Seems comparable to some "shrink" PVC ceilings used instead of a ceiling grid we saw a few years ago. Your situation seems to be more like a bad "ceiling" rather than an obstruction. For the PVC ceilings we concluded that it was incapable of maintaining it's integrity long enough to be considered a ceiling, so we required two levels of sprinklers, calced for both levels operating simultaneously. Your situation seems quite similar.
Rich Richardson Seattle Fire Department -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Ed Kramer Sent: Monday, October 04, 2010 13:30 To: [email protected] Subject: RE: multiple obstructions that total more than 48" It's an assembly occupancy and the banners are proposed to be over one of the main entrances. They're shown to be approx 28' long and would be anchored at about 26' AFF at one end and 21' AFF at the other end. So dropping the entire banner or one end of the banner via a fusible link to the floor probably isn't a good option. If the banners were 48" or less in width, 18" clear space beneath the deflectors were maintained, and they weren't arraigned side-by-side with other banners, I would be allowed to ignore them (just like HVAC ducts). I anticipate the architect will redesign so each banner is 48" wide and the 18" is maintained. His next question will be "What's the minimum gap I must have between my 48" wide banners? 1 foot? 2' feet? 4' feet?" I'm not aware of any guidance in NFPA 13 or elsewhere, but I'm hoping I'm wrong. Ed Kramer > -----Original Message----- > From: [email protected] [mailto:sprinklerforum- > [email protected]] On Behalf Of [email protected] > Sent: Monday, October 04, 2010 12:28 PM > To: [email protected] > Subject: RE: multiple obstructions that total more than 48" > > What kind of occupancy? If these banners could come loose and fall > would it cause an egress issue for occupants trying to exit the area in > an emergency? > > Essentially it sounds like these banners are creating a sub-level > ceiling below the sprinklers. I believe in one of the previous > discussions it was mentioned about these types of items being suspended > with some type of fusible link so that they could drop out of the way of > the sprinkler discharge in a fire event. > > Other issue is if they would not drop out of the way would they hold > water from a sprinkler to the point where the banner could either dump a > large amount of water on person below or fill to the point it could > create an issue with the structure's ability to support the weight? > > What will 18" below the heads accomplish? > > Suggestion: Put the banners on the wall. > > Craig L. Prahl, CET > Fire Protection Specialist > Mechanical Department > CH2MHILL > Lockwood Greene > 1500 International Drive > Spartanburg, SC 29304-0491 > Direct - 864.599.4102 > Fax - 864.599.8439 > [email protected] > http://www.ch2m.com > > -----Original Message----- > From: [email protected] [mailto:sprinklerforum- > [email protected]] On Behalf Of Ed Kramer > Sent: Monday, October 04, 2010 12:56 PM > To: [email protected] > Subject: multiple obstructions that total more than 48" > > I recall this has been discussed, but not recently. > > > > Is there guidance anywhere as to how much gap needs to be between > obstructions (each individual obstruction being no more than 48" wide) > so > that sprinklers are not needed beneath them? > > > > More specifically, I have a project where the architect would like to > install banners beneath the ceiling and does not want sprinklers beneath > the > banners. I'm fairly confident he's willing to lower the banners so > they're > at least 18" below the sprink deflectors. He's also willing to make > them > narrower (48" max wide). But he would like to place them as close > together > as possible (without needing sprinks below them). > > > > Anybody aware of any guidelines for this? > > > > Ed Kramer > > Littleton, CO > > _______________________________________________ > 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:Sprinklerforum- > [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:Sprinklerforum- > [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) _______________________________________________ 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)
