A formal hearing that the commission has power to hold may be held by or before a hearing panel appointed under AS 42.04.080, a hearing examiner, or an administrative law judge designated for the purpose by the chair of the commission. In appropriate cases, a formal hearing may be held before an arbitrator or mediator designated for the purpose by the commission. The testimony and evidence in a formal hearing may be taken by the panel, by the hearing examiner, by the arbitrator, by the mediator, or by the administrative law judge to whom the hearing has been assigned. A decision of a hearing examiner, an arbitrator, a mediator, or an administrative law judge is not final until approved by the commission. A commissioner who has not heard or read the testimony, including the argument, may not participate in making a decision of a hearing panel. A party may file a petition for reconsideration of, or an administrative appeal of, a decision by a hearing examiner, an arbitrator, a mediator, or an administrative law judge that has been approved by the commission, or a decision of a hearing panel. The full commission shall act on the petition for reconsideration or the appeal. In determining the place of a hearing, the commission shall give preference to holding the hearing at a place most convenient for those interested in the subject of the hearing.