Former employees of Aurora Las Encinas Hospital, a private psychiatric facility in Pasadena, filed a class-action lawsuit Thursday against the owner alleging that chronic under staffing has compromised patient care.

The lawsuit, filed in Los Angeles County Superior Court on behalf of four former employees, says under staffing forced Las Encinas staff to work past the ends of their shifts, with no overtime pay, to complete work obligations. In addition to complaints about staffing levels, the suit alleges unsanitary conditions for employees.

The employees also alleged that the hospital told its workers not to spend time studying for mandatory examinations, in order to avoid having to pay workers for that time.

Instead, the answers were provided with the exam, the suit alleges.

The lawsuit seeks class action status for three psychiatric hospitals in Southern California run by Signature Healthcare Services