Author Topic: US State Boiler Code  (Read 7415 times)

Offline Dan Rowe

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US State Boiler Code
« on: April 17, 2019, 05:42:51 PM »
This thread is my attempt to find rules for US State model or small hobby boiler code or construction rules. These are not easy to find. Please check your state and see if the link is correct or if an exemption has been found. Please post any new information so this first post can be updated.

As far as I know the only countries to have a Model Boiler Code is the UK and Australia. I actually hope that some one can prove that statement wrong.

In the United States where I live the regulation of most types of boilers is at the State level. This means that there are 51 codes one for each State and one for the US Capitol. After finding NB-370 linked below I found a few other US cities with a boiler code including Buffalo NY, Chicago IL, Detroit MI, Los Angeles CA, Miami FL, Milwaukee WI, New Orleans LA, New York NY, Omaha NE, Seattle, WA, Spokane WA, Saint Louis MO, and Washington DC, Two states do not have a boiler code Idaho and Wyoming, So the total number of US State and city boiler codes is 61.

I keep a list of State boiler codes that I have found on the web. This stuff keeps moving around and changing so links go dead very frequently.

A few hints on reading one of the State codes and finding the parts needed for hobby use. Search for “exemptions” “hobby” “model” “miniature” “state special” “historic”.

I have not been able in all cases to find exemptions for the model hobby type boilers I do not know if this means the full code applies to model hobby use or not.

NB-370, National Board Synopsis
This is a synopsis of boiler law for all of North America including Canada and Puerto Rico, but it does not cover hobby boilers. I used this source for the name of the laws listed after each state name.

State Boiler Law Info:

Title 25. Labor, Chapter 12. The Boiler and Pressure Vessel Safety Act,
Sections 25.12.1 through 25.12.22.
25-12-7 Exemptions (I do not see a miniature hobby boiler exception)

Statutes of Alaska, Title 18. Labor and Workforce Development, Part 4. Occupational Safety and Health,
Chapter 10. Boiler and Pressure Vessel Construction Code.
Sec. 18.60.210 Exemptions
(7) manually fired miniature boilers for model locomotive, boat, tractor, or stationary
engines constructed or maintained as a hobby for exhibition use, having a volume less
than five cubic feet and grate area less than two square feet and equipped with an
American Society of Mechanical Engineers coded safety valve of adequate capacity and
size, a water level indicator, and pressure gauge;

Arizona Revised Statutes, Title 23. Labor, Article 11. Arizona Boiler Act, Sections 471 through 488.
R20-5-429 Variance
A. Any owner or user may apply to the Director for a variance from the requirements of this Article, upon demonstrating the construction, installation, and operation of the boiler or pressure vessel will maintain the same level of safety as prescribed by this Chapter. The Director shall issue a variance if the Director determines that the proponent of the variance has demonstrated the construction, installation, and operation of the boiler or pressure vessel will maintain the same level of safety as prescribed by this Chapter. The variance issued shall prescribe the construction, installation, operation, maintenance, and repair conditions that the owner or user shall maintain.

Arkansas Code 20-23-101et seq.; and 5-64-1301 through 1303.
010.01-019 A9 State Special
“State Specials” can be any boiler or fired/unfired pressure vessel of any type or
size, which carries neither the ASME symbol nor National Board stamping, and which has
otherwise been proven acceptable to the Chief Boiler Inspector and assigned an Arkansas state
010.01-010 General Requirements and Exemptions
D. Exemptions from permit and inspection
10. Coil Type Steam Generators that do not have accumulator drum. Coil-type hot
water boilers where the water can flash into steam when released directly to the atmosphere
through a manually operated nozzle may be exempted from these Rules provided the following
conditions are met:
1. There is no drum, header, or other steam space;
2. No steam is generated within the coil;
3. Tubing outside diameter does not exceed 1 inch;
4. Pipe size does not exceed nominal pipe size ¾;
5. Nominal water capacity does not exceed six (6) gallons;
6. Water temperature does not exceed 350 degrees Fahrenheit; and
7. Adequate safety relief valves and controls are provided.

