Stationary Engineer Exam – Boiler and
Plant Operations Licensing Test||
GRADED A+|| LATEST UPDATE 2025/26
High pressure steam boilers generally operate at pressures
A. above 15 psi and over 6 boiler horsepower.
B. below 15 psi and over 8 boiler horsepower.
C. above 250 psi and over 6 boiler horsepower.
D. at 212 psi and over 8 boiler horsepower. -CORRECTANSWER A. above 15 psi and
over 6 boiler horsepower.
Pressure gauges should never have a range less than
A. half the safety valve set pressure.
B. double the safety valve set pressure.
C. 3/4 times the safety valve set pressure.
D. 1 1/2 times the safety valve set pressure. -CORRECTANSWER D. 1 1/2 times the
safety valve set pressure.
After water is blown out of a siphon, why should live steam never be allowed to enter a
Bourdon tube?
A. The steam will rupture the siphon tube.
B. Combustion gases will mix with the steam.
C. Live steam will damage the pressure gauge.
,D. The water level gauge will be damaged or destroyed. -CORRECTANSWER C. Live
steam will damage the pressure gauge.
All of the following are essential to maintain the proper fuel oil pressure with fuel oil
accessories EXCEPT
A. achieving the right flow of fuel.
B. proper atomization of the fuel oil.
C. heating fuel oil to the correct temperature.
D. obtaining the correct difference in pressure inside and outside the boiler. -
CORRECTANSWER D. obtaining the correct difference in pressure inside and outside
the boiler.
Which of the following could be dangerous to safe operation of a low pressure boiler?
A. Adding water to an operating boiler when the water level cannot be seen in the
gauge glass tube.
B. Opening the blowdown valve at the bottom of the water gauge glass before making a
water level reading.
C. Checking the water level using the try cocks valves when the line to the glass gauge
tube is clogged.
D. Opening the water column blowdown valve every day. -CORRECTANSWER A.
Adding water to an operating boiler when the water level cannot be seen in the gauge
glass tube.
, Which of the following is best if a low-pressure boiler does not have an air vent?
A. Vent the boiler with the try cocks.
B. Vent the boiler with the safety valve.
C. Vent the boiler with the fusible plug.
D. Vent the boiler with the blowdown line. -CORRECTANSWER A. Vent the boiler with
the try cocks.
What is the purpose of an evaporation test on a low pressure boiler?
A. To test the water column
B. To test the bottom blowdown valve
C. To test the steam pressure safety valve
D. To test the low water cutoff control. -CORRECTANSWER D. To test the low water
cutoff control.
Following flame failure, controls must de-energize fuel and ignition circuits
A. within 4 seconds.
B. within 6 seconds.
C. within 10 seconds.
D. within 15 seconds. -CORRECTANSWER A. within 4 seconds.
How can an operator prevent damage to the tubes while using a cleaner to remove
scale from boiler tubes?
A. Never use a chemical cleaning procedure.
Plant Operations Licensing Test||
GRADED A+|| LATEST UPDATE 2025/26
High pressure steam boilers generally operate at pressures
A. above 15 psi and over 6 boiler horsepower.
B. below 15 psi and over 8 boiler horsepower.
C. above 250 psi and over 6 boiler horsepower.
D. at 212 psi and over 8 boiler horsepower. -CORRECTANSWER A. above 15 psi and
over 6 boiler horsepower.
Pressure gauges should never have a range less than
A. half the safety valve set pressure.
B. double the safety valve set pressure.
C. 3/4 times the safety valve set pressure.
D. 1 1/2 times the safety valve set pressure. -CORRECTANSWER D. 1 1/2 times the
safety valve set pressure.
After water is blown out of a siphon, why should live steam never be allowed to enter a
Bourdon tube?
A. The steam will rupture the siphon tube.
B. Combustion gases will mix with the steam.
C. Live steam will damage the pressure gauge.
,D. The water level gauge will be damaged or destroyed. -CORRECTANSWER C. Live
steam will damage the pressure gauge.
All of the following are essential to maintain the proper fuel oil pressure with fuel oil
accessories EXCEPT
A. achieving the right flow of fuel.
B. proper atomization of the fuel oil.
C. heating fuel oil to the correct temperature.
D. obtaining the correct difference in pressure inside and outside the boiler. -
CORRECTANSWER D. obtaining the correct difference in pressure inside and outside
the boiler.
Which of the following could be dangerous to safe operation of a low pressure boiler?
A. Adding water to an operating boiler when the water level cannot be seen in the
gauge glass tube.
B. Opening the blowdown valve at the bottom of the water gauge glass before making a
water level reading.
C. Checking the water level using the try cocks valves when the line to the glass gauge
tube is clogged.
D. Opening the water column blowdown valve every day. -CORRECTANSWER A.
Adding water to an operating boiler when the water level cannot be seen in the gauge
glass tube.
, Which of the following is best if a low-pressure boiler does not have an air vent?
A. Vent the boiler with the try cocks.
B. Vent the boiler with the safety valve.
C. Vent the boiler with the fusible plug.
D. Vent the boiler with the blowdown line. -CORRECTANSWER A. Vent the boiler with
the try cocks.
What is the purpose of an evaporation test on a low pressure boiler?
A. To test the water column
B. To test the bottom blowdown valve
C. To test the steam pressure safety valve
D. To test the low water cutoff control. -CORRECTANSWER D. To test the low water
cutoff control.
Following flame failure, controls must de-energize fuel and ignition circuits
A. within 4 seconds.
B. within 6 seconds.
C. within 10 seconds.
D. within 15 seconds. -CORRECTANSWER A. within 4 seconds.
How can an operator prevent damage to the tubes while using a cleaner to remove
scale from boiler tubes?
A. Never use a chemical cleaning procedure.
