No person shall be appointed to, or continue in, the office of the member of a Tribunal or National Industrial Tribunal, respectively, if—
(a) he is not an independent person; or
(b) he has attained the age of sixty-five years.
Explanation.—For the purposes of this section "independent person" means a person who is unconnected with the industrial dispute referred to a Tribunal or National Industrial Tribunal or with any industry directly affected by such dispute.