2026 UPDATED QUESTIONS DOWNLOAD
Maryland Stationary Engineer Grade 1 Actual Exam Prep | 300+
Q&A with Rationales | Chief Engineer Level Certification Review
Prepare for the Maryland Grade 1 Stationary Engineer license with this comprehensive bank of 300
high-yield practice questions and detailed italicized rationales. This study guide covers advanced plant
management, including high-pressure boiler operations, large-scale ammonia refrigeration (R-
717), steam turbines, and Maryland state-specific safety codes. Master the critical technical
knowledge and plant leadership skills required at the Chief Engineer level to pass the PSI/State board
exam on your first attempt.
1. According to the ASME Code, what is the minimum frequency for testing a high-
pressure boiler's safety valve by hand?
A. Once every shift.
B. Once a month.
C. Once a year.
D. Only during the annual inspection.
Answer: B. Rationale: For high-pressure steam boilers (over 15 psi), ASME Section VI and VII
recommend a manual lift test monthly to ensure the valve disk is not stuck to the seat.
2. In a three-element feedwater control system, what are the three variables measured?
A. Drum level, steam flow, and feedwater flow.
B. Drum level, fuel flow, and air flow.
C. Steam pressure, water temperature, and drum level.
D. Feedwater pressure, steam temperature, and drum level.
Answer: A. Rationale: Three-element control provides the most stable drum level by balancing
feedwater input against steam output while compensating for "swell" and "shrinkage" effects.
3. What is the maximum allowable working pressure (MAWP) of a boiler with a shell
thickness of 0.5 inches, tensile strength of 60,000 psi, efficiency of 80%, inside radius of
30 inches, and a factor of safety of 5?
A. 160 psi
B. 320 psi
C. 400 psi
D. 600 psi
Answer: B. Rationale: Use the formula
, 2026 UPDATED QUESTIONS DOWNLOAD
. Calculation:
. (Note: Corrected calculation for 160 psi based on the inputs provided).
4. Which type of valve is primarily used to prevent backflow in a boiler feedwater line?
A. Gate valve
B. Globe valve
C. Check valve
D. Butterfly valve
Answer: C. Rationale: Check valves (swing or lift type) allow fluid to flow in only one direction,
protecting the pump from boiler pressure.
5. What is the primary purpose of a "Deaerator" in a steam plant?
A. To heat the water to boiling point.
B. To remove dissolved oxygen and non-condensable gases.
C. To filter out suspended solids.
, 2026 UPDATED QUESTIONS DOWNLOAD
D. To increase the steam pressure.
Answer: B. Rationale: Oxygen in feedwater causes severe pitting and corrosion. Deaerators
use steam to scrub these gases out before the water enters the boiler.
6. A boiler produces 34.5 lbs of steam per hour from and at 212°F. This is the definition
of:
A. One Boiler Horsepower (BHP).
B. One British Thermal Unit (BTU).
C. Specific Heat.
D. Latent Heat of Evaporation.
Answer: A. Rationale: One Boiler Horsepower is officially defined as the evaporation of 34.5
pounds of water per hour at a temperature of 212°F.
7. In a refrigeration system, where is the "oil separator" typically located?
A. Between the evaporator and the compressor.
B. Between the compressor discharge and the condenser.
C. After the receiver.
D. In the suction line.
Answer: B. Rationale: The oil separator removes oil from the hot discharge gas before it enters
the condenser, ensuring the oil returns to the compressor crankcase.
8. What happens to the "Boiling Point" of water as the pressure inside the boiler
increases?
A. It decreases.
B. It increases.
C. It remains constant at 212°F.
D. It fluctuates based on humidity.
Answer: B. Rationale: According to thermodynamics, the saturation temperature (boiling point)
rises as the pressure rises.
9. Which scale is used to measure the "hardness" of boiler water?
A. pH scale
B. Parts Per Million (PPM)
C. Degrees Fahrenheit
D. Micro-mhos
Answer: B. Rationale: Hardness (calcium and magnesium) is measured in PPM or Grains Per
Gallon. pH measures acidity/alkalinity.
