The hydraulic calculation will likely go to the effective point of the flow test (in the underground). If you do not adjust for elevation then the calculation is incorrect.
Paul J. Pinigis, P.E. Chief Life Safety Engineer -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of art Sent: Friday, December 14, 2007 12:31 PM To: sprinklerforum@firesprinkler.org Subject: RE: Flow test effective point. What good is pressure 5' below grade. Don't you expect pressures to be at grade or at finished floor? Adjust from gage to finished floor elevation. Does your program expect to see pressures 5' below grade? -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Paul Pinigis Sent: Friday, December 14, 2007 12:16 PM To: sprinklerforum@firesprinkler.org Subject: RE: Flow test effective point. Yes, you must correct for elevation. Paul J. Pinigis, P.E. Chief Life Safety Engineer -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Todd Williams - FPDC Sent: Thursday, December 13, 2007 5:52 PM To: sprinklerforum@firesprinkler.org Subject: Flow test effective point. I thought I understood this, but maybe not. When determining the effective point for a hydrant flow test, I was told that it is at the junction of the flowing and non-flowing water. (for the purposes of this discussion, let's assume that we are talking about a single main, fed from both directions, with hydrants on branches off the main. Pressures are read at one hydrant and another single hydrant is flowed) If this is the case, then the effective point of of the flow test would be at the junction of the main and the branch to the hydrant where the pressures are read. However, this junction occurs underground. If we assume that the gauge on the hydrant is 1'-6" off the ground and the main is 5 ft underground, this would mean that the pressures are read 6.5 ft above the effective point. The pressures at the effective point would be 2.8 psi greater than those read at the hydrant. Is or should a correction be included? This makes a difference on programs such as Autosprink where you draw a 3D model of the underground system and insert a supply at the effective point. Todd G. Williams, PE Fire Protection Design/Consulting Stonington, Connecticut www.fpdc.com 860.535.2080 _______________________________________________ Sprinklerforum mailing list Sprinklerforum@firesprinkler.org http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list Sprinklerforum@firesprinkler.org http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list Sprinklerforum@firesprinkler.org http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list Sprinklerforum@firesprinkler.org http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)