12.—(1) Any of the following who have travelled to the United Kingdom in the course of their work—
(a)drivers and crews on shuttle services and on services for the carriage of passengers or goods by way of the tunnel system,
(b)operational, rail maintenance, safety and security workers working on the tunnel system,
(c)other workers carrying out essential roles for the safe or efficient operation of the tunnel system, shuttle services or services for the carriage of passengers or goods by way of the tunnel system, or relating to the security of the tunnel system or any such services.
(2) For the purposes of sub-paragraph (1)—
(a)“shuttle service” has the meaning given in section 1(9) of the Channel Tunnel Act 1987,
(b)“tunnel system” has the meaning given in section 1(7) of that Act.