My recollection of the 7 psi min ehp was to make sure the cap was removed and an acceptable pattern developed.
Thought it took 5 psi to clear the waterway so 7 became the min, maybe for pattern, maybe buffer. Mark, that's a Min ehp. With today's hi perf heads we often need lots more, determined also as you illustrated. Glc Sent from my iPhone On May 21, 2013, at 9:42 AM, "Brad Casterline" <bcasterl...@fsc-inc.com> wrote: > For example foam/water deluge .16/entire area, heads 9x9=81, times .16=12.96 > gpm/head, throwing 4'-6" each way. The requirement to balance the flows > within 15% of each other is physical (we want a fairly uniform blanket on > the floor), but the 7 psi min is not physical, unless 5.48 psi will not > throw 4'-6". Thanks Mark. > > -----Original Message----- > From: mphe...@aerofire.com [mailto:mphe...@aerofire.com] > Sent: Tuesday, May 21, 2013 8:31 AM > To: sprinklerforum@lists.firesprinkler.org > Subject: Re: calc procedure logic > > Wouldn't it depend on the application rate, area of protection and orifice > size? > Mark at Aero > > ----- Original Message ----- > From: Brad Casterline [mailto:bcasterl...@fsc-inc.com] > Sent: Tuesday, May 21, 2013 01:03 PM > To: sprinklerforum@lists.firesprinkler.org > <sprinklerforum@lists.firesprinkler.org> > Subject: calc procedure logic > > Would the 7 psi minimum operating pressure from NFPA 13 Calculation > Procedure apply to open head deluge, since the operating parts have already > been ejected clear of the frame and deflector by a ball-peen hammer? > > > > Brad Casterline, NICET IV > > Fire Protection Division > > > > FSC, Inc. > > P: 913-722-3473 > > bcasterl...@fsc-inc.com > > www.fsc-inc.com > > > > Engineering Solutions for the Built Environment > > > > _______________________________________________ > Sprinklerforum mailing list > Sprinklerforum@lists.firesprinkler.org > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org > > > _______________________________________________ > Sprinklerforum mailing list > Sprinklerforum@lists.firesprinkler.org > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org > > _______________________________________________ > Sprinklerforum mailing list > Sprinklerforum@lists.firesprinkler.org > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list Sprinklerforum@lists.firesprinkler.org http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
