The board of education or board of health providing a system of medical and dental inspection of school children, as authorized by section 3313.68 of the Revised Code, shall include in such inspection tests to determine the existence of hearing and visual defects in school children. The methods of making such tests and the testing devices to be used shall be such as are approved by the department of health.

Any child shall be exempted from a dental inspection if he has been examined for dental defects by a regularly licensed dentist, from a hearing test if he has been examined by a regularly licensed physician, and from a visual test if he has been examined by a regularly licensed physician or optometrist upon presentation to the school authorities of a certificate to the effect that he has been so examined during the twelve months immediately preceding the date of such inspections.