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NV Journeyman Plumber practice questions

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Question 1Plumbing Terminology, Definitions, and Code Administration

Under the Nevada Plumbing Code adopted by the state, which document is the primary model code that jurisdictions enforce for plumbing installations?

  1. The National Electrical Code
  2. The Uniform Plumbing Code Correct answer.
  3. The International Energy Conservation Code
  4. The International Fire Code

Explanation

Nevada adopts the Uniform Plumbing Code, published by the International Association of Plumbing and Mechanical Officials, as the basis for plumbing regulation in the state. The other documents govern fire, electrical, and energy matters and do not set plumbing installation rules.

Question 2Plumbing Terminology, Definitions, and Code Administration

A plumbing term describing the vertical distance a trap seal can be pushed or pulled before it breaks is called the:

  1. Fixture drain
  2. Vent stack
  3. Trap arm
  4. Seal depth Correct answer.

Explanation

Seal depth is the vertical distance between the crown weir of the trap and the lowest point of the trap dip, representing the water column that resists pressure changes. Trap arms, fixture drains, and vent stacks are piping components rather than a measurement of the water seal.

Question 3Plumbing Terminology, Definitions, and Code Administration

In plumbing terminology, a fixture that discharges into the drainage system with a direct connection and no backflow protection is referred to as:

  1. Backflow prevented
  2. Directly connected Correct answer.
  3. Indirectly wasted
  4. Air-gapped

Explanation

A directly connected fixture drains through a solid pipe connection to the drainage system without an air gap or air break. Indirectly wasted fixtures discharge through an air gap into a receptor, and air-gapped describes that protected arrangement.

Question 4Plumbing Terminology, Definitions, and Code Administration

The authority having jurisdiction for plumbing inspections in a Nevada county or city is best defined as:

  1. The building owner of record
  2. The registered design professional who sealed the plans
  3. The plumbing contractor performing the work
  4. The official or agency responsible for enforcing the code Correct answer.

Explanation

The authority having jurisdiction is the organization, office, or individual responsible for approving equipment, materials, installations, and enforcement of code requirements. Contractors, designers, and owners have roles in a project but do not hold enforcement authority.

Question 5Plumbing Terminology, Definitions, and Code Administration

Which term describes the lowest horizontal piping of a drainage system that receives soil and waste from building drains and conveys it to the public sewer?

  1. Building drain
  2. Building sewer Correct answer.
  3. House trap
  4. Soil stack

Explanation

The building sewer is the lowest piping section that carries sewage from the building drain to the sewer or private disposal system. The building drain is the portion inside the building that conveys waste to the building sewer.

Question 6Plumbing Terminology, Definitions, and Code Administration

A plumbing contractor in Nevada must obtain a permit before beginning work. Which statement best describes the general code requirement for permits?

  1. Permits are optional if the contractor is licensed
  2. Permits are required only for commercial buildings
  3. Permits are required before installation of plumbing systems except for minor repairs exempted by the code Correct answer.
  4. Permits are required only when the work exceeds one thousand dollars

Explanation

Plumbing codes require a permit before installing or altering a plumbing system, with narrow exemptions for minor repair work such as clearing stoppages or replacing fixture trim. Licensing does not substitute for a permit, and exemptions are not based on building type or dollar value.

Question 7Plumbing Terminology, Definitions, and Code Administration

During an inspection, a code official finds an installed water heater lacking a required temperature and pressure relief valve. What is the most appropriate administrative action?

  1. Approve the installation with a written note for the next inspection
  2. Take no action because relief valves are optional accessories
  3. Refer the matter to the contractor's licensing board for discipline
  4. Issue a correction notice requiring compliance before approval Correct answer.

Explanation

When work does not comply, the code official issues a notice of correction identifying the deficiency and requiring it to be fixed before the installation can be approved. Approval with a note, licensing discipline, or inaction would not enforce the code requirement for a relief valve.

