My answers below. Paul J. Pinigis, P.E. Chief Life Safety Engineer
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Haji, Jaber M Sent: Tuesday, January 09, 2007 12:52 AM To: [email protected] Subject: Sprinkler and fire pump questions Good Morning and Happy New Year! I 'm hoping you are able to assist me in answering some sprinkler/fire pump questions ( I know you have the expertise). The word file is attached. Many thanks in advance and warm regards. Jaber M. Al-Haji [EMAIL PROTECTED] 1) Given that a fire pump is required to serve the sprinkler system in a building and the pump is skid mounted pre-packaged fire pump system designed for the required sprinkler flow. The package will include the fire pump, jockey pump, controllers, backflow preventer and interconnecting piping and valuing. Arrangement and piping is per NFPA 20. The system is assembled and pre-piped at the factory and shipped on a steel frame base. All components are UL/FM approved. Backflow preventer questions. A. Backflow Prevention for Fire Pump. ( ) No backflow valve required ( ) Backflow valve required ( X ) It depends upon the requirements of the water purveyor, whether any chemicals or foam concentrates are added. B. Backflow preventer location in relation to fire pump suction and discharge ( ) On discharge side of pump per NFPA 20 (Preferred arrangement) ( ) On suction side of pump inside building. (Contrary to NFPA 20 but may be required by water utility) ( ) Outside the building in pit or above grade. ( x ) this also depends upon the requirements of the water purveyor. C. Backflow preventer orientation for backflow preventer located on suction side of pump (some jurisdictions have strict requirements about how the backflow preventer is oriented): ( ) Horizontal ( ) Vertical (preferred) ( x ) this depends upon the listing of the device, not all are listed for vertical installation. Note: If a Reduced Pressure Zone valve is required on suction side of pump, is vertical installation acceptable? 2) Fire Pump Accessory Questions: Are any of these accessories typically required? A. Pump Suction Control Valve: This valve senses the suction pressure and throttles down the supply to ensure that the suction pressure does not drop below 20 psi. Target, NFPA and FM prefer not to have this option on fire pumps because it may limit the water available to the sprinkler heads. This is a requirement in some jurisdictions to attempt to protect the city water mains from stress under low pressure. ( ) Not required ( ) Required ( x ) may be required by your water purveyor. B. Low Suction Shut-Off Panel: This panel shuts down the fire pump if the suction pressure drops below 20 psi. Target, NFPA, FM strongly prefer not to have this option on fire pumps for the reason that the fire pump could shut down in a fire situation. This is a requirement in a select few jurisdictions (primarily WI, IL, IN, OH, MI) to protect the city water mains from stress under low pressure. ( ) Not required ( ) Required ( x ) may be required by your water purveyor. C. Emergency power backup required for electrical fire pump. ( ) Not required ( ) Required ( x ) depends upon whether or not you have a "reliable" power supply. Remarks: If emergency power is required, the emergency generator will be sized to handle the fire pump load. Coordinate requirement for generator size and reduced voltage starting requirements. _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum
