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  • Public Notice

UL Recommends Inspection of Fire Department Connection (FDC) Hinge Pins (Release 19PN-03)

19PN-03 Fire Connection

March 15, 2019

UL recommends those responsible for conducting acceptance testing and inspecting Fire Department Connections in accordance NFPA 25 (Standard for the Inspection, Testing and Maintenance of Water-Based Fire Protection Systems) verify proper securement of the hinge pin.  Based on reports received by UL, hinge pins that are threaded into the FDC body may become loose or displaced in the field if they are not secured properly. Action should be taken to confirm that hinge pins are properly tightened and secured from movement. The FDC manufacturer should be consulted for guidance on specifications for tightening or other means of securement.

The displacement of the hinge pin from the FDC can cause the clapper (an integral component of an FDC that provides a water seal and allows water flow in only one direction) to become dislodged from its intended location.  If the clapper hinge pin is separated or missing, immediate action shall be taken to retrieve the clapper from the fire protection system piping to prevent blockage of water flow.  If the FDC is damaged, repair or replacement should be considered. 

19PN-03 A

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