Ord 2001-058 - Laserfiche WebLink

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Sewage lift stations RIP Sewage treatment plants RIP Slaughter houses RIP Steam plants RIP Stock yard RIP Schools - colleges, universities, high schools, intermediate schools, RIP middle schools (elementary schools - individual review) Transportation terminal RIP Uses not listed in this table may require backflow prevention through air gaps or backflow prevention assemblies depending on the nature of the use, the equipment and the plumbing system. These will be determined on an individual basis by the director. (g) Auxiliary water supplies. Where a customer is served by an auxiliary water supply in addition to the city water system, all applicable TNRCC regulations must be followed, and the director will determine the type of back flow prevention assembly to be used. (h) Backflow prevention for fire lines . (1) Backflow prevention is required on all new fireline installations. The type and extent of back flow prevention needed for a particular fire protection system is subject to approval by the director. 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 fireline installations must be Underwriters Laboratory listed. (2) Backflow prevention requirements for firelines: Type of Fireline Device or Assembly Fireline with no chemical additive and no D/C additional water supply Fireline with fire hydrant - no chemical additive DCDA (Standard Drawing DD-40-35 thru DD- and no additional water supply -less than 100' 40-36; vault detail Standard Drawing DD-30- total piping from property line 05) Fire protection system utilizing chemical A/G or RIP additives* Fire protection system with access to an A/G or RIP auxiliary water supply* * *Systems with chemical loops and/or foam injection will require a reduced pressure principle 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 reduced pressure principle 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. C:\TEMP\backflow.doc 10