Tennessee (TN) LLP Limited Licensed Plumber Practice Exam
1. What is the primary purpose of plumbing mathematics in the context of plumbing systems?
A) To calculate water usage
B) To determine the number of fixtures needed
C) To ensure proper sizing of pipes and fittings
D) To assess the structural integrity of plumbing installations
Explanation: Plumbing mathematics is mainly used to ensure the proper sizing of pipes and fittings
based on factors like flow rate and pressure.
2. Which of the following symbols is commonly used to represent a water meter on plumbing
blueprints?
A) Square box
B) Circle with a line through it
C) Triangle
D) Circle with the letter "M"
Explanation: A circle with the letter "M" is typically used to represent a water meter on plumbing plans.
3. When interpreting plumbing plans, what is the purpose of the abbreviation "DWV"?
A) Drainage, Waste, and Vent
B) Domestic Water Vent
C) Domestic Water Valve
D) Drainage, Water, and Ventilation
Explanation: "DWV" stands for Drainage, Waste, and Vent, which are critical components of a plumbing
system for waste removal.
4. What is the standard formula for calculating the water supply rate needed for a plumbing system?
A) Pressure x Diameter
B) Flow rate x Pipe length
C) Pipe size x Pressure
D) Fixture units x Pressure
Explanation: The water supply rate is generally calculated using fixture units and pressure, as this
impacts the overall water flow.
5. Which of the following terms refers to a type of joint that connects two pieces of pipe without using
heat or solvents?
A) Flanged joint
B) Push-fit joint
C) Soldered joint
D) Welded joint
,Explanation: A push-fit joint is a type of connection where no heat or solvents are required.
6. When installing backflow prevention devices, which of the following is the most common method
used to prevent contamination of potable water?
A) Air gap
B) Pressure relief valve
C) Check valve
D) Vacuum breaker
Explanation: The air gap is the most common method to prevent backflow by ensuring a physical
separation between potable water and potential contaminants.
7. Which plumbing material is commonly used for water supply pipes due to its corrosion resistance?
A) Cast iron
B) Galvanized steel
C) Copper
D) PVC
Explanation: Copper is widely used for water supply pipes because it resists corrosion and is durable
under pressure.
8. In plumbing, what does the term "head" refer to?
A) The pressure exerted by water in the system
B) The length of a pipe
C) The material of a pipe
D) The temperature of the water
Explanation: "Head" refers to the pressure exerted by water in a plumbing system due to gravity or
pump action.
9. What is the primary purpose of storm drainage systems in a plumbing design?
A) To direct water to a sewage treatment plant
B) To prevent flooding by directing excess rainwater away from structures
C) To store water for future use
D) To filter rainwater for potable use
Explanation: Storm drainage systems are designed to prevent flooding by efficiently directing excess
rainwater away from buildings and roads.
10. What is the most common type of material used for residential plumbing drain systems?
A) PVC
B) Copper
C) PEX
D) Galvanized steel
,Explanation: PVC is commonly used for drain systems due to its affordability, ease of installation, and
resistance to corrosion.
11. What administrative requirement must be completed before plumbing work can begin on a
construction site?
A) All plumbing fixtures must be ordered
B) A plumbing permit must be obtained
C) Plumbing plans must be drawn by an architect
D) All pipes must be pressure tested
Explanation: A plumbing permit must be obtained before work can begin on any plumbing installation,
as per local building codes.
12. What is the purpose of a plumbing test in new construction?
A) To check for leaks
B) To measure water flow rate
C) To ensure all pipes are correctly sized
D) To test the durability of fixtures
Explanation: A plumbing test is primarily used to check for leaks and ensure the system is sealed
correctly before use.
13. What is a common type of connection used to join copper pipes together in plumbing systems?
A) Compression fitting
B) Push-fit fitting
C) Soldered joint
D) Threaded connection
Explanation: Copper pipes are often joined using soldered joints, where a filler material is melted to seal
the connection.
14. In plumbing, what is the term for the system used to remove wastewater from a building?
A) Venting system
B) Storm drainage system
C) Waste and vent system
D) Drainage system
Explanation: The drainage system is responsible for removing wastewater from a building to the sewer
or septic system.
15. Which of the following plumbing symbols represents a toilet on blueprints?
A) A triangle with a "T"
B) A square with a "W"
C) A circle with two lines through it
D) A square with a "T" inside
, Explanation: A toilet is often represented by a square with a "T" inside it in plumbing blueprints.
16. What is the role of a pressure-reducing valve in a plumbing system?
A) To increase water pressure
B) To prevent backflow
C) To reduce water pressure to safe levels
D) To filter the water supply
Explanation: A pressure-reducing valve helps maintain safe water pressure levels, preventing damage to
the plumbing system.
17. Which of the following materials is most commonly used for drain, waste, and vent (DWV)
systems?
A) Cast iron
B) PEX
C) Copper
D) PVC
Explanation: PVC is most commonly used for DWV systems due to its low cost and ease of installation.
18. What does the term "backflow" refer to in plumbing systems?
A) The normal flow of water through pipes
B) The reverse flow of water into the potable water supply
C) The movement of waste through drain pipes
D) The filtration of water in a system
Explanation: Backflow occurs when water flows in the opposite direction, potentially contaminating the
clean water supply.
19. What is the primary function of a sump pump in a plumbing system?
A) To regulate water pressure
B) To remove excess water from a basement or crawlspace
C) To purify the water supply
D) To increase water flow to fixtures
Explanation: A sump pump is used to remove excess water, often from basements or crawl spaces,
preventing flooding.
20. What material is commonly used for the installation of exterior water lines due to its resistance to
freezing?
