12VAC5-590-630. Backflow prevention assemblies, devices, and backflow elimination methods for containment.
A. Any backflow prevention assembly or backflow elimination method or backflow prevention device shall be of the approved type and shall comply with the USBC.
B. General safeguards
1. The backflow prevention assembly or backflow elimination method or backflow elimination device used shall depend on the degree of hazard that exists or may exist. The safeguard shall ensure maintenance of the distribution system water quality and its usefulness.
2. The degree of hazard, either high or low, is based on (i) the nature of the contaminant; (ii) the potential of the health hazard; (iii) the potential method of backflow (either by backpressure or by backsiphonage); and (iv) the potential effect on waterworks structures, equipment, and appurtenances used in the storage, collection, purification, treatment, and distribution of potable water. Table 630.1 shall be used as a guide to determine the degree of hazard for any situation.
Table 630.1 | |
Cross-connections that meet or may meet the following conditions shall be rated at the corresponding degree of hazard. | |
High Hazard | Low Hazard |
The contaminant would be toxic, poisonous, noxious, unhealthy, or of unknown quality. | The contaminant would only degrade the quality of the water aesthetically or impair the usefulness of the water. |
A health hazard would exist. | A health hazard would not exist. |
The contaminant would disrupt the service of piped water for human consumption. | The contaminant would not disrupt service of piped water for human consumption. |
Backflow would be by either backpressure or backsiphonage. | Backflow would occur by backsiphonage. |
Examples: lawn irrigation systems, fire sprinkler systems with chemical additives or antifreeze, sewage, used water, nonpotable water, auxiliary water systems, and mixtures of water and other liquids, gases, or other chemicals. | Examples: food residuals, coffee machines, non-carbonated beverage dispensers, and residential fire sprinkler systems constructed of materials designed for potable water flow. |
3. The USBC and the manufacturer's specifications shall be used to determine the appropriateness of the backflow prevention assembly or backflow prevention device application for containment.
C. Owners shall not allow the installation of backflow prevention devices or backflow prevention assemblies with openings, outlets, or vents that are designed to operate or open during backflow prevention:
1. In areas subject to flooding or in pits;
2. In areas with atmospheric conditions that represent a contamination threat to the potable water supply; and
3. In such a manner as to be able to be bypassed.
D. Starting January 1, 2023, persons testing and repairing backflow prevention assemblies and backflow prevention devices shall be certified by a Commonwealth of Virginia tradesman certification program (identified by DPOR as backflow prevention device workers). Until January 1, 2023, persons testing and repairing backflow prevention assemblies and backflow prevention devices shall be qualified to perform such work as demonstrated by possessing a certification or license from a local or state agency having legal authority or shall possess a certificate of completion of applicable vocational training acceptable to the owner.
Statutory Authority
§§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from VR355-18-006.06 § 2.30, eff. August 1, 1991; amended, Virginia Register Volume 9, Issue 17, eff. June 23, 1993; Volume 31, Issue 1, eff. October 10, 2014; Volume 37, Issue 20, eff. June 23, 2021.