Ohio Boiler Operator Exam Practice
Questions And Correct Answers
(Verified Answers) Plus Rationales
2025|2026 Q&A | Instant Download Pdf
1. What is the primary purpose of a boiler?
a) To cool water
b) To generate steam
c) To store water
d) To heat air
Steam is the useful output of a boiler, generated by heating water.
2. What pressure defines a high-pressure boiler in Ohio?
a) Above 10 psig
b) Above 15 psig steam or 160 psig hot water
c) Above 15 psig steam or 160 psig hot water
d) Above 50 psig
Ohio defines high-pressure boilers at more than 15 psig steam or 160
psig hot water.
,3. The safety valve on a boiler prevents:
a) Corrosion
b) Scaling
c) Overpressure
d) Water carryover
Safety valves automatically release steam to prevent dangerous
pressure rise.
4. The low-water cutoff protects against:
a) Overheating of water
b) Overheating of boiler metal
c) Loss of efficiency
d) Excessive pressure
Without water, boiler tubes overheat and can rupture.
5. What is boiler blowdown used for?
a) Cooling feedwater
b) Removing sediment and dissolved solids
c) Reducing steam pressure
d) Lowering pH
Blowdown controls solids to prevent scale and corrosion.
6. Boiler efficiency is the ratio of:
a) Steam pressure to heat input
b) Water to fuel
c) Heat absorbed by water to heat supplied by fuel
, d) Steam temperature to fuel temperature
Efficiency measures how much fuel energy transfers to water/steam.
7. What type of boiler is most common in large power plants?
a) Fire-tube
b) Water-tube
c) Electric
d) Cast iron sectional
Water-tube boilers handle high pressure and large capacity.
8. In a fire-tube boiler, the hot gases:
a) Surround water-filled tubes
b) Pass through tubes surrounded by water
c) Flow outside the boiler shell
d) Never contact tubes
Fire-tube design has hot gas inside tubes with water around them.
9. In a water-tube boiler, the water:
a) Surrounds hot gas tubes
b) Flows inside tubes heated externally by hot gases
c) Is only in the drum
d) Is used only in condensers
Water-tube design carries water inside tubes heated by furnace
gases.
10. Which chemical is commonly used for oxygen scavenging in
boilers?
Questions And Correct Answers
(Verified Answers) Plus Rationales
2025|2026 Q&A | Instant Download Pdf
1. What is the primary purpose of a boiler?
a) To cool water
b) To generate steam
c) To store water
d) To heat air
Steam is the useful output of a boiler, generated by heating water.
2. What pressure defines a high-pressure boiler in Ohio?
a) Above 10 psig
b) Above 15 psig steam or 160 psig hot water
c) Above 15 psig steam or 160 psig hot water
d) Above 50 psig
Ohio defines high-pressure boilers at more than 15 psig steam or 160
psig hot water.
,3. The safety valve on a boiler prevents:
a) Corrosion
b) Scaling
c) Overpressure
d) Water carryover
Safety valves automatically release steam to prevent dangerous
pressure rise.
4. The low-water cutoff protects against:
a) Overheating of water
b) Overheating of boiler metal
c) Loss of efficiency
d) Excessive pressure
Without water, boiler tubes overheat and can rupture.
5. What is boiler blowdown used for?
a) Cooling feedwater
b) Removing sediment and dissolved solids
c) Reducing steam pressure
d) Lowering pH
Blowdown controls solids to prevent scale and corrosion.
6. Boiler efficiency is the ratio of:
a) Steam pressure to heat input
b) Water to fuel
c) Heat absorbed by water to heat supplied by fuel
, d) Steam temperature to fuel temperature
Efficiency measures how much fuel energy transfers to water/steam.
7. What type of boiler is most common in large power plants?
a) Fire-tube
b) Water-tube
c) Electric
d) Cast iron sectional
Water-tube boilers handle high pressure and large capacity.
8. In a fire-tube boiler, the hot gases:
a) Surround water-filled tubes
b) Pass through tubes surrounded by water
c) Flow outside the boiler shell
d) Never contact tubes
Fire-tube design has hot gas inside tubes with water around them.
9. In a water-tube boiler, the water:
a) Surrounds hot gas tubes
b) Flows inside tubes heated externally by hot gases
c) Is only in the drum
d) Is used only in condensers
Water-tube design carries water inside tubes heated by furnace
gases.
10. Which chemical is commonly used for oxygen scavenging in
boilers?
