1 Lockdown

"23/1" is prison shorthand for a restrictive housing schedule: an incarcerated person spends 23 hours a day locked in a cell and gets 1 hour out, typically for recreation, a shower, or a phone call. It describes the daily structure of solitary confinement and similar restrictive-housing statuses, not a specific unit name or legal term found in statute.

The number can shift with facility conditions. A related shorthand, "22/2," describes 22 hours locked in with 2 hours out; both describe the same category of restrictive confinement, and international human rights standards use the same threshold to define it.

Where the Term Comes From

"23/1" is not Bureau of Prisons terminology; the BOP's own policy documents use terms like Special Housing Unit (SHU), Special Management Unit (SMU), and Administrative Detention. "23/1" is the plain-language description incarcerated people, their families, and advocates use to describe what that custody actually looks like day to day, and it has become the common shorthand across podcasts, forums, and reentry content that cover federal and state prison life.

The United Nations' Nelson Mandela Rules, the internationally recognized standard for humane treatment of prisoners, define solitary confinement using the same threshold: "confinement of prisoners for 22 hours or more a day without meaningful human contact." A 23/1 schedule sits squarely inside that definition.

What the Hour Out Actually Involves

The single hour out of a cell under a 23/1 schedule is typically used for one or a combination of: recreation in a small enclosed yard or cage, a shower, a phone call, or legal/law-library access. It is not free movement around the facility, and it can be further restricted for disciplinary or staffing reasons.

Federal oversight bodies have documented that Special Housing Units routinely fall into the 23/1 pattern. A 2024 U.S. Government Accountability Office report found the Bureau of Prisons continues to house a substantial number of federal inmates in Special Housing Units where individuals are isolated for up to 23 hours a day. A 2014 BOP-commissioned review recommended a minimum of ten hours a week of structured out-of-cell therapeutic activity plus ten additional hours of unstructured out-of-cell time for people held in restrictive housing, a benchmark well above what a strict 23/1 schedule provides.

When a 23/1 Schedule Applies

A 23/1 or similar restrictive schedule can apply for several distinct reasons, and the label alone doesn't tell you which:

• Disciplinary segregation: placement following a rule violation, for a fixed period set by the facility's disciplinary process.
• Administrative detention: placement pending investigation, pending transfer, or for the incarcerated person's own protection, not necessarily tied to any finding of wrongdoing.
• Facility-wide lockdown: a temporary, all-population restriction following a security incident, staffing shortage, or emergency, which can put an entire unit or institution on a 23/1-style schedule regardless of any individual's status.
• Special Management Unit or high-security housing: longer-term restrictive placement tied to gang validation, escape risk, or a record of violence inside the system.

Health and Policy Concerns

Extended time on a 23/1 schedule, especially for weeks or months, is the subject of extensive documented concern from medical and human-rights researchers over its psychological effects. The Nelson Mandela Rules go further than describing the daily hours: they cap "prolonged solitary confinement" at more than 15 consecutive days and classify anything beyond that as a practice that should be prohibited outright. The Vera Institute of Justice, a nonprofit criminal justice research organization, has documented that lockdown and restrictive-housing practices matching the 23/1 pattern remain widespread in U.S. prisons despite that international standard.

Frequently Asked Questions

Q: What does 23/1 mean in prison?

"23/1" describes a daily schedule where an incarcerated person is locked in their cell for 23 hours and let out for 1 hour, typically for recreation, a shower, or a phone call. It's the common shorthand for solitary confinement and similar restrictive-housing statuses, not an official Bureau of Prisons term.

Q: Is 23/1 the same as solitary confinement?

It describes the same daily structure. The United Nations' Nelson Mandela Rules define solitary confinement as confinement for 22 hours or more a day without meaningful human contact, which a 23/1 schedule meets. The Bureau of Prisons calls the housing categories that produce this schedule Special Housing Units (SHU) or Special Management Units (SMU) rather than using the term "23/1" itself.

Q: What do inmates do during the 1 hour out of their cell?

The hour typically covers one or a combination of recreation in a small enclosed yard, a shower, a phone call, or law-library access. It is not unrestricted movement around the facility, and it can be shortened or cancelled for disciplinary or staffing reasons.

Q: How long can someone be held on a 23/1 schedule?

It varies. Disciplinary segregation typically runs for a set period tied to the violation. Administrative detention can last as long as an investigation or pending transfer takes. A 2024 GAO report found the Bureau of Prisons continues to hold a substantial number of federal inmates in this kind of housing, and international standards classify anything beyond 15 consecutive days as prolonged solitary confinement that should not occur.

Q: Why do some prisons put an entire unit on 23/1 lockdown?

Facility-wide lockdowns, which can impose a 23/1-style schedule on an entire unit or institution regardless of individual status, are typically ordered after a security incident, a violent event, a staffing shortage, or another emergency. They are temporary by design, though advocacy groups have documented cases where they extend well beyond the initial emergency.

See also

• Residential Drug Abuse Program (RDAP)
• Ian Bick
• First Step Act: Overview and Implementation
• Prison Consultants