A special housing unit (SHU) is a high security area within a prison used for prisoners who may pose a danger to others or be at risk if left in the general population. Conditions inside the unit can vary, depending on the prison and its policies. Prisoners usually spend most of their time in their cells, with limited opportunities for recreation, and their contact with other prisoners and the outside world may be limited. In slang terms, this area of a prison is sometimes referred to as “the hole” by prisoners and guards.
Some special housing units have one and two person cells while others only offer solitary cells. The amenities are usually very basic, and prisoners may not be allowed to have electronics and certain other possessions permitted to the general population. Sometimes, the unit is used primarily for disciplinary purposes. Prisoners in the unit for disciplinary reasons will remain in solitary confinement and isolation; soundproofing and other tactics are used to limit communication between cells.
There are several reasons why a prisoner may end up in this area. New prisoners often go here first to give prison officials time to determine how they will respond to imprisonment so they can be assigned to an appropriate unit. Prisoners can be sent back to the special housing unit for disciplinary infractions or when other prisoners threaten them, indicating the need to isolate them for safety. Prison personnel may have considerable leeway in making decisions about prisoner movements and transfers, particularly in a crisis where rapid response is necessary.
Within the unit, prisoners stay in their cells. Mail and meals are delivered directly to them. If a prisoner needs medical attention, doctors and nurses travel to the prisoner's cell for basic evaluations and treatment. The prison may authorize a transfer in the event of a more complex medical issue. Prisoners are typically under surveillance using cameras and visual checks to identify any safety concerns, and they receive an hour of recreation a day in a controlled area.
The practice of isolation in prison settings is controversial in some parts of the world. Mental health professionals believe that conditions in a special housing unit can increase the risks of developing mental illness. Prisoners often have trouble adjusting and may experience stress and disorientation. Welfare organizations recommend shifting away from this model for isolating prisoners and developing more humane measures for addressing disciplinary concerns or prisoner safety issues.