Each state agency shall adopt rules, consistent with the management plan adopted under § 2171.104, relating to the assignment and use of the agency’s vehicles. The rules must require that:
(1) each agency vehicle, with the exception of a vehicle assigned to a field employee, be assigned to the agency motor pool and be available for checkout; and
(2) an agency may assign a vehicle to an individual administrative or executive employee on a regular or everyday basis only if the agency makes a written documented finding that the assignment is critical to the needs and mission of the agency.