On several projects we are finding engineered water supply availability coming from the major chain store's engineers. Recently the engineer uses a city water flow test from Cleveland 16" supply and assumes that the closest elevated water tank is empty and reduces static and residual by 30 ft = 13 psi. That becomes the new flow test for hydraulic calcs. Is that in NFPA?
Even good water supplies become inadequate for some of the bigger box stores with flow demands of 1500-2000 gpm. This is NOT Walmart, Lowes or Home Depot. Is this the new norm? Is this the insurance company requirement? Asking the engineers to back up a statement seems hopeless. "We need 1900 gpm at 50 psi at the riser flange including hose streams." But the hydrants are outside so the sprinkler demand is 1400 at the riser. NO, we need the 1900 at the flange. Comments please. Art Tiroly -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of R Richardson Sent: Tuesday, September 23, 2008 10:44 AM To: [email protected] Subject: RE: Flow Hydrant vs. Test Hydrant And to complicate matters, if the site is an urban location with a well gridded system there is no upstream or downstream, water comes from both directions. And there is really no static condition on a large urban system because some amount of water is always flowing. We had a case where residual pressures were taken at multiple locations all within about 1000 ft. of each other, and the residual pressure readings (not "static") were significantly different depending on which direction you looked (north to south, not downstream/upstream), because the source was much stronger in the south relative to the north. Night time to daytime has also been a huge issue here (water utility does not like testing during the day here because they get many complaints about "turbid" water when tested during the day). Maybe your location is a much simpler system. Rich Richardson Seattle Fire Department >>> "Brian Harris" <[EMAIL PROTECTED]> 09/23/2008 07:29 >>> I agree with flowing the hydrant closets to the tap, but how do you tell which way is upstream or downstream? This particular site utility drawing limited at best, it shouldn't make that big of a difference should it? Brian Harris FDFP INC. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Bill Minkel Sent: Tuesday, September 23, 2008 10:19 AM To: [email protected] Subject: RE: Flow Hydrant vs. Test Hydrant I would flow the hydrant closest to where the run-in to the building will be, in general, and put the residual gage upstream of that. Bill Minkel, Sprinkler DesignerMember NFPA Dallas, TX -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Brian Harris Sent: Tuesday, September 23, 2008 9:13 AM To: [email protected] Subject: Flow Hydrant vs. Test Hydrant O.K., can someone please help a dummy out (that would be me)? When looking at a Civil Site Utility plan what method do you use to determine which hydrant you want to flow and which one you put the gauge on? I've heard a couple different ways, just wanted to get a popular opinion Regards, <http://www.firstdefensefire.com/> E-mail message checked by Spyware Doctor (6.0.0.383) Database version: 5.10760 http://www.pctools.com/en/spyware-doctor-antivirus/ _______________________________________________ Sprinklerforum mailing list http://lists.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) E-mail message checked by Spyware Doctor (6.0.0.383) Database version: 5.10760 http://www.pctools.com/en/spyware-doctor-antivirus/ E-mail message checked by Spyware Doctor (6.0.0.383) Database version: 5.10760 http://www.pctools.com/en/spyware-doctor-antivirus/ _______________________________________________ Sprinklerforum mailing list http://lists.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 http://lists.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 http://lists.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)
