Montana licenses boiler operating engineers through its Department of Labor and Industry under Title 50, chapter 74 of the Montana Code. The classes run from Limited Low Pressure and Low Pressure through Third Class — steam to one hundred fifty psi — Second Class at two hundred fifty psi, and First Class for all classes, pressures, and temperatures, with Agricultural and Traction licences beside them. Every class requires a written examination passed at seventy percent, pre-approved by the Department and administered at local Job Service offices; the application fee covering examination is seventy dollars.
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What these licences authorize
Montana licenses the people who run its boilers as boiler operating engineers, through the Department of Labor and Industry under Title 50, chapter 74 of the Montana Code Annotated, and it classifies them by the pressure and temperature of the plant rather than its size. The ladder the Department’s Boiler Operator Program publishes runs: Limited Low Pressure, for hot water heating and supply boilers within modest pressure and temperature limits; Low Pressure, for steam boilers not over fifteen psi and water boilers not over fifty psi and two hundred fifty degrees; Third Class, for steam boilers not over one hundred fifty psi and water boilers not over one hundred sixty psi and three hundred fifty degrees, at one hundred fifty horsepower; Second Class, for steam boilers not over two hundred fifty psi, water boilers not over three hundred seventy-five psi and four hundred fifty degrees, and steam-driven machinery not over one hundred horsepower per unit; and First Class, for all classes, pressures, and temperatures of steam and water boilers and steam-driven machinery — traction and hoisting engines excepted throughout. Agricultural and Traction licences stand beside the ladder for their seasonal and wheeled plant.
Every class on the ladder is examined: the Administrative Rules of Montana require applicants to complete the examination successfully with a minimum passing score of seventy percent, examinations are administered at local Job Service offices, and applicants must be pre-approved before taking the examination. Experience is counted in the Department’s preferred units — months and full-time hours: four hundred eighty hours under a licensed engineer for Low Pressure, nine hundred sixty for Third Class, two years for Second, three years for First — with approved training courses standing in place of part of the supervised time at the ladder’s lower rungs.
The examination at a glance
| Item | Verified position |
|---|---|
| Licences | Montana Boiler Operating Engineer licences — Limited Low Pressure, Low Pressure, Third Class, Second Class, First Class; plus Agricultural and Traction engineer licences |
| Regulator | Montana Department of Labor and Industry, Boiler Operator Program (Professional Licensing / Building Codes administration) |
| Legal basis | Montana Code Annotated Title 50, chapter 74, part 3 (licences); Administrative Rules of Montana Title 24, chapter 122 (Boiler Operating Engineers) |
| Limited Low Pressure | Hot water heating boilers not over 30 psig and 210 degrees F; hot water supply boilers not over 160 psig and 210 degrees F |
| Low Pressure | Steam boilers operated not in excess of 15 psi; water boilers not in excess of 50 psi and 250 degrees F |
| Third Class | Steam boilers not in excess of 150 psi; water boilers not in excess of 160 psi and 350 degrees F; and 150 horsepower (Department’s licence page) |
| Second Class | Steam boilers not in excess of 250 psi; water boilers not in excess of 375 psi and 450 degrees F; steam-driven machinery not to exceed 100 horsepower per unit, except traction and hoisting engines |
| First Class | All classes, pressures, and temperatures of steam and water boilers and steam-driven machinery, except traction-hoisting engines |
| Agricultural | Steam boilers not in excess of 150 psi, operated not more than six months of the year, and only for harvesting or processing agricultural products; no experience requirement |
| Traction | Traction engines or boilers on wheels; at least fifty hours of traction experience and completion of a steam school |
| Examination | Written examination required for all classes of licensing; minimum passing score seventy percent (70%) under ARM 24.122.510; administered at local Job Service offices; pre-approval required; retake after failure requires a minimum forty-five-day wait and a retake fee |
| Application fee | Seventy dollars ($70) for initial application including examination, for all classes of licensing (ARM 24.122.401 fee schedule and the Department’s page) |
| Experience (headline) | Limited Low Pressure: two months full-time (320 hours) or a 6-hour approved course plus 8 hours under a licensed engineer. Low Pressure: three months full-time (480 hours) or an approved course plus 40 hours. Third Class: six months full-time (960 hours) or an approved course plus 40 hours. Second Class: two years full-time in class, or Third Class licence plus one year. First Class: three years full-time in class, or Second Class plus one year, or Third Class plus two years |
| Age and renewal | Must be eighteen years of age or older; renewal period annually February 1 through April 1; renewal fee $35; no continuing education requirement |
The classes, by pressure
Montana’s classes divide the boiler world by what is inside the boiler — its pressure, temperature, and (at the machinery classes) the horsepower of the steam-driven units — and each class below states its envelope and the experience the Department’s page requires for it.
