(A) The discharge pipe of an air gap shall terminate:
(1) A minimum of two pipe diameters of the discharge pipe or six inches, whichever is the lesser, above the maximum recorded flood level or above the flood level rim of the receiving vessel, whichever is higher; or
(2) A minimum of three pipe diameters of the discharge pipe or six inches, whichever is the lesser, above the maximum recorded flood level or above the flood level rim of the receiving vessel, whichever is higher where:
(a) A side wall, rib or similar obstruction is spaced closer than three diameters from the piping affecting the air gap; or
(b) Two intersecting walls are located closer than four pipe diameters from the piping affecting the air gap.
(B) Only those models of double check valve assemblies, reduced pressure principle backflow preventers and pressure vacuum breakers that have been listed by the List of Approved Backflow Prevention Assemblies, by the Foundation for cross- connection Control and Hydraulic Research of the University of Southern California, 2-7-2012, or those acceptable under the state’s Plumbing Code under the Fire Prevention and Building Safety Commission rules at 675 I.A.C. 16-1.4, shall be installed.
(C) (1) Reduced pressure principle backflow preventers shall be installed horizontally or vertically as listed by the Foundation for Cross-Connection Control and Hydraulic Research of the University of Southern California, 2-7-2012, with:
(a) No plug or additional piping affixed to the pressure differential relief valve port; and
(b) The pressure differential relief valve port a minimum of 12 inches above floor level.
(2) Additionally, the device must be installed at a location where any leakage from the pressure differential relief valve port will be noticed, and that allows access to the valve for maintenance and testing from floor level, without use of a ladder or other similar temporary apparatus, and that will not subject the device to flooding, excessive heat or freezing.
(D) All double check valve assemblies shall be installed at a location that allows access to the device for maintenance and testing from floor level, without use of a ladder or other similar temporary apparatus, and that will not subject the device to flooding, excessive heat or freezing.
(E) Pressure vacuum breakers shall be installed as near as possible, to the irrigation facility, at a location that allows access to the device for maintenance and testing from floor or ground level, without use of a ladder or other similar temporary apparatus, and that will not subject the device to flooding, excessive heat or freezing. Additionally, the device must be installed between two tightly closing shut-off valves, with its center line or datum point a minimum of 12 inches above:
(1) Floor level;
(2) The highest downstream piping or shut-off valve; and
(3) The highest downstream overflow rim or discharge point.
(Ord. 2018-13, passed 8-13-2018)