Sch 15 para 4
(1) A person is within this paragraph (subject to paragraph 11) if— (a) he is a Crown servant; (b) his sole or main role is to work in support of any of Her Majesty's forces; and (c) either— (i) he is in a designated area, and his normal place of work in that role is in that designated area; or (ii) sub-paragraph (i) does not apply, but he is in a designated area and he came there wholly or partly for the purposes of his work in that role. (2) In this paragraph “ Crown servant ” means a person employed by or in the service of the Government of the United Kingdom.