Rectification of record errors: authorities may correct apparent errors within a limited period, except clerical slips; natural justice applies. An authority that issued any decision, order, notice, certificate or other document may rectify an error apparent on the face of the record on its own motion or when notified by an officer or the affected person; rectifications are subject to prescribed time limits, except that clerical or arithmetical errors from accidental slips or omissions are not bound by the outer time limit, and any rectification adversely affecting a person requires observance of natural justice.