UTAH PLUMBING CODE EXAM – QUESTIONS AND ANSWERS | VERIFIED AND WELL
DETAILED ANSWERS | PLUS RATIONALES | GUARANTEED PASS | LATEST EXAM UPDATE
CORE DOMAINS
- General Regulations and Administration- - Fixtures, Faucets, and Fixture Fittings- - Water
Heaters and Pressure Vessels- - Water Supply and Distribution Systems- - Sanitary Drainage
and Venting- - Indirect and Special Waste Systems- - Storm Drainage and Rainwater
Harvesting- - Medical Gas and Vacuum Systems- - Utah State Specific Amendments- -
Professional Standards and Safety Compliance-
INTRODUCTION
The Utah Plumbing Code Exam assessment is meticulously designed to evaluate a
candidate’s proficiency in the technical, legal, and safety standards governing the plumbing
profession within the state. This comprehensive examination assesses essential skills ranging
from system design and installation to maintenance and repair, grounded in the
International Plumbing Code and specific Utah amendments. Utilizing a blend of multiple-
choice and scenario-based inquiries, the exam challenges candidates to apply theoretical
knowledge to real-world applications, ensuring sound decision-making and public health
protection. This document serves as a rigorous preparatory tool to ensure candidates are
fully equipped for professional licensure and ethical practice.
SECTION ONE: QUESTIONS 1–100
1. Which of the following is the minimum clearance required in front of a water closet
to any wall, fixture, or door?
A. 15 inches B. 18 inches C. 21 inches D. 24 inches
C. 21 inches
Explanation: Per the plumbing code, a minimum of 21 inches of clear space must be
provided in front of a water closet, urinal, lavatory, or bidet to any wall, fixture, or door to
ensure accessibility and ease of use.
2. What is the minimum size of a building sewer permitted under the Utah Plumbing
Code?
A. 2 inches B. 3 inches C. 4 inches D. 6 inches
B. 3 inches
Explanation: The code specifies that the minimum size for a building sewer is 3 inches to
ensure adequate flow and prevent blockages for standard residential or commercial
structures.
, 3. Horizontal drainage piping shall be installed in practical alignment and at a uniform
slope. What is the minimum slope for a 2-inch diameter pipe?
A. 1/8 inch per foot B. 1/4 inch per foot C. 1/2 inch per foot D. 1 inch per foot
B. 1/4 inch per foot
Explanation: For pipes 2.5 inches or less in diameter, the minimum required slope is 1/4
inch per foot to maintain the scouring velocity necessary for solid waste transport.
4. A water heater temperature and pressure relief (T&P) valve discharge pipe shall
terminate not more than how many inches above the floor?
A. 2 inches B. 6 inches C. 12 inches D. 18 inches
B. 6 inches
Explanation: To prevent scalding and ensure safety, the discharge pipe from a T&P valve
must terminate atmospherically not more than 6 inches and not less than twice the
discharge pipe diameter above the floor or waste receptor.
5. In Utah, what is the maximum temperature setting allowed for public hand-washing
lavatories?
A. 105 degrees Fahrenheit B. 110 degrees Fahrenheit C. 120 degrees Fahrenheit D. 130
degrees Fahrenheit
B. 110 degrees Fahrenheit
Explanation: Public hand-washing facilities must be equipped with a tempering valve to
limit the water temperature to a maximum of 110 degrees Fahrenheit to prevent accidental
burns.
6. What is the required lead content limit for "lead-free" pipe and fittings intended to
convey water for human consumption?
A. 0.2 percent B. 0.25 percent C. 0.5 percent D. 8.0 percent
B. 0.25 percent
Explanation: Under the Safe Drinking Water Act and current plumbing codes, "lead-free"
refers to a weighted average lead content of not more than 0.25 percent for wetted surfaces
of pipes and fittings.
7. Which device is required to prevent backflow where a potable water supply connects
to a non-potable source?
A. Gate valve B. Check valve C. Backflow preventer D. Globe valve
, C. Backflow preventer
Explanation: A backflow preventer (such as an RPZ or double check valve assembly) is
required to protect the potable water supply from contamination or pollution due to back-
siphonage or back-pressure.
8. A vent stack shall be required for every building that has how many branch intervals?
A. Three or more B. Five or more C. Seven or more D. Ten or more
D. Ten or more
Explanation: A vent stack is mandatory for drainage stacks having ten or more branch
intervals to provide adequate air circulation and protect trap seals.
9. What is the maximum distance between a plumbing fixture trap and its vent for a
1.5-inch pipe?
A. 5 feet B. 6 feet C. 8 feet D. 10 feet
B. 6 feet
Explanation: For a 1.5-inch drain pipe, the maximum developed length between the trap
weir and the vent connection is 6 feet to ensure the trap seal is not compromised by
siphoning.
