1. 1. Pre-Installation Inspection.

   1. a. Every meter and/or associated metering device shall be inspected and sealed before being placed in service.
   2. b. New or reconditioned meters which have been sealed at the factory need not be resealed in the shop of the gas utility.
2. 2. Post-Removal Inspection and Tests. All meters and/or associated metering devices shall be tested when returned to the meter shop prior to being placed back in service.

3. 3. Leak Tests. Every meter shall be leak tested prior to installation.

   1. a. Each new meter must have been tested by the manufacturer to a minimum of ten p.s.i.g.
   2. b. Meters removed from service and returned to the meter shop shall, prior to being placed back in service, be tested and subjected to an internal pressure of 1.1 times the maximum operating pressure of the meter and checked for the presence of leaks by one of the tests listed under subsection 4 below.

   3. c. Acceptable Leak Tests.

      1. (1) Immersion Tests.
      2. (2) Soap Tests.
      3. (3) Pressure drop test of a type acceptable to the commission.

4. 4. Operating Pressure Limitations.

   1. A. A meter may not be used at a pressure that is more than sixty-seven percent of the manufacturer’s shell test pressure.
   2. B. A rebuilt or repaired tinned steel case meter may not be used at a pressure that is more than fifty percent of the pressure used to test the meter after rebuilding or repairing.

5. 5. Method of Testing. All tests to determine the accuracy of registration of any gas service meter shall be made with a suitable meter prover.

   1. a. Diaphragm, Displacement, Rotary, and Turbine Meters

      1. (1) Accuracy at Test Points.

         FLOW	ADJUSTED TO WITHIN
         Check Flow (20% of rated meter capacity)	98.5%—100.5%
         Full Flow (Equal to or in excess of operating load requirement)	98.5%—100.5%

      2. (2) Actual Accuracy.

         The accuracy as determined by averaging the results at the check and open rated flow.

      3. (3) Overall Accuracy.

         The accuracy at a check flow and the accuracy at not less than open rated flow shall agree within one percent.

   2. b. Orifice Meters.

      Accuracy at test points must be within one-half of one percent plus or minus.

   3. c. Timing Devices.

      All recording type meters or associated instruments which have a timing element that serves to record the time at which the measurement occurs must be adjusted as far as practicable so that the timing element is not in error by more than plus or minus five minutes in twenty-four hours.

   The tests of any unit of metering equipment shall consist of a comparison of its accuracy with the accuracy of a standard. The ORS will use the applicable provisions of the standards listed in 103-461 as criteria of accepted good practice in testing meters.

   All meters and/or associated metering devices, when tested, shall be adjusted as closely as possible to the condition of zero error. All tolerances listed below are to be interpreted as maximum permissible variations from the condition of zero error.

HISTORY: Amended by State Register Volume 32, Issue No. 5, eff May 23, 2008.