The Intensive Management Unit, or IMU, was the last major piece in the puzzle for regaining control of the penitentiary. Finally, segregation was moved out of the middle of the institution and inmates in seg were truly isolated from the rest of the prison population. The IMU was officially opened on June 27, 1984.
The design and operating procedures for the IMU were based on one simple principle: that no one – inmate or staff – ever gets hurt. For the most part, it’s worked that way.