Ord 2001-058 - Laserfiche WebLink

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(b) Criteria for selection of backflow prevention assemblies. The selection of an appropriate backflow prevention assembly depends upon the degree of hazard involved and will be based on the following criteria: (1) Whether or not the assembly could ever be subject to backpressure due to the customer's internal pumping pressures or elevation differentials. (2) The nature of contaminating material under the most critical circumstances. (3) The extent to which additions may be made to the plumbing system at a later date which would affect the initial selection of the assembly. (4) The frequency with which a water supply could be exposed to a hazardous condition. (5) The degree of protection of the water supply as provided by the local plumbing code as enforced by the building inspections division. (c) Decisions on selection of backflow prevention assembly. The director, acting either personally or through a representative, will have the final approval authority over the type of backflow prevention assembly to be used in each individual case. The director may, in making this decision, obtain the advice and recommendation of the cross connection control committee. (d) All types of establishments listed below must provide for the containment of contamination within their premises, either by an air gap separation between the meter and the first tap or tee, or by having each of the internal plumbing facilities properly air gapped. If the containment air gap separation is impractical, and reliance is placed instead on individual internal air gaps or vacuum breakers in a customer's system, the director may require additional protection in the form of either an RIP assembly, for customers handling hazardous contaminants, or a D/C assembly, for customers handling pollutants. (e) In some instances, the director may require a customer to use total containment backflow prevention to allow the backflow prevention assembly to be installed on an internal branch line. An example of this would be for a combination fire and domestic water service from the city water supply. The backflow prevention for the domestic use would be installed immediately after the fireline tee. In such a case, the fire line must be provided with its own separate backflow prevention. (f) Type of device or assembly required. A/G RIP D/C DCDA PTVB AVB - Air Gap Separation - Reduced Pressure Backflow Prevention Assembly - Double Check Valve Assembly - Double Check Detector Assembly - Pressure Type Vacuum Breaker - Atmospheric Vacuum Breaker Type of Use Device or Assembly Animal feedlots RIP Apartments and condominiums - 4 stories or more RIP Auxiliary Water Supply RIP Breweries RIP Building - 4 stories or more RIP C:\ TEMP\backflow .doc 8