California Code of Regulations, Title 8. Chapter 4. Division of Industrial Safety, Subchapter 2. Boiler and Fired Pressure Vessel Safety, Sections 750 through 797.
771. Boilers Not Subject to Annual Inspection.
 (2) Miniature boilers.
753. Definitions.
Miniature Boiler: A boiler which does not exceed any of the following limits:
16 inches inside diameter of shell.
5 cubic feet gross volume, exclusive of casing and insulation. (This volume includes the total volume of the steam and water containing parts of the boiler plus the volume of the combustion space and gas passages up to the point of attachment of the smokestack or chimney breeching.)
20 square feet water heating surface.
100 psi maximum allowable working pressures.

Colorado Revised Statutes, Title 9. Safety — Industrial and Commercial, Article 4. Buildings and Equipment, Boiler Inspection.

9-4-104. Exemptions (I do not see a miniature hobby boiler exemption)

Connecticut General Statutes, Chapter 540, An Act Concerning Boiler Inspection, Sections 29-231 through 29-244.
Sec. 29-231. (Formerly Sec. 19-426). Exceptions. The provisions of this chapter shall not apply to: (6) antique or model boilers used in public, nonprofit engineering or scientific museums and operated for educational, historical or exhibition purposes having a shell diameter of less than twelve inches and a grate surface area of less than one square foot;

Delaware Code, Title 7 Conservation Chapter 74B.
Department of Natural Resources and Environmental Control, Section 7401B Boiler Safety Program.
5.3 State Special. If a boiler, pressure vessel or nuclear component is of special design and can not be built to the ASME Code, and have the ASME Code Symbol, and National Board or USER stampings, a permit for a State Special must be applied for in writing by the Delaware user. Blueprints, design data, calculations and specifications shall be prepared by a Registered Professional Engineer, knowledgeable in the appropriate Code of Construction, and submitted to the Boiler Safety Program prior to construction.

Florida Statutes, Title 33. Regulations of Trade, Commerce, Investments and Solicitations, Chapter 554. Boiler Safety, Sections 101.1 through 115.0.

Official Code of Georgia Annotated, Title 25. Labor, Chapter 15 Article 2. Regulations of Boilers and Pressure Vessel Safety Act, Chapter 120-3-26. Georgia Boiler and Pressure Vessel Rules.
300-6-1-.11 George State special boilers
300-6-1.12 Non-conforming or non-standard boilers

Statutes of Hawaii, Title 12. Department of Labor and Industrial Relations, Subtitle 8. Division of Occupational Safety and Health, Part 10. Boilers and Pressure Vessels, Chapters 220 through 225.

Boiler and pressure rules repealed March 29,2010

Illinois Compiled Statutes, Health and Safety, Chapter 430. Public Safety, Subchapter 75. Boiler and Pressure Vessel Safety Act, Sections 1 through 16.
Sec. 5 (430ILCS 75/5) Exemptions
(7) Steam boilers of a miniature model locomotive, boat, tractor, or stationary engine constructed and maintained as a hobby and not for commercial use, that have an inside diameter not exceeding 12 inches and a grate area not exceeding 1 1/2 square feet, provided they are constantly attended while in operation and are equipped with a water level indicator, pressure gauge, and a safety valve of adequate capacity.

Indiana Administrative Code, Title 680. Boiler and Pressure Vessel Rules Board.
The definition of "Model Boiler" is now online for Indiana:
680 IAC 2-1-2 Title; scope; applicability; definition
(f) The term "regulated boiler or pressure vessel" does not include any of the following:
(12) Commercial toy boilers and miniature model boilers constructed as a hobby that do not exceed a size specified by the board.
680 IAC 2-4-30 "Model boiler" defined
Authority: IC 22-13-2-8
Affected: IC 22-12-4; IC 22-15-6
Sec. 30. "Model boiler" means any boiler that does not exceed any of the following limits:
(1) Two (2) cubic feet total gross volume (exclusive of casing and insulation).
(2) One and one-half (1 1/2) square feet of grate area.
(3) One hundred (100) psig maximum allowable working pressure.

