23 CAR § 465-704. Periodic meter tests

(a) Each water utility shall perform periodic accuracy tests on meters as follows: (1) One inch (1”) or less — every twenty (20) years; or (2) Larger than one inch (1”) — every eight (8) years. (b) Each water utility shall test the registration accuracy of a meter at no charge to the customer if the meter has not been tested for a period greater than that indicated below: (1) Five-eighths inch (5/8”) meter — ten (10) years; (2) Three-fourths inch (3/4”) meter — eight (8) years; (3) One inch (1”) meter — six (6) years; or (4) Meters larger than one inch (1”) — four (4) years.