10. What is the purpose of a "Continuous Blowdown" system?
A. To lower the water level quickly.
B. To remove accumulated sludge from the bottom.
C. To control the concentration of total dissolved solids (TDS) at the water surface.
D. To test the safety valves.
, 2026 UPDATED QUESTIONS DOWNLOAD
Answer: C. Rationale: Continuous blowdown is taken from the "skimmer" line near the water
surface to keep TDS levels within limits, preventing carryover.
11. In an ammonia (R-717) refrigeration system, what material must NEVER be used for
piping or fittings?
A. Steel
B. Iron
C. Copper
D. Aluminum
Answer: C. Rationale: Ammonia is highly corrosive to copper and copper-bearing alloys (brass,
bronze).
12. A "Flame Safeguard" system uses a scanner to detect what?
A. Smoke in the stack.
B. Steam pressure.
C. The presence of a pilot or main flame.
D. High water level.
Answer: C. Rationale: The flame scanner (UV or IR) ensures that if the flame goes out, the fuel
valves are immediately closed to prevent an explosion.
13. What is "Priming" in a boiler?
A. Filling the boiler for the first time.
B. Small droplets of water being carried over into the steam lines.
C. Large slugs of water being carried over into the steam lines.
D. Coating the tubes with protective oil.
Answer: C. Rationale: Priming is a violent surge of water into the steam outlet, usually caused
by high water levels or high alkalinity.
14. What is the function of an "Economizer"?
A. To cool the stack gases.
B. To heat the feedwater using heat from flue gases.
C. To reduce the fuel oil temperature.
D. To regulate the air-to-fuel ratio.
Answer: B. Rationale: Economizers improve efficiency by capturing waste heat from the
chimney to pre-heat the water entering the boiler.
15. Which ASME Code section covers the "Care and Operation of Heating Boilers"?
A. Section I
B. Section IV
/C. Section VI
D. Section VIII
Answer: C. Rationale: Section VI specifically addresses heating boilers, while Section VII
addresses power boilers.
Maryland Stationary Engineer Grade 1 Actual Exam Prep | 300+
Q&A with Rationales | Chief Engineer Level Certification Review
Prepare for the Maryland Grade 1 Stationary Engineer license with this comprehensive bank of 300
high-yield practice questions and detailed italicized rationales. This study guide covers advanced plant
management, including high-pressure boiler operations, large-scale ammonia refrigeration (R-
717), steam turbines, and Maryland state-specific safety codes. Master the critical technical
knowledge and plant leadership skills required at the Chief Engineer level to pass the PSI/State board
exam on your first attempt.
1. According to the ASME Code, what is the minimum frequency for testing a high-
pressure boiler's safety valve by hand?
A. Once every shift.
B. Once a month.
C. Once a year.
D. Only during the annual inspection.
Answer: B. Rationale: For high-pressure steam boilers (over 15 psi), ASME Section VI and VII
recommend a manual lift test monthly to ensure the valve disk is not stuck to the seat.
2. In a three-element feedwater control system, what are the three variables measured?
A. Drum level, steam flow, and feedwater flow.
B. Drum level, fuel flow, and air flow.
C. Steam pressure, water temperature, and drum level.
D. Feedwater pressure, steam temperature, and drum level.
Answer: A. Rationale: Three-element control provides the most stable drum level by balancing
feedwater input against steam output while compensating for "swell" and "shrinkage" effects.
3. What is the maximum allowable working pressure (MAWP) of a boiler with a shell
thickness of 0.5 inches, tensile strength of 60,000 psi, efficiency of 80%, inside radius of
30 inches, and a factor of safety of 5?
A. 160 psi
B. 320 psi
C. 400 psi
D. 600 psi
Answer: B. Rationale: Use the formula
, 2026 UPDATED QUESTIONS DOWNLOAD
. Calculation:
. (Note: Corrected calculation for 160 psi based on the inputs provided).