Iowa Code Section 89

Kansas Statutes Annotated, Chapter 44. Labor and Industries, Kansas Boiler Safety Act, K.S.A 44-913
44-915. Act inapplicable to certain boilers and pressure vessels

Kentucky Revised Statutes, Title XIX. Public Safety and Morals, Chapter 236.00 Boiler and Pressure Vessel Safety Act, Sections .005 through .990.

Louisiana Revised Statutes, Title 23, Chapter 5, Part III, Regulations Affecting Boilers.
Under Mechanical Safety / boiler

Maine Revised Statutes, Title 32. Professions and Occupations, Chapter 131. Boilers and Pressure Vessels, Sections 15101 through 15121.

Annotated Code of Maryland, Public Safety Article, Title 12, Subtitle 9, Boiler and Pressure Vessel Safety Act. 33 Model Steam Boilers*

Explanation and worksheet
Excel spreadsheet

The General Laws of Massachusetts, Part I. Administration of the Government,
Title 20. Public Safety and Good Order, Chapter 146. Inspection of Boilers, Air Tanks, etc.

Michigan Compiled Laws, Skilled Trades Act of 2016, Sections 339.5901 through 339.5947

Minnesota Statutes – 2010, Chapters 326B.93 to 326B.998, Boilers. Minnesota Rules – Chapter 5225.

Mississippi Code, Title 45. Public Safety and Good Order, Chapter 23. Boiler and Pressure Vessel Safety.

Missouri Revised Statutes, Chapter 650. Department of Public Safety, Boiler and Pressure Vessel Act, Sections 200 through 290. Rules of Department of Public Safety, Division 40, Chapter 2, Boiler and Pressure Vessel Safety Rules.


Missouri Revised Statutes

Montana Code 2001, Title 50. Health and Safety, Chapter 60. Building Construction Standards and Chapter 74. Boiler and Steam Engines.
Nebraska Revised Statutes, Title 48. Labor, Boiler Inspection Act, Chapters 48-719 through 48-743; Nebraska Administrative Code, Title 229. Chapters 1 through 28.
48-726 (8) Boilers of a minature model locomotive or boat or tractor……

Nevada Administrative Code, Title 455C. Safety and Health.

New Hampshire
New Hampshire Revised Statutes, Annotated and Administrative Rules, New Hampshire Department of Labor, Title 12. Public Safety and Welfare, Chapter 157-A. Boilers and Pressure Vessels, Sections A1 through A14
Section 157-A:6 Exemptions.

New Jersey
New Jersey State Statutes, Title 34. Labor and Workers Compensation, Boilers and Pressure Vessels, New Jersey Administrative Code, 12:90.
12:90-4.1 Scope of subchapter

12:90-4.10 Inspection of boilers

New Mexico
 New Mexico Administrative Code, Title 14. Housing and Construction, Chapter 9. Mechanical Codes, Part 4. Boilers.

New York
New York State Laws, Labor, Chapter 31. Boilers.

North Carolina
North Carolina General Statutes, Chapter 95, Article 7A, and North Carolina Administrative Code, Title 13, Chapter 13.

North Dakota
North Dakota Statutes, Title 26.1. Insurance, Chapter 22.1. Boiler Inspection, Sections 1 through 14

Ohio Revised Code, Title 41. Labor and Industry, Chapter 4104. Division of Boiler Inspection, Chapter 4104. Boilers.