Question 8Plumbing Terminology, Definitions, and Code Administration

A 'developed length' of a plumbing system, as used in code sizing tables, refers to:

  1. The horizontal distance only between the building and the sewer
  2. The vertical rise of the vent stack above the roof
  3. The total length of pipe plus fittings measured along the centerline of the flow path Correct answer.
  4. The linear distance of the water service trench

Explanation

Developed length is the measured length along the centerline of pipe and fittings, including the equivalent length added by fittings. Sizing tables for drainage and water piping rely on this total because fittings add friction loss.

Question 9Plumbing Terminology, Definitions, and Code Administration

A code defines 'flood level rim' as:

  1. The elevation of the building sewer invert
  2. The top edge of a fixture receptor from which water overflows Correct answer.
  3. The highest point of a vent terminal
  4. The rim of a floor drain strainer

Explanation

The flood level rim is the edge of the receptacle from which water overflows, and it establishes the minimum air gap or backflow protection height for fixtures. Vent terminals, sewer inverts, and strainer rims are unrelated elevations.

Question 10Plumbing Terminology, Definitions, and Code Administration

A plumbing contractor wants to substitute a listed fitting for one specified on approved plans. Under typical code administration provisions, what must occur first?

  1. The building owner must sign a waiver accepting the substitution
  2. The substitution must be approved by the authority having jurisdiction before installation Correct answer.
  3. The supplier must certify the fitting is equivalent after installation
  4. The contractor may install any listed equivalent without notice

Explanation

Alternate materials and methods require approval by the authority having jurisdiction before use, typically through a written request demonstrating equivalence. Unilateral substitution, after-the-fact certification, or owner waivers do not satisfy code approval requirements.

Question 11Plumbing Terminology, Definitions, and Code Administration

The term 'air break' in plumbing code terminology is best described as:

  1. A valve that opens automatically on backflow
  2. A physical separation between a fixture outlet and the flood level rim of a receptor
  3. A pipe arrangement in which the drain discharges below the flood level rim of a receptor Correct answer.
  4. A vent connection joining two stacks

Explanation

An air break is a drain discharge that enters a receptor below its flood level rim, relying on the receptor's overflow to prevent backflow. It differs from an air gap, which is a physical separation above the flood level rim.

Question 12Plumbing Terminology, Definitions, and Code Administration

In drainage terminology, the 'crown weir' of a trap is located at:

  1. The invert of the trap outlet where it begins to slope
  2. The connection point of the trap arm to the vent
  3. The top of the trap dip where the outlet leg begins Correct answer.
  4. The lowest inside point of the trap dip

Explanation

The crown weir is the top of the trap dip, the point where the outlet leg begins, and it marks the level to which the trap seal rises. The lowest dip point is the trap dip, and the trap arm connection to the vent is a separate location.

Question 13Plumbing Terminology, Definitions, and Code Administration

A code official cites a 'combination waste and vent system.' Which description matches that term?

  1. A system in which every fixture has an individual vent through the roof
  2. A system using a single stack for both soil and vent with no fixture vents
  3. A system where the drain also serves as the vent for fixtures on the same line Correct answer.
  4. A system where vents are omitted entirely

Explanation

A combination waste and vent system uses a drain pipe sized and installed so it also provides venting for connected fixtures, typically for fixtures in a battery. Individual venting, single-stack arrangements, and unvented systems are distinct configurations.

Question 14Plumbing Terminology, Definitions, and Code Administration

A plan reviewer notes that a horizontal drain must be installed with a uniform slope. Which code term describes the fall per unit length used to size and install the pipe?

  1. Head
  2. Fall velocity
  3. Grade Correct answer.
  4. Static pressure

Explanation

Grade is the slope of a pipe expressed as fall per unit of length, such as one-quarter inch per foot, and it is a required installation parameter for horizontal drainage piping. Head and static pressure describe fluid energy, and fall velocity is not a code slope term.

Question 15Plumbing Terminology, Definitions, and Code Administration

A plumbing inspector is asked to interpret whether a proposed fixture qualifies as a 'fixture unit.' Which statement best captures the concept?

