20 C.F.R. § 332.7
An employee shall be requested to furnish such information as to any mileage or work restrictions or as to lay-over or stand-by status as may be necessary for the determination of his claim. An employee's statement in connection with his claim that he was not out of service because of a lay-over or stand-by rule or because of a mileage or work restriction shall, in the absence of evidence to the contrary, be accepted as sufficient for a finding on that point. An employee's report of the number of miles or hours' credit earned in rotating extra board, pool, or chain gang service shall, in the absence of evidence to the contrary, be accepted as correct for purposes of determining whether he had the equivalent of full-time work during the period covered by his claim. When it appears clear that an employee in rotating extra board, pool, or chain gang service who fails to report the number of miles or hours' credit earned on days in the period covered by his claim form was not employed on enough days to have had the equivalent of full-time work in the period, no additional information as to mileage or work restrictions shall be deemed necessary for the determination of his claim.
20 C.F.R. § 332.7