The following discovery methods are authorized: Deposition upon oral examination, written interrogatories, requests for production, and requests for admission. Deposition upon oral examination, written interrogatories, and requests for admission may be used as evidence in the hearing. The attendance of witnesses to a deposition may be compelled by use of a subpoena. Depositions will be taken in accordance with this rule and the rules on subpoenas, unless board staff and the respondent stipulate to other arrangements.