13. (1) The Chairman, with the consent of the Board, may authorize the Vice-Chairman by an order in writing to exercise any of the powers conferred or to perform any of the duties imposed on the Chairman by this Act, and thereupon the responsibility of the Chairman in respect of such powers and duties shall devolve upon the Vice-Chairman during the continuance of such order.(2) When the office of Chairman is vacant, the Vice-Chairman shall exercise the functions of the Chairman until a new Chairman is appointed.