(1) An application by an offender for approval under section 55 in relation to a detention period must—
(a) be made to the chief executive, orally or in writing; and
(b) state the grounds on which it is made.
(2) If the application is made on health grounds, it must be accompanied by a doctor's certificate—
(a) indicating the nature or extent of the illness or injury; and
(b) confirming that the offender is unfit to perform periodic detention in the detention period because of the illness or injury.