The type of prevention device required depends on the degree of hazard that exists:
A. An air gap separation or reduced principle backflow prevention assembly shall be installed where the water supply may be contaminated by sewage, industrial waste of a toxic nature or other contaminant, which could cause a health or system hazard.
B. In the case of a substance which may be objectionable but not hazardous to health, an air gap separation or a reduced pressure principle backflow prevention assembly, or a double check valve assembly shall be installed.
C. Lawn sprinkler systems, which are supplied by city water only, shall be required to have a double check valve backflow prevention assembly, or a pressure vacuum breaker assembly depending on the design of the sprinkler system and potential risk to the potable water supply. Backflow prevention assemblies larger than one inch (1") will submit design and any approval will be made by the water operator. All backflow prevention assemblies shall be of a type approved by the Idaho department of health and welfare, division of environmental quality. (Ord. 173, 2-13-2013)