1. (1) Meters and/or associated metering devices shall be tested at the points and adjusted to the tolerances prescribed below. The test of any unit of metering equipment shall consist of a comparison of its accuracy with the accuracy of a standard. The Commission will use the applicable provisions of the standards listed in Rule 1220-04-05- .22 as criteria of accepted good practice in testing meters.

   1. (a) Positive Displacement Meters

      1. 1. Accuracy at test points Flow Adjusted to within Check flow………………………………………………..…….…………….…….1.5% Not less than full rated flow …………………………………….………………...1.5%
      2. 2. Overall accuracy The accuracy at check flow and the accuracy at not less than full rated flow shall agree with one (1%) percent.
   2. (b) Orifice Meters Testing for all orifice meters shall be in accordance with procedures as set forth in the American Gas Association Committee Report No. 3. Accuracy at test points must be within two percent (2%), 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 so that the timing element is not in error by more than plus or minus four (4) minutes in twenty- four (24) hours.

   4. (d) General

      1. 1. All meters and/or associated metering devices, when tested, shall be adjusted as closely as practicable to the condition of zero (0) error.
      2. 2. All tolerances are to be interpreted as maximum permissible variations from the condition of zero (0) error. In making adjustments no advantage of the prescribed tolerance limits shall be taken

Authority: T.C.A. § 65-2-102. Administrative History: Original rule certified May 9, 1974. Editorial changes made by the Secretary of State pursuant to Public Chapter 305 of 1995; “Commission” and references to the “Commission” were changed to “Authority” and references to the “Authority”; effective March 28, 2003. Administrative changes made to this chapter on April 27, 2018 pursuant to Public Chapter 94 of 2017; “Tennessee Regulatory Authority” references were changed to “Tennessee Public Utility Commission,” “Authority” references were changed to “Commission,” “Authority Director” references were changed to “Commissioner,” and “Chief” references were changed to “Director.”