Maryland Code, Public Utilities § 7-302

(a)(1) By written request, a consumer may compel the Commission to inspect and test the consumer's electric meter or gas meter.

(2) The consumer is entitled to be present for the test.

(b)(1) The Commission shall set a percentage tolerance limit for the accuracy of an electric meter or gas meter.

(2) The Commission shall order a gas company or electric company to replace a meter at the company's expense if the meter is incorrect to the prejudice of the consumer by more than the percentage tolerance limit set by the Commission.

(c)(1) The Commission shall set a uniform reasonable fee for meter test services under this section.