  1. One gallon of water discharged per minute by any fixture
  2. The number of fixtures connected to one vent
  3. The physical size of the fixture trap in inches
  4. A measure of the probable rate of drainage discharge from a fixture relative to a standard Correct answer.

Explanation

A fixture unit is a relative measure of the probable drainage load a fixture imposes, with one fixture unit defined by a standard discharge rate. It is not a simple gallon-per-minute rating, a trap dimension, or a count of fixtures per vent.

Question 16Plumbing Terminology, Definitions, and Code Administration

A contractor proposes to install a plumbing system using an alternative method not described in the code. Which administrative path best satisfies code administration requirements?

  1. Submit a written request to the authority having jurisdiction showing the method is equivalent in safety and performance Correct answer.
  2. Have the manufacturer publish a brochure describing the method
  3. Obtain the owner's written consent to the method
  4. Install it and request approval at the final inspection

Explanation

Alternative methods require prior written approval from the authority having jurisdiction, supported by evidence of equivalent safety and performance. Installing first, relying on marketing materials, or obtaining owner consent does not meet the approval requirement.

Question 17General Regulations, Permits, and Inspections

Under the Nevada plumbing regulations, who is authorized to obtain a plumbing permit for work on a single-family residence the owner occupies?

  1. Any person holding a journeyman plumber certificate
  2. The local building official acting as agent for the owner
  3. Only a licensed plumbing contractor
  4. The property owner who occupies the residence, or a licensed plumbing contractor Correct answer.

Explanation

Nevada law allows the owner of a single-family residence that the owner occupies to take out permits for work on that dwelling, and licensed plumbing contractors may also obtain permits. A journeyman certificate alone does not authorize permit issuance because the journeyman must work under a licensed contractor. The building official issues and inspects permits but does not obtain them on the owner's behalf.

Question 18General Regulations, Permits, and Inspections

A plumbing contractor begins replacing a water service line and asks what must occur before the trench is backfilled. What does the typical Nevada inspection sequence require?

  1. The inspection may be waived if the contractor submits a signed affidavit
  2. The underground piping must be inspected and approved before it is covered Correct answer.
  3. The trench may be backfilled once the contractor photographs the installation
  4. No inspection is needed if the pipe is rated for the pressure

Explanation

Underground piping such as water services, building drains, and building sewers must be inspected and approved before being covered or concealed. This allows the inspector to verify materials, slope, bedding, and joints while they are still visible. Photographs or affidavits do not substitute for the required inspection unless the authority having jurisdiction specifically allows an alternative.

Question 19General Regulations, Permits, and Inspections

A journeyman plumber is performing work under a licensed plumbing contractor. Which statement best describes the journeyman's relationship to the permit and inspection process?

  1. The journeyman may independently obtain the permit and request inspections in the journeyman's own name
  2. The journeyman must apply for a separate journeyman permit before starting each job
  3. The journeyman works under the contractor's license, and the permit is issued to the contractor who is responsible for the work Correct answer.
  4. The journeyman is exempt from inspection requirements because the work is supervised

Explanation

Permits are issued to the licensed contractor responsible for the project, and journeymen perform the work under that contractor's license and supervision. The journeyman does not obtain a separate permit in his or her own name for the contractor's project. Inspection requirements apply to the work regardless of who physically performs it.

Question 20General Regulations, Permits, and Inspections

A homeowner in Nevada wants to do plumbing work on a duplex the owner rents to tenants. Which statement reflects the usual permit rule?

  1. The owner may pull the permit only if the work costs less than a set dollar amount
  2. The owner may pull the permit if a journeyman agrees to supervise informally
  3. The owner-occupant exemption generally does not apply, so a licensed plumbing contractor must obtain the permit Correct answer.
  4. The owner may pull the permit because the owner holds title to the property

Explanation

The owner-builder permit allowance in Nevada is generally limited to a single-family residence that the owner actually occupies. A rental duplex does not qualify, so the work must be permitted through a licensed plumbing contractor. Informal supervision by a journeyman does not create an owner permit entitlement.

