A. In the case of any premises where there is an auxiliary water supply which is not otherwise subject to the provisions of this chapter, the city water system shall be protected by an approved air gap (AG) separation or an approved reduced pressure principle (RPP) backflow prevention device.
B. In the case of any premises where there is any water or substance that would be objectionable, but not hazardous to public health if introduced into the public water system, the public water system shall be protected by an approved double check valve (DCV) assembly.
C. In the case of any premises where there is any material dangerous to health, which is handled in such a fashion as to create an actual or potential hazard to the city water system, the city water system shall be protected by an approved air gap (AG) separation or an approved reduced pressure principle (RPP) backflow prevention device, i.e., sewage treatment plants, pumping stations, chemical plants, hospitals and mortuaries.
D. In the case of any premises where there are "uncontrolled" cross connections, either actual or potential, the city water system shall be protected by an approved air gap (AG) separation or an approved reduced pressure principle (RPP) backflow prevention device 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 impracticable to make a complete in plant cross connection survey, the city water system shall be protected against backflow or backsiphonage from the premises by the installation of an approved backflow prevention device in the service line. In this case, maximum protection will be required; that is, an approved air gap (AG) separation or a reduced pressure principle (RPP) backflow prevention device shall be installed in each service to the premises.
F. In the case of premises having any internal cross connection that cannot be permanently corrected and controlled, or intricate plumbing and piping arrangements, or where entry to all portions of the premises is not readily accessible for inspection purposes, making it impracticable or impossible to ascertain whether or not dangerous cross connections exist, the city water system shall be protected against backflow from the premises by installing an approved air gap (AG) separation or reduced pressure principle (RPP) backflow prevention device in the service. (Ord. 2009-02, 7-28-2009)