Certification Exam Questions And Correct
Answers (Verified Answers) Plus Rationales
2026 Q&A | Instant Download Pdf
1. Which of the following is the main purpose of a boiler fusible
plug?
a) To increase steam pressure
b) To measure water level
c) To prevent overheating of the boiler
d) To control fuel flow
The fusible plug melts if water drops below a safe level, preventing
boiler damage.
2. What is the typical material used for welding low-carbon steel in
boiler construction?
a) Cast iron
b) Mild steel electrodes
c) Stainless steel
d) Copper
Mild steel electrodes are compatible with low-carbon steel and
provide strong welds.
3. Which pressure vessel component is designed to relieve excessive
pressure automatically?
a) Manway
b) Drain valve
, c) Safety valve
d) Handhole
Safety valves prevent catastrophic failure by releasing pressure if it
exceeds limits.
4. When performing nondestructive testing on a weld, which
method uses magnetic fields?
a) Ultrasonic testing
b) Radiographic testing
c) Magnetic particle testing
d) Dye penetrant testing
Magnetic particle testing detects surface and slightly subsurface
discontinuities in ferromagnetic materials.
5. What is the purpose of a boiler’s water level indicator?
a) To measure fuel flow
b) To ensure safe water level for operation
c) To increase steam pressure
d) To remove sediment
Maintaining proper water level prevents overheating and possible
boiler failure.
6. Which fitting is commonly used to connect pipes of different
diameters?
a) Elbow
b) Reducer
c) Tee
d) Coupling
A reducer adjusts the diameter of a pipe to maintain flow and
connection integrity.
, 7. Which type of joint is preferred in high-pressure boiler piping?
a) Threaded
b) Welded
c) Soldered
d) Flanged
Welded joints provide the strength and leak-proof integrity
required for high-pressure applications.
8. What is the primary hazard associated with boiler blowdown?
a) Fuel leakage
b) Electrical shock
c) Scalding from hot water or steam
d) Chemical exposure
Boiler blowdown releases high-temperature water/steam; proper
PPE prevents injury.
9. In pipefitting, what does the term “NPS” stand for?
a) Nominal Pressure System
b) Non-Pressure Steel
c) Nominal Pipe Size
d) National Pipe Standard
NPS defines the standardized diameter of pipes, independent of
wall thickness.
10. Which process is used to remove scale and sediment from a
boiler?
a) Welding
b) Painting
c) Boiler blowdown
d) Annealing