A potable water supply system shall be designed, installed and maintained in such a manner so as to prevent contamination from nonpotable liquids, solids or gases being introduced into the potable water supply through cross-connections or any other piping connections to the system. Backflow preventer applications shall conform to Table 18-29-608.1.
For a printer-friendly PDF version of Table 18-29-608.1, please click here.
Device | Degree of Hazard a | Application b | Applicable Standards |
Device | Degree of Hazard a | Application b | Applicable Standards |
Air gap c |
High or low hazard | Backsiphonage or backpressure | ASME A112.1.2 |
Antisiphon-type Water Closet Flush Tank Ball Cock | Low Hazard | Backsiphonage only | ASSE 1002 CSA CAN/CSA B125 |
Reduced Pressure Principle Backflow Preventer | High or low hazard | Backpressure or backsiphonage Sizes 1/4" to 10" | ASSE 1013 AWWA C511 CSA CAN/CSA B64.4 |
Reduced Pressure Detector Assembly Backflow Preventer | High or low hazard | Backsiphonage or backpressure | ASSE 1047 |
Double Check Backflow Prevention Assembly | Low hazard | Backpressure or backsiphonage Sizes 3/8" to 16" | ASSE 1015 AWWA C510 |
Double Check Detector Backflow Preventer Assembly | Low hazard | Backpressure or backsiphonage (Fire sprinkler systems) Sizes 1 1/2" - 16" | ASSE 1048 |
Dual Check Valve-Type Backflow Preventer | Low hazard | Backpressure or backsiphonage Sizes 1/4" - 1" | ASSE 1024 |
Backflow Preventer with Intermediate Atmospheric Vents | Low hazard | Backpressure or backsiphonage Sizes 1/4" - 3/4" | ASSE 1012 CSA CAN/CSA B64.3 |
Dual Check Valve-Type Backflow Preventer for Carbonated Beverage Dispensers/Post Mix Type | Low hazard | Backpressure or backsiphonage Sizes 1/4" - 3/8" | ASSE 1032 |
Pipe-Applied Atmospheric-Type Vacuum Breaker | High or low hazard | Backsiphonage only Sizes 1/4" - 4" | ASSE 1001 CSA CAN/CSA B64.1.1 |
Pressure Vacuum Breaker Assembly | High or low hazard | Backsiphonage only Sizes 1/2" - 2" | ASSE 1020 |
Hose-connection Vacuum Breaker | High or low hazard | Backsiphonage Sizes 1/2", 3/4", 1" | ASSE 1011 CSA CAN/CSA B64.2 |
Vacuum Breaker Wall Hydrants, Frost-Resistant, Automatic Draining Type | High or low hazard | Backsiphonage Sizes 3/4", 1" | ASSE 1019 CSA CAN/CSA B64.2.2 |
Laboratory Faucet Backflow Preventer (Non-testable) | Low hazard | Backsiphonage | ASSE 1035 CSA B64.7 |
Hose Connection Backflow Preventer (Non-testable) | Low hazard | Low head backpressure, rated working pressure backpressure or backsiphonage Sizes 1/2" - 1" | ASSE 1052 |
Spill-proof vacuum breaker | High or low hazard | Backsiphonage only Sizes 1/4" - 2" | ASSE 1056 |
For SI: 1 inch = 25.4 mm.
a. Low Hazard - See Pollution (Section 202) and Department of Water Management requirements
High Hazard - See Contamination (Section 202) and Department of Water Management requirements
b. See Backpressure (Section 202)
See Backpressure, Low Head (Section 202)
See Backsiphonage (Section 202)
c. Break tank
d. For systems using non-food grade chemical additives
(Amend Coun. J. 11-8-12, p. 38872, § 353)