Tommy (Yo, dude!), The Pump IS the water supply. In order to drain the system, the Main Drain needs to be on the system side of the pump. And in order to test the water supply to the system (ie: city water + pump. dammit), you gotta flow the water from the city supply through the pump and to the system. This is even more critical when you are supplying multiple standpipes AND sprinklers. NFPA 25 requires an analysis of the city water supply at 5 years. Tom, the beauty of what you do is that you ALWAYS think about the best interest of the owner. And you should rock on in giving the owner the cadillac! But that is not what the NFPA standards are all about (even if we want to encourage such a thing). NFPA has to draw a line at what the minimum acceptable safety standard should be. The minimum (and it is quite acceptable) is to install a drain (call it main...and each floor would end up having one, right?) and use it to determine whether the ENTIRE water supply is adequate. There ya go.
It should be recognized that the above is my opinion as a member of the NFPA, (you know... 3,4,13,14,25,72,88A & stuff) and has not been processed as a formal interpretation in accordance with the NFPA Regulations Governing Committee Projects and should therefore not be considered, nor relied upon, as the official position of the the NFPA, nor any of their technical committees. Sincerely, Cecil Bilbo Academy of Fire Sprinkler Technology Champaign, IL 217.607.0325 www.sprinkleracademy.com [email protected] OUR STUDENTS SAVE LIVES!! > From: [email protected] > To: [email protected] > Subject: Fire Pump Room Main Drain > Date: Thu, 12 Dec 2013 15:49:56 -0500 > > I'm looking for opinions on this. > > A new building I just took over ITM on has a fire pump feeding combination > standpipes, fully sprinklered high-rise circa 1974. > Existing 2" main drain is toast, handle broken, stem all chewed up from > wrenching. > I proposed we change it, use a 300# ball valve, galvy pipe; do it right. > BUT, it's on the system riser off the pump discharge and I say wrong > location. > Even the standard still says do a main drain test when you have a fire pump > (imho silly), so I do. > A main drain test is to verify supply condition. I say with it where it is, > we either have to drop the building to street pressure OR do a main drain > with the pump running. In a case like this I always do the latter but I see > others dropping the building and I think it's unnecessary and an impairment. > The problem I have with doing 150-200# main drain tests is they do dump a > ton of water, even with a fire hose off the 2" el and a hose monster. > I feel it's overkill and unnecessary on top of a waste of time but whatever. > My issue (finally) is where to properly place a main drain when you have a > pump. I say on the street side bypass supply, just flow supply pressure and > be done with it. Facilities guy says others dumped building and just do > that. > Sprinklers are tested with the pump running, last few companies shut it off > and went on jockey, that's why they're gone. > Looking for opinions and even second opinions (ok you're ugly too). > What's the proper location? > > TD > > _______________________________________________ > 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
