17. Except in so far as in any particular case any immunity or privilege is waived by the Director, experts (other than officers of the Fund) shall, so far as is necessary for the carrying out of their functions, including during journeys made in carrying out their functions and in the course of missions for the Fund, enjoy:—
(a)immunity from suit and legal process in respect of acts done by them in the exercise of their functions, including words written or spoken, except in the case of a motor traffic offence committed by an expert or in the case of damage caused by a motor vehicle belonging to or driven by him;
(b)while exercising their functions in connection with the Fund or in carrying out missions for the Fund, the like inviolability for all their official papers and documents as is accorded to a diplomatic agent.