2 7. (1) In every place where persons are imprisoned there shall be kept a bound registration book with numbered pages in which shall be entered in respect of each prisoner received: ( a ) Information concerning his identity; ( b ) The reasons for his commitment and the authority therefor; ( c ) The day and hour of his admission and release. (2) No person shall be received in an institution without a valid commitment order of which the details shall have been previously entered in the register. Separation of categories 8. The different categories of prisoners shall be kept in separate institutions or parts of institutions taking account of their sex, age, criminal record, the legal reason for their detention and the necessities of their treatment. Thus, ( a ) Men and women shall so far as possible be detained in separate institutions; in an institution which receives both men and women the whole of the premises allocated to women shall be entirely separate; ( b ) Untried prisoners shall be kept separate from convicted prisoners; ( c ) Persons imprisoned for debt and other civil prisoners shall be kept separate from persons imprisoned by reason of a criminal offence; ( d ) Young prisoners shall be kept separate from adults. Accommodation 9. (1) Where sleeping accommodation is in individual cells or rooms, each prisoner shall occupy by night a cell or room by himself. If for special reasons, such as temporary overcrowding, it becomes necessary for the central prison administration to make an exception to this rule, it is not desirable to have two prisoners in a cell or room. (2) Where dormitories are used, they shall be occupied by prisoners carefully selected as being suitable to associate with one another in those conditions. There shall be regular supervision by night, in keeping with the nature of the institution. 10. All accommodation provided for the use of prisoners and in particular all sleeping accommodation shall meet all requirements of health, due regard being paid to climatic conditions and particularly to cubic content of air, minimum floor space, lighting, heating and ventilation. 11. In all places where prisoners are required to live or work, ( a ) The windows shall be large enough to enable the prisoners to read or work by natural light, and shall be so constructed that they can allow the entrance of fresh air whether or not there is artificial ventilation; ( b ) Artificial light shall be provided sufficient for the prisoners to read or work without injury to eyesight. 12. The sanitary installations shall be adequate to enable every prisoner to comply with the needs of nature when necessary and in a clean and decent manner. 13. Adequate bathing and shower installations shall be provided so that every prisoner may be enabled and required to have a bath or shower, at a temperature suitable to the climate, as frequently as