Any placement of a child by a local education department or by a social services department in a residential school should be preceded by: (a) consultation between the departments as to whether an assessment by an appropriate social worker of the child's needs and family situation is needed as well as an educational assessment; and (b) in the light of (a) and any subsequent assessment, a decision about the need for (and extent of) any further involvement of the social services department with the child to ensure continuity of planning for the child's long term welfare and protection of the child's rights.