Chris makes a more than valid point here regarding water supply and manning issues. In fact, the fire service continually debates manning and related issues all the time...Heck despite the fact that I generally agree with his premises... I could easily change the flow rates, number of lines and staffing ratios and we would all be hard pressed to hit a REAL answer.
The truth is that the fire service is a human element service and there are rules of thumb and they tend to stick around.....some even quip that the fire service slogan should be "200 years of tradition unhindered by progress." Sadly this sometimes rings true. Which brings me to the real point of my post....Where did the 500 gpm for the first riser and 250 gpm for each additional riser (max 1000 gpm) come from? Do we really need that much water? Particularly in sprinklered low rise buildings? I can see the need in a high rise where stretching lines from the street is not really possible...but do we really need it in a 3 story apartment building that is fully sprinklered? Feel free to start the debate. That is my intent by making this post. Paul Sincaglia, P.E. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Chris Cahill Sent: Wednesday, April 11, 2007 9:28 AM To: [email protected] Subject: RE: Manual wet standpipes This is theory vs. reality issue. To flow 1000 gpm in a building either the FD needs to have 4-5 2-1/2" lines in operation or about 8-9 1-3/4". Each line takes 3-4 people to staff or one company. So the optimistic case with the rare FD set up with 2-1/2" lines 4 companies on the lines, plus at least 2 interior search and rescue, one outside to rescue FF if need be. Now we need to add all their replacements for when they run out of air and for them to get rest. So conservatively triple the number of working units to keep 4 lines in operation. And if you ever handled 2-1/2" hose under fire condition really 2 companies per line is necessary if you actually try to advance the hose. So IMHO 19 companies plus any logistical support is the minimum to sustain 1000 gpm in a building. There are very, very few places that could do this, even with mutual aid. Then there is another discussion about where exactly do you put 1000 gpm. If the fire is that big you got to start asking what are you doing inside the building. So theory is plan for 1000 gpm, reality is the human element can't or shouldn't pull it off. I'm sure someone will give an example of where it was done but these will be few and far between. I'd limit guesses to FDNY, BFD, Philly, Houston, Dallas, Miami, LA, SFFD, Chicago and at best a few other big cities. Neither Minneapolis nor St. Paul IMHO could do it, maybe working together, maybe. And they are like top 60 sized cities in the US. I'll admit another bias of mine. If the sprinklers don't control it or the first line doesn't get it the FD is just putting on a show for the public. Or at least with regards to the building of origin. For you other FF out there how many times did you give yourselves a high five for a great save only to see the dozers the next day. Chris Cahill, P.E. Fire Protection Engineer Sentry Fire Protection, Inc. 763-658-4483 763-658-4921 fax Email: [EMAIL PROTECTED] Mail: P.O. Box 69 Waverly, MN 55390 Location: 4439 Hwy 12 SW Waverly, MN 55390 -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Greg McGahan Sent: Wednesday, April 11, 2007 7:14 AM To: [email protected] Subject: RE: Manual wet standpipes Along these same lines, why doesn't the code dictate FDC sizes based on system demand? For instance if there is one FDC feeding 3 standpipes I believe that 14 should require a minimum of a 3 way FDC to eliminate confusion and argument. Greg Living Water Fire Protection, LLC 1160 McKenzie Road Cantonment, FL 32533 850-937-1850 Fax: 850-937-1852 _______________________________________________ Sprinklerforum mailing list [email protected] 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 [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