Question 21General Regulations, Permits, and Inspections

During a rough-in inspection, an inspector finds that a building drain has been installed with insufficient slope. What is the most likely consequence under the inspection process?

  1. The inspector issues a correction notice, and the work must be corrected and reinspected before approval Correct answer.
  2. The inspector must accept the drain if the fixture clearances are otherwise adequate
  3. The contractor may proceed if the slope is corrected before the certificate of occupancy is requested
  4. The inspector approves the work conditionally and notes it for the final inspection only

Explanation

When work fails inspection, the authority having jurisdiction issues a correction notice identifying the deficiency, and the contractor must correct it and request a reinspection. Approval is not granted until the corrected work passes. Concealing or deferring the defect to a later stage is not permitted.

Question 22General Regulations, Permits, and Inspections

A contractor needs to know the required inspection stages for a new commercial plumbing system. Which sequence best reflects typical requirements?

  1. Rough-in and final inspections, with underground piping inspected before concealment Correct answer.
  2. Inspection only when the authority having jurisdiction receives a complaint
  3. A single inspection at the midpoint of construction
  4. Final inspection only, after all fixtures are set

Explanation

Plumbing codes and local inspection programs generally require underground piping to be inspected before covering, a rough-in inspection before walls and ceilings are closed, and a final inspection after fixtures and trim are installed. Skipping intermediate inspections prevents verification of concealed work. Complaints do not trigger the standard inspection schedule.

Question 23General Regulations, Permits, and Inspections

A plumbing contractor wants to begin work before the permit has been issued because of a schedule conflict. What is the correct approach under Nevada permitting rules?

  1. Start the work and apply for the permit within 30 days
  2. Obtain the permit before beginning the work, unless the authority having jurisdiction grants an exception Correct answer.
  3. Start the work if the contractor has an active license and notifies the building department by phone
  4. Start only the underground portion, since it will be inspected later

Explanation

Plumbing work requiring a permit may not begin until the permit has been issued and, where required, the appropriate inspections are requested. Starting work early exposes the contractor to stop-work orders, penalties, and required removal of concealed work. A phone notification or license status does not substitute for an issued permit.

Question 24General Regulations, Permits, and Inspections

An inspector arrives for a scheduled rough-in inspection and finds no one on site and the work area locked. What is the typical result?

  1. The inspector reschedules automatically at no cost to the contractor
  2. The inspection is recorded as not ready or inaccessible, and a reinspection fee may apply Correct answer.
  3. The inspector approves the work based on the previous inspection record
  4. The permit is automatically revoked and must be reapplied for

Explanation

If the work is not ready or the site is inaccessible when the inspector arrives, the inspection cannot be performed and is typically recorded as a failed or not-ready inspection. Many jurisdictions charge a reinspection fee for the return trip. The permit is not automatically revoked, and the contractor is responsible for requesting a new inspection.

Question 25General Regulations, Permits, and Inspections

A contractor completes plumbing alterations on an existing building and receives a final approval. What document typically confirms that the permitted work is approved for use?

  1. A material certification from the pipe manufacturer
  2. A certificate of occupancy or final inspection approval issued by the authority having jurisdiction Correct answer.
  3. A journeyman certificate card issued by the state
  4. A contractor's signed invoice to the building owner

Explanation

Final inspection approval, and where applicable a certificate of occupancy, documents that the permitted work has been inspected and approved. Invoices, license cards, and manufacturer certifications do not serve as official approval of the installation. The authority having jurisdiction issues the approval document.

Question 26General Regulations, Permits, and Inspections

A plumbing contractor discovers that the approved plans do not match conditions in the field and a drain must be relocated. What is the proper step before proceeding?

