A/66/268 confinement is a regular feature of pretrial detention (A/63/175, para. 78 (i)). The purposes for the use of solitary confinement in pre-charge and pretrial detention vary widely, and include preventing the intermingling of detainees to avoid demoralization and collusion, and to apply pressure on detainees to elicit cooperation or extract a confession. 26 F. Conditions of solitary confinement 46. The administration of prisons and the conditions in which prisoners are held is governed by prison regulations and national laws, as well as by international human rights law. Fundamental norms that are binding by virtue of being treaty-based or part of customary international law are supplemented and interpreted through the United Nations Standard Minimum Rules for the Treatment of Prisoners, adopted by the Economic and Social Council in 1957. Although not directly binding, the Standard Minimum Rules are widely accepted as the universal norm for the humane treatment of prisoners. 47. The particular conditions in which detainees are held in solitary confinement vary between institutions and jurisdictions. Most, however, have a number of physical and non-physical conditions (or a prison regime) in common. 1. Physical conditions 48. The principal physical conditions relevant to solitary confinement are cell size, presence of windows and light, and access to sanitary fixtures for personal hygiene. In practice, solitary confinement cells typically share some common features, including: location in a separate or remote part of the prison; small, or partially covered windows; sealed air quality; stark appearance and dull colours; toughened cardboard or other tamperproof furniture bolted to the floor; and small and barren exercise cages or yards (E/CN.4/2006/6/Add.3, para. 47). In some jurisdictions, prisoners in solitary confinement are held in leg irons and subjected to other physical restraints (A/HRC/13/39/Add.4, para. 76 (f)). 49. There is no universal instrument that specifies a minimum acceptable cell size, although domestic and regional jurisdictions have sometimes ruled on the matter. According to the European Court of Human Rights in Ramírez Sanchez v. France, a cell measuring 6.84 square metres is “large enough” for single occupancy. 27 The Court did not elaborate on why such measures could be considered adequate; the Special Rapporteur respectfully begs to differ, especially if the single cell should also contain, at a minimum, toilet and washing facilities, bedding and a desk. 50. The presence of windows and light is also of critical importance to the adequate treatment of detainees in solitary confinement. Under rule 11 of the Standard Minimum Rules for the Treatment of Prisoners, there should be sufficient light to enable the detainee to work or read, and windows so constructed as to allow airflow whether or not artificial ventilation is provided. However, State practice reveals that this standard is often not met. For example, in Georgia, window- __________________ 26 27 14 Peter Scharff Smith, “Solitary Confinement: An introduction to the Istanbul Statement on the Use and Effects of Solitary Confinement”, p. 41. Ramírez Sanchez v. France, Application No. 59450/00, European Court of Human Rights, para. 102 (2006). 11-44570