Construction Standards

(1) No boiler or unfired pressure vessel shall be installed for operation in the State unless it is designed, constructed, inspected, stamped, and installed for the desired pressure and temperature in accordance with the provisions of this Chapter, the applicable section of the ASME Code, and other applicable law. (2) Boilers and pressure vessels shall bear the NB stamping and the manufacturer’s NB number as registered with the NB. A copy of the Manufacturer’s Data Report signed by the manufacturer’s representative and the NB commissioned inspector employed by the third party inspection agency shall be filed with the Chief Inspector or Chief Inspector’s Designee when the boiler or pressure vessel is shipped into this State for installation. (3) Electrically heated boilers subject to the ASME Code requirements shall bear the “Underwriters Laboratory” label in addition to the required ASME Certification Mark and Certification Designator. This means that the boiler shall be supplied by the manufacturer as a complete unit and not converted in the field. (4) Piping. (a) Power piping external to power boilers from the boiler to the first stop valve of a single boiler, and to the second stop valve in a battery of two (2) or more boilers, is subject to BOILER INSPECTIONS CHAPTER 0800-03-03 the requirements of the ASME Code, Power Boilers, Section I. The design, fabrication, installation and testing of the valves and piping shall be in accordance with ASME 31.1. (b) Welded piping is subject to the ASME Code requirements for proper code certification, including stamping in conformance with the code and furnishing of applicable ASME data report forms for the owners and the Chief Inspector or Chief Inspector’s Designee. (5) Exemptions. Potable water heaters are exempt from the requirements of paragraphs (1) and (2) of this rule when neither of the following limitations are exceeded: (a) Heat input of 199,999 BTU/hr. (b) Water temperature of 210°F. However, such potable water heaters, including instantaneous water heaters, with a heat input of between 100,000 and 199,999 BTU/hr are subject to registration, inspection and inspection certificate requirements. (c) These vessels are required to have an NB rated, ASME constructed, test-lever pressure-temperature activated safety relief device. (6) “Tennessee Special” Boilers and Pressure Vessels. If a boiler or pressure vessel is of special design, or one that cannot bear the ASME and NB stamping, details of the proposed construction (including shop drawings) shall be submitted to the Chief Inspector or Chief Inspector’s Designee. Approval for construction and installation as a “Tennessee Special” boiler or pressure vessel must be obtained from the Board before construction is started. (7) Tennessee Standard Pressure Vessels. (a) Vessels constructed by an owner-user who is authorized by the State as an Owner- User Inspection Agency and who holds a valid Certificate of Authorization to use the ASME Certification Mark with Certification Designator shall be stamped “Tennessee Standard,” provided the vessels are: 1. Inspected by an owner-user inspector holding a valid certificate of competency issued by the State; and 2. To be used exclusively by the owner-user and not for resale. (b) Such vessels shall meet all requirements of the ASME Code, Section VIII, Division 1, except that they are inspected by an owner-user inspector.