A decision must be rendered within 20 days after the date the hearing is concluded.  [56 O.S. § 237.8]  In the event the record is left open by order of the administrative law judge (ALJ) after a hearing is concluded, a decision must be rendered 20 days after the last evidence, brief, or memorandum of law is received into the record or the ALJ determines that the record is closed.  If the decision is not rendered within this time, the chief ALJ may be advised by either party so that appropriate measures may be taken by the chief ALJ.