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Commercial Underground Fire Lines

underground pipe

Plan Submittals And Inspections For Fire Protection Systems And Water Supply

Minimum requirements:

Systems include water storage, fire flow, mains, fire hydrants, valves, meters, check valves, fire pumps, and fire sprinkler connections.

Private systems:

Water storage capacity, main size, pipe class and type, depth of bury hydrant type (Clow 960 or equal), type and size of valves, thrust blocks, location and type of fire department connection to fire sprinkler system.

Public Systems:

That portion of the system that is in the public right of way shall be installed per water purveyors standards.  Fire flow shall be as required by the California Fire Code.  That portion of the system that is installed on private property shall comply with the CFC and NFPA Standards for fire flow, main size, pipe type and class, thrust blocks, hydrant locations and spacing.  Where the public water supply is insufficient to provide the required fire flow on-site storage and pumps may be required.

Fire Pumps:

Fire pumps, where required, shall be installed and tested per NFPA Std. 20. 

Fire Hydrants

Residential Subdivisions on a municipal water system shall have a minimum of one 4.5 inch and two 2.5 inch outlets. The fire hydrant shall be UL Listed.

Commercial Projects may be a minimum of one 4.5 inch and two 2.5 inch outlets for light hazzard buildings. For buildings of storage and manufacturing and not covered by light hazzard shall be a minimum of two 4.5 inch and one 2.5 inch outlet.

Control Valves:

All control valves shall of the indicating type. Valves shall be locked in the open position or equipped with tamper switches.

Required tests and inspections:

underground valve


A visual inspection of the installation shall be conducted prior to backfill. All piping shall be tested at 200 psi for a period of 2 hours. All piping, hydrants, and sprinkler connections shall be flushed to ensure that no debris remains in the system. 

Minimum flush line size is 4 inches, for underground pipe 4 inches and greater. All smaller underground may be flushed by a 2.5 inch connection. Flushing shall be conducted using public main pressure or fire pump pressure. Lack of pressure that will not meet the requirements of NFPA will not pass inspection.

The flush shall include the use of a double bag set up or a diffuser. Unsafe flushing practices will not be allowed. If the safety of the construction site workers and inspection staff is noticed then the inspection will be stopped or may be canceled till safety concerns can be corrected.

 

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