Maryland Code, Environment § 12-306

(a) Except as otherwise provided in this section, certification authorizes a waterworks, wastewater works, or industrial wastewater works to employ the certified individual as an operator, industrial operator, or superintendent in an appropriate job classification.

(b) Certification as an operator authorizes the operator to perform tasks assigned by a certified superintendent, if an operator is not prohibited from performing those tasks by the rules and regulations adopted under this title.

(c) The Secretary shall adopt rules and regulations to classify or certify superintendents, operators, and industrial operators to perform certain tasks in waterworks, wastewater works, and industrial wastewater works.