Oklahoma State Statutes, Title 40. Labor, Oklahoma Boiler and Pressure Vessel Law, Sections 141.0 through141.20 and Administrative Rules 380:25

Oregon Revised Statutes, Volume 11, Title 38. Protection from Fire, Chapter 480. Explosives, Flammable Materials, Pressure Vessels, Sections 510 through 990.
Hobby Miniature Steam Boilers 918-225-0390

The Pennsylvania Code, No. 104, Boiler and Unfired Pressure Vessel Law, Sections 1 through 17.
ASME Code adopted

3a.166. Miniature boilers and kitchen equipment

Rhode Island
Rhode Island General Law, Title 28. Labor and Labor Relations, Chapter 25. Boiler Inspections and Pressure Vessels, Sections 1 through 23.

South Carolina
South Carolina Code of Laws, Title 41. Labor and Employment, Chapter 14. Boiler Safety Act, Sections 41-14-10 through 41-14-150. ACT and Regulations as of June 13 2006.pdf

South Dakota
South Dakota Codified Laws, Title 34. Public Safety and Health, Chapter 29A. Boiler Safety, Sections 1 through 55.

Tennessee Code Annotated, Title 68. Health, Safety and Environmental Protection, Chapter 122. Boiler Inspection, Erection and Repair.

Boiler Law, Texas Health and Safety Code, Chapter 755.
Sec. 755.022. Exemptions For Certain Boilers
(a) This chapter does not apply to:
(1) boilers owned or operated by the federal government;
(2) pressure vessels or process steam generators, other than steam collection or liberation drums of process steam generators;
(3) manually fired miniature boilers that:
(A) are constructed or maintained for locomotives, boats, tractors, or stationary engines only as a hobby for exhibition, recreation, education, or historical purposes and not for commercial use;
(B) have an inside diameter of 12 inches or less or a grate area of two square feet or less; and
(C) are equipped with a safety valve of adequate size, a water level indicator, and a pressure gauge;

Utah Condensed Constitution, Title 34A. Utah Labor Code, Chapter 7. Safety, Sections 101 through 104.

Vermont Statutes Annotated, Title 20 VSA, Chapter 173, Subchapter 5.
Section 3

Code of Virginia, Title 40. Labor and Employment, Chapter 3.1. Boiler and Pressure Vessel Safety Act, Sections through and Virginia Administrative Code, Title 16. Labor and Employment, Agency 25. Safety and Health Codes Board, Chapter 40, Standards for Boiler and Pressure Vessel Certification, Sections 10 through 70 and Chapter 55, Financial Requirements for Boiler and Pressure Vessel Contract Fee Inspectors, Sections 10 through 20.
40.1-51.8. Exemptions

Rules, regulations and statutes: Chapter 296-104 WAC and Chapter 70.79 RCW.
70.79.070 Miniature hobby boilers
70.79.060 Construction, installation must conform to rules
70.79.320 Operating without inspection certificate prohibited—Penalty.

West Virginia
West Virginia Code, Chapter 21. Labor, Article 3. Safety and Welfare of Employees, Section 7. Regulation of Operation of Steam Boilers.

Pursuant to S.101.17m the Department of Safety & Professional Services, Division of Industry Services, enforces Wisconsin Administrative Code, SPS Chapter 341, Boilers and Pressure Vessels.

41.18 Exemptions from periodic inspections
41.43 Wisconsin special vessels.

No Boiler law
« Last Edit: February 11, 2020, 02:56:01 PM by Dan Rowe »

Offline Elam Works

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Re: US State Boiler Code
« Reply #1 on: April 17, 2019, 06:19:38 PM »
A nice start! Might I suggest that since the links indeed are likely to change as the source documents are moved around on the applicable State's departmental website, that you include the State's full document title as well as the relevant section/chapter heading. That way if the link goes completely sour, the title can be used to search for the document again and then one can drill down to the section/chapter title (applying to model boilers) and see if that changed too. Of course, the State could rename its boiler code document; then it would be a case of searching from scratch all over again.


