Where a local authority within the meaning of the M1Local Government Act 1933 or the M2Local Government (Scotland) Act 1947 appoint a committee of the authority under any enactment, and the members of the committee include or may include persons who are not members of the authority, then in considering the appointment to the committee of such persons regard shall be had, if the committee is concerned with matters in which the chronically sick or disabled have special needs, to the desirability of appointing to the committee persons with experience of work among and of the needs of the chronically sick and disabled, and to the person or persons with that experience being or including a chronically sick or disabled person or persons.