(a) The institutional division may not house more than two inmates in a cell designed for occupancy by one inmate or two inmates.
(b) The institutional division shall house the following classes of inmates in single occupancy cells:
(1) inmates confined in death row segregation;
(2) inmates confined in administrative segregation;
(3) inmates assessed as having intellectual disabilities and whose habilitation plans recommend housing in a single occupancy cell;
(4) inmates with a diagnosed psychiatric illness being treated on an inpatient or outpatient basis whose individual treatment plans recommend housing in single occupancy cells; and
(5) inmates whose medical treatment plans recommend housing in a single occupancy cell.