1) Provisions for combination air relief shall be provided at all high points of waterlines. Where possible, location of service taps at high points in the line is preferable to the installation of an air relief valve.

2) Where service taps cannot be used, an air release valve shall be permanently installed at high points on all water mains at all location where air can accumulate. An automatic air release valve shall be installed in a meter box or vault outside of the street at a location where flooding of the meter box or vault will not occur.

1) The open end of an air release pipe from automatic valves shall extend to the top of the meter box or vault at least twelve inches above grade and provided with a screened, downward facing vent opening. Grade shall mean the existing ground elevation adjoining the meter box or vault.