1. (a) Only approved backflow prevention devices shall be used.

2. (b) Only the types of backflow prevention devices listed in Table 505-1 below shall be used for the containment of on-premise hazards for low and high degree of hazard situations respectively:

   Table 505-1: Acceptable Backflow Prevention Devices for Degrees of Hazards

   Low Degree of Hazard

   High Degree of Hazard

   Air gap

   Air gap

   Pressure vacuum breaker

   Reduced pressure principal backflow prevention device assembly

   Double check valve

   A combination of the above

   Reduced pressure principal backflow prevention device assembly

   A combination of the above

3. (c) A backflow prevention device shall not be installed in a location where it will:

   1. (1) Be subject to corrosive fumes, grit, or sticky or abrasive liquids;
   2. (2) Be subject to flooding or mechanical abuse;
   3. (3) Not be easily accessible for testing and repair;
   4. (4) Be in a pit or built into or close to walls or other obstructions; or
   5. (5) Be in a vertical position unless the backflow prevention device was certified for that orientation.

Source. (See Revision Note at part heading for Env-Dw 505) #10615, eff 6-1-14; ss by #14120, eff 11-23-24, EXPIRES: 11-23-34