Ord 2011-006 - Laserfiche WebLink

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complete replacement of the device to meet the ordinance requirements • and construction standards. Pressure losses across backflow prevention assemblies must be accommodated in the design or redesign of a fire protection system. This factor is particularly important when redesigning existing fire protection systems. All backflow prevention assemblies for fire line installations must be Underwriters Laboratory listed. (2) Backflow prevention requirements for firelines: Type of Fire line I Device or Assembly Fire line with no chemical additive and no D3 G DCDA additional water supply Fire line with fire hydrant - no chemical DCDA (Standard Drawing DD -40 -35 thru additive and no additional water supply — DD- 40 -36• vault detail standard drawing less than 100' total piping from pr-epeiy DD- 30 -05) l*e the fire line tap valve Fire line utilizing a pressure pump system A/G or RPDA Fire protection system utilizing chemical I A/G or RPDA additives* Fire protection system with access to an auxiliary water supply ** A/G or RPDA * Systems with chemical loops and/or foam injection will require a Rreduced !!pressure Pprinciple • Detector backflow prevention assembly at the loop or foam injection point; however, an expansion chamber or relief valve will have to be installed to compensate for thermal expansion in accordance with the fire code. The installation of Rr-educed Ppressure !!principle Detector assemblies for containment backflow prevention on firelines should be avoided and installed only in situations where chemical injection occurs prior to any taps or tees. ** Existing chemical loops and systems with access to an auxiliary water supply must be retrofitted with an approved assembly. (3) Tri-water system or circulated closed -loop systems, such as a combination fire line, heating and cooling system, are prohibited. (4) Full -flow testing or assembly tear -down requirements for firelines. Backflow prevention assemblies installed on firelines must either be full - flow tested at least once each five years, or must be completely torn down and rebuilt at least once each five years if full -flow testing cannot be accomplished. The assembly must be cleaned and all rubber parts replaced when deemed necessary by the certified tester or the assembly manufacturer. Assemblies must be tagged by the tester to indicate the tear - down date. If within a five year period, an assembly is torn-down, a new five year tear -down period will begin at that time. If a backflow prevention assembly is found to be malfunctioning in an annual testing process, the assembly must be completely torn-down and rebuilt at that • 14