(a) Each residential treatment facility shall maintain written admission, continued stay and discharge criteria which are subject to the approval of the Office of Mental Health.

(b) The admission criteria must, at a minimum, provide that the child meets medical necessity criteria for access to residential treatment facility services pursuant with section 584.22(b) of this Part.

(c) Any additional admission criteria must relate to observable characteristics of the child. Such criteria may include age and gender.

(d) The continued stay criteria must, at a minimum, provide that the child meets medical necessity criteria for access to residential treatment facility services, and does not meet the residential treatment facility’s discharge criteria.

(e) The discharge criteria must at a minimum provide that the child has been evaluated and determined to no longer meet medical necessity criteria pursuant to section 584.22(b) of this Part. Age in and of itself is not an appropriate basis for discharge from a residential treatment facility, except that no resident may remain in a residential treatment facility after attaining the age of 22.