10. Which type of piping material is NOT approved for underground water services?
A. Type K copper B. Ductile iron C. PVC (Schedule 40) D. CPVC
C. PVC (Schedule 40)
Explanation: While PVC is used for drainage, standard Schedule 40 PVC is generally not
approved for pressurized underground water service lines within a building's footprint;
Schedule 80 or specific pressure-rated materials are required.
11. What is the minimum size of a water service pipe for a single-family dwelling?
A. 1/2 inch B. 3/4 inch C. 1 inch D. 1.25 inches
B. 3/4 inch
Explanation: The code requires a minimum of a 3/4-inch water service pipe to ensure
adequate volume and pressure for a standard residential dwelling.
12. Cleanouts on 6-inch and smaller pipes shall be provided at distances not exceeding:
A. 50 feet B. 75 feet C. 100 feet D. 150 feet
C. 100 feet
, Explanation: Horizontal drainage pipes must have cleanouts installed at intervals of not
more than 100 feet to allow for mechanical clearing of blockages.
13. Every trap shall have a liquid seal of not less than how many inches?
A. 1 inch B. 2 inches C. 3 inches D. 4 inches
B. 2 inches
Explanation: A minimum trap seal of 2 inches is required to prevent sewer gases from
entering the building while allowing for evaporation and pressure fluctuations.
14. What is the maximum horizontal spacing for supporting CPVC piping?
A. 3 feet B. 4 feet C. 6 feet D. 10 feet
B. 4 feet
Explanation: CPVC piping requires horizontal support at intervals not exceeding 4 feet to
prevent sagging and stress on joints.
15. When testing a DWV system with air, what is the required pressure and duration?
A. 5 psi for 10 minutes B. 5 psi for 15 minutes C. 10 psi for 15 minutes D. 10 psi for 30
minutes
B. 5 psi for 15 minutes
Explanation: An air test for a DWV system requires maintaining 5 psi for at least 15
minutes without any drop in pressure to verify system integrity.
16. A dishwasher drain must be connected to the sanitary drainage system through
which of the following?
A. Directly to the stack B. An air gap or air break C. A gate valve D. A 1-inch P-trap
B. An air gap or air break
Explanation: To prevent backflow from the sink or drainage system into the dishwasher,
an air gap or a high loop (depending on local amendment/manufacturer) is required; Utah
typically reinforces air gap use.
17. What is the minimum size for a floor drain?
A. 1.5 inches B. 2 inches C. 3 inches D. 4 inches
B. 2 inches
Explanation: Floor drains must have a minimum outlet size of 2 inches to handle
potential high volumes of water and prevent clogging.
DETAILED ANSWERS | PLUS RATIONALES | GUARANTEED PASS | LATEST EXAM UPDATE
CORE DOMAINS
- General Regulations and Administration- - Fixtures, Faucets, and Fixture Fittings- - Water
Heaters and Pressure Vessels- - Water Supply and Distribution Systems- - Sanitary Drainage
and Venting- - Indirect and Special Waste Systems- - Storm Drainage and Rainwater
Harvesting- - Medical Gas and Vacuum Systems- - Utah State Specific Amendments- -
Professional Standards and Safety Compliance-
INTRODUCTION
The Utah Plumbing Code Exam assessment is meticulously designed to evaluate a
candidate’s proficiency in the technical, legal, and safety standards governing the plumbing
profession within the state. This comprehensive examination assesses essential skills ranging
from system design and installation to maintenance and repair, grounded in the
International Plumbing Code and specific Utah amendments. Utilizing a blend of multiple-
choice and scenario-based inquiries, the exam challenges candidates to apply theoretical
knowledge to real-world applications, ensuring sound decision-making and public health
protection. This document serves as a rigorous preparatory tool to ensure candidates are
fully equipped for professional licensure and ethical practice.
SECTION ONE: QUESTIONS 1–100
1. Which of the following is the minimum clearance required in front of a water closet
to any wall, fixture, or door?
A. 15 inches B. 18 inches C. 21 inches D. 24 inches
C. 21 inches
Explanation: Per the plumbing code, a minimum of 21 inches of clear space must be
provided in front of a water closet, urinal, lavatory, or bidet to any wall, fixture, or door to
ensure accessibility and ease of use.
2. What is the minimum size of a building sewer permitted under the Utah Plumbing
Code?
A. 2 inches B. 3 inches C. 4 inches D. 6 inches
B. 3 inches
Explanation: The code specifies that the minimum size for a building sewer is 3 inches to
ensure adequate flow and prevent blockages for standard residential or commercial
structures.
, 3. Horizontal drainage piping shall be installed in practical alignment and at a uniform
slope. What is the minimum slope for a 2-inch diameter pipe?
A. 1/8 inch per foot B. 1/4 inch per foot C. 1/2 inch per foot D. 1 inch per foot
B. 1/4 inch per foot
Explanation: For pipes 2.5 inches or less in diameter, the minimum required slope is 1/4
inch per foot to maintain the scouring velocity necessary for solid waste transport.
