(1) The facilities of the state's telecommunications systems are provided principally for the conduct of state business. In addition to state business, the state's telecommunications systems may be used by:

(a) local political subdivisions of the state, for the conduct of their business;

(b) residents in housing of the Montana University System, for their calls originating on the university system campuses; and

(c) state employees and officials for local and long distance calls to latch-key children, teachers, doctors, day-care centers and baby sitters, to family members to inform them of unexpected schedule changes, and for other essential personal business. The use of the state's telecommunication systems for essential personal business must be kept to a minimum, and not interfere with the conduct of state business. Essential personal long distance calls must be either collect, charged to a third party nonstate number, or charged to a personal credit card.