Master Plumbing WSSC Exam Questions
With All Correct Answers 2025 Latest
Update
Waste water discharged into the building drainage system shall not be over _______ *F
CORRECT ANSWERS 140
A water tank holds 50 gallons of water. How much does the 50 gallons of water weigh?
CORRECT ANSWERS 417 lbs
Exterior walls may be notched to a depth exceeding _______________ percent of its
width. CORRECT ANSWERS 25
According to the WSSC PFGC, a full flow building water service valve shall be installed
within _____ feet of where the water service enters the building. CORRECT ANSWERS
3'
According to the WSSC PFGC, water meters installed inside of buildings shall be
located in an area capable of maintaining _____ *F. CORRECT ANSWERS 50
In Prince George and Montgomery County, water service piping shall be not less than
_____ inches below grade. CORRECT ANSWERS 30
A cylindrical tank is 22 inches in diameter and 5 feet tall. How many gallons of water will
it hold? CORRECT ANSWERS 98
The best method of backflow protection is an? CORRECT ANSWERS Air-gap
Horizontal drainage piping 4 inches in diameter shall have a minimum slope of _____
per foot. CORRECT ANSWERS 1/8
Water hammer arrestors shall conform to ASSE _______ CORRECT ANSWERS 1010
A connection between a vent pipe and a vent stack or stack vent shall be at least _____
inches above the flood level rim of the highest fixture served by the vent. CORRECT
ANSWERS 6 inches
Air admittance valves shall be installed a minimum of ______ inches above insulation
materials. CORRECT ANSWERS 6
A water supply system test done with air shall be at not less than ____ PSI. CORRECT
ANSWERS 50
, If you install 80 feet of sewer at 1/4" per foot how many inches of fall in the run?
CORRECT ANSWERS 20
The minimum size water supply pipe to a bidet shall be _____ inch. CORRECT
ANSWERS 3/8
Horizontal drains shall have cleanouts not more than ______ feet apart. CORRECT
ANSWERS 100
Standpipes shall extend a maximum of ____ inches above the trap weir. CORRECT
ANSWERS 42
Shower compartments shall not be less than _____ inches in minimum dimension.
CORRECT ANSWERS 30
Shower liners shall be sloped at _____ towards the drain. CORRECT ANSWERS 2.0%
A water closet shall have not less than ____ inches from its centerline to any side wall.
CORRECT ANSWERS 15"
Which of the following tools would cut 20 year old CPVC the best? CORRECT
ANSWERS hacksaw
Which of the following people is ultimately responsible for making sure permits are on
the job? CORRECT ANSWERS master plumber
Which of the following is best defines as a plumbing system that performs in
accordance with the intent of chapters 3-12 of the IPC? CORRECT ANSWERS
alternative engineered design
Which of the following best defines the combination of fixtures consisting of a water
closet, lavatory and bathtub of shower? CORRECT ANSWERS bathroom group
Which one of the following definitions best refers to that part of the drainage system that
extends from the end of the building drain and conveys the discharge to a public sewer?
CORRECT ANSWERS Building sewer
When preparing to work in a large underground meter vault, which one of the following
principles should be given priority? CORRECT ANSWERS confined space entry
If a serious accident occurs on your jobsite that causes another person to become
unconscious and not breathing, you should be prepared to ____________ immediately.
CORRECT ANSWERS administer CPR
When performing any significant excavation activity, it is most important to assure that
which of the following is present on site? CORRECT ANSWERS competent person
With All Correct Answers 2025 Latest
Update
Waste water discharged into the building drainage system shall not be over _______ *F
CORRECT ANSWERS 140
A water tank holds 50 gallons of water. How much does the 50 gallons of water weigh?
CORRECT ANSWERS 417 lbs
Exterior walls may be notched to a depth exceeding _______________ percent of its
width. CORRECT ANSWERS 25
According to the WSSC PFGC, a full flow building water service valve shall be installed
within _____ feet of where the water service enters the building. CORRECT ANSWERS
3'
According to the WSSC PFGC, water meters installed inside of buildings shall be
located in an area capable of maintaining _____ *F. CORRECT ANSWERS 50
In Prince George and Montgomery County, water service piping shall be not less than
_____ inches below grade. CORRECT ANSWERS 30
A cylindrical tank is 22 inches in diameter and 5 feet tall. How many gallons of water will
it hold? CORRECT ANSWERS 98
The best method of backflow protection is an? CORRECT ANSWERS Air-gap
Horizontal drainage piping 4 inches in diameter shall have a minimum slope of _____
per foot. CORRECT ANSWERS 1/8
Water hammer arrestors shall conform to ASSE _______ CORRECT ANSWERS 1010
A connection between a vent pipe and a vent stack or stack vent shall be at least _____
inches above the flood level rim of the highest fixture served by the vent. CORRECT
ANSWERS 6 inches
Air admittance valves shall be installed a minimum of ______ inches above insulation
materials. CORRECT ANSWERS 6
A water supply system test done with air shall be at not less than ____ PSI. CORRECT
ANSWERS 50
, If you install 80 feet of sewer at 1/4" per foot how many inches of fall in the run?
CORRECT ANSWERS 20
The minimum size water supply pipe to a bidet shall be _____ inch. CORRECT
ANSWERS 3/8
Horizontal drains shall have cleanouts not more than ______ feet apart. CORRECT
ANSWERS 100
Standpipes shall extend a maximum of ____ inches above the trap weir. CORRECT
ANSWERS 42
Shower compartments shall not be less than _____ inches in minimum dimension.
CORRECT ANSWERS 30
Shower liners shall be sloped at _____ towards the drain. CORRECT ANSWERS 2.0%
A water closet shall have not less than ____ inches from its centerline to any side wall.
CORRECT ANSWERS 15"
Which of the following tools would cut 20 year old CPVC the best? CORRECT
ANSWERS hacksaw
Which of the following people is ultimately responsible for making sure permits are on
the job? CORRECT ANSWERS master plumber
Which of the following is best defines as a plumbing system that performs in
accordance with the intent of chapters 3-12 of the IPC? CORRECT ANSWERS
alternative engineered design
Which of the following best defines the combination of fixtures consisting of a water
closet, lavatory and bathtub of shower? CORRECT ANSWERS bathroom group
Which one of the following definitions best refers to that part of the drainage system that
extends from the end of the building drain and conveys the discharge to a public sewer?
CORRECT ANSWERS Building sewer
When preparing to work in a large underground meter vault, which one of the following
principles should be given priority? CORRECT ANSWERS confined space entry
If a serious accident occurs on your jobsite that causes another person to become
unconscious and not breathing, you should be prepared to ____________ immediately.
CORRECT ANSWERS administer CPR
When performing any significant excavation activity, it is most important to assure that
which of the following is present on site? CORRECT ANSWERS competent person
