OAC Rule 6. Service of Documents. 

A.  Service of pleadings or other papers on a party may be made by hand delivery, by mail to the address given in the pleadings, by facsimile transmission to a facsimile number given in the pleadings, by e-mail to an e-mail address given in the pleadings, or to the party's last known address as provided to the OAC.  When an attorney represents a party, service shall be made on the attorney.

B.  Attorneys and parties not represented by attorneys shall inform the OAC and all other parties of their current addresses and telephone numbers, and their facsimile numbers and e-mail addresses if they have such capability, and of any change of addresses during the course of the proceedings.