art 16
Except in so far as in any particular case any privilege or immunity is waived by the Organisation, experts (other than officials of the Organisation) shall, so far as is necessary for the effective exercise of their functions, including during journeys made in carrying out their functions and in the course of their missions for the Organisation, enjoy:— (a) the like immunity from personal arrest or detention and from seizure of their personal baggage as is accorded to a diplomatic agent; (b) immunity from suit and legal process (even after the termination of their mission) in respect of acts done by them in the course of the performance of their official functions, including words spoken or written; and (c) the like inviolability for all papers, documents and official material as is accorded to a diplomatic agent.