{"data":{"id":"us-ok/okla.-stat.-tit.-40-40-141.2","jurisdiction":"us-ok","citation":"Okla. Stat. tit. 40, § 40-141.2","heading":"Exemptions – Exhibitor boilers","body":"A. This act shall not apply to the following boilers, hot water\n\nheaters and pressure vessels:\n\n1. Pressure vessels used for the transportation of compressed\n\ngases if constructed and operated in compliance with specifications\n\nand regulations of the United States Department of Transportation or\n\nof the Corporation Commission of Oklahoma and any unfired pressure\n\nvessels used as containers for liquefied petroleum gases and subject\n\nto the jurisdiction of the United States Department of\n\nTransportation or the Oklahoma Liquefied Petroleum Gas\n\nAdministration or successor agencies;\n\n2. Pressure vessels containing air located on vehicles\n\noperating pursuant to regulations of other jurisdiction authorities;\n\n3. Pressure vessels having an internal or external operating\n\npressure not exceeding fifteen (15) pounds per square inch gauge -\n\none hundred three (103) kilopascals gauge with no limit on size;\n\n4. Pressure vessels having an inside diameter not exceeding six\n\n(6) inches (152mm) with no limitation on pressure;\n\n5. Pressure vessels with a nominal water containing capacity of\n\none hundred twenty (120) gallons or four hundred fifty (450) liters\n\nor less, to be used for domestic supply purposes, for containing\n\nwater under pressure including those containing air, the compression\n\nof which serves only as a cushion;\n\n6. Pressure vessels containing water heated by steam or other\n\nindirect means when none of the following limitations is exceeded:\n\na. a heat input of two hundred thousand (200,000)\n\nBritish thermal units per hour - fifty-eight thousand\n\nsix hundred (58,600) watts,\n\nb. a water temperature of two hundred ten degrees\n\nFahrenheit (210º F), or\n\nc. a water containing capacity of one hundred twenty\n\n(120) gallons - four hundred fifty (450) liters;\n\n7. Pressure vessels which may be classified as pressure\n\ncontainers which are integral parts of components of rotating or\n\nreciprocating mechanical devices such as pumps, compressors,\n\nturbines, generators, engines and hydraulic or pneumatic cylinders\n\nwhere the primary design considerations and/or stresses are derived\n\nfrom the functional requirements of the device, or structures whose\n\nprimary function is the transport of fluids from one location to\n\nanother within a system of which it is an integral part, i.e.,\n\npiping systems;\n\n8. Hot water supply boilers which are directly fired with oil,\n\ngas or electricity when none of the following limitations are\n\nexceeded:\n\na. a heat input of two hundred thousand (200,000)\n\nBritish thermal units per hour - fifty-eight thousand\n\nsix hundred (58,600) watts,\n\nb. a water temperature of two hundred ten degrees\n\nFahrenheit (210º F), or\n\nc. a water containing capacity of one hundred twenty\n\n(120) gallons - four hundred fifty (450) liters;\n\n9. Boilers and pressure vessels under federal control and\n\nrailroad locomotive boilers;\n\n10. Pressure vessels located on remote sites and limited to\n\noil and natural gas gathering facilities or processing plants that\n\nhave fewer than ten buildings intended for human occupancy per one-\n\nfourth (1/4) square mile and where the closest building is at least\n\ntwo hundred twenty (220) yards from any vessel;\n\n11. Pressure vessels in the care, custody and control of\n\nresearch facilities and used solely for research purposes which\n\nrequire one or more details of noncode construction or which involve\n\ndestruction or reduced life expectancy of those vessels; and\n\n12. Hot water supply heaters as defined in subparagraph f of\n\nparagraph 1 of Section 141.1 of this title, with piping connections\n\nto the potable water supply system which are intended to supply hot\n\nwater for domestic or commercial purposes other than space heating.\n\nHowever, the Commissioner shall make routine inspections and issue\n\nnecessary orders regarding existing hot water supply heaters located\n\nin facilities or installations owned or operated by the State of\n1 of Section 141.1 of this title, with piping connections\n\nto the potable water supply system which are intended to supply hot\n\nwater for domestic or commercial purposes other than space heating.\n\nHowever, the Commissioner shall make routine inspections and issue\n\nnecessary orders regarding existing hot water supply heaters located\n\nin facilities or installations owned or operated by the State of\n\nOklahoma or its agencies, counties, municipalities or school\n\ndistricts.\n\nB. The following boilers and pressure vessels shall be exempt\n\nfrom Sections 141.13 through 141.16 of this title:\n\n1. Pressure vessels not exceeding fifteen (15) cubic feet in\n\nvolume and two hundred fifty (250) pounds per square inch gauge\n\npressure;\n\n2. Low pressure steam boilers, hot water heating boilers, hot\n\nwater supply boilers, hot water supply heaters or pressure vessels\n\nwhich are located in private residences or in apartment houses of\n\nless than six-family units; and\n\n3. Pressure vessels operated entirely full of water or other\n\nliquid which is not materially more hazardous than water, provided\n\nthe temperature of the vessel contents does not exceed one hundred\n\nfifty degrees Fahrenheit (150º F) or a pressure of two hundred (200)\n\npounds per square inch gauge.