This guide covers Montana’s boiler operating engineer licences end to end: the Department of Labor and Industry’s Boiler Operator Program, the class structure of Title 50, chapter 74 — Limited Low Pressure, Low Pressure, Third, Second, and First Class, plus Agricultural and Traction — the pressure, temperature, and horsepower ceilings that define them, the experience hours each class demands, the written examination at a seventy percent minimum under the Administrative Rules of Montana, and the seventy dollar application and thirty-five dollar renewal, as published by the Department and in ARM Title 24, chapter 122.
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The licence 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 |
Montana classifies its boiler engineers by what is inside the boiler — pressure, temperature, and the horsepower of the machinery the steam drives — and it examines every one of them in writing, locally, at a state Job Service office. This guide follows the Department of Labor and Industry’s published system in full: the class envelopes, the experience hours and course routes beneath them, the seventy percent examination rule, the retake calendar, and the short renewal season each February and March.
The regulator and the law behind the licence
The Boiler Operator Program sits in the Department of Labor and Industry — its licensing pages carry the program under the Department’s professional licensing and building-codes administration — and its law is Title 50, chapter 74: part 3 for licences, from the requirement to hold one, through the classification and qualification sections, to examinations and fees. The Administrative Rules at Title 24, chapter 122 carry the working machinery: the fee schedule at 24.122.401, training-course approval at 24.122.405 — which sets the minimum course hours and instructor qualifications — and examinations at 24.122.510.
Two features of the regulatory style matter to applicants. The Department may accept third-party testing locations and examination results from third-party agencies it authorizes, a flexibility written into the examination rule — but the default, published route is the Job Service administration described in this guide. And the licence programme’s own page is unusually complete: classes, ceilings, experience by class, fees, renewal window, and the absence of continuing education are all stated in one place, which is why this guide can be built so closely on it.
The classes, by pressure — in full
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.
The course-plus-eight-hours route is the family’s shortest qualification anywhere in this batch: Montana built the limited licence to be earnable by the building custodian-engineer whose plant is hydronic 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.
Four hundred eighty supervised hours is one working quarter: Montana’s low pressure licence is built to be earned across a single heating season under the engineer the candidate will succeed or assist.
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.
A note on the record: the Department’s current licence page states the Third Class steam ceiling as 150 psi (with the 150 horsepower figure); an older statutory printing of the classification section states 100 psi for third class without the horsepower line. This package builds to the Department’s current page and records the difference in its INTERNAL section for the coordinator.
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.
The disappearance of the training-course route at Second Class is a policy statement: above one hundred fifty psi, Montana wants plant years, not classroom hours, behind its engineers.
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.
Agricultural and Traction licences complete the map: Agricultural covers steam boilers to one hundred fifty psi run not more than six months a year solely for harvesting or processing agricultural products, with no experience requirement; Traction covers engines and boilers on wheels, on fifty hours of traction experience plus a completed steam school, its hours creditable toward the experience.
Eligibility and experience, in full
Eligibility is arithmetic with a supervisor’s licence class attached. Every experience route specifies three things: the time (months, converted by the Department into full-time hours — 320, 480, 960, then years), the classification of boiler it was served on, and the class of licence held by the engineer it was served under. The course routes keep a supervised residue — forty hours under a licensed engineer at Low Pressure and Third Class, eight hours at Limited Low Pressure after its six-hour course — so no Montana licence is earned entirely in a classroom.
Course approval itself is regulated: a provider applies to the Department, minimum hours are set (thirty hours including classroom and field or shop time for low-pressure and third-class courses; six hours for limited low pressure), and an instructor who is not a currently licensed Montana boiler operating engineer must hold a class of licence at least equal to the training class and have passed the applicable written examination before teaching it. A candidate relying on a course should confirm its approved status with the Department before counting it.
The examination in detail
ARM 24.122.510 is short and complete: the Department may accept authorized third-party testing and results; special examinations may be arranged where the regular date conflicts with religious belief or for other appropriate reasons, on petition; applicants must complete the examination with a minimum passing score of seventy percent; and failing candidates pay a retake fee and wait a minimum of forty-five days from the last failure. The Department’s page adds the operational frame: examinations are administered at local Job Services, and applicants must be pre-approved prior to taking the examination.
No question count, time limit, or content outline is published in the rule or the Department’s page, and none is stated here. The examinable territory is the class envelope and the operation of the plant inside it — the ceilings, the controls, the firing and feedwater practice of boilers at the class’s pressures — together with the licence system itself: classes, experience, renewal, and the lawful operation rules of Title 50, chapter 74.
Applying, scheduling, and fees
The application — online through the state’s licensing portal for at least the Limited Low Pressure class, which the Department states is online only — carries the seventy dollar initial application fee that includes the examination, for all classes. The application is the pre-approval instrument: experience documents first, approval second, Job Service examination third. Candidates should apply when the arithmetic is already complete — months served, hours counted, supervisor’s class verifiable — because the approval, not the application, starts the examination clock.
Renewal and standing obligations
Renewal is annual, in a fixed season: the renewal period runs February 1 through April 1, at a thirty-five dollar renewal fee, with no continuing education requirement. The narrow window is the system’s one administrative trap: a licence missed in the season is a lapsed licence, and Montana operators should treat the February opening the way other states’ licensees treat an expiry date printed on the card.
Licences from other jurisdictions
No reciprocity or endorsement provision appears in the rules and Department pages relied on here, and none is claimed. Montana’s doors are its own: the experience routes — whose plant years are stated without regard to where they were served, and which an out-of-state engineer’s documented history may satisfy — the approved-course routes at the lower classes, pre-approval, and the seventy percent written examination at a Job Service office.
