Todd,
Most likely the pressure would be about 150psi, reducing for a fire location below the valve or increasing for a fire above the valve. (pressure loss due to height P= 0.434 x h) Here is an excellent paper on the subject: http://www.haifire.com/Resources/publications/RFFireHoseFrictionLoss.pdf As for waiting for water, a properly installed accelerator device will open the DPV quickly and by having the nozzle of a 1-1/2" hose open the air will be displaced quickly by the incoming water or if it's a class three stand pipe, just open the 2-1/2 valve until you have a steady stream of water flowing. Yours truly, Capt. Frank J. Herrick -----Original Message----- From: Todd Williams [mailto:] Sent: Wednesday, November 28, 2012 10:27 AM To: [email protected] Subject: fire service questions 1. When a fire department pumps into an FDC, what pressure would they be typically pumping? 2. Does anyone have any practical experience or knowledge in using an automatic dry standpipe? I would think that could be a little scary standing in front of a fire for 30 seconds with a hose in your hand waiting for the water to come out. Todd G. Williams, PE Fire Protection Design/Consulting Stonington, CT 860.535.2080 www.fpdc.com<http://www.fpdc.com> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://fireball.firesprinkler.org/mailman/private/sprinklerforum/attachments/20121129/708173d5/attachment.html> _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