\n\nC. 1. Either a special inspector or an inspector licensed by\n\nthe Department of Labor shall inspect exhibitor boilers on an annual\n\nbasis when exhibitor boilers are being operated at public events.\n\nExhibitor boilers maintained by owner/operators for private use and\n\nnot for operation for the public shall be exempt from inspection by\n\nthis state. Annual inspections by this state or a special inspector\n\nshall consist of the following:\n\na. an internal and external visual,\n\nb. threaded openings in the boiler may be inspected, when\n\ndeemed appropriate, by the inspector after conducting\n\nan internal and external visual,\n\nc. a hydrostatic pressure test at one and twenty-five\n\none-hundredths (1.25) times the maximum allowable\n\nworking pressure,\n\nd. the maximum allowable working pressure shall not\n\nexceed one hundred eighty-five (185) pounds per square\n\ninch (psi),\n\ne. the ash pan and grates on a dry bottom vessel shall be\n\nremoved to allow a visual inspection of the crown\n\nsheet,\n\nf. a visual inspection of the crown sheet on wet bottom\n\nboilers,\n\ng. all boilers shall have a fusible plug that is\n\nconstructed to the American Society of Mechanical\n\nEngineers (ASME) code and indicated by an ASME marking\n\non the filler material. It shall protrude one (1)\n\ninch into the water on a fireside fusible plug and no\n\nmore than one (1) inch on a waterside fusible plug,\n\nh. the pressure relief valve shall be National Board\n\ncapacity certified,\n\ni. a gage glass shall be present with a guard to protect\n\nthe glass, drain valve or petcock, be piped to a safe\n\nlocation, and be operational,\n\nj. try cocks shall be located in correlation to the\n\nminimum required water level,\n\nk. a pressure gage that has been tested and proven\n\naccurate at the time of the annual pressure test,\n\nl. all piping shall be schedule 80, black pipe (SA-53 B\n\nor SA-105 B) from the boiler to the first valve,\n\nm. the boiler shall be equipped with two means of\n\nsupplying feed water while under pressure, and\n\nn. all welding to the boiler shall be done by a certified\n\nrepair organization as accredited and described in\n\nPart RA of the National Boiler Inspection Code (NBIC).\n\n2. Exhibitor boilers shall have a nondestructive exam performed\n\nonce every five (5) years for determining repairs and thin areas\n\nthat need to be repaired. An inspector from the Department of Labor\n\nmay perform a random nondestructive exam annually. Results from the\n\nexam may be used by the inspector to waive any time remaining on the\n\nfive-year period. A nondestructive exam shall meet the following\n\nrequirements:\n\na. on a dry bottom boiler, no less than 150 readings\n\nshall be taken,\ns for determining repairs and thin areas\n\nthat need to be repaired. An inspector from the Department of Labor\n\nmay perform a random nondestructive exam annually. Results from the\n\nexam may be used by the inspector to waive any time remaining on the\n\nfive-year period. A nondestructive exam shall meet the following\n\nrequirements:\n\na. on a dry bottom boiler, no less than 150 readings\n\nshall be taken,\n\nb. on a wet bottom boiler, no less than 180 readings\n\nshall be taken,\n\nc. this exam shall include the areas surrounding the\n\ncrown sheet stays and any areas subject to corrosion,\n\nd. a loss of metal that is greater than forty percent\n\n(40%) of the original boiler plate thickness in an\n\narea greater than three (3) inches in diameter shall\n\nbe considered to be a thin area and shall need to be\n\nrepaired prior to any operation,\n\ne. exams shall be by a certified professional pursuant to\n\napplicable provisions of law of this state,\n\nf. no exam shall be by a certified professional that has\n\na vested interest in the boiler that is being\n\nexamined,\n\ng. the exam results shall be made available to the\n\norganization where the boiler is being exhibited, if\n\nrequested, and\n\nh. the exam results shall be made available at the time\n\nof the annual inspection to the inspector, if\n\nrequested.\n\nFor purposes of this subsection, \"exhibitor boiler\" shall mean a\n\nboiler which is operated in this state for nonprofit purposes\n\nincluding, but not limited to, exhibitions, fairs, parades, farm\n\nmachinery shows, or any other event of a historical or educational\n\nnature. An exhibitor boiler includes steam locomotives, traction\n\nand portable steam engines, and stationary boilers of the firetube,\n\nwatertube, model or miniature, and may be riveted, riveted and\n\nwelded, or all welded construction, if used within the state for\n\nnonprofit purposes.\n\nD. Pressure vessels, associated piping, and connections\n\nlocated on oil and gas lease sites shall fall under the exclusive\n\njurisdiction of the Corporation Commission. The Corporation\n\nCommission shall be responsible for the inspection of oil and gas\n\nlease pressure vessels to ensure the vessels, associated piping, and\n\nconnections are properly operated and maintained in a manner deemed\n\nappropriate by the Corporation Commission.","path":["OK Code","Title 40"],"source_url":"https://www.oklegislature.gov/OK_Statutes/CompleteTitles/os40.pdf","current_through":"2026-08-14","vintage":"open-us-law v2026.08, retrieved 2026-09-14","retrieved_at":"2026-09-14T18:32:36Z","sha256":"a387bd9070b0e93eabc7e3adc35ff9cd334b306a24acdb7087f739a1408baac6","source_id":"us-ok","stale":false,"prev":"us-ok/okla.-stat.-tit.-40-40-141.19a","next":"us-ok/okla.-stat.-tit.-40-40-141.20"},"notice":"GroundRules: Original legal text. Not legal advice."}