(1) The Board may, in respect of any particular matter or class of matter, and in writing delegate to the Executive Director or to any other Director or Committee any of its functions under this Act except this power of delegation and the following functions—
(a) approving annual budgets or programme of activities;
(b) making regulations;
(c) carrying out activities which require expenditure not provided in the budget.
(2) Subject to any general direction given to him or her by the Board the person or persons to whom any powers are so delegated may exercise these powers in the same manner and with the same effect as if they had been conferred in him or her directly by this Act and not by delegation.
(3) Every person purporting to act pursuant to a delegation under this section shall, in the absence of proof to the contrary, be presumed to be acting in accordance with the terms of the delegation.
(4) Every delegation under this section shall be revocable and no such delegation shall prevent the exercise of any power by the Board.