(a) Upon the initiation of an official investigation, complaints shall be classified into one or more of the following complaint categories:(1) Complaints alleging acts or omissions that may constitute a continuing or imminent threat to the public welfare;(2) Complaints that require medical expertise to review;(3) Complaints that do not require medical expertise to review; or(4) Complaints alleging the practice of veterinary medicine or equine dentistry without a license.(b) The complainant and respondent shall be notified of the projected time requirements for the complaint, unless the notice would jeopardize an investigation.(c) The executive director may approve the use of a private investigator to assist in the investigation of a complaint where the use of Board investigators is not feasible or economical or where private investigators could provide valuable assistance to the Board investigators.