§ 51.72 TYPE OF PROTECTIVE ASSEMBLY.
   The type of protective assembly required shall depend upon the degree of hazard which exists as follows:
   (A)   In the case of any premises where there is an auxiliary water supply, the public water system shall be protected by an approved air gap separation or an approved reduced pressure principle backflow prevention assembly;
   (B)   In the case of any premises where there is water or a substance that would be objectionable but not hazardous to health, if introduced into the public water system, the public water system shall be protected by an approved double check valve assembly;
   (C)   In the case of any premises where there is any material dangerous to health such as to create an actual or potential hazard to the public water system, the public water system shall be protected by an approved air-gap separation or an approved reduced pressure principle backflow prevention assembly. Examples of premises where these conditions will exist include, but are not limited to sewage treatment plans, sewage pumping stations, chemical manufacturing plants, hospitals, mortuaries and plating plants;
   (D)   In the case of any premises where there are uncontrolled cross-connections, either actual or potential, the public water system shall be protected by an approved air-gap separation or an approved reduced pressure principle backflow prevention assembly at the service connection;
   (E)   In the case of any premises where, because of security requirements or other prohibitions or restrictions, it is impossible or impractical to make a complete in-plant cross-connection survey, the public water system shall be protected against backflow from the premises by either an approved air-gap separation or an approved reduced pressure principle backflow prevention assembly on each service to the premises;
   (F)   In the case of any premises having a lawn irrigation system, the public water system shall be protected by an approved pressure vacuum breaker backflow prevention assembly or an approved reduced pressure principle backflow prevention assembly;
   (G)   In the case of any premises having a fire service line, the public water supply system shall be protected by an approved double detector check valve assembly;
   (H)   All other premises not covered in divisions (A) through (G) shall be required to install a non-testable dual check valve assembly for the protection of the public water system; and
   (I)   Existing installations are not exempt from current rules and regulations in this subchapter.
(Ord. 14-011, passed 11-5-14)