Licensing Examination Practice

Illinois High-Pressure Boiler Operator Licensing Examination Practice Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

Q1. What is the primary purpose of a high-pressure boiler?

• Heat residential buildings
• Warm domestic water
• Supply low-pressure steam only
• Generate steam or hot water at high pressures for industrial processes

Rationale: High-pressure boilers are designed to produce high-pressure

steam essential for industrial power, process heating, and turbines.

Q2. High-pressure steam boilers are defined as boilers operating above what pressure? 1 / 4

• 10 psi
• 15 psi
• 15 psi steam pressure
• 5 psi

Rationale: ASME defines high-pressure steam boilers as those operating

above 15 psi.

Q3. The device that prevents boiler pressure from exceeding the maximum

allowable working pressure (MAWP) is the:

• Blowdown valve
• Feedwater valve
• Safety valve
• Gauge glass

Rationale: Safety valves automatically release steam to prevent

overpressure conditions.

Q4. A boiler’s MAWP is found on the:

• Water column
• Blowdown tank
• ASME data plate
• Low-water cutoff

Rationale: The ASME nameplate lists MAWP and key boiler specifications. 2 / 4

Q5. What is the minimum number of gauge glasses required on a high- pressure steam boiler?

• None
• One
• One if equipped with remote indicators
• Three

Rationale: Most require one gauge glass; remote indication systems allow

exceptions per code.

Q6. The low-water cutoff (LWCO) is designed to:

• Relieve excess pressure
• Shut the burner off if water level drops too low
• Add chemicals automatically
• Control combustion airflow

Rationale: LWCO prevents boiler firing when water levels are unsafe,

avoiding catastrophic failure.

Q7. What action is required before blowing down a boiler?

• Increase firing rate
• Open quick-opening valve first
• Open slow-opening valve first 3 / 4

• Shut down the boiler completely

Rationale: The quick-opening valve is opened first to allow safe isolation

and control.

Q8. Boiler tubes that carry water surrounded by hot gases are part of which boiler type?

• Firetube
• Watertube
• Cast iron sectional
• Electric

Rationale: Watertube boilers circulate water inside tubes exposed to

combustion gases.

Q9. Steam pressure is measured using a:

• Draft gauge
• Bourdon tube gauge
• Tachometer
• Hygrometer

Rationale: Bourdon tube gauges are standard for steam pressure readings.

Q10. What is the primary purpose of boiler blowdown?

• / 4