Oregon Revised Statutes Utility Regulation § 756.558

(1) At the conclusion of the taking of evidence, the Public Utility Commission shall declare the taking of evidence concluded. Thereafter no additional evidence shall be received except upon the order of the commission and a reasonable opportunity of the parties to examine any witnesses with reference to the additional evidence and otherwise rebut and meet such additional evidence.

(2) After the completion of the taking of evidence, and within a reasonable time, the commission shall prepare and enter findings of fact and conclusions of law upon the evidence received in the matter and shall make and enter the order of the commission thereon. The findings of fact and conclusions of law may be embodied in the same instrument with the order or may be embodied in a separate instrument. The findings of fact, conclusions of law and order thereon shall be signed by the commission. The order shall state the date it becomes effective. A copy of the findings of fact and conclusions of law and a copy of the order shall, forthwith upon the entry of the same, be served upon each of the parties to the proceeding.

(3) Upon application of any person, the commission shall furnish certified copies, under the seal of any order made by the commission.