The showers are a location in prisons in The Escapists and The Escapists 2. Showers are located in a dedicated section as part of the prison. Showers are usually open throughout the day but they often lock at Lights out until morning.
Every prison has a shower period as part of the daily Routines usually lasting one in-game hour that requires you to attend. Absence from shower period will result in a large increase in your heat. All inmates will go to shower during shower period and use one of the shower spots until the next routine of the day starts. Also, three guards will attend and supervise shower period, the same three guards that attend Roll call. Since all of the inmates are in one spot at this time, it is a good time to give items or complete favors. Some prisons have a scanner at the entrance, so be careful when entering or exiting the shower room and remove all Contraband items or carry a Contraband Pouch.
To use the showers, simply walk on a tile that has the shower spray on you (The Escapists 1) or interact with the shower head (The Escapists 2). Using the shower will restore your stamina/fatigue until you move away from the shower spot. Shower spots can sometimes be tricky to find as not all floor tiles in a shower block have a shower spray. They are usually adjacent to walls and rarely in the middle of the floor space. You can use the showers any time during the day to restore stamina/fatigue, and even at night during an escape! (note that many prisons lock the shower room door at Lights out, usually with a Cell Key).