A study plan built to this examination
Master the envelopes as triplets until they are reflexive: for each class, pressure (steam), pressure and temperature (water), and horsepower where the class carries it — and the class above’s and below’s as well, because scope questions live on the boundaries. Then the arithmetic: 320, 480, and 960 hours; forty and eight supervised hours on the course routes; thirty-hour and six-hour course minima; forty-five days; seventy dollars and thirty-five; February 1 to April 1. These are the Montana paper’s certain marks.
For the operating content, study by pressure world: heating-plant practice for Limited and Low Pressure; firing, feedwater, and controls at industrial pressures for Third and Second; the whole steam plant, machinery included, for First. Practise in written form throughout — Montana’s sitting is written, and the forty-five-day cost of failure argues for arriving over-prepared rather than nearly prepared.
Examination day
Examination day is local: the pre-approved candidate sits the written examination at a Job Service office, under the Department’s arrangements, at a seventy percent line. There is no test-centre vendor machinery to learn; the discipline that matters is the paper itself and the knowledge of class envelopes it examines. A passing result completes the route the application began, and the licence issues under the Program.
A failed sitting starts the published clock — retake fee, forty-five days minimum — which the prepared candidate will treat as a study interval with a deadline, re-entering through the Department’s process when it runs.
Worked examples: the envelopes applied
A county school heats with hot water at twenty-five psig and one hundred ninety degrees, with a hot water supply boiler at one hundred twenty psig. Both limbs sit inside the Limited Low Pressure envelope — thirty psig and two hundred ten degrees for heating, one hundred sixty psig and two hundred ten degrees for supply — so the building’s operator needs the limited licence, earnable on three hundred twenty supervised hours or the six-hour approved course plus eight supervised hours, and the written examination. Montana built this class for this building.
A grain-processing plant steams at one hundred forty psi through the harvest season and stands idle the rest of the year. Two licences could describe its operator: Third Class, the general industrial rung at one hundred fifty psi — or, because the boiler runs not more than six months a year solely for harvesting and processing agricultural products, the Agricultural licence, with no experience requirement. The Agricultural class is not a lesser licence; it is a bounded one, and the boundary is the calendar and the crop.
A municipal power and heat plant with steam at two hundred psi and a ninety-horsepower steam-driven unit is Second Class plant — two hundred fifty psi ceiling, one hundred horsepower per unit — and its operator’s route there has no classroom door: two full-time years in the classification under a second or first class engineer, or the third class licence plus one such year. Montana reserves its course routes for the pressures where a heating season’s supervision suffices, and demands plant years where the steam begins to bite.
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
Why does Montana classify by pressure instead of plant size?
Because its statute does: the classes are envelopes of steam pressure, water pressure and temperature, and steam-driven machinery horsepower. Plant size enters at Third Class, whose Department-stated envelope includes 150 horsepower, but pressure is the ladder’s organizing measure.
What is the story on the Third Class pressure figure?
The Department of Labor and Industry’s current licence page states Third Class as steam boilers not in excess of 150 psi, with water boilers to 160 psi and 350 degrees and 150 horsepower. An older printing of the classification statute states 100 psi for third class. This guide follows the Department’s current page and records the discrepancy in its INTERNAL section.
Are the 480 and 960 hours part-time convertible?
The Department states the requirements as full-time experience with the hour equivalents — three months full-time (480 hours), six months full-time (960 hours). Treat the hours as the measure and confirm any part-time accumulation with the Department before relying on it.
Who may supervise my experience hours?
An engineer holding the licence class the route specifies — for Low Pressure, a valid low pressure or higher licence; for Third Class, third class or higher; for the senior classes, the second or first class engineers the routes name.
Does the seventy percent rule come from the rule or the statute?
The Administrative Rules state it: ARM 24.122.510 requires applicants to complete the examination successfully with a minimum passing score of seventy percent.
Can examinations really be held at a Job Service office?
Yes — the Department’s licence page states examinations are administered at local Job Services, with pre-approval required first. The examination rule also allows the Department to accept authorized third-party testing locations and results.
What is a steam school, for the Traction licence?
The Traction route requires at least fifty hours of experience with traction engines plus attendance and completion of a steam school; hours accrued during the steam school may be substituted for experience hours, per the Department’s page.
Is there continuing education to renew?
No. The Department’s page states there is no continuing education requirement for these licences.
What happens if I miss the April 1 renewal close?
The published renewal period is February 1 through April 1 annually; a licence not renewed in the period lapses, and reinstatement terms should be confirmed with the Department. The season is short enough that licensees should calendar its opening, not its close.
Does the application fee really include the examination?
Yes: the fee schedule at ARM 24.122.401 describes the seventy dollars as the initial application, including examination, for all classes of licensing.
May a third-party examination substitute for the Job Service sitting?
The examination rule permits the Department to accept third-party testing locations and results from agencies it authorizes. That acceptance is the Department’s, and candidates should confirm the current position when they apply.
Is the Agricultural licence a shortcut into process steam work?
No. It is bounded by its terms: steam to 150 psi, not more than six months of operation a year, and only for harvesting or processing agricultural products.
What age must I be?
Eighteen years of age or older, per the Department’s licensing information.
Does this program document my experience or take the place of a training course?
No. Experience and approved training are licensing requirements administered by the Department. This program prepares candidates for the written examination only.