(a) Except as provided in this section, if the director determines that preparation of plans and specifications is necessary and practical for the purchase of goods, general services, or facility construction, the director shall require the preparation of the plans and specifications in cooperation with the department concerned. The plans and specifications must be approved by the director of the department concerned. If the plans and specifications are approved, the director shall keep a copy of the plans and specifications on file in the director's office and make the copy available for public inspection in accordance with the state law requirements governing the retention of records. The director may dispose of any plans and specifications that have been on file in the director's office in accordance with the state law requirements governing the disposal of records.