Any candidate may appeal to the Department to have examination papers reviewed on the ground of errors committed in the rating, if such appeal is made in writing within 30 days after the notice of the result of written examination has been mailed to the candidate. Upon a review of the candidate's examination papers, the rating may be changed in accordance with such review. When such review discloses errors which affect the examination papers of all candidates, then all the examination papers shall be reviewed. Except for protested items, examination material shall not be made available for review by candidates. Any candidate may appeal to the Department to have the decision of the oral examining board reviewed if such appeal is made in writing within 30 days after the notice of the result of the oral examination has been mailed to the candidate.