(a) Except as provided by Subsection (b), the department and the institution may not communicate with an arbitrator other than at an oral hearing unless the parties and the arbitrator agree otherwise.
(b) Any oral or written communication, other than a communication authorized under Subsection (a), from the parties to an arbitrator shall be directed to the association that is conducting the arbitration or, if there is no association conducting the arbitration, to the State Office of Administrative Hearings, for transmittal to the arbitrator.