Boiler Operator Licensing Exam 2026
Questions and Answers
1 or more safety valves - Correct answer-all steam boilers must have
Locked closed - Correct answer-before anyone enters the boiler drum, the main
steam stop valve, bottom blowdown valves, & feedwater valves should be
212 degrees F - Correct answer-at atmospheric pressure, water begins to boil at
approximately
Fuel oil, gas, & coal - Correct answer-fuels most commonly used in boilers
Steam pressure gauge - Correct answer-must be connected to the highest part of the
steam side of the boiler
Half full - Correct answer-with an NOWL in a boiler, the gauge glass is
approximately
Foaming - Correct answer-a high surface tension on top of the boiler water can
lead to
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, Mud drum - Correct answer-Bottom blowdown on a boiler removes sludge &
sediment from the
Tin - Correct answer-a boiler fusible plug is brass or bronze with a core of
Pounds per square inch - Correct answer-a steam pressure gauge is calibrated in
Try cocks - Correct answer-a secondary means of determining boiler water level
Oily waste rag storage - Correct answer-fires caused by spontaneous combustion
are most likely to occur in the
Steam - Correct answer-a siphon installed between the boiler & the pressure gauge
protects the Bourdon tube from
Prevent formation of scale - Correct answer-boiler feedwater is chemically treated
to
Inside tube surface - Correct answer-in a firetube boiler, soot accumulates on the
1.5 times the MAWP - Correct answer-the pressure applied on the boiler during a
hydrostatic test should be
Decreased - Correct answer-as fuel oil is heated, its viscosity is
Chimney - Correct answer-the induced draft fan is located between the boiler & the
©COPYRIGHT 2025, ALL RIGHTS RESERVED 2
Questions and Answers
1 or more safety valves - Correct answer-all steam boilers must have
Locked closed - Correct answer-before anyone enters the boiler drum, the main
steam stop valve, bottom blowdown valves, & feedwater valves should be
212 degrees F - Correct answer-at atmospheric pressure, water begins to boil at
approximately
Fuel oil, gas, & coal - Correct answer-fuels most commonly used in boilers
Steam pressure gauge - Correct answer-must be connected to the highest part of the
steam side of the boiler
Half full - Correct answer-with an NOWL in a boiler, the gauge glass is
approximately
Foaming - Correct answer-a high surface tension on top of the boiler water can
lead to
©COPYRIGHT 2025, ALL RIGHTS RESERVED 1
, Mud drum - Correct answer-Bottom blowdown on a boiler removes sludge &
sediment from the
Tin - Correct answer-a boiler fusible plug is brass or bronze with a core of
Pounds per square inch - Correct answer-a steam pressure gauge is calibrated in
Try cocks - Correct answer-a secondary means of determining boiler water level
Oily waste rag storage - Correct answer-fires caused by spontaneous combustion
are most likely to occur in the
Steam - Correct answer-a siphon installed between the boiler & the pressure gauge
protects the Bourdon tube from
Prevent formation of scale - Correct answer-boiler feedwater is chemically treated
to
Inside tube surface - Correct answer-in a firetube boiler, soot accumulates on the
1.5 times the MAWP - Correct answer-the pressure applied on the boiler during a
hydrostatic test should be
Decreased - Correct answer-as fuel oil is heated, its viscosity is
Chimney - Correct answer-the induced draft fan is located between the boiler & the
©COPYRIGHT 2025, ALL RIGHTS RESERVED 2
