In regard to the first question about to WS or not to WS, note that the building code is:
On Mar 8, 2010, at 9:59 PM, John Drucker wrote: > BETWEEN 4 INCHES AND 12 INCHES (102 MM AND 305 MM) AWAY > FROM THE GLASS AND DESIGNED SO THAT THE ENTIRE SURFACE OF THE GLASS > IS WET > UPON ACTIVATION OF THE SPRINKLER SYSTEM WITHOUT OBSTRUCTION. Almost every window glazing condition uses a storefront type framing system where there is a 2" or so frame between the top of the exposed glass and the rough opening. Since we must follow NFPA 13 installation standards, which includes the obstruction rules, and since we must follow the building code requirement to the letter, there is no way to position an unobstructed sprinkler at 4" to 12" from the glass without the sprinkler deflector at least 2" down from the rough opening. In other words in typical architectural conditions this sprinkler must be fully pendent to be "designed so that the entire surface .. is wet". It could not be semi-recessed nor concealed. So if this sprinkler has to look pretty much like a WS anyway, then it might as well be a WS. At least you will have covered all the bases with an installed sprinkler designed for the application. Furthermore, since you cannot have horizontal mullions and since each vertical mullion blocks the glass wetting, you have the nasty situation where the sprinklers drive the architectural design. The flexibility to go to 8 feet with the WS instead of 6 feet with standard sprinklers goes a long way to smooth out the situation. So again, it might as well be WS when the quantity is manageable. Allan Seidel St. Louis, MO _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
