(A)The hearing officer may, upon the request of an interested party, or upon his or her own motion and within his or her discretion, at any time, issue subpoenas to compel the attendance and testimony of witnesses and production of books, records, documents and other written evidence at any hearing. If an interested party desires the issuance of subpoenas in order to compel the attendance of witnesses or the production of evidence at a scheduled hearing, the request must be received in writing by the hearing officer at least five workdays in advance of the date of the hearing in order to allow sufficient time for preparation and service of the subpoenas. In the event that the number of subpoenas requested by any party appears to be unreasonable, the hearing officer may require a showing of necessity therefor, and, in the absence of such showing, may limit the number of subpoenas.

(B)Service of subpoenas shall be made by registered or certified mail with return receipt requested or by personal service of an authorized agent. Proof of service shall be evidenced by the return of such receipt or by affidavit of service.