The water for the hose streams does not flow through the sprinkler system so it does not increase the pressure demand at the base of the riser or at the connection to the municipal supply.
That being said, I have fallen back on this explanation before: "This method is the very thoroughly tested industry standard that has proven itself reliable in providing an adequate water supply for decades. It may not 100% accurately describe the behavior of the water in the pipes, but it is not supposed to." Matt Grisé PE*, LEED AP, NICET II Sales Engineer Alliance Fire Protection 130 w 9th Ave. North Kansas City, MO 64116 *Licensed in KS & MO 913.888.0647 ph 913.888.0618 f 913.927.0222 cell www. AFPsprink.com -----Original Message----- From: Sprinklerforum [mailto:[email protected]] On Behalf Of Lamar Vaughn Sent: Tuesday, November 18, 2014 1:18 PM To: Sprinkler Forum Subject: Re: Hose added to calc's. no PSI You have already answered the question by referring to the fire truck as a pump, which it is. If more pressure is needed,they simply pump it. Lamar Vaughn, SET On Tue, Nov 18, 2014 at 2:15 PM, Brian Harris <[email protected]> wrote: > Duane- > I've sent him a copy of our calc's showing exactly what you described > with the flat line, he's still convinced that the added flow (250) > will required more pressure. Not that it's totally accurate I told him > to think of the fire truck as a pump and it was providing the pressure > for the outside hose streams... > > Brian Harris, CET > BVS Systems Inc. > bvssytemsinc.com > > -----Original Message----- > From: Sprinklerforum [mailto: > [email protected]] On Behalf Of Duane > Johnson > Sent: Tuesday, November 18, 2014 2:05 PM > To: [email protected] > Subject: RE: Hose added to calc's. no PSI > > We allow for the fire department to fight the fire while the > sprinklers are activated. So, while the sprinklers are flowing at X > psi @ Y gpm, the fire department will open up a fire hydrant to flow > additional gpm. The pressure they use is less than the sprinkler > requirements. Therefore we need to account for additional gpm, but not > additional psi. Show him a graph with the horizontal line at the top of the > sprinkler demand... > > Duane Johnson, PE > Design Manager > Strickland Fire Protection > 301-474-1136 Office > 301-455-0010 Cell > > > > -----Original Message----- > From: Sprinklerforum [mailto: > [email protected]] On Behalf Of Brian > Harris > Sent: Tuesday, November 18, 2014 1:59 PM > To: [email protected] > Subject: Hose added to calc's. no PSI > > I've been trying to explain to a civil engineer that we (fire > sprinkler) include outside hose allowance into our calc's but only for > the extra gpm, not as far as additional psi goes. I'm sure it's the > way I'm trying to explain it that's not making any sense to him, can > one of you more versed in the English language help me out and put it in > layman's terms for me? > > Brian Harris, CET > BVS Systems Inc. > Sprinkler Division > bvssystemsinc.com<http://bvssystemsinc.com/> > Phone: 704.896.9989 > Fax: 704.896.1935 > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkl > er.org _______________________________________________ > Sprinklerforum mailing list > [email protected] > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkl > er.org _______________________________________________ > Sprinklerforum mailing list > [email protected] > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkl > er.org > _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
