(a) In general. A witness, including an expert witness, who testifies at a deposition or hearing will be paid the same fees for attendance and mileage as are paid in the United States district courts in proceedings in which the United States is a party, except as provided in paragraph (b) and unless otherwise waived.

(b) Exception for testimony by a party. In the case of testimony by a party, no witness fees or mileage need to be paid. The Board will not be required to pay any fees to, or expenses of, any witness not subpoenaed by the Board.

(c) Timing of payment. Fees and mileage in accordance with this paragraph (c)must be paid in advance by the party requesting the subpoena, except that fees and mileage need not be tendered in advance where the Board is the party requesting the subpoena.