RPZ Valves

RPZ valve requirements can be met by reviewing the following guidelines. Local municipalities may require more then these state guidelines so please check with your local government office.

Illinois Department of Public Health, Office of Health Protection
General Inquiries: 217/782-4977
Office of Health Protection: 217/782-3984
Plumbing Program Policy #13

This policy addresses the Illinois Department of Public Health general responsibilities and regulations regarding protection of the potable water supply pertaining to dental offices and clinics. The Department is charged with the oversight of the safety of these facilities, and with the construction, maintenance, code of standards, installation and operation of plumbing.

One of the principal duties under this charge is the determination of the safety of specific equipment and appurtenances connected to the potable water supply system. In order to make these determinations, the Department evaluates the potential hazard posed by the equipment, and discovers whether or not the equipment is properly protected by approved means as an integral part of the equipment.

In order to evaluate the issue of dental units, the Department included both its plumbing professionals and its doctors of dentistry in the evaluation process. The connections posed by dental offices, including potable water to the dental units, vacuum lines and recycler lines, constitute a potential health hazard to the potable water supply system. The various human waste products such as blood, mucous, saliva, secretions, tissue, and possible infection discharged from a person's mouth during dental processes are viewed as potential health hazards which should not be exposed to patients or allowed to contaminate the potable water supply.

There is no industry standard for backflow protection on dental units which would prevent potential contaminating substances from entering the potable water supply system under certain hydraulic conditions; however, realizing that new dental units utilize handpieces and pistol grip type air/water syringes containing a single check valve and the handpiece water outlet and air/water syringe are not submerged in any unknown sources of liquid, the Department has determined the following.

Backflow protection will be required as part of all new or remodeled work. The Department has determined that one reduced pressure principle backflow preventor assembly conforming to A.S.S.E. 1013, or a fixed air gap, shall be used on each dental unit or on the group of dental units and, to the extent practicable, the plumbing for the dental units shall be separated from the plumbing system for the remainder of the building. In addition, a reduced pressure principle backflow preventor assembly or a fixed air gap shall separate the vacuum system from the potable water supply and the dental units.

If the dental unit has a water outlet below the flood rim level of a cuspidor, then an approved reduced pressure principle backflow preventor assembly, a proper fixed air gap, an air vent hole on the water outlet, or an approved vacuum breaker shall protect the water supply from each dental unit.