Any evidence which is sufficiently reliable and probative to support a decision under the provisions of the Administrative Procedure Act, or which would be admissible under the general statutes of the United States, or under the rules of evidence governing proceedings in matters not involving trial by jury in the courts of the United States, will be admissible in hearings before the Board. The rules of evidence will be applied in any proceeding to the end that necessary and proper evidence will be conveniently, inexpensively, and speedily produced, while preserving the substantial rights of the parties.
49 C.F.R. §1114.1