.02 Working Standards.

A. Requirements. Each meter shop maintained or designated by a utility shall have at least one calibrated tank for volumetric measurement or a tank mounted upon scales for weight measurement. The tank shall be of sufficient capacity to insure an acceptable determination of the accuracy of the utilities' meters.

B. Calibration. Working standards shall be checked periodically (see Regulation .09B of this chapter) by comparison with approved secondary standards.

C. Certificates. Each standard shall be accompanied at all times by a certificate or calibration card, duly signed and dated, on which are recorded the corrections required to compensate for errors found at the customary test points at the time of the last previous test.

D. Care in Handling. Extreme care shall be exercised in the use and handling of standards to assure that their accuracy is not disturbed.