As used in this chapter, unless the context otherwise requires:
(1) “Commission” means the Tennessee public utility commission;
(2) “Contested case” means all proceedings before the commission in which the legal rights, duties, or privileges of specific parties are determined after a hearing before the commission; provided, that the fixing of rates shall be deemed a contested case rather than a rule-making proceeding; and
(3) “Rule” means every regulation, or statement of policy, or interpretation of general application and future effect, including the amendment or repeal thereof, adopted by the commission, whether with or without a prior hearing, to implement or make specific the laws enforced or administered by it, or to govern its organization or procedures, but does not include regulations concerning only the internal management of the commission which do not directly affect the rights or procedures available to the public.