  1. Proceed with the change and note it on the as-built drawings at the end of the project
  2. Proceed if the relocated drain still meets code minimums
  3. Ask the general contractor to approve the change on the owner's behalf
  4. Obtain approval of the revised plans or a field revision from the authority having jurisdiction before installing the change Correct answer.

Explanation

When field conditions require a deviation from approved plans, the contractor must obtain approval of the revision from the authority having jurisdiction before installing it. This keeps the permit record accurate and ensures the change is inspected. Informal approval from the general contractor or code compliance alone does not amend the permit.

Question 27General Regulations, Permits, and Inspections

Which situation most clearly requires a plumbing permit in Nevada?

  1. Replacing a toilet fill valve with an identical valve
  2. Installing a new floor drain and connecting it to the building drain Correct answer.
  3. Replacing a faucet aerator on a kitchen sink
  4. Clearing a hair clog from a lavatory trap with a hand auger

Explanation

Installing a new floor drain and making a connection to the building drain is plumbing work that adds a fixture and alters the drainage system, so it requires a permit and inspection. Ordinary maintenance such as clearing a stoppage or replacing minor trim parts generally does not require a permit. The distinction turns on whether the work modifies the piping system.

Question 28General Regulations, Permits, and Inspections

A contractor is cited for performing plumbing work without a permit. Which outcome is most consistent with Nevada enforcement practice?

  1. The citation is void because only the property owner can be cited
  2. The contractor may simply pay the standard permit fee retroactively with no further action
  3. The work may be subject to a stop-work order, penalties, and required inspection or removal of concealed work Correct answer.
  4. The contractor may avoid penalties by obtaining a permit after the final inspection

Explanation

Unpermitted plumbing work exposes the contractor to stop-work orders, civil penalties, and the requirement to expose or remove concealed work so it can be inspected. Retroactive permit fees alone do not resolve the violation. Enforcement applies to the contractor performing the work, not only to the property owner.

Question 29General Regulations, Permits, and Inspections

Before a plumbing permit can be issued for a new building, which item is generally required as part of the submittal?

  1. A performance bond covering the entire construction cost
  2. A completed final inspection request form
  3. A copy of the contractor's license and plans or documentation sufficient to show the scope of work Correct answer.
  4. A notarized statement from each journeyman on the crew

Explanation

Permit applications typically require the licensed contractor's information and plans or scope documentation sufficient for the authority to review the proposed work. This allows plan review and proper inspection scheduling. Journeyman statements and final inspection forms are not part of the initial permit submittal.

Question 30General Regulations, Permits, and Inspections

A plumbing contractor is working on a project where the local jurisdiction has adopted a newer edition of the plumbing code than the edition the contractor normally uses. Which code edition governs the permitted work?

  1. The edition adopted by the authority having jurisdiction and in effect at the time the permit is issued Correct answer.
  2. The edition the contractor used on the most recent similar project
  3. Whichever edition is less expensive for the contractor to comply with
  4. The edition in effect when the contractor was licensed

Explanation

The code edition adopted by the authority having jurisdiction and in effect when the permit is issued governs the work, unless a specific transition or savings provision applies. Contractors must verify the locally adopted edition before design and installation. Prior practice or licensing date does not override the adopted code.

Question 31General Regulations, Permits, and Inspections

An inspector observes that a contractor has covered a newly installed building sewer with backfill before requesting inspection. The contractor argues the work was done correctly. How should the inspector's response be analyzed?

  1. The inspector may require the sewer to be uncovered for inspection before approving it Correct answer.
  2. The inspector should approve it because sewers are exempt from concealment rules
  3. The inspector should approve it if the pipe material is listed for underground use
  4. The inspector must approve it if the contractor provides a written warranty of correctness

Explanation

Building sewers and other underground piping must be inspected before being covered, so the authority having jurisdiction may require the contractor to uncover the work for inspection. A written warranty or listed material does not substitute for the required inspection. Approval cannot be based on the contractor's assurance alone.

