And that's what happens when AHJs have a better idea that serves no function other than to complicate things. They're already demanding cushions while expecting every fire to be the unlikely one tat actually does occur in the design area with all heads flowing even though statistics demonstrate, and they tout those numbers themselves, MOST, not all but most, fires are controlled with two to three heads flowing. And I'll suspect that most of those involve simple NFPA systems, both new and old, but the focus is always on the one that got away as typical. Couple of things. NFP was originally a consortium of insurers. That suggests that the losses were more of a business concern than societal, and although the society as a whole has evolved it's own show pony, originally this was an insurance, i.e., money issue. Then if you look at FM requirements, a little more stringent and therefore a little more costly than NFPA, they're still doable and usually have a good rationale behind them, rather than some of the nonsense I've heard from AHJs (and some crazy interpretation because of wording in NFPA--like why doesn't 25 just say "exercise" and define an orifice size vis-a-vis the incoming line just like with main drains?), and these are for their HPR properties. Americans demand a risk free life and so live in constant fear and are willing to through copious quantities of money at any snake oil salesman that will tell them they'll live forever with no fear of ever being in a state of being other than happiness. The only people free from risk are the dead.
On Sat, Jul 27, 2013 at 7:43 AM, Tom Duross <[email protected]> wrote: > I think an augmented hydraulic nameplate would work if done when > commissioned just to try and establish some benchmark. Springs weaken in > time and corrosion enters into the mix so Pin vs. Pout at Q could change. > Also when BFP's are just line sized (like PRV's) as opposed to design rate > at velocity listings, losses cam be different than published. I've had > PE's > require 7.5 FPS flows right out of the listing charts and we couldn't meet > them with city pressure (2X design). What then, duals? It's a quagmire. > TD > > > Why cant we just use the hydraulic data plate for the demand needed and add > a line for maximum pressure loss allowed through backflow and leave it at > that? Then if the backflow is replaced there is a number to work to and you > know how much flow is needed if it is measured. > > > > On Fri, Jul 26, 2013 at 5:34 PM, John Denhardt < > [email protected] > > wrote: > > > Sounds like a good opportunity for a public input. > > > > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org > -- Ron Greenman Instructor Fire Protection Engineering Technology Bates Technical College 1101 So. Yakima Ave. Tacoma, WA 98405 [email protected] http://www.bates.ctc.edu/fireprotection/ 253.680.7346 253.576.9700 (cell) Member: ASEE, SFPE, ASCET, NFPA, AFSA, NFSA, AFAA, NIBS, WSAFM, WFC, WFSC They are happy men whose natures sort with their vocations. -Francis Bacon, essayist, philosopher, and statesman (1561-1626) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
