A fire hydrant that is directly connected to a water main which is accessible to the public does not require an assembly for the prevention of backflow unless the supplier of water determines that the lack of an assembly for the prevention of backflow presents a hazard to the public water system. If the supplier of water determines there is such a hazard to the public water system, the supplier of water must require the installation of an assembly for the prevention of backflow where the fire hydrant connects to the water main which is commensurate with the degree of hazard that exists in accordance with the requirements of this section and NAC 445A.67185 to 445A.67255, inclusive.
Nev. Admin. Code § 445A.67192