7.9 Water Supply for Fire Protection
Adequacy of Water Supply. The designer shall assess adequacy of the existing water supply. The designer shall perform water supply flow testing of fire hydrants and/or fire pumps. If data less than one year old is available from the local jurisdiction, the designer shall verify the locations involved as well as the quality and accuracy of the data.
Capacity and Duration. The required fire flows and pressures for buildings shall comply with NFPA 13 and the National Model Building Code.
Fire Pump Design. When a fire pump is necessary to supplement fire flow and pressure, size it to comply with NFPA 13, 14, and 20. For emergency power requirements see Chapter 6.
Special Requirements. The requirements below supersede the fire pump requirements of NFPA 13, 14, and 20:
- The fire pump shall be sized only for the sprinkler system requirements unless the local responding fire department cannot provide the necessary flow and pressure for manual fire fighting operations (i.e., hose stations).
- The fire pump shall be electric motor driven, horizontal split case centrifugal type, unless this is not feasible.
Fire Pump Installation
The fire pump shall be installed in accordance with the requirements of NFPA 20.
Fire Pump Operations. A fire pump shall start automatically at 69 kPa (10 psi) below jockey pump start pressure. Fire pumps shall be designed for manual or automatic shut down. Manual shut down of the fire pump will ensure that the pump does not shut down prematurely before controlling the fire.
Fire Pump Controller. The power transfer switch and the fire pump controller shall be factory assembled and packaged as a single unit. Separate transfer switches are not permitted. The fire pump controller shall be monitored by the fire alarm system.
Jockey Pump. A jockey pump shall be utilized where it is desirable to maintain a uniform or relatively high pressure on the fire protection system. A jockey pump shall be sized to make up the allowable leakage rate within 10 minutes or 1 gpm, whichever is larger.