NFPA #13 says "systems are subject to freezing and temperatures cannot reliably be maintained at or above 40F". So if the temp goes below 40F but the pipe isn't subject to freezing freeze protection is not required. We have installed many wet systems in 34F-36F coolers. I believe the 2" pipe requirement is an old ISO precaution and is written into some jurisdictions amendments here in AZ but I have never seen it in any national code or standard.
Ron Fletcher Aero Automatic Phoenix, AZ -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Seidl Jamie D. Sent: Tuesday, June 19, 2012 5:30 AM To: [email protected] Subject: RE: California question about freezing Chris, while I am sure you know about the requirement for a sprinkler system to be maintained at 40F. With the temp noted below of 33F, this requirement probably cannot be met. There are several system options like heat tracing, dry system or anti-freeze systems. If these are not an option, you could also calculate the heat loss, sign and seal and call it a day if you are comfortable with it. We've taken this approach with some customers that were opposed to the maintenance of dry systems and anti-freeze systems etc... pay an engineer to calculate the heat loss, sign seal and submit it to the EOR. -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Chris Born Sent: Tuesday, June 19, 2012 8:12 AM To: [email protected] Subject: California question about freezing We are working on a project at Camp Pendleton, and a question has come up about running some piping exposed. We have a loading dock and originally indicated dry sidewall sprinklers to protect this area. However, due to some coordination issues with a soffit and structural steel, the contractor has proposed running a 2" branch line exposed with sidewall heads straight off of the branch line. I know that it is very common for large piping such as risers, backflow preventers, etc., to be run exposed in this area. However, I'm not as comfortable with a branch line. We've researched the Air Force Climactic Center data and that shows a 99.6% dry bulb temperature of 33F, which would suggest there would be very little to no chance of this line freezing. In the opinion of some of the esteemed West Coast members of this forum, should I be concerned about freezing? Christopher Born, P.E. Director, Fire Protection Engineering Clark Nexsen, P.E. Norfolk, VA Sent from my iPad _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
