Tenn. Code § 68-122-204
An application for license under this part shall be made to the chief inspector of steam boilers and unfired pressure vessels, and the applicant shall pass an examination as prescribed by the board of boiler rules and given by the chief inspector, and further, the applicant must meet and continue to comply with the minimum qualifications as set up by the board of boiler rules and the recommended rules for repairs promulgated by the National Board of Boiler and Pressure Vessel Inspectors. Thereafter, at the earliest meeting of the board of boiler rules, the application shall be submitted to the board for its approval along with the recommendation of the chief inspector, and upon the finding of the board of boiler rules that the applicant has satisfied the requirements of this part, the chief inspector shall be authorized to issue a license to the applicant.
T.C.A. § 68-122-204