17(1)The Secretary of State may, on an application by a person, issue a certificate in respect of the person if satisfied that the person—
(a)is a fit and proper person to perform custodial duties at secure colleges, and
(b)has received training to such standard as the Secretary of State considers appropriate for the performance of those functions.
(2)The certificate must state that it is to cease to be in force on a date or on the occurrence of an event.
(3)Once issued, the certificate continues in force until that date or event, subject to any previous suspension or revocation under paragraph 18 or 19.