5 29. The following shall always be determined by the law or by the regulation of the competent administrative authority: ( a ) Conduct constituting a disciplinary offence; ( b ) The types and duration of punishment which may be inflicted; ( c ) The authority competent to impose such punishment. 30. (1) No prisoner shall be punished except in accordance with the terms of such law or regulation, and never twice for the same offence. (2) No prisoner shall be punished unless he has been informed of the offence alleged against him and given a proper opportunity of presenting his defence. The competent authority shall conduct a thorough examination of the case. (3) Where necessary and practicable the prisoner shall be allowed to make his defence through an interpreter. 31. Corporal punishment, punishment by placing in a dark cell, and all cruel, inhuman or degrading punishments shall be completely prohibited as punishments for disciplinary offences. 32. (1) Punishment by close confinement or reduction of diet shall never be inflicted unless the medical officer has examined the prisoner and certified in writing that he is fit to sustain it. (2) The same shall apply to any other punishment that may be prejudicial to the physical or mental health of a prisoner. In no case may such punishment be contrary to or depart from the principle stated in rule 31. (3) The medical officer shall visit daily prisoners undergoing such punishments and shall advise the director if he considers the termination or alteration of the punishment necessary on grounds of physical or mental health. Instruments of restraint 33. Instruments of restraint, such as handcuffs, chains, irons and strait-jackets, shall never be applied as a punishment. Furthermore, chains or irons shall not be used as restraints. Other instruments of restraint shall not be used except in the following circumstances: ( a ) As a precaution against escape during a transfer, provided that they shall be removed when the prisoner appears before a judicial or administrative authority; ( b ) On medical grounds by direction of the medical officer; ( c ) By order of the director, if other methods of control fail, in order to prevent a prisoner from injuring himself or others or from damaging property; in such instances the director shall at once consult the medical officer and report to the higher administrative authority. 34. The patterns and manner of use of instruments of restraint shall be decided by the central prison administration. Such instruments must not be applied for any longer time than is strictly necessary. Information to and complaints by prisoners 35. (1) Every prisoner on admission shall be provided with written information about the regulations governing the treatment of prisoners of his category, the disciplinary requirements of the institution, the authorized methods of seeking information and making complaints, and all such other matters as are necessary to enable him to understand both his rights and his obligations and to adapt himself to the life of the institution.