PLUMBING LEVEL 3 EXAM
PLUMBING LEVEL 3 EXAM QUESTIONS AND
ANSWERS WITH COMPLETE SOLUTIONS
GRADED A 2025
A journeyman plumber and an apprentice, who are employed by a master plumber, are
installing the DWV-system and water distribution system in a 2-½ story single family
dwelling. QUESTION: What answer below shall be considered most correct to complete
the following "Plumbing code knowledge" related statement: A trap that serves a single
shower stall that is equipped with a hand shower, a rain head, and a standard shower
head shall be no less than ________ in minimum diameter
A) 1-½" B) 2" C) 2-½" D) 3" -Correct Answer ✔2 inches
A journeyman plumber and apprentice are installing 3-inch floor drains in an open-
parking-garage that is subject to freezing temperatures. QUESTION: What answer
below shall be considered most correct to complete the following "Plumbing code
knowledge" related statement: The installation of traps at the floor drain locations which
are found susceptible to freezing temperatures may be __________.
A)Increased to 4-inch B) Eliminated C) Wrapped with freeze protection cable D)
Insulated -Correct Answer ✔eliminated
A journeyman plumber and apprentice are installing lab sinks with faucets that are
connected to an acid waste system for-(special hazardous waste) in a medical lab.
What answer below shall be considered most correct to complete the following
"Plumbing code knowledge" related statement: Vacuum breakers shall be installed with
the critical level at least _____-inches above the flood level rim of the fixture they serve
and on the discharge side of the last control valve to the fixture.
A) 12 B) 6 C) 18 D) 3 -Correct Answer ✔6 inches
What answer below shall be considered most correct to complete the following
"Plumbing code knowledge" related statement: No plumbing permit shall be issued for
cross connection installations that require ______________ until the application for a
permit is accompanied by a letter of approval from the Massachusetts Department of
Environmental Protection or its designee.
A) RPBP B) A "critical level" height C) Atmospheric vacuum breakers D) Water recycling
systems -Correct Answer ✔reduced pressure backflow preventer (RPBP)
: What answer below shall be considered most correct to complete the following
"Plumbing code knowledge" related statement: The waste discharge from safe waste
pans serving water heaters or hot water storage tanks where there is _______ below
and shall be piped indirectly to a properly trapped and vented fixture.
PLUMBING LEVEL 3 EXAM
,PLUMBING LEVEL 3 EXAM
A) People B) Occupancy C) Floors D) Plumbing connections -Correct Answer
✔occupancy
GIVEN: A journeyman plumber and an apprentice, (who are employed by a master
plumber), are installing the sanitary DWV and water distribution system in a five-story
residential condominium complex. QUESTION: What answer below shall be considered
most correct to complete the following "Plumbing code knowledge" related statement:
CPVC-(Chlorinated Polyvinyl Chloride) pipe and fittings may be used provided that none
of this material is located within ____-inches of any connection to a hot water tank as
defined in MGL. c. 142, § 17
A) 12 B) 18 C) 20 D) 24 E) 30 -Correct Answer ✔24 inches
: A journeyman plumber and apprentice are roughing-in multiple fixtures in a new fitness
center. The facility will include a juice bar, temporary daycare room, men's and women's
toilet facilities and men's and women's locker rooms. QUESTION: What answer below
shall be considered most correct to complete the following "Plumbing code knowledge"
related statement: A ________-vent is a branch vent that serves two or more floor-outlet
fixtures that are battery wasted. The vent extends from the top of the horizontal soil
and/or waste branch in front of the last fixture waste and connects to a vent stack or
stack vent that is adjacent to the down-stream end of the horizontal branch.
A) Side B) Loop C) Relief D) Circuit -Correct Answer ✔loop
MATCH:
Elevated pressure
Flow designation
Ten P.S.I.G. or less
Less than 2-P.S.I
A) 3 P.S.I.G. or ten times
B) Inlet pressure
C) E.H.D.
D) Prof. Engineer -Correct Answer ✔elevated pressure- d
flow designation-c
Ten P.S.I.G. or less-a
Less than 2-P.S.I-b
N: A journeyman plumber is installing category-I gas appliances and equipment in the
basement of a building. A 120,000 BTU/hr. boiler and 40,000 BTU/hr. water heater are
being installed. QUESTION: What answer below shall be considered most correct to
complete the following "Gas code knowledge" related statement: The boiler requires a
minimum of _____-cu. ft. of air to support proper combustion
A) 2,400 cu. ft. B) 120 sq. in. C) 3,200 sq. ft. D) 800 cu. ft. -Correct Answer ✔2,400 cu.
ft. 120,000/50
PLUMBING LEVEL 3 EXAM
, PLUMBING LEVEL 3 EXAM
) QUESTION: What answer below shall be considered most correct to complete the
following "Gas code knowledge" related statement: The code would require the gas vent
penetrating the roof in-[FIGURE-TP-B-Q1-1A: GAS VENT SIZING] as identified at point-
[A] to be not less than ______ above any portion of a building within 10-feet
horizontally.
