Chris is correct. Reliable model A flush sprinklers were found at Argonne National Labs East in June 1998 that did not operate at high pressures, some in the 100 psig range and higher. They were tested because of some concern with visible corrosion on the outside. We had some of this model at our facility and, at the request of the DOE, supplied the CPSC with 28 heads. They tested them in 1999 and had 12 of 19 failed to open at 7 psi. The pressure was increased on the 12 until they did actuate but I never got a final report showing at what pressures they did actuate, even after requesting it.
After the 1997 reports of Omegas not operating during fires but before the October 1998 recall of the Omegas, we were remodeling our lobby that had Star Model G concealed heads. These have o-rings so we decided to test them here with our maintenance people. These were 1972 heads replaced in 1998. We tested 10 of the 32 sprinklers removed. Of the 10, 2 operated at 7 psi. We increased the pressure on the remaining 8 and they all operated from 13 psig to 28 psig. So it wasn't just the Omegas that were a problem. We have done no other testing of o-ring sprinklers since then. 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 09/17/2009 03:46:42 PM: > [image removed] > > RE: Chewable topic.....Omegas > > Chris Cahill > > to: > > sprinklerforum > > 09/17/2009 03:46 PM > > Sent by: > > [email protected] > > Please respond to sprinklerforum > > This all went down a little more than 10 years ago. Wonder if there has > been any follow up testing to see if the problem has gotten worse regarding > the failure rates at the various pressures? Wonder if there is an increased > probability of actual failure in actual systems under real conditions? > > I believe in the beginning many thought it is a problem but discounted > because as the pressure rose the failure dropped quick. And it was real > small at the pressure normally on systems and only 1 or 2 heads usually > operate. Like our AHJ Dave pointed out if you are at 7 psi I think you have > a much bigger problem. But if there are failures at larger rates at say 50 > psi maybe that is now really the problem that wasn't there years ago. > > Chris Cahill, P.E. > Fire Protection Engineer > Sentry Fire Protection, Inc. > > 763-658-4483 > 763-658-4921 fax > > Email: [email protected] > > Mail: P.O. Box 69 > Waverly, MN 55390 > > Location: 4439 Hwy 12 SW > Waverly, MN 55390 > _______________________________________________ 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)
