8A vehicle which is made available by the Secretary of State—
(a)to a person, body or local authority under section 23 or 26 of the [1977 c. 49.] National Health Service Act 1977, or
(b)to a local authority, education authority or voluntary organisation in Scotland under section 15 or 16 of the National Health Service (Scotland) Act 1978,
and which is used in accordance with the terms on which it is so made available is an exempt vehicle.