The State Department of Correctional Services says 29 inmates recently tested positive for coronavirus in four different housing units at the facility in Lincoln.
Corrections Director Scott Frakes said the majority of cases are asymptomatic, with the isolation done out of an abundance of caution.
The quarantine will last for at least two weeks.
With the quarantine, Frakes said the inmate visitation program would remain closed across the agency.
“We had planned to discuss reopening of visits and volunteer programs this coming week. It is obvious we made the right decision to shut down those activities when we did. With the current situation at NSP, and seeing the elevated number of cases in both Lancaster and Douglas Counties, it is best to postpone reopening of those programs for now.”