imposition of disciplinary sanctions or other restrictive measures. However, they have to visit those held in involuntary separation daily to assess the impact of segregation on prisoners’ physical and mental health, including indications of suicidal tendencies or self250 harm, and also to detect any signs of torture or other ill-treatment. Solitary confinement is absolutely prohibited if indefinite or prolonged, defined as 15 251 days or more, as this amounts to ill-treatment or even torture. It is also prohibited for prisoners with mental or physical disabilities when their condition would be exacerbated, 252 for children, for pregnant women, for women with infants and for breastfeeding women in 253 detention. Disciplinary sanctions or restrictive measures, including solitary confinement, 254 should not include the prohibition of family contact. Solitary confinement represents a high-risk situation for human rights abuses, where torture and other ill-treatment may go unnoticed and undetected, and has been found to have significant adverse effects on the mental and physical health and well-being of 255 prisoners. According to the UN Special Rapporteur on Torture, solitary confinement amounts to torture or other ill-treatment “where the physical conditions of solitary confinement are so poor and the regime so strict that they lead to severe mental and 256 physical pain or suffering of individuals who are subjected to [it]”. The confinement conditions for detainees held separately in high-security or special units/prisons will in many cases constitute solitary confinement, or even indefinite and prolonged solitary confinement. In some OSCE participating States, (suspected) violent extremist prisoners are held in solitary confinement for an indefinite period of time, without 257 regular reviews or reasons given for its prolongation. This constitutes indefinite solitary 258 confinement, as the prisoner does not know when it will end. 250 UN Nelson Mandela Rules, op. cit., note 13, Rule 46; EPR, op. cit., note 123, Rule 43.2-43.3.; ODIHR & PRI, Guidance Document on the Nelson Mandela Rules, ibid., Chapter 4, para. 75. 251 According to Mandela Rule 44, “Prolonged solitary confinement shall refer to solitary confinement for a time period in excess of 15 consecutive days.” This prohibition extends to repetitive periods of isolation imposed in close succession. 252 UN Havana Rules, op. cit., note 86, Rule 67; UN Nelson Mandela Rules, op. cit., note 13, Rule 45.2. 253 UN Bangkok Rules, op. cit., note 79, Rule 22; UN Nelson Mandela Rules, ibid., Rule 45.2. See also, UN Special Rapporteur on Torture, “Interim Report”, A/66/268, 5 August 2011, para. 86; International Psychological Trauma Symposium, Istanbul, “Istanbul Statement on the Use and Effects of Solitary Confinement”, 9 December 2007. 254 UN Nelson Mandela Rules, ibid., Rule 43.3; UN Bangkok Rules, ibid., Rule 23. 255 PRI and the APT, “Balancing Security and Dignity in Prisons: A Framework for Preventive Monitoring”, op. cit., note 135, p. 14. 256 UN Special Rapporteur on Torture, op. cit., note 253, para. 74; Report of the UN Special Rapporteur on Torture, A/68/295, 9 August 2013, para. 60, “Prison regimes of solitary confinement often cause mental and physical suffering or humiliation that amounts to cruel, inhuman or degrading treatment or punishment. If used intentionally for purposes such as punishment, intimidation, coercion or obtaining information or a confession, or for any reason based on discrimination, and if the resulting pain or suffering are severe, solitary confinement even amounts to torture.” 257 Failure of a state to periodically review a prisoner’s solitary confinement and give reasons for any decision to continue it could result in a violation of Article 3 ECHR: “Keeping detainees in isolation, without sufficient mental and physical stimulation, and without examining if there were concrete reasons for the prolonged application of that regime, was not necessary in order to ensure safety in prison.” Violations have also been found for conditions of detention in solitary confinement and the regime for prolonged periods. See: Öcalan vs Turkey, or Karwowski vs. Poland. 258 ODIHR & PRI, Guidance Document on the Nelson Mandela Rules, op. cit., note 10, Chapter 4, paras. 54-55. See also: ECtHR jurisprudence on solitary confinement and violations of Article 3, prohibition of inhuman or degrading treatment. 57