4(1)A person does not contravene section 39(1)(a) or (c) or (2)(b) by applying in relation to service in the armed forces a relevant requirement if the person shows that the application is a proportionate means of ensuring the combat effectiveness of the armed forces.
(2)A relevant requirement is—
(a)a requirement to be a man;
(b)a requirement not to be a transsexual person.
(3)This Part of this Act, so far as relating to age or disability, does not apply to service in the armed forces; and section 55, so far as relating to disability, does not apply to work experience in the armed forces.