Harris, CET BVS Systems Inc. Design Manager bvssystemsinc.com<https://urldefense.proofpoint.com/v2/url?u=http-3A__bvssystemsinc.com_&d=DwMFAg&c=wn3mZQLIuInh2ClcJ0_DIA&r=XSIweKhAHHhyB-d63TCLaTQ55VHpbhIhFOxEPFjbNpg&m=AWdzKMSnfZTO1yzpl1Dd37Lrr1TeI1Fqx3BWjEHd-Zg&s=QGuUWxAksuh7c7L6oHoglZLzKjOOXn6OYIs8o4Fgsv4&e=> Phone: 704.896.9989 Fax: 704.896.1935
_______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
