A prison cell (also known as a jail cell) is a small room in a prison or police station where a prisoner is held. Cells greatly vary by their furnishings, hygienic services, and cleanliness, both across countries and based on the level of punishment to which the person being held has been sentenced. Cells can be occupied by one or multiple people depending on factors that include, but are not limited to, inmate population, facility size, resources, or inmate behavior. Description The International Committee of the Red Cross recommends that cells be at least in size for a single cell accommodation (one person in the cell). However, in shared or dormitory accommodations, it recommends a minimum of per person, including in cells where bunk beds are used. Prison cells vary in size internationally from in Guinea, in Poland, in Germany to in Norway and in Switzerland. Council of Europe (Strasbourg, 15 December 2015) call for a minimum standard for personal living space in prison establishments is 6m² of living space for a single-occupancy cell or of living space per prisoner in a multiple-occupancy cell for the prevention of torture and inhuman treatment. A March 1991 federal government study of U.S. prisons reported that: "Until recently, the Federal Bureau of Prisons based its determination of rated capacity in existing facilities on a single-bunking standard, which currently calls for providing each inmate with at least 35 square feet of unencumbered space in a single cell. This essentially translates to a cell size of roughly .* *(, minus of "unencumbered space" leaves of "encumbered" space, which would likely contain bed, toilet and sink - for a single inmate in a single cell) "In practice, however, BOP has accommodated inmate population increases by double-bunking inmates in virtually all its facilities and in cells... of varying sizes, but generally in the 50 to 70 square foot range." In the United States old prison cells are usually about in dimension which is , (moreover, however, American Correctional Association standards call for a minimum of , with steel or brick walls and one solid or barred door that locks from the outside. Many modern prison cells are pre-cast. Solid doors typically have a window that allows the prisoner to be observed from the outside. Furnishings and fixtures inside the cell are constructed so that they cannot be easily broken, and are anchored to the walls or floor.