Mark, The UFC standard for wet-pipe sprinkler systems, 21-12-12.00-20, has one option to select as the 12 psi loss for backflows. The other option to choose is the actual loss of the device chosen. It is the designer's option s to which one to pick. The spec writer of the project you were on chose the former for some reason.
John Hoffman P.E. | Fire Protection Engineer | Facility Engineering Services, KCP, LLC - Burns & McDonnell Engineering | National Nuclear Security Administration's Kansas City Plant | Operated by Honeywell FM&T | 2000 E. 95th St | Kansas City, MO 64131 | ph 816-997-7213 [email protected] wrote on 09/24/2009 09:11:49 AM: > [image removed] > > RE: Inadequte Water > > Mark Sornsin > > to: > > '[email protected]' > > 09/24/2009 09:15 AM > > Sent by: > > [email protected] > > Please respond to sprinklerforum > > Steve: > > Which UFL standard is requiring the 12 psi drop across the backflow? > This is the second time I've heard of this but have not yet had to > deal with it (I don't know why not). > > I would LOVE to have a sit-down with the 'powers that be' > responsible for the UFC standards. E.g. where do they get the 3,000 > sq.ft design area crap? They say it's common HPR requirements in > the civilian world - except I worked for FM and we NEVER required 3, > 000 sq.ft. design areas for light or ordinary hazard-equivalent > occupancies. Maybe they just want to cover themselves in case a > combustible concealed space appears... > > Mark A. Sornsin, PE > Fire Protection Engineer > Ulteig Engineers, Inc. > 3350 38th Avenue S. > Fargo, ND 58104-7079 > > Direct: 701. 280.8591 > Fax: 701.280.8739 > Cell: 701.371.5759 > > [email protected] > www.ulteig.com > > Confidentiality Notice > This message may contain privileged and confidential information. If > you think, for any reason, this message may have been addressed to > you in error, you must not disseminate copy or take any action in > reliance on it, and we would ask you to notify me immediately by > return email to [email protected]. > > > > -----Original Message----- > From: [email protected] [ > mailto:[email protected]] On Behalf Of Steve Kowkabany > Sent: Thursday, September 24, 2009 7:18 AM > To: [email protected] > Subject: RE: Inadequte Water > > I have the single most frustrating water issue I have ever had going on > right now Greg. I am working on this small commercial entrance facility at > a military base in Georgia. We are only sprinklering a small 3,800 sqft > cargo transfer building and getting the water from the local utility rather > than the base. > > We designed based on modeling data that was the only thing available at > design (there was no water within a mile then) and had no problem making the > small light hazard wet system work. > > Last week the underground was finally finished and we had our main run up to > the building and some nearby hydrants to test, so we tested them - 55/25 at > 750 gpm. Bad water but still enough to make an little light hazard wet > system work right? > > Not once you take a 3,000 sqft design area, a 500 gpm hose allowance due to > the presence of 300 sqft of OH1 rooms, and a mandatory 12 psi pressure > across the BFP regardless of the fact that it is actually a double-check - > all mandatory per UFC codes. After all that, you need 850 gpm at 40 psi to > make this system work and we are looking at a pump and a tank! > > It's a very frustrating situation, so feel free to tell your AHJ he is not > alone. > > > Steve Kowkabany, P.E. > Fire Protection Engineer > Neptune Fire Protection Engineering LLC > 616 Davis Street > Neptune Beach, FL 32266 > 904-652-4200 Phone > 904-212-0868 Fax > > _______________________________________________ > 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)
