I think I'd argue with some of the presumptions in Todd's scenaria. Why is a fire contained under a cloud least likely? The heads under the cloud would be the first to be impinged and if you were not at the edge of the of that 100 sqft or larger cloud I can see the jet being cooled as it moves across the cloud. While I'd agree that some under the cloud and some above the cloud is most likely we're still talking less than all the design area above and below. All above is my least vision but I am picturing clouds covering most of the room's footprint. Even if this isn't the case we will have water from above the cloud pouring off the edges of clouds breaking up the fire if it crosses an opening and containing it to a perimeter, probably substantially less than the design area if small clouds and definitely so if large clouds. Picture this (and when this thread is exhausted I'll share an informal interpretation if anyone is interested): Let's say six ducts, each, say, 46" wide, running parallel, with a, say, 1/2" gap between them. Per NFPA do you need to sprinkler under them? And since I'm bouncing around this topic we, myself included, spend a lot of time on this forum speculating, guessing, logocizing (I think that's a new word), etc. We do it for differing reasons, mostly stemming from the rulebook not quite covering every way an architect can figure out how to make our job difficult. So we get stuck with Magic Pixie (I like that one and so will stick with that) interpretations, both techs and engineers. We typically have a solution we want and I'll use Bob as example since he started this line of questioning. He was a hoping for a solution that went a certain way. After Todd's argument of yesterday he resigned himself to that approach but you could read between the lines that there was a tone of defeat. After my argument he changed with a more uplifting tone. Todd and I are jousting over this but neither of us are right or wrong because of the Magic Pixie factor involved. My drivers are from the standpoint of doing this academic thing for a dozen or so years. I'm no longer informed viscerally by the realities of the marketplace although I am quite aware and experienced in that reality. Todd is in the maw daily and has that Damoclean Sword call PE hanging over his head. Others have other demons informing their judgement and in this issue we have only inference to guide us. I have a meeting so I'll spare you all for the moment. And Cecil, if one of us can pull off that stuff I sent you the other day we'll talk Champaign. We'll talk anyway. Maybe August. And why am I on the totally ineffective 1031 Committee and not a 13 committee? This needs top be addressed to our corporate overlords. All hail Caesar Moneybags, Oligarch of Monopoly and the Shattered Economy.
On Tue, Mar 29, 2011 at 6:45 AM, Ronl.Fletcher <[email protected]> wrote: > 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) > -- Ron Greenman Instructor Fire Protection Engineering Technology Bates Technical College 1101 So. Yakima Ave. Tacoma, WA 98405 [email protected] http://www.bates.ctc.edu/fireprotection/ 253.680.7346 253.576.9700 (cell) Member: ASEE, SFPE, ASCET, NFPA, AFSA, NFSA, AFAA, NIBS, WSAFM, WFC They are happy men whose natures sort with their vocations. -Francis Bacon, essayist, philosopher, and statesman (1561-1626) _______________________________________________ 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)
