VERIFIED AND WELL DETAILED ANSWERS | PLUS RATIONALES | GUARANTEED PASS |
LATEST EXAM UPDATE
*Core Domains*
*Plumbing Fundamentals and Theory*
*Water Distribution Systems*
*Sanitary Drainage and Venting*
*Fuel Gas Piping and Appliances*
*Water Heaters and Storage Tanks*
*Fixtures, Faucets, and Fittings*
*Utah State Amendments and Regulations*
*Cross-Connection Control*
*Introduction*
*The purpose of this assessment is to evaluate the competency and technical
proficiency*
*of candidates seeking licensure as a Residential Journeyman Plumber in Utah. This*
*exam covers critical knowledge areas including code compliance, system design,
and*
*safety standards. The structure utilizes multiple-choice questions and complex*
*scenario-based problems to mirror real-world field conditions. Candidates must*
*demonstrate an ability to apply regulatory requirements to residential installations,*
*ensure public health through proper backflow prevention, and make sound
technical*
*decisions. This comprehensive guide serves as a rigorous tool for final preparation*
*and professional verification.*
SECTION ONE: QUESTIONS 1–100
, 1. What is the minimum required size for a residential building sewer in most
jurisdictions?
A. 2 inches B. 3 inches C. 4 inches D. 6 inches
Correct answer C. 4 inches
Explanation: Standard residential codes generally require a minimum of 4 inches for
building sewers to handle the aggregate load of a single-family dwelling and prevent
frequent blockages.
2. Which of the following is required when a plumbing fixture is installed in a basement
where the overflow rim is below the level of the manhole cover of the next upstream
manhole in the public sewer?
A. A vacuum breaker B. A backwater valve C. An air gap D. A relief valve
Correct answer B. A backwater valve
Explanation: Backwater valves are mandatory for fixtures located below the level of the
upstream sewer manhole to prevent sewage from backing up into the lower levels of a
home.
3. In a water distribution system, what is the maximum permitted water pressure at a
fixture?
A. 60 psi B. 80 psi C. 100 psi D. 120 psi
Correct answer B. 80 psi
Explanation: To protect fixtures and piping from excessive wear and potential failure,
pressure-reducing valves must be installed if the supply pressure exceeds 80 psi.
4. A "cleanout" for a 4-inch pipe must have a minimum clearance of how many inches
in front of it?
A. 12 inches B. 18 inches C. 24 inches D. 36 inches
Correct answer B. 18 inches
Explanation: For pipes 4 inches or larger, code requires at least 18 inches of clearance to
allow for proper rodding and maintenance access.
5. What is the minimum depth of a trap seal for a standard plumbing fixture?
A. 1 inch B. 2 inches C. 4 inches D. 6 inches
Correct answer B. 2 inches
, Explanation: Most codes specify a trap seal depth between 2 inches and 4 inches to
ensure sewer gases are blocked effectively while still allowing self-scouring action.
6. When testing a DWV system with air, what pressure must be maintained for at least
15 minutes?
A. 3 psi B. 5 psi C. 10 psi D. 15 psi
Correct answer B. 5 psi
Explanation: An air test on a drainage and vent system requires a minimum pressure of 5
pounds per square inch (psi) to verify the integrity of the joints and material.
7. Which material is generally prohibited for use as a water distribution pipe inside a
residential building?
A. Copper (Type L) B. CPVC C. PEX D. Black steel
Correct answer D. Black steel
Explanation: Black steel pipe is used for gas or steam but is not suitable for potable
water distribution because it will corrode and contaminate the water supply.
8. What is the maximum horizontal distance allowed for a 2-inch trap arm?
A. 3 feet B. 5 feet C. 6 feet D. 8 feet
Correct answer D. 8 feet
Explanation: Based on standard slope requirements (1/4 inch per foot), a 2-inch trap arm
is limited to 8 feet to ensure the vent remains effective and siphoning does not occur.
9. A water heater temperature and pressure (T&P) relief valve discharge pipe must
terminate no more than how many inches above the floor?
A. 2 inches B. 6 inches C. 12 inches D. 18 inches
Correct answer B. 6 inches
Explanation: The discharge pipe must terminate between the indirect waste receptor
and the floor, specifically not more than 6 inches above the floor to prevent splashing and
injury.
10. Which type of venting relies on the drainage pipe itself to provide the air supply?
A. Individual vent B. Common vent C. Wet vent D. Circuit vent
Correct answer C. Wet vent
, Explanation: A wet vent is a pipe that serves as both a drain for one or more fixtures and
a vent for others, utilizing the top half of the pipe for airflow.
11. What is the minimum required slope for a 2-1/2 inch or smaller horizontal drainage
pipe?
A. 1/8 inch per foot B. 1/4 inch per foot C. 1/2 inch per foot D. 1 inch per foot
Correct answer B. 1/4 inch per foot
Explanation: To maintain adequate scouring velocity for solids in pipes 2-1/2 inches or
smaller, a minimum slope of 1/4 inch per foot is required.
12. A plumbing apprentice is installing a garbage disposal. What type of connection is
required for the dishwasher drain to the disposal?
A. A direct coupling B. An air gap or high loop C. A check valve D. A secondary trap
Correct answer B. An air gap or high loop
Explanation: To prevent backflow from the sink or disposal into the dishwasher, an air
gap (standard in many codes) or a high loop is required.
13. What is the maximum distance between a water heater and its required shut-off
valve?
A. 3 feet B. Within the same room C. 10 feet D. There is no distance limit
Correct answer B. Within the same room
Explanation: The cold water supply shut-off valve must be in the same room as the water
heater and accessible to allow for quick isolation during emergencies.
14. Which of these is an example of a "non-potable" water source?
A. City main supply B. Well water tested for safety C. Rainwater harvesting tank D. Filtered
kitchen faucet water
Correct answer C. Rainwater harvesting tank
Explanation: Rainwater is considered non-potable and must be kept separate from the
drinking water system unless treated to meet specific health standards.
15. What is the minimum size of a water service pipe from the street to a typical single-
family residence?
A. 1/2 inch B. 3/4 inch C. 1 inch D. 1-1/4 inch
Correct answer B. 3/4 inch