4. A water heater temperature and pressure relief (T&P) valve discharge pipe shall
terminate not more than how many inches above the floor?
A. 2 inches B. 6 inches C. 12 inches D. 18 inches
B. 6 inches
Explanation: To prevent scalding and ensure safety, the discharge pipe from a T&P valve
must terminate atmospherically not more than 6 inches and not less than twice the
discharge pipe diameter above the floor or waste receptor.
5. In Utah, what is the maximum temperature setting allowed for public hand-washing
lavatories?
A. 105 degrees Fahrenheit B. 110 degrees Fahrenheit C. 120 degrees Fahrenheit D. 130
degrees Fahrenheit
B. 110 degrees Fahrenheit
Explanation: Public hand-washing facilities must be equipped with a tempering valve to
limit the water temperature to a maximum of 110 degrees Fahrenheit to prevent accidental
burns.
6. What is the required lead content limit for "lead-free" pipe and fittings intended to
convey water for human consumption?
A. 0.2 percent B. 0.25 percent C. 0.5 percent D. 8.0 percent
B. 0.25 percent
Explanation: Under the Safe Drinking Water Act and current plumbing codes, "lead-free"
refers to a weighted average lead content of not more than 0.25 percent for wetted surfaces
of pipes and fittings.
7. Which device is required to prevent backflow where a potable water supply connects
to a non-potable source?
A. Gate valve B. Check valve C. Backflow preventer D. Globe valve
, C. Backflow preventer
Explanation: A backflow preventer (such as an RPZ or double check valve assembly) is
required to protect the potable water supply from contamination or pollution due to back-
siphonage or back-pressure.
8. A vent stack shall be required for every building that has how many branch intervals?
A. Three or more B. Five or more C. Seven or more D. Ten or more
D. Ten or more
Explanation: A vent stack is mandatory for drainage stacks having ten or more branch
intervals to provide adequate air circulation and protect trap seals.
9. What is the maximum distance between a plumbing fixture trap and its vent for a
1.5-inch pipe?
A. 5 feet B. 6 feet C. 8 feet D. 10 feet
B. 6 feet
Explanation: For a 1.5-inch drain pipe, the maximum developed length between the trap
weir and the vent connection is 6 feet to ensure the trap seal is not compromised by
siphoning.
10. Which type of piping material is NOT approved for underground water services?
A. Type K copper B. Ductile iron C. PVC (Schedule 40) D. CPVC
C. PVC (Schedule 40)
Explanation: While PVC is used for drainage, standard Schedule 40 PVC is generally not
approved for pressurized underground water service lines within a building's footprint;
Schedule 80 or specific pressure-rated materials are required.
11. What is the minimum size of a water service pipe for a single-family dwelling?
A. 1/2 inch B. 3/4 inch C. 1 inch D. 1.25 inches
B. 3/4 inch
Explanation: The code requires a minimum of a 3/4-inch water service pipe to ensure
adequate volume and pressure for a standard residential dwelling.
12. Cleanouts on 6-inch and smaller pipes shall be provided at distances not exceeding:
A. 50 feet B. 75 feet C. 100 feet D. 150 feet
C. 100 feet
, Explanation: Horizontal drainage pipes must have cleanouts installed at intervals of not
more than 100 feet to allow for mechanical clearing of blockages.
13. Every trap shall have a liquid seal of not less than how many inches?
A. 1 inch B. 2 inches C. 3 inches D. 4 inches
B. 2 inches
Explanation: A minimum trap seal of 2 inches is required to prevent sewer gases from
entering the building while allowing for evaporation and pressure fluctuations.
14. What is the maximum horizontal spacing for supporting CPVC piping?
A. 3 feet B. 4 feet C. 6 feet D. 10 feet
B. 4 feet
Explanation: CPVC piping requires horizontal support at intervals not exceeding 4 feet to
prevent sagging and stress on joints.
15. When testing a DWV system with air, what is the required pressure and duration?
A. 5 psi for 10 minutes B. 5 psi for 15 minutes C. 10 psi for 15 minutes D. 10 psi for 30
minutes
B. 5 psi for 15 minutes
Explanation: An air test for a DWV system requires maintaining 5 psi for at least 15
minutes without any drop in pressure to verify system integrity.
16. A dishwasher drain must be connected to the sanitary drainage system through
which of the following?
A. Directly to the stack B. An air gap or air break C. A gate valve D. A 1-inch P-trap
B. An air gap or air break
Explanation: To prevent backflow from the sink or drainage system into the dishwasher,
an air gap or a high loop (depending on local amendment/manufacturer) is required; Utah
typically reinforces air gap use.
17. What is the minimum size for a floor drain?
A. 1.5 inches B. 2 inches C. 3 inches D. 4 inches
B. 2 inches
Explanation: Floor drains must have a minimum outlet size of 2 inches to handle
potential high volumes of water and prevent clogging.
