TN Code § 68-122-110 (2021)
2021 Tennessee Code|Title 68 - Health, Safety and Environmental Protection|Chapter 122 - Boiler Inspection, Erectors and Repairers|Part 1 - General Provisions|§ 68-122-110. Inspection of Boilers

  Each boiler used or proposed to be used within this state, except boilers exempt in § 68-122-105, shall be thoroughly inspected as to their construction, installation, condition and operation as follows:  Power boilers shall be inspected annually both internally and externally while not under pressure, and shall also, if possible, be inspected externally while under pressure approximately six (6) months following the date of each internal inspection;   Low pressure heating boilers shall be inspected both internally and externally biennially where construction will permit;   Unfired pressure vessels subject to internal corrosion shall be inspected both internally and externally biennially where construction will permit, except that the board may, in its discretion, provide for longer periods between inspections; and   Unfired pressure vessels not subject to internal corrosion shall be inspected externally at intervals set by the board, but internal inspections shall not be required of unfired pressure vessels, the contents of which are known to be noncorrosive to the material of which the shell, head, or fittings are constructed, either from the chemical composition of the contents or from evidence that the contents are adequately treated with a corrosion inhibitor; provided, that such vessels are constructed in accordance with the rules and regulations of the board or in accordance with standards equivalent to the rules and regulations of the board in effect at the time of manufacture.     A grace period of two (2) months longer than the twelve-month period may elapse between internal inspections of a boiler while not under pressure or between external inspections of a boiler while under pressure.   The inspections required in this section shall be made by the chief inspector, or by a deputy inspector, or by a special inspector provided for in this part.   If at any time a hydrostatic test shall be deemed necessary, it shall be made, at the discretion of the inspector, by the owner or user of the boiler.   All boilers to be installed in this state after the twelve-month period from the date upon which the rules and regulations of the board shall become effective shall be inspected during construction as required by the applicable rules and regulations of the board by an inspector authorized to inspect boilers in this state, or, if constructed outside of the state, by an inspector holding a certificate from the national board of boiler and pressure vessel inspectors, or a certificate of competency as an inspector of boilers for a state that has a standard of examination substantially equal to that of this state as provided in § 68-122-109.    Notwithstanding subsection (a), the board may, in its discretion, grant a variance for longer intervals between inspections. All requests for boiler inspection variances shall be submitted to the chief inspector or the chief inspector's designee no less than forty-five (45) days prior to the next regularly scheduled or called meeting of the board.   The board shall produce a guide and checklist setting forth conditions which must be met before a variance for longer intervals between inspections may be granted.   All boilers operating under a variance pursuant to this subsection (f) shall be inspected externally while under pressure approximately every six (6) months for the duration of the variance.   Any boiler that fails an external inspection pursuant to subdivision (f)(3), shall be shut down and inspected internally, and the variance shall be rescinded.     The board may also, in its discretion, grant other variances where the board deems it necessary in order to protect the health, safety and welfare of the public. All requests for variances shall be submitted to the chief inspector or the chief inspector's designee no less than forty-five (45) days prior to the next regularly scheduled or called meeting of the board.