A) 24" B) 3-feet C) 30-inches D) Forty-two-inches -Correct Answer ✔24
In Massachusetts copper tubing and fittings may be used for natural gas piping
A) Provided that the tubing is type-k with flared fitting connections. B) When approved
by the authority having jurisdiction.
C) At interior locations only and not concealed.
D) If the gas contains no more than .03 grains of hydrogen sulfide per 100 cu. ft. of gas.
-Correct Answer ✔If the gas contains no more than .03 grains of hydrogen sulfide per
100 cu. ft. of gas
: A journeyman plumber and apprentice, who are employed by a master plumber, are
installing a natural gas fired category-1 boiler and water heater to an interior, clay tile
lined, masonry chimney. When measured in compliance with the code the chimney
"height" is 48-feet. QUESTION: What answer below shall be considered most correct to
complete the following "Gas code knowledge" related statement: _____ is the maximum
allowable amount of 6-inch single wall metal vent connector material that may be
installed horizontally to connect the boiler and water heater to the chimney
A) 36-feet B) 50% of the chimney height C) 48-feet D) 9-feet -Correct Answer ✔36 feet
: A journeyman plumber is installing a natural gas fired category-1 boiler with an indirect
water heater. Type-B double wall vent connector material is being used to vent products
of combustion from the boiler to an interior tile lined masonry chimney that is 35-feet in
height. QUESTION: What answer below shall be considered most correct to complete
the following "Gas code knowledge" related statement: A clearance of _____ from
combustibles shall be maintained when using/installing type-B vent materials.
A) 6-inches B) 2" C) 1-foot D) One-inch -Correct Answer ✔one inch
A)1 Fixture unit
B)D 2' X L' X _____= Capacity
C)Diameter ÷ 2
D) .00433A)7.5 GALLONS
A)7.5 GALLONS
B)5.875
C)RADIUS OF A CIRCLE
D)1 CU IN OF WATER -Correct Answer ✔A)7.5 GALLONS
B)5.875
PLUMBING LEVEL 3 EXAM
PLUMBING LEVEL 3 EXAM QUESTIONS AND
ANSWERS WITH COMPLETE SOLUTIONS
GRADED A 2025
A journeyman plumber and an apprentice, who are employed by a master plumber, are
installing the DWV-system and water distribution system in a 2-½ story single family
dwelling. QUESTION: What answer below shall be considered most correct to complete
the following "Plumbing code knowledge" related statement: A trap that serves a single
shower stall that is equipped with a hand shower, a rain head, and a standard shower
head shall be no less than ________ in minimum diameter
A) 1-½" B) 2" C) 2-½" D) 3" -Correct Answer ✔2 inches
A journeyman plumber and apprentice are installing 3-inch floor drains in an open-
parking-garage that is subject to freezing temperatures. QUESTION: What answer
below shall be considered most correct to complete the following "Plumbing code
knowledge" related statement: The installation of traps at the floor drain locations which
are found susceptible to freezing temperatures may be __________.
A)Increased to 4-inch B) Eliminated C) Wrapped with freeze protection cable D)
Insulated -Correct Answer ✔eliminated
A journeyman plumber and apprentice are installing lab sinks with faucets that are
connected to an acid waste system for-(special hazardous waste) in a medical lab.
What answer below shall be considered most correct to complete the following
"Plumbing code knowledge" related statement: Vacuum breakers shall be installed with
the critical level at least _____-inches above the flood level rim of the fixture they serve
and on the discharge side of the last control valve to the fixture.
A) 12 B) 6 C) 18 D) 3 -Correct Answer ✔6 inches
What answer below shall be considered most correct to complete the following
"Plumbing code knowledge" related statement: No plumbing permit shall be issued for
cross connection installations that require ______________ until the application for a
permit is accompanied by a letter of approval from the Massachusetts Department of
Environmental Protection or its designee.
A) RPBP B) A "critical level" height C) Atmospheric vacuum breakers D) Water recycling
systems -Correct Answer ✔reduced pressure backflow preventer (RPBP)
: What answer below shall be considered most correct to complete the following
"Plumbing code knowledge" related statement: The waste discharge from safe waste
pans serving water heaters or hot water storage tanks where there is _______ below
and shall be piped indirectly to a properly trapped and vented fixture.
