While the pressure element is actuated, the mechanism may be driven either manually or by a motor. A dead weight tester or regulated air or gas pressure may be used to actuate the pressure element. If regulated air or gas pressure is used, a pressure gauge having an accuracy of plus or minus one fourth of one percent (+- 0.25%) of full scale shall be used to indicate the pressure on the element.
Each gas corporation shall apply a specific pressure to the pressure element and the uncorrected counter or calibrating mechanism shall be advanced a predetermined number of counts. The number of counts by which the corrected counter or calibrating mechanism has been advanced shall be recorded. The accuracy shall be calculated by comparing the number of counts that the corrected counter or calibrating mechanism has been advanced with the actual number of counts required for the pressure at which the test was made.
Electronic pressure correcting devices shall be calibrated following the manufacturer's recommended procedures.
D.C. Mun. Regs. tit. 15, r. 15-2357