CLASS 5 BOILER EXAM 2025/2026 QUESTIONS WITH
ANSWERS GRADED A+
✔✔T/F All automatically fired boilers from 12,500,000 btu or less are subected to ASME
CSD.1 - ✔✔True
✔✔Doubling the size of pipe increases the capacity by how many times? - ✔✔Four
✔✔Max amount of weld undercut allowed by ASME B31.1 - ✔✔1/32"
✔✔T/F Slip on flanges welded inside and out on category M - ✔✔True
✔✔Blueprint solid line with arrows is a _________ line - ✔✔Dimension
✔✔Is PVC allowed in compressed air systems? - ✔✔No
✔✔Flanges installed on steam piping systems must: - ✔✔Be stamped with the
manufactures name and ASME B.16.5 and class number.
✔✔T/F Pneumatic pressure test of regulated piping systems must be Chief boiler
inspector. - ✔✔True
✔✔ASME code governing power boilers? - ✔✔Section 1
✔✔T/F Seal welds may be used to avoid leakage on B31.5 should not be considered as
contributing strength - ✔✔True
✔✔T/F When installing a domestic H2O supply boiler the following info is on the boiler
data plate, H160psi, 240F, this unit is exempt from CSD-1 - ✔✔False
✔✔T/F Backing is the use of material or a device placed against the backside of a joint
to support and retain molten weld metal. - ✔✔True
✔✔ORS.480.634 says licensed journeyman plumbers can install hot H20 boilers if: -
✔✔less than 750k btu, up to 180 gal, and max 150psi
✔✔Combination temperature and pressure relief valves are used on direct fired hot
water supply boilers in order to: - ✔✔keep water temp. below 210 and relieve at the set
pressure of the safety valve.
✔✔t/f Stress relieving is a form of heat treatment - ✔✔True
, ✔✔What section of ASME boiler and pressure vessel code sets rules for braising
process and performance standards? - ✔✔IX
✔✔What part of ASME code regulates controls in automatically fired boilers? - ✔✔CSD-
1
✔✔Amount of weld reinforcement is determined by _________. - ✔✔Thickness
✔✔t/f State or insurance boiler inspector must be informed prior to starting work. -
✔✔True
✔✔t/f It is permissible to place a temporary plug in discharge opening of safety relief
valve - ✔✔True
✔✔Adding a pipe branch connection by welding is allowed providing __________ is
performed. - ✔✔reinforcement
✔✔t/f ASME B31.9 allows the use of plastic piping for building services piping. -
✔✔False
✔✔t/f All cast iron boilers shall be provided with a wash out opening which is not smaller
than 1 1/2 nps - ✔✔False
✔✔Which non destructive examination method best reveals lack of fusion in a finished
weld? - ✔✔Radiography
✔✔Steam boilers operated at 10 psig are required to be constructed under which ASME
code? - ✔✔Section IV
✔✔Hot H2O heating and hot H2O supply boilers must be tested at a pressure of -
✔✔1.5 mawp
✔✔Which of the following provides information required to make sound welds for ASME
service? - ✔✔the engineered working drawings or PQR
✔✔Heat numbers are to be transferred ________ to cutting any material. - ✔✔Prior
✔✔Before entering a boiler or pressure vessel: - ✔✔company confined space
procedures are followed.
✔✔t/f Ammonia piping installation falls under the state boiler safety program. - ✔✔False
ANSWERS GRADED A+
✔✔T/F All automatically fired boilers from 12,500,000 btu or less are subected to ASME
CSD.1 - ✔✔True
✔✔Doubling the size of pipe increases the capacity by how many times? - ✔✔Four
✔✔Max amount of weld undercut allowed by ASME B31.1 - ✔✔1/32"
✔✔T/F Slip on flanges welded inside and out on category M - ✔✔True
✔✔Blueprint solid line with arrows is a _________ line - ✔✔Dimension
✔✔Is PVC allowed in compressed air systems? - ✔✔No
✔✔Flanges installed on steam piping systems must: - ✔✔Be stamped with the
manufactures name and ASME B.16.5 and class number.
✔✔T/F Pneumatic pressure test of regulated piping systems must be Chief boiler
inspector. - ✔✔True
✔✔ASME code governing power boilers? - ✔✔Section 1
✔✔T/F Seal welds may be used to avoid leakage on B31.5 should not be considered as
contributing strength - ✔✔True
✔✔T/F When installing a domestic H2O supply boiler the following info is on the boiler
data plate, H160psi, 240F, this unit is exempt from CSD-1 - ✔✔False
✔✔T/F Backing is the use of material or a device placed against the backside of a joint
to support and retain molten weld metal. - ✔✔True
✔✔ORS.480.634 says licensed journeyman plumbers can install hot H20 boilers if: -
✔✔less than 750k btu, up to 180 gal, and max 150psi
✔✔Combination temperature and pressure relief valves are used on direct fired hot
water supply boilers in order to: - ✔✔keep water temp. below 210 and relieve at the set
pressure of the safety valve.
✔✔t/f Stress relieving is a form of heat treatment - ✔✔True
, ✔✔What section of ASME boiler and pressure vessel code sets rules for braising
process and performance standards? - ✔✔IX
✔✔What part of ASME code regulates controls in automatically fired boilers? - ✔✔CSD-
1
✔✔Amount of weld reinforcement is determined by _________. - ✔✔Thickness
✔✔t/f State or insurance boiler inspector must be informed prior to starting work. -
✔✔True
✔✔t/f It is permissible to place a temporary plug in discharge opening of safety relief
valve - ✔✔True
✔✔Adding a pipe branch connection by welding is allowed providing __________ is
performed. - ✔✔reinforcement
✔✔t/f ASME B31.9 allows the use of plastic piping for building services piping. -
✔✔False
✔✔t/f All cast iron boilers shall be provided with a wash out opening which is not smaller
than 1 1/2 nps - ✔✔False
✔✔Which non destructive examination method best reveals lack of fusion in a finished
weld? - ✔✔Radiography
✔✔Steam boilers operated at 10 psig are required to be constructed under which ASME
code? - ✔✔Section IV
✔✔Hot H2O heating and hot H2O supply boilers must be tested at a pressure of -
✔✔1.5 mawp
✔✔Which of the following provides information required to make sound welds for ASME
service? - ✔✔the engineered working drawings or PQR
✔✔Heat numbers are to be transferred ________ to cutting any material. - ✔✔Prior
✔✔Before entering a boiler or pressure vessel: - ✔✔company confined space
procedures are followed.
✔✔t/f Ammonia piping installation falls under the state boiler safety program. - ✔✔False
