All volunteer members in good standing in any fire company or hook and ladder company in this state shall be exempt from militia duty in time of peace; PROVIDED, that said certificate of exemption shall be approved and authorized by the council or board of trustees under the seal of the city or village in which the fire department issuing the same is located. When any member shall have retired from such company after having served ten years or more he shall be furnished a certificate of exemption. Any member in good standing in any fire company or hook and ladder company in this state on September 20, 1957, shall be furnished a certificate of exemption after five years of service; PROVIDED, when a member serves in different fire companies or hook and ladder companies in this state, or at different times in the same company, he may add the years he previously served to his present membership in order to qualify for such exemption. Persons who received certificates of exemption for five years' service prior to September 20, 1957, shall be entitled to all exemptions theretofore enjoyed by holders of such certificates.