A) Cast iron
B) PVC
C) Copper
D) PEX
1. What is the primary purpose of plumbing mathematics in the context of plumbing systems?
A) To calculate water usage
B) To determine the number of fixtures needed
C) To ensure proper sizing of pipes and fittings
D) To assess the structural integrity of plumbing installations
Explanation: Plumbing mathematics is mainly used to ensure the proper sizing of pipes and fittings
based on factors like flow rate and pressure.
2. Which of the following symbols is commonly used to represent a water meter on plumbing
blueprints?
A) Square box
B) Circle with a line through it
C) Triangle
D) Circle with the letter "M"
Explanation: A circle with the letter "M" is typically used to represent a water meter on plumbing plans.
3. When interpreting plumbing plans, what is the purpose of the abbreviation "DWV"?
A) Drainage, Waste, and Vent
B) Domestic Water Vent
C) Domestic Water Valve
D) Drainage, Water, and Ventilation
Explanation: "DWV" stands for Drainage, Waste, and Vent, which are critical components of a plumbing
system for waste removal.
4. What is the standard formula for calculating the water supply rate needed for a plumbing system?
A) Pressure x Diameter
B) Flow rate x Pipe length
C) Pipe size x Pressure
D) Fixture units x Pressure
Explanation: The water supply rate is generally calculated using fixture units and pressure, as this
impacts the overall water flow.
5. Which of the following terms refers to a type of joint that connects two pieces of pipe without using
heat or solvents?
A) Flanged joint
B) Push-fit joint
C) Soldered joint
D) Welded joint
,Explanation: A push-fit joint is a type of connection where no heat or solvents are required.
6. When installing backflow prevention devices, which of the following is the most common method
used to prevent contamination of potable water?
A) Air gap
B) Pressure relief valve
C) Check valve
D) Vacuum breaker
Explanation: The air gap is the most common method to prevent backflow by ensuring a physical
separation between potable water and potential contaminants.
7. Which plumbing material is commonly used for water supply pipes due to its corrosion resistance?
A) Cast iron
B) Galvanized steel
C) Copper
D) PVC
Explanation: Copper is widely used for water supply pipes because it resists corrosion and is durable
under pressure.
8. In plumbing, what does the term "head" refer to?
A) The pressure exerted by water in the system
B) The length of a pipe
C) The material of a pipe
D) The temperature of the water
Explanation: "Head" refers to the pressure exerted by water in a plumbing system due to gravity or
pump action.
9. What is the primary purpose of storm drainage systems in a plumbing design?
A) To direct water to a sewage treatment plant
B) To prevent flooding by directing excess rainwater away from structures
C) To store water for future use
D) To filter rainwater for potable use
Explanation: Storm drainage systems are designed to prevent flooding by efficiently directing excess
rainwater away from buildings and roads.
10. What is the most common type of material used for residential plumbing drain systems?
A) PVC
B) Copper
C) PEX
D) Galvanized steel
,Explanation: PVC is commonly used for drain systems due to its affordability, ease of installation, and
resistance to corrosion.
11. What administrative requirement must be completed before plumbing work can begin on a
construction site?
A) All plumbing fixtures must be ordered
B) A plumbing permit must be obtained
C) Plumbing plans must be drawn by an architect
D) All pipes must be pressure tested
Explanation: A plumbing permit must be obtained before work can begin on any plumbing installation,
as per local building codes.
12. What is the purpose of a plumbing test in new construction?
A) To check for leaks
B) To measure water flow rate
C) To ensure all pipes are correctly sized
D) To test the durability of fixtures
Explanation: A plumbing test is primarily used to check for leaks and ensure the system is sealed
correctly before use.
13. What is a common type of connection used to join copper pipes together in plumbing systems?
A) Compression fitting
B) Push-fit fitting
C) Soldered joint
D) Threaded connection
Explanation: Copper pipes are often joined using soldered joints, where a filler material is melted to seal
the connection.
14. In plumbing, what is the term for the system used to remove wastewater from a building?
A) Venting system
B) Storm drainage system
C) Waste and vent system
D) Drainage system
Explanation: The drainage system is responsible for removing wastewater from a building to the sewer
or septic system.
15. Which of the following plumbing symbols represents a toilet on blueprints?
A) A triangle with a "T"
B) A square with a "W"
C) A circle with two lines through it
D) A square with a "T" inside
, Explanation: A toilet is often represented by a square with a "T" inside it in plumbing blueprints.
16. What is the role of a pressure-reducing valve in a plumbing system?
A) To increase water pressure
B) To prevent backflow
C) To reduce water pressure to safe levels
D) To filter the water supply
Explanation: A pressure-reducing valve helps maintain safe water pressure levels, preventing damage to
the plumbing system.
17. Which of the following materials is most commonly used for drain, waste, and vent (DWV)
systems?
A) Cast iron
B) PEX
C) Copper
D) PVC
Explanation: PVC is most commonly used for DWV systems due to its low cost and ease of installation.
18. What does the term "backflow" refer to in plumbing systems?
A) The normal flow of water through pipes
B) The reverse flow of water into the potable water supply
C) The movement of waste through drain pipes
D) The filtration of water in a system
Explanation: Backflow occurs when water flows in the opposite direction, potentially contaminating the
clean water supply.
19. What is the primary function of a sump pump in a plumbing system?
A) To regulate water pressure
B) To remove excess water from a basement or crawlspace
C) To purify the water supply
D) To increase water flow to fixtures
Explanation: A sump pump is used to remove excess water, often from basements or crawl spaces,
preventing flooding.
20. What material is commonly used for the installation of exterior water lines due to its resistance to
freezing?
A) Cast iron
B) PVC
C) Copper
D) PEX
