Just check/consider spacing of both complements and go on from there. We do a lot of schools and colleges; one of the most common upgrades to high school and community college campuses over the past 2-3 years has been performing arts buildings. These are usually Type II shells with suspended acoustical panels and a common dimensional increment for these is 20', so if the water pressure is adequate we use EC on the clouds. Sometimes the roof structure doesn't favor EC and it's not uncommon for us to calc' both complements, just to be sure that we've got the more demanding one.
Steve Leyton -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Bob Knight Sent: Tuesday, March 29, 2011 7:40 AM To: [email protected] Subject: RE: Cloud Calculations So, now I'm really baffled. If I follow this whole thread it seems that the consensus would be one level calc'ed only verifying which level has the greatest demand. In my case the sprinklers at the ceiling will be the greatest demand simply due to number and configuration of sprinklers. The clouds in this situation are running both perpendicular and parallel to the branch lines. Some of the clouds are rectangular and up to 12' wide. Other clouds are circular and have up to a 20' diameter. In all the clouds account for about 40% of the space. All the clouds have sprinklers beneath them. Thanks, Bob K -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Ronl.Fletcher Sent: Tuesday, March 29, 2011 7:45 AM To: [email protected] Subject: RE: Cloud Calculations Cecil, Just out to curiosity do any of the models have the clouds hanging at an angle, not parallel to the floor? Modeling and fire testing sounds like a daunting task. Congrats on the grads. Ron Fletcher Aero Automatic Phoenix, AZ -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Sprinkler Academy - C Bilbo Sent: Tuesday, March 29, 2011 6:17 AM To: FORUM Subject: RE: Cloud Calculations I am not sure where you guys have landed in this discussion, but wanted to chime in with the latest work being done by the NFPA 13 Committee. And more specifically, the work being done by the "Ceiling Cloud Task Group". We have begun the tough process of introducing changes to the standard that will inlcude rules for ceiling clouds. I gave a presentation to the Committee of our task group's work at the ROP meeting in February. The task group includes the Chair, David Fuller from FM Global, and Steve Scandaliato, Mike Meehan and others. (Please, if you don't know who these people are, take a miute to look them up. It is awesome to know these folks!) As it currently stands, ceiling clouds are obstructions and require sprinklers beneath (resulting in protection above and below). The calculations are only required to include one level of the sprinklers. Both are NOT requiredto be calculated together. No addtional sprinklers from the lower elevation are required to be included in the remote area at the deck. And vice versa. However, you would need to calculate both levels to determine which is the most demanding area. We are asking the Research Foundation (NPRF) to sponsor testing of the scenarios that Tom Wellen has modeled. All of the Task Group's work starts with Tom's models. We have yet to come to any conclusions for the new rules. But we will likely have separate guidance in the 2013 edition for cloud ceilings so that you will not always have to have sprinklers required above and below and how one might have to calculate these scenarios. (the Academy students got to draw some of the examples that we hope make it into the standard...) And by the way..... the Academy ROCKS!!! We are graduating our first students next month. Four folks will be getting their Associate's Degree in Sprinkler System Technology from Parkland College!! We are going to have one serious party. And you are all invited to come! (Now, if I can just get Ron Greenman to move to Champaign...) It should be recognized that the above is my opinion as a member of the NFPA, and has not been processed as a formal interpretation in accordance with the NFPA Regulations Governing Committee Projects and should therefore not be considered, nor relied upon, as the official position of the the NFPA, nor any of their technical committees. Sincerely, Cecil Bilbo Academy of Fire Sprinkler Technology Champaign, IL 217.607.0325 www.sprinkleracademy.com [email protected] OUR STUDENTS SAVE LIVES!! _______________________________________________ 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)