Question 32General Regulations, Permits, and Inspections

A property owner occupies one unit of a duplex and rents the other unit. The owner wants to replumb the kitchen in the owner-occupied unit. Which analysis of the permit requirement is most accurate?

  1. The owner may perform the work without a permit because it is inside the owner's own unit
  2. The owner may pull the permit only if the rented unit is vacant during construction
  3. Whether the owner-occupant allowance applies depends on how the jurisdiction treats the duplex, so the owner should confirm with the authority having jurisdiction before proceeding Correct answer.
  4. The owner qualifies automatically because the owner lives in the building

Explanation

The owner-occupant permit allowance is generally tied to a single-family residence occupied by the owner, and a duplex may or may not fall within that allowance depending on local interpretation. Because the outcome is not automatic, the owner should confirm with the authority having jurisdiction before doing the work. A licensed plumbing contractor can always obtain the permit if the owner allowance does not apply.

Question 33Fixtures, Fixture Fittings, and Water Heaters

A water closet is installed in a public restroom. Which flush volume is the maximum allowed for a single-flush tank-type water closet under current federal standards?

  1. 1.28 gallons per flush
  2. 3.5 gallons per flush
  3. 0.8 gallons per flush
  4. 1.6 gallons per flush Correct answer.

Explanation

Federal standards cap tank-type water closets at 1.6 gallons per flush, a limit that has applied to new fixtures since the 1990s. Lower figures such as 1.28 gpf reflect high-efficiency products that exceed the minimum requirement but are not the legal maximum.

Question 34Fixtures, Fixture Fittings, and Water Heaters

A lavatory faucet in a residential bathroom is replaced. What is the maximum flow rate permitted for the new faucet?

  1. 2.5 gallons per minute
  2. 1.5 gallons per minute Correct answer.
  3. 2.2 gallons per minute
  4. 1.0 gallon per minute

Explanation

Residential lavatory faucets are limited to 1.5 gallons per minute at 60 psi under the federal fixture efficiency standard. Kitchen faucets are allowed 2.2 gpm, and older 2.5 gpm lavatory faucets predate the current rule.

Question 35Fixtures, Fixture Fittings, and Water Heaters

A showerhead in a single-family dwelling is being replaced. What maximum flow rate applies to the new showerhead?

  1. 2.0 gallons per minute
  2. 1.5 gallons per minute
  3. 3.0 gallons per minute
  4. 2.5 gallons per minute Correct answer.

Explanation

Showerheads are limited to 2.5 gallons per minute at 80 psi. This figure applies whether the head is fixed or handheld, and multiple heads on a single supply must be evaluated against the same limit.

Question 36Fixtures, Fixture Fittings, and Water Heaters

A water heater is installed in a garage. Which condition is required for the ignition source protection of a residential garage installation?

  1. The water heater must be elevated so the ignition source is at least 18 inches above the floor Correct answer.
  2. The water heater must be provided with a double-wall flue
  3. The water heater must be installed on a 4-inch concrete pad
  4. The water heater must be enclosed in a fire-rated cabinet

Explanation

In garages, the ignition source of a fuel-fired water heater must be elevated at least 18 inches above the floor to reduce the chance of igniting gasoline vapors, which are heavier than air. A concrete pad alone does not provide the required elevation.

Question 37Fixtures, Fixture Fittings, and Water Heaters

A temperature and pressure relief valve on a storage water heater must be located in which position relative to the tank?

  1. On the vent connector above the draft hood
  2. On the tank or on the hot water outlet within 6 inches of the tank Correct answer.
  3. On the cold water inlet line within 12 inches of the tank
  4. On the drain valve at the bottom of the tank

Explanation

The T&P relief valve must be installed directly on the tank or on the hot water outlet piping within 6 inches of the tank shell so it senses tank temperature and pressure. Mounting it on the cold inlet or drain valve would not protect the tank properly.

Question 38Fixtures, Fixture Fittings, and Water Heaters

A water heater's temperature and pressure relief valve discharge pipe is being installed. Which arrangement