Limited Low Pressure — the hot-water licence
The newest and narrowest rung: hot water heating boilers not over thirty psig and two hundred ten degrees, and hot water supply boilers not over one hundred sixty psig and two hundred ten degrees. It licenses the operator of the modern hydronic building — the school, clinic, and commercial block heated and supplied with hot water — without requiring the steam curriculum. Experience is correspondingly light: two months of full-time experience (three hundred twenty hours) operating a boiler in this classification under a licensed engineer, or completion of a six-hour approved training course specific to limited low pressure boilers plus a minimum of eight hours of experience under a licensed boiler engineer — and the written examination. The Department notes this application is available online only.
Low Pressure — steam to 15 psi
The classic heating-plant licence: steam boilers operated not in excess of fifteen psi, and water boilers not in excess of fifty psi and two hundred fifty degrees. Qualification: three months of full-time experience (four hundred eighty hours) in the operation of a boiler in this classification under an engineer holding a valid low pressure or higher licence, or completion of a Department-approved training course specific to low pressure boilers plus a minimum of forty hours of experience under a licensed boiler engineer — and the written examination. Minimum approved course length at this level is thirty hours of classroom and field or shop time under the training-course rule.
Third Class — steam to 150 psi, 150 horsepower
The first industrial rung: steam boilers not in excess of one hundred fifty psi, water boilers not in excess of one hundred sixty psi and three hundred fifty degrees, and one hundred fifty horsepower, as the Department’s licence page states the class. Qualification: six months of full-time experience (nine hundred sixty hours) operating a boiler in this classification under an engineer holding a valid third class or higher licence, or an approved third-class training course plus forty hours under a licensed engineer — and the written examination. Thirty hours is likewise the minimum approved course length for third-class training.
Second Class — steam to 250 psi, machinery to 100 horsepower
Second Class reaches the true power plant: steam boilers not in excess of two hundred fifty psi, water boilers not in excess of three hundred seventy-five psi and four hundred fifty degrees, and steam-driven machinery not to exceed one hundred horsepower per unit — traction and hoisting engines excepted. There is no course shortcut at this altitude: qualification is two years of full-time experience operating a boiler in this classification under an engineer holding a valid second or first class licence, or a valid third class licence plus at least one year of full-time actual experience operating in this classification under a second or first class engineer — and the written examination.
First Class — all classes, pressures, and temperatures
The unlimited licence: all classes, pressures, and temperatures of steam and water boilers and steam-driven machinery, traction-hoisting engines alone excepted. Qualification: three years of full-time experience operating a boiler in this classification under a first class engineer; or a valid second class licence with at least one year of full-time actual experience in this classification under a first class engineer; or a valid third class licence with at least two years of full-time experience in this classification under a first class engineer — and the written examination. The First Class engineer is Montana’s chief in fact: the licence under whom second and third class candidates serve the very years their own promotions require.
Who this licence serves
Montana’s classes serve a dispersed state’s boiler workforce: school and hospital heating plants in county towns, food-processing and agricultural steam — the Agricultural licence exists for the harvest-season boiler and says so — sawmill and industrial plant, and the traction-engine community of steam heritage whose engines the Traction licence and steam schools serve. The Job Service examination geography matches that dispersion: the state examines where its workforce already goes for work services, not only in Helena.
The pressure-class structure suits Montana plant: most of the state’s boilers are heating and small process boilers whose hazard is their pressure, and the ladder’s lower, course-accessible rungs are how a rural workforce gets licensed without leaving the county for a year.
The route, in order
Apply to the Department first: the application — seventy dollars for the initial application including examination, for all classes — presents the experience case, in the class’s stated months and hours, or the approved-course route where the class allows it. Pre-approval follows; only the pre-approved applicant may take the examination. The written examination is then administered at local Job Service offices, and the passing line is seventy percent under ARM 24.122.510.
Failure has a published cost and calendar: the failing candidate pays a retake fee — the fee schedule sets the retake at fifty percent of the application fee — and waits a minimum of forty-five days from the last failure before retaking. Licensing runs on an annual renewal period of February 1 through April 1 at thirty-five dollars, with no continuing education requirement, and the licensee must be eighteen or older at entry.