Offline Jo

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Re: UK Boiler Code
« Reply #2 on: April 17, 2019, 08:56:21 PM »
The UK model Engineering organisations have something known as the Orange book :

The Examination & Testing of Miniature Steam Boilers (revised edition 2012) is known as the “Green Book”.

« Last Edit: April 18, 2019, 09:41:47 PM by Jo »
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Offline crueby

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Re: US State Boiler Code
« Reply #3 on: April 17, 2019, 09:31:50 PM »
Yup - good thoughts on the title/searching, I just clicked on the link for the NY state code, and it failed - NY changes their websites around a lot, on the tax pages they even warn you not to bookmark individual pages since they will change addresses.   :insane:

Offline b.lindsey

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Re: US State Boiler Code
« Reply #4 on: April 17, 2019, 10:37:40 PM »
Interesting stuff. I. The case of North Carolina there are 35 pages of codes/requirements, but there is a section on model/hobby boilers which surprised me. Thanks for posting the links. If I ever need them , I will now know where to look.


Offline Dan Rowe

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Re: US State Boiler Code
« Reply #5 on: April 17, 2019, 11:07:28 PM »
Doug, good point the title of the document is less likely to change. I fixed the Texas link and will be checking them all as I watch tv. It has been a few years since I made any updates as this thread is from the old website which I now have to ask an Admin. to fix.

When I retired as a Marine Engineer my plan was to build boilers. I got about 1/4 of the way through the states when I realized that I would never be comfortable with the legal liability.

I still find the subject interesting and it is good to keep up boiler law on my home turf.

Cheers Dan

Offline derekwarner

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Australian Boiler Codes
« Reply #6 on: April 18, 2019, 12:28:49 AM »
Copy of the Australian Model Boiler Safety Codes and Regulations follow

We are fortunate that our States have formed and adopted a universal AMBSC Code that covers all States in Australia, so compliance in any State is valid on production of the individual boiler Certificate Card across any Border

Clear parallels can be noted between the AMBSC and the British Orange Book

Derek L Warner - Honorary Secretary [Retired]
Illawarra Live Steamers Co-op - Australia

Offline steamboatmodel

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Re: US State Boiler Code
« Reply #7 on: April 18, 2019, 01:26:59 AM »
Thank you Derek,
I had bought copies of those, but someone borrowed them and has not returned them.
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Re: US State Boiler Code
« Reply #8 on: April 18, 2019, 08:42:24 PM »
In the United States where I live the regulation of most types of boilers is at the State level. This means that there are 51 codes one for each State and one for the US Capitol.
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Offline MJM460

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Re: US State Boiler Code
« Reply #9 on: April 19, 2019, 07:58:03 AM »
Thank goodness we only have six states plus two territories!

And the guys in NSW have done a nice job of writing a code for model boilers so the authorities can just endorse it instead of getting involved.


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Offline Dan Rowe

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Re: US State Boiler Code
« Reply #10 on: April 20, 2019, 06:06:07 PM »
long silence, then
slowly and quietly: "Jesus!"

Yes, this subject makes my head spin sometimes. I just found a NBBI (National Board of Boiler and Pressure Vessels Inspectors) synopsis of all the boiler code in the US and Canada. I did not know that NBBI was an international organization.

The first link in the opening message is the NBBI synopsis and it is the source of the title of the state regulations listed directly below each state.

I am still reading through the codes looking for miniature hobby boiler exceptions and I will copy the wording as I find it and fix the links.

Cheers Dan


Offline Craig DeShong

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Re: US State Boiler Code
« Reply #11 on: April 20, 2019, 10:34:47 PM »
Here at Central Carolina Live Steamers (North Carolina) we're due for our annual locomotive boiler inspection this Friday during the spring run.  This has become pretty routine the last few years.  The inspector wants to see the boiler filled with water and then he checks for leaks while it is cold.  Then he wants us to fire and see one of the safetys lift and then seat.  This seems to satisfy him.  Pretty easy and a relief from when we hydro tested years ago.
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