Nevada Boiler Operator Licensing Exam
Practice Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. What is the primary purpose of a boiler safety valve?
A. To regulate fuel flow
B. To control water level
C. To prevent excessive pressure buildup
D. To improve combustion efficiency
A safety valve is designed to automatically release steam when
pressure exceeds safe operating limits, preventing explosion or
equipment damage.
2. Which gauge is used to measure boiler steam pressure?
A. Thermometer
B. Flow meter
C. Water column
D. Pressure gauge
A pressure gauge provides a direct reading of steam pressure inside
the boiler system.
3. Low water level in a boiler can result in:
A. Increased efficiency
B. Overheating and damage to the boiler
C. Reduced fuel consumption
D. Improved steam quality
Insufficient water can expose heating surfaces, causing overheating,
metal failure, and potential explosion.
4. The function of a blowdown valve is to:
A. Increase pressure
, B. Add chemicals
C. Remove sludge and sediment
D. Control combustion air
Blowdown removes accumulated impurities to maintain water
quality and efficiency.
5. Boiler water treatment primarily prevents:
A. Steam formation
B. Scale and corrosion
C. Fuel combustion
D. Pressure increase
Proper water treatment reduces mineral buildup and corrosion inside
the boiler.
6. A flame failure in a boiler should trigger:
A. Increased fuel supply
B. Manual restart immediately
C. Automatic shutdown of fuel supply
D. Opening of the safety valve
Safety controls must shut off fuel to prevent unburned gas
accumulation and explosion.
7. The water level in a boiler is commonly observed using a:
A. Thermocouple
B. Manometer
C. Sight glass
D. Flow switch
A sight glass allows visual monitoring of the boiler’s water level.
8. Excessive soot buildup reduces boiler:
A. Water level
B. Heat transfer efficiency
C. Pressure rating
D. Valve capacity
Soot acts as insulation, reducing heat transfer and efficiency.
9. The term “boiler horsepower” refers to:
A. Engine power
B. Electrical output
C. Boiler steam production capacity
, D. Fuel pressure
Boiler horsepower measures the boiler’s ability to produce steam.
10. A pressure relief valve should be tested:
A. Yearly only
B. Never
C. According to manufacturer and code requirements
D. Only after failure
Regular testing ensures proper operation and compliance with safety
standards.
11. Hard water in boilers leads to:
A. Increased steam quality
B. Scale formation
C. Lower pressure
D. Faster combustion
Hard water minerals deposit as scale, reducing efficiency and causing
damage.
12. The combustion process requires fuel and:
A. Water
B. Steam
C. Oxygen
D. Nitrogen
Oxygen is essential for proper fuel combustion.
13. A boiler’s operating pressure should be:
A. Above safety valve setting
B. Below the safety valve setting
C. Equal to atmospheric pressure
D. Uncontrolled
Operating pressure must remain below relief settings for safety.
14. Carbon monoxide is dangerous because it:
A. Is visible
B. Has odor
C. Is toxic and odorless
D. Is nonflammable
Carbon monoxide is a poisonous gas that cannot be detected by
smell.
Practice Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. What is the primary purpose of a boiler safety valve?
A. To regulate fuel flow
B. To control water level
C. To prevent excessive pressure buildup
D. To improve combustion efficiency
A safety valve is designed to automatically release steam when
pressure exceeds safe operating limits, preventing explosion or
equipment damage.
2. Which gauge is used to measure boiler steam pressure?
A. Thermometer
B. Flow meter
C. Water column
D. Pressure gauge
A pressure gauge provides a direct reading of steam pressure inside
the boiler system.
3. Low water level in a boiler can result in:
A. Increased efficiency
B. Overheating and damage to the boiler
C. Reduced fuel consumption
D. Improved steam quality
Insufficient water can expose heating surfaces, causing overheating,
metal failure, and potential explosion.
4. The function of a blowdown valve is to:
A. Increase pressure
, B. Add chemicals
C. Remove sludge and sediment
D. Control combustion air
Blowdown removes accumulated impurities to maintain water
quality and efficiency.
5. Boiler water treatment primarily prevents:
A. Steam formation
B. Scale and corrosion
C. Fuel combustion
D. Pressure increase
Proper water treatment reduces mineral buildup and corrosion inside
the boiler.
6. A flame failure in a boiler should trigger:
A. Increased fuel supply
B. Manual restart immediately
C. Automatic shutdown of fuel supply
D. Opening of the safety valve
Safety controls must shut off fuel to prevent unburned gas
accumulation and explosion.
7. The water level in a boiler is commonly observed using a:
A. Thermocouple
B. Manometer
C. Sight glass
D. Flow switch
A sight glass allows visual monitoring of the boiler’s water level.
8. Excessive soot buildup reduces boiler:
A. Water level
B. Heat transfer efficiency
C. Pressure rating
D. Valve capacity
Soot acts as insulation, reducing heat transfer and efficiency.
9. The term “boiler horsepower” refers to:
A. Engine power
B. Electrical output
C. Boiler steam production capacity
, D. Fuel pressure
Boiler horsepower measures the boiler’s ability to produce steam.
10. A pressure relief valve should be tested:
A. Yearly only
B. Never
C. According to manufacturer and code requirements
D. Only after failure
Regular testing ensures proper operation and compliance with safety
standards.
11. Hard water in boilers leads to:
A. Increased steam quality
B. Scale formation
C. Lower pressure
D. Faster combustion
Hard water minerals deposit as scale, reducing efficiency and causing
damage.
12. The combustion process requires fuel and:
A. Water
B. Steam
C. Oxygen
D. Nitrogen
Oxygen is essential for proper fuel combustion.
13. A boiler’s operating pressure should be:
A. Above safety valve setting
B. Below the safety valve setting
C. Equal to atmospheric pressure
D. Uncontrolled
Operating pressure must remain below relief settings for safety.
14. Carbon monoxide is dangerous because it:
A. Is visible
B. Has odor
C. Is toxic and odorless
D. Is nonflammable
Carbon monoxide is a poisonous gas that cannot be detected by
smell.
