Enforcement Rule 206(a) provides that a hearing committee shall act only with the concurrence of a majority of its members and that two members shall constitute a quorum, except that a single senior or experienced hearing committee member may act for the committee when the committee is sitting as an investigatory hearing committee under § 91.2(a)(1) (relating to subpoenas and investigations) or when conducting a prehearing conference.
204 Pa. Code § 93.82