–4– reviewed periodically by an independent authority. 87. Arrangements should be made enabling detained irregular migrants to consult a lawyer or a doctor on an ongoing basis, and to receive visits from NGO representatives, family members or other persons of their choice, and to have telephone contact with them. If members of the same family are deprived of their liberty under aliens legislation, every effort should be made to avoid separating them. 88. It is in the interests of both irregular migrants and staff that there be clear house rules for all detention facilities, and copies of the rules should be made available in a suitable range of languages. The house rules should primarily be informative in nature and address the widest range of issues, rights and duties which are relevant to daily life in detention. The house rules should also contain disciplinary procedures and provide detainees with the right to be heard on the subject of violations that they are alleged to have committed, and to appeal to an independent authority against any sanctions imposed. Without such rules, there is a risk of an unofficial (and uncontrolled) disciplinary system developing. In case of the application of a segregation measure for security reasons or for the irregular migrant’s own protection, these procedures should be accompanied by effective safeguards. The person concerned should be informed of the reasons for the measure taken against him/her, be given the opportunity to present his/her views on the matter prior to the measure being implemented, and be able to contest the measure before an appropriate authority. 89. Independent monitoring of detention facilities for irregular migrants is an important element in the prevention of ill-treatment and, more generally, of ensuring satisfactory conditions of detention. To be fully effective, monitoring visits should be both frequent and unannounced. Further, monitoring bodies should be empowered to interview irregular migrants in private and should examine all issues related to their treatment (material conditions of detention, custody records and other documentation, the exercise of detained persons’ rights, health care, etc.). Health-related safeguards 90. The assessment of the state of health of irregular migrants during their deprivation of liberty is an essential responsibility in relation to each individual detainee and in relation to a group of irregular migrants as a whole. The mental and physical health of irregular migrants may be negatively affected by previous traumatic experiences. Further, the loss of accustomed personal and cultural surroundings and uncertainty about one’s future may lead to mental deterioration, including exacerbation of pre-existing symptoms of depression, anxiety and post-traumatic disorder. 91. At a minimum, a person with a recognised nursing qualification must be present on a daily basis at all centres for detained irregular migrants. Such a person should, in particular, perform the initial medical screening of new arrivals (in particular for transmissible diseases, including tuberculosis), receive requests to see a doctor, ensure the provision and distribution of prescribed medicines, keep the medical documentation and supervise the general conditions of hygiene. 92. Obviously, medical confidentiality should be observed in the same way as in the outside community; in particular, irregular migrants’ medical files should not be accessible to non-medical staff but, on the contrary, should be kept under lock and key by the nurse or doctor. Moreover, all medical examinations should be conducted out of the hearing and – unless the doctor concerned requests otherwise in a particular case – out of the sight of custodial staff.