24.—(1) The Governor may impose special security measures on a prisoner on a provisional basis without having recourse to the procedure contained in rule 23 where the Governor considers that the immediate provisional imposition of the measures is necessary—
(a)in the interests of the health, welfare or safety of the prisoner or any other person; or
(b)to prevent an escape from legal custody or the doing of any act prejudicial to the safe keeping of persons in legal custody.
(2) Special security measures may only be provisionally imposed on a prisoner under paragraph (1) where—
(a)the prisoner is informed in writing of the provisional imposition of the special security measures; and
(b)the procedure contained in rule 23 is commenced within 48 hours of the provisional imposition of the special security measures.
(3) If the Governor decides that the provisional imposition of the special security measures does not require to extend beyond a 48 hour period—
(a)the prisoner must be informed in writing, within 24 hours of the Governor’s decision, that the special security measures are no longer provisionally imposed; and
(b)there is no requirement to follow the procedure contained in rule 23.