Geneva Convention (IV): Relative to the Protection of Civilian Persons, Part III, Section 4, Chapter II
The Detaining Power shall not set up places of internment in areas particularly exposed to the dangers of war.
The Detaining Power shall give the enemy Powers, through the intermediary of the Protecting Powers, all useful information regarding the geographical location of places of internment.
Whenever military considerations permit, internment camps shall be indicated by the letters IC, placed so as to be clearly visible in the daytime from the air. The Powers concerned may, however, agree upon any other system of marking. No place other than an internment camp shall be marked as such.
Internees shall be accommodated and administered separately from prisoners of war and from persons deprived of liberty for any other reason.
The Detaining Power is bound to take all necessary and possible measures to ensure that protected persons shall, from the outset of their internment, be accommodated in buildings or quarters which afford every possible safeguard as regards hygiene and health, and provide efficient protection against the rigours of the climate and the effects of the war. In no case shall permanent places of internment be situated in unhealthy areas or in districts the climate of which is injurious to the internees. In all cases where the district, in which a protected person is temporarily interned , is in an unhealthy area or has a climate which is harmful to his health, he shall be removed to a more suitable place of internment as rapidly as circumstances permit.
The premises shall be fully protected from dampness, adequately heated and lighted, in particular between dusk and lights out. The sleeping quarters shall be sufficiently spacious and well ventilated, and the internees shall have suitable bedding and sufficient blankets, account being taken of the climate, and the age, sex, and state of health of the internees.
Internees shall have for their use, day and night, sanitary conveniences which conform to the rules of hygiene and are constantly maintained in a state of cleanliness. They shall be provided with sufficient water and soap for their daily personal toilet and for washing their personal laundry; installations and facilities necessary for this purpose shall be granted to them.
Showers or baths shall also be available. The necessary time shall be set aside for washing and for cleaning.
Whenever it is necessary, as an exceptional and temporary measure, to accommodate women internees who are not members of a family unit in the same place of internment as men, the provision of separate sleeping quarters and sanitary conveniences for the use of such women internees shall be obligatory.
The Detaining Power shall place at the disposal of interned persons, of whatever denomination, premises suitable for the holding of their religious services.
Canteens shall be installed in every place of internment, except where other suitable facilities are available. Their purpose shall be to enable internees to make purchases, at prices not higher than local market prices, of foodstuffs and articles of everyday use, including soap and tobacco, such as would increase their personal well-being and comfort.
Profits made by canteens shall be credited to a welfare fund to be set up for each place of internment, and administered for the benefit of the internees attached to such place of internment. The Internee Committee provided for in Article 102 shall have the right to check the management of the canteen and of the said fund.
When a place of internment is closed down, the balance of the welfare fund shall be transferred to the welfare fund of a place of internment for internees of the same nationality, or, if such a place does not exist, to a central welfare fund which shall be administered for the benefit of all internees remaining in the custody of the Detaining Power. In case of a general release, the said profits shall be kept by the Detaining Power, subject to any agreement to the contrary between the Powers concerned.
In all places of internment exposed to air raids and other hazards of war, shelters adequate in number and structure to ensure the necessary protection shall be installed. In case of alarms, the internees shall be free to enter such shelters as quickly as possible, excepting those who remain for the protection of their quarters against the aforesaid hazards. Any protective measures taken in favour of the population shall also apply to them.
All due precautions must be taken in places of internment against the danger of fire.