An elevator or accessibility lift mechanic shall pass an examination given by the commissioner provided the person either (a) has at least 2 years of documented experience, with an average of 1,800 hours in each year over the 2-year period, working in this state directly under a licensed New Hampshire elevator or accessibility lift mechanic; or (b) holds a certificate or license of competency as an elevator or accessibility lift mechanic issued by another state and has proven to the satisfaction of the commissioner that the person has experience as an elevator or accessibility lift mechanic for at least 3 consecutive years, with an average of 1,800 hours in each year over the 3-year period. A license shall be issued to the mechanic for a 2-year period. A fee of $50 shall be charged for the initial examination and license. A license may be renewed every 2 years upon payment of a fee of $35. Employees of the department of labor shall not be charged for the issuance or renewal of a license. A person who holds a certificate or license of competency as a mechanic issued by another state may be issued a license without examination upon payment of a fee of $35, provided that licensees of New Hampshire are not subject to greater requirements for certification or licensure in the other state than those required by New Hampshire. The commissioner may revoke any license for cause shown, after a hearing. The holder of a license under question shall receive 7 days’ written notice informing the licensee of the charges and of the time and place of the hearing.