Number of Fire Pumps

[mamoizkhan1967]

Is it mandatory to have a primary and a standby Fire Pump? One of our sub contractor has given me a P&ID showing a Diesel operated Vertical Turbine pump as main Fire pump and a small pump (Jockey Pump). Can i ask him to add one more Electric operated Pump of same specs as the Diesel pump. Would Code NFPA 20 makes it mandatory to have a Primary Electric Motor operated pump and a Secondary Diesel operated Standby Pump, Plus a Pressure Maintaining Pump (Jockey Pump). I have little knowledge in this field , kindly help.

 

[SprinklerDesigner2]

NFPA 20 does not require two fire pumps but if electric it must have a reliable source of power.

Whenever I have seen two pumps, one diesel one electric, it has always been on a high value property on a very large complex but the decision to have two pumps is always made by the insurance carrier and not the standard.

 

[LCREP]

Is it mandatory to have a primary and a standby Fire Pump? One of our sub contractor has given me a P&ID showing a Diesel operated Vertical Turbine pump as main Fire pump and a small pump (Jockey Pump).

Yes most times this would be the set up, the small electric pump is to prevent the large pump coming on for small leakes in the system such as an underground leak.



Can i ask him to add one more Electric operated Pump of same specs as the Diesel pump.

Sure you can ask him, not required by NFPA 20 unless the power supply is not reliable.

As sprinkler design 2 stated check with the insurance carrier they may mandate a second pump based on $$$ at risk and occupancy. Also depending on what code the building is being designed to it may require a back up such as a high rise building.

 

[mamoizkhan1967]

Thanks.
The specifications of pumps show the diesel power pump at 500 USGPM at 11 bar. While the small pump is 20 USGPM at 8 bar. The fire ring consists of pillar type Hydrant (39 nos.) PN16 with 4 inch dia fanged inlet and double delivery outlet, brass instantaneous female coupling 2 1/2 inch dia hose pipe. Main ring is of 160 mm HDPE 100.
Does the pressure and flow specs normal for such type of system. does the pipe size correct.