Maryland Stationary Engineer Practice Test Questions with Verified Answers (2026 Updated)

,Maryland Stationary Engineer Practice Test 2026 |
Most Tested Questions | Graded A+

How much clearance from the top of the boiler is needed for a HP boiler that produces
70000 lbs of steam? - correct ans7 feet

On a gas fired boiler what is the proper gas to air mixture - correct ans30%-70% and in
special arrangements it can be as high as 100% . ANSWER CHAPTER 11 remember%

What is the total hardness in a system that was found to have calcium hardness of
60ppm and magnesium hardness of 18ppm and carbon hardness of 12 ppm? - correct
ansTH=(Ca x 2.5) + (Mg x 4.1)\nTH=(60 x 2.5) + (18 x 4.1)\nTH= 150+73.8 =( 223.8
PPM)

How often should a complete external inspection of the boiler be done? - correct
ansOnce a Shift

With 24 hr operation how often do you check the water level? - correct ansOnce per
shift

How often do you check the LWCO? - correct ansOnce per shift

How often do you check the High Limit Switch? - correct ansAnnually

A 2" pipe was found to be delivering water at 100 psia at 1040ft per second. How many
gallons per hour will it deliver? - correct ansGPM= V (diameter squared) divided by
.4085 ANSWER pg 469 BOG

What controls the amount of blowback on a safety valve? - correct ansBlowback ring or
adjusting ring

On a open air expansion tank hot water boiler system; how high should it be mounted? -
correct ans(4 Feet ) above the highest heating element.

What is the minimum top clearance of boilers with manholes? - correct ans5 feet

Package boilers; steam heating boilers and hot water heating boilers shall have a
minimum clearance of? - correct ans2 feet from ceiling. Code chapter 10 page76

Most important safety device on a boiler? - correct ansSafety relief valve

What does a Black Liquor Boiler do? - correct ansBlack Liquor is the by product of wood
pulp processing in the paper making industry.

,What does Black liquor boiler known for? - correct ansSteam generation and recovery
of soda ash

Maximum line voltage for control on a boiler? - correct ans150 volts

Under what code are boilers designed and constructed? - correct ansASME- CSD 1

How many low water cut offs are needed per code for a hot water system when a boiler
has inputs greater than 400,000 btu per hr - correct ans1 LWCO is needed.

What is the minimum and maximum size for a safety valve per code for boilers? -
correct ansMinimum 3/4" and Maximum 4 1/2"

What stamp is put on a boiler after repairs? - correct ans"R"

What is the equalizing system used for? - correct ansThe equalizing system is for
warming up the steam lead.

A blowdown valve is located at the lowest water space of a boiler for three purposes -
correct ans1. to remove precipitated sludge or loose scale \n2. To permit rapid lowering
of the boiler water if it has become too high accidentally \n3. As a means of removing
water from the boiler so that fresh water may be added to keep the concentration of
solids below the point where difficulties may be experienced.

In the old power boiler which type of feed-water regulators were not used? - correct
ansElectronic

After opening a boiler for repairs how much oxygen is needed? - correct ans19%

What is the first thing you do when shutting down a boiler? - correct ansTurn off
(extinguish fire)

What is the legal limit of acceptable asbestos particles ? - correct ans0.1 fibers per
cubic centimeter

What is CREEP? - correct ansCreep is defined as the slow deformation of material with
time; with the deformation taking place at elevated temperatures with no increase in
stress.

What is the BTU content of Anthracite coal? - correct ans14000 btu/lb

What substance transfers electrical current in a photocell? - correct ansElectricity will
flow when the CADMIUM is exposed to sufficient light.

, What device acts as a check valve in both directions and keeps pumps primed?
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- correct ansFOOT VALVES are used for pumps under suction pressure to
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prevent backflow primed? on the suction line.
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What protects boilers from explosion in the furnace? - correct ansA flame guard system
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is an arrangement of flame detection system; interlocks; and relays which will sense the
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presence of a proper flame in a furnace and cause fuel to be shut off to the furnace if
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a hazardous condition develops (improper flame or combustion).
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What size pipe is used as a header in a boiler operating at 100psi? - correct ans6
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inches
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What device is used to measure flue gasses - correct ansThe Orsat Analyzer
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Which low water cut off does not have a mercury switch? - correct ansThe Submerged
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electrode type
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What is the btu output per lb of #4 fuel oil? - correct ans18
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What substance is used for the electric transmission in an RTD? - correct ansPlatinum
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is used because of its stability at high temperatures
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How much air is needed for the combustion of pulverized coal; gas; oil? - correct
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ans50% for coal and 10-30% for gas & oil
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In old power boilers which type of feedwater regulators were not used? \n(A) hydraulic
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\n(B) float \n(C) thermostatic expansion \n(D) electronic - correct ansANSWER D
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electronic/electro-magnetic
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What is hard forming scale? - correct ansSilica
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With hydroxide present and normal oxygen levels which chemical will cause problems?
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- correct ansChlorine
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The result from steel manufacturing and under pressure in boilers tends to cause
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buldging? A buldge is caused by ? - correct ansA buldge is caused by overheating of
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the shell plates and it affects the entire thickness of the plate.
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A blister is caused by what ? - correct ansSlag inclusion forming a lamination at the time
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the plate was rolled at the steel mill. A blister is a separation of the metal from the
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shell plate caused by impurities rolled into the shell plate when formed.
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With normal oxygen and low alkalinity. what is added to the boiler water? - correct
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ansNeutralizing Amines
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