April 25, 2016
Clapper in the Fire Department Connection "There are some buildings connected by one underground fire loop and share a fire department connection (FDC) located close to the street for ease of access. The FDCs are not traditional where a welded "Tee" is about 4 ft tall by 4 ft horizontal piping where there are four welded outlets that contain a 2 1/2 in. threaded nipple and a 2 1/2 in. hose adapter. Is an integral clapper a required component for a fire department connection (FDC)?” We have reviewed NFPA 13, 2016 edition as the applicable standard. Our informal interpretation is that clappers or check snoots should have been installed for the inlets. The NFPA 13 standard is silent regarding the clappers inside the FDC. The clapper must be present when there are two or more inlets in the FDC per its listing by UL and FM Global. Clappers swing freely and open to incoming water at the connections and close the opening to unused inlets by water pressure. That way the hose supply does not have to be depressurized to connect additional hoses to the FDC. In addition, the clappers also prevent backflow into hose lines of lower pressures. Hose inlets on fabricated welded pipe or manifold as a FDC are not uncommon. The arrangement doesn't use a listed FDC device and could be problematic during use without the clappers. The manufacturers of inlet connections also make check snoots for individual inlet connections. The check snoot would've been ideal for use as the inlet connections on the FDC for the piping arrangement that you described. A clapper is provided for each individual hose inlet. For a single hose inlet for small diameter risers and residential systems, a clapper would not be required per a UL representative. This makes sense for a single inlet as no additional hoses would be connected. One other residual function of the clapper or check snoot is that when the hoses are disconnected, there is not a flow back of water inside the FDC piping pouring onto the person handling the hose. The NFPA 25 standard also supports the use of clappers for the FDCs and references clappers in two areas. First, Section 13.7.1 indicates that FDCs shall be inspected quarterly to verify the clapper(s) is in place and operating properly. Secondly, Table A.3.3.7 Water-Based Fire Protection System Inspection and Testing Findings says that it is considered an impairment when the FDC's clapper is not operating properly or missing and provides a reference to Section 13.7.1. With that said, clappers would not apply to single inlet FDC connections including the large diameter quick-connect FDC hose connections named Storz. The Storz inlet connections have no clapper provided since that is a single hose connection. Technical Update is prepared by the Technical Services Dept. of the AFSA: Vice President of Engineering and Technical Services Roland Huggins, a PE registered in fire protection engineering; Tom Wellen, a PE registered in fire protection engineering. This is provided with the understanding that the AFSA assumes no liability for this opinion or actions taken on it and they are not to be considered the official position of the NFPA or its technical committees. Copyright 2016, American Fire Sprinkler Assocaiton Ada Dickson Ada Dickson Administrative Assistant Technical Services Dept. PH: (214) 349-5965 ext. 124 Fax: (214) 343-8898 E-mail: [email protected] -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.firesprinkler.org/private.cgi/sprinklernotes-firesprinkler.org/attachments/20160427/e39d48aa/attachment.htm>
