An employee shall submit to examination by a medical officer of the United States, or by a physician designated or approved by the Secretary of Labor, after the injury and as frequently and at the times and places as may be reasonably required. The employee may have a physician designated and paid by him present to participate in the examination. If there is disagreement between the physician making the examination for the United States and the physician of the employee, the Secretary shall appoint a third physician who shall make an examination.

An employee is entitled to be paid expenses incident to an examination required by the Secretary which in the opinion of the Secretary are necessary and reasonable, including transportation and loss of wages incurred in order to be examined. The expenses, when authorized or approved by the Secretary, are paid from the Employees’ Compensation Fund.

The Secretary shall fix the fees for examinations held under this section by physicians not employed by or under contract to the United States to furnish medical services to employees. The fees, when authorized or approved by the Secretary, are paid from the Employees’ Compensation Fund.

If an employee refuses to submit to or obstructs an examination, his right to compensation under this subchapter is suspended until the refusal or obstruction stops. Compensation is not payable while a refusal or obstruction continues, and the period of the refusal or obstruction is deducted from the period for which compensation is payable to the employee.