Pass the State Boiler Operator License Exam.

What is the boiler operator license exam?

Most states require boiler operators and stationary engineers to pass a state licensing exam before operating high-pressure boilers. The exam covers boiler types (fire-tube, water-tube), combustion principles, water treatment, safety valves, ASME boiler codes, and emergency procedures. Exams are typically administered by state labor or DOLI departments.

What are the boiler operator license grades?

Most states issue tiered boiler operator licenses by boiler capacity and pressure. Common grades include: Low Pressure (under 15 psi steam), High Pressure (over 15 psi steam), and Stationary Engineer (high-pressure boilers over a specified horsepower). Higher grades require more experience and often more difficult exams.

How hard is the boiler operator exam?

Pass rates vary by state and grade but typically range from 55–70% for first-time candidates. The most difficult sections are boiler water treatment chemistry, heat transfer calculations, and ASME code compliance. Candidates who study boiler operation manuals and practice calculation problems perform significantly better.