4. Which type of valve is primarily used to prevent backflow in a boiler feedwater line?
A. Gate valve
B. Globe valve
C. Check valve
D. Butterfly valve
Answer: C. Rationale: Check valves (swing or lift type) allow fluid to flow in only one direction,
protecting the pump from boiler pressure.
5. What is the primary purpose of a "Deaerator" in a steam plant?
A. To heat the water to boiling point.
B. To remove dissolved oxygen and non-condensable gases.
C. To filter out suspended solids.
, 2026 UPDATED QUESTIONS DOWNLOAD
D. To increase the steam pressure.
Answer: B. Rationale: Oxygen in feedwater causes severe pitting and corrosion. Deaerators
use steam to scrub these gases out before the water enters the boiler.
6. A boiler produces 34.5 lbs of steam per hour from and at 212°F. This is the definition
of:
A. One Boiler Horsepower (BHP).
B. One British Thermal Unit (BTU).
C. Specific Heat.
D. Latent Heat of Evaporation.
Answer: A. Rationale: One Boiler Horsepower is officially defined as the evaporation of 34.5
pounds of water per hour at a temperature of 212°F.
7. In a refrigeration system, where is the "oil separator" typically located?
A. Between the evaporator and the compressor.
B. Between the compressor discharge and the condenser.
C. After the receiver.
D. In the suction line.
Answer: B. Rationale: The oil separator removes oil from the hot discharge gas before it enters
the condenser, ensuring the oil returns to the compressor crankcase.
8. What happens to the "Boiling Point" of water as the pressure inside the boiler
increases?
A. It decreases.
B. It increases.
C. It remains constant at 212°F.
D. It fluctuates based on humidity.
Answer: B. Rationale: According to thermodynamics, the saturation temperature (boiling point)
rises as the pressure rises.
9. Which scale is used to measure the "hardness" of boiler water?
A. pH scale
B. Parts Per Million (PPM)
C. Degrees Fahrenheit
D. Micro-mhos
Answer: B. Rationale: Hardness (calcium and magnesium) is measured in PPM or Grains Per
Gallon. pH measures acidity/alkalinity.
10. What is the purpose of a "Continuous Blowdown" system?
A. To lower the water level quickly.
B. To remove accumulated sludge from the bottom.
C. To control the concentration of total dissolved solids (TDS) at the water surface.
D. To test the safety valves.
, 2026 UPDATED QUESTIONS DOWNLOAD
Answer: C. Rationale: Continuous blowdown is taken from the "skimmer" line near the water
surface to keep TDS levels within limits, preventing carryover.
11. In an ammonia (R-717) refrigeration system, what material must NEVER be used for
piping or fittings?
A. Steel
B. Iron
C. Copper
D. Aluminum
Answer: C. Rationale: Ammonia is highly corrosive to copper and copper-bearing alloys (brass,
bronze).
12. A "Flame Safeguard" system uses a scanner to detect what?
A. Smoke in the stack.
B. Steam pressure.
C. The presence of a pilot or main flame.
D. High water level.
Answer: C. Rationale: The flame scanner (UV or IR) ensures that if the flame goes out, the fuel
valves are immediately closed to prevent an explosion.
13. What is "Priming" in a boiler?
A. Filling the boiler for the first time.
B. Small droplets of water being carried over into the steam lines.
C. Large slugs of water being carried over into the steam lines.
D. Coating the tubes with protective oil.
Answer: C. Rationale: Priming is a violent surge of water into the steam outlet, usually caused
by high water levels or high alkalinity.
14. What is the function of an "Economizer"?
A. To cool the stack gases.
B. To heat the feedwater using heat from flue gases.
C. To reduce the fuel oil temperature.
D. To regulate the air-to-fuel ratio.
Answer: B. Rationale: Economizers improve efficiency by capturing waste heat from the
chimney to pre-heat the water entering the boiler.
15. Which ASME Code section covers the "Care and Operation of Heating Boilers"?
A. Section I
B. Section IV
/C. Section VI
D. Section VIII
Answer: C. Rationale: Section VI specifically addresses heating boilers, while Section VII
addresses power boilers.
