(1) No person, other than an employee or contractor of the service, shall be required to perform labor which involves the essential operation and maintenance of a service site or the regular care, treatment or supervision of other persons; provided, however, that:

1. (a) Persons who reside at a residential site may be required to perform labor involving normal housekeeping and home maintenance functions;
2. (b) Persons may perform labor in accordance with a planned and supervised program of vocational and rehabilitation training as set forth in the person's individual service plans or individualized treatment plans.