Regulations for the Navy Part IICentral Regulations · 1957
(1) The sentence of imprisonment may be rigorous or simple, or partly rigorous and partly simple
(2) The Commanding officer, in awarding sentence of imprisonment, shall not direct that the prisoner shall be kept in solitary confinement during any period of his imprisonment.
(3) A sentence of simple imprisonment shall not be ordinarily awarded except in cases where the proper Medical Officer certifies that the offender is not in a fit physical condition to undergo rigorous imprisonment.