PLUMBING LEVEL 3 EXAM
,PLUMBING LEVEL 3 EXAM
A) People B) Occupancy C) Floors D) Plumbing connections -Correct Answer
✔occupancy
GIVEN: A journeyman plumber and an apprentice, (who are employed by a master
plumber), are installing the sanitary DWV and water distribution system in a five-story
residential condominium complex. QUESTION: What answer below shall be considered
most correct to complete the following "Plumbing code knowledge" related statement:
CPVC-(Chlorinated Polyvinyl Chloride) pipe and fittings may be used provided that none
of this material is located within ____-inches of any connection to a hot water tank as
defined in MGL. c. 142, § 17
A) 12 B) 18 C) 20 D) 24 E) 30 -Correct Answer ✔24 inches
: A journeyman plumber and apprentice are roughing-in multiple fixtures in a new fitness
center. The facility will include a juice bar, temporary daycare room, men's and women's
toilet facilities and men's and women's locker rooms. QUESTION: What answer below
shall be considered most correct to complete the following "Plumbing code knowledge"
related statement: A ________-vent is a branch vent that serves two or more floor-outlet
fixtures that are battery wasted. The vent extends from the top of the horizontal soil
and/or waste branch in front of the last fixture waste and connects to a vent stack or
stack vent that is adjacent to the down-stream end of the horizontal branch.
A) Side B) Loop C) Relief D) Circuit -Correct Answer ✔loop
MATCH:
Elevated pressure
Flow designation
Ten P.S.I.G. or less
Less than 2-P.S.I
A) 3 P.S.I.G. or ten times
B) Inlet pressure
C) E.H.D.
D) Prof. Engineer -Correct Answer ✔elevated pressure- d
flow designation-c
Ten P.S.I.G. or less-a
Less than 2-P.S.I-b
N: A journeyman plumber is installing category-I gas appliances and equipment in the
basement of a building. A 120,000 BTU/hr. boiler and 40,000 BTU/hr. water heater are
being installed. QUESTION: What answer below shall be considered most correct to
complete the following "Gas code knowledge" related statement: The boiler requires a
minimum of _____-cu. ft. of air to support proper combustion
A) 2,400 cu. ft. B) 120 sq. in. C) 3,200 sq. ft. D) 800 cu. ft. -Correct Answer ✔2,400 cu.
ft. 120,000/50
PLUMBING LEVEL 3 EXAM
, PLUMBING LEVEL 3 EXAM
) QUESTION: What answer below shall be considered most correct to complete the
following "Gas code knowledge" related statement: The code would require the gas vent
penetrating the roof in-[FIGURE-TP-B-Q1-1A: GAS VENT SIZING] as identified at point-
[A] to be not less than ______ above any portion of a building within 10-feet
horizontally.
A) 24" B) 3-feet C) 30-inches D) Forty-two-inches -Correct Answer ✔24
In Massachusetts copper tubing and fittings may be used for natural gas piping
A) Provided that the tubing is type-k with flared fitting connections. B) When approved
by the authority having jurisdiction.
C) At interior locations only and not concealed.
D) If the gas contains no more than .03 grains of hydrogen sulfide per 100 cu. ft. of gas.
-Correct Answer ✔If the gas contains no more than .03 grains of hydrogen sulfide per
100 cu. ft. of gas
: A journeyman plumber and apprentice, who are employed by a master plumber, are
installing a natural gas fired category-1 boiler and water heater to an interior, clay tile
lined, masonry chimney. When measured in compliance with the code the chimney
"height" is 48-feet. QUESTION: What answer below shall be considered most correct to
complete the following "Gas code knowledge" related statement: _____ is the maximum
allowable amount of 6-inch single wall metal vent connector material that may be
installed horizontally to connect the boiler and water heater to the chimney
A) 36-feet B) 50% of the chimney height C) 48-feet D) 9-feet -Correct Answer ✔36 feet
: A journeyman plumber is installing a natural gas fired category-1 boiler with an indirect
water heater. Type-B double wall vent connector material is being used to vent products
of combustion from the boiler to an interior tile lined masonry chimney that is 35-feet in
height. QUESTION: What answer below shall be considered most correct to complete
the following "Gas code knowledge" related statement: A clearance of _____ from
combustibles shall be maintained when using/installing type-B vent materials.
A) 6-inches B) 2" C) 1-foot D) One-inch -Correct Answer ✔one inch
A)1 Fixture unit
B)D 2' X L' X _____= Capacity
C)Diameter ÷ 2
D) .00433A)7.5 GALLONS
A)7.5 GALLONS
B)5.875
C)RADIUS OF A CIRCLE
D)1 CU IN OF WATER -Correct Answer ✔A)7.5 GALLONS
B)5.875
PLUMBING LEVEL 3 EXAM