What makes this examination demanding
Montana’s examination is one written paper at seventy percent for every class, and its demand is the class envelope’s exactness. The ceilings are triplets — pressure, temperature, and at the higher classes horsepower per unit — and they differ by class in ways a rounded memory will blur: fifteen and fifty psi at Low Pressure; one hundred fifty psi and one hundred fifty horsepower at Third; two hundred fifty and three hundred seventy-five psi, four hundred fifty degrees, one hundred horsepower per unit at Second. The candidate who cannot state their class’s envelope, and the class above’s, does not yet hold the licence’s map.
The experience arithmetic is the second demand, and it is audited before the examination, not after: months converted to full-time hours — three hundred twenty, four hundred eighty, nine hundred sixty — the licensed class of the supervising engineer, the course hours the rules set as minima, and the forty or eight supervised hours that survive even the course routes. Montana pre-approves, so the candidate’s paperwork is examined before the candidate is.
The credential at work
A Montana class tells an employer the pressure world its holder may run, which is the question Montana plants actually ask: the heating plant needs its Low Pressure engineer each winter; the process plant needs Third or Second; the largest steam users need First. The annual February-to-April renewal gives the credential a seasonal rhythm matched to the heating year, and the licence’s portability across the state’s small labour markets — the same classes in every county, examined at the local Job Service — makes it the rural boiler workforce’s standard credential.
What the PassProfessor program will cover
Practice in the examination’s own shape. Montana’s examination is a written sitting, pre-approved by the Department and administered at local Job Service offices, passed at seventy percent. The program in the works practises in that shape: single-best-answer items and timed sets organized by class envelope — pressure, temperature, and horsepower ceilings class by class — with the experience-hour arithmetic and the licence map drilled as Montana’s administrative core.
Written from the primary sources. The program is written from the Department of Labor and Industry’s Boiler Operator Program licence pages, the fee and examination rules at ARM 24.122.401 and 24.122.510, and the classification structure of Title 50, chapter 74. Where Montana’s pressure classes differ from other states’ horsepower grades, the program teaches the Montana envelopes and names the difference.
The whole candidate, not only the test-taker. Around the item practice, the program carries the Boiler Operator Program route as the authority publishes it — Department pre-approval on documented experience, the written examination at seventy percent, and the annual renewal window — because a written examination is a means to a licence, and candidates plan better when the destination is mapped.
Preparation only. This is preparation for the written examination administered under the Montana Department of Labor and Industry’s Boiler Operator Program. PassProfessor is not affiliated with the Department, no completion of this program is reported to the Department, and nothing in the program substitutes for the supervised experience or approved training any class requires, or for any step in the licensing process.
Tell me when enrollment opens. The Montana Boiler Operating Engineer program is in the works and enrollment is not yet open. Leave an email address and PassProfessor will write to you when the program is ready — and only about this program. No date is promised, because the program will open when it meets the standard described above, not before.
Frequently asked questions
Who licenses Montana boiler operating engineers?
The Montana Department of Labor and Industry, through its Boiler Operator Program, under Title 50, chapter 74 of the Montana Code and ARM Title 24, chapter 122.
What classes are there?
Limited Low Pressure, Low Pressure, Third Class, Second Class, and First Class — plus Agricultural and Traction engineer licences beside the ladder.
What are the headline ceilings?
Low Pressure: steam to 15 psi. Third Class: steam to 150 psi and 150 horsepower (Department’s page). Second Class: steam to 250 psi, steam-driven machinery to 100 horsepower per unit. First Class: all classes, pressures, and temperatures.
Must every class take an examination?
Yes. The Department states the written examination is required for all classes of licensing, and ARM 24.122.510 sets the minimum passing score at seventy percent.
Where is the examination given?
At local Job Service offices, and only after the Department pre-approves the application.
What does it cost?
The initial application, including examination, is seventy dollars for all classes of licensing — a Department fee. Renewal is thirty-five dollars in the annual February 1 to April 1 renewal period.
Can a training course replace experience?
Partly, at the lower rungs: approved courses plus reduced supervised hours (forty hours at Low Pressure and Third Class; eight hours with the six-hour course at Limited Low Pressure) substitute for the full supervised-experience routes. Second and First Class publish no course route — they require plant years.
What if I fail?
A retake fee applies — the fee schedule sets it at fifty percent of the application fee — and you must wait a minimum of forty-five days from the last failure before retaking.
What is the Agricultural licence?
For steam boilers not over 150 psi operated not more than six months of the year solely for harvesting or processing agricultural products. It has no experience requirement.
Is PassProfessor affiliated with the Montana Department of Labor and Industry?
No. PassProfessor is an independent preparation provider. The program confers no licence and reports nothing to the Department.