The qualifications for certification of a candidate for the office of electrical inspector shall be as follows: The candidate shall be a citizen of the Commonwealth of Pennsylvania, shall be between the ages of thirty and fifty-five years, of temperate habits, of good repute as a man of personal integrity, in good physical condition, shall have had five years' experience in gassy mines of this Commonwealth as a mine electrician or an electrical engineer, and shall have successfully passed the examination for electrical inspectors provided in section 109 of this article:¹ Provided, however, That any candidate who has honorably served in the armed forces of the United States or an ally thereof shall be eligible to take such examination, where the required continuity of practical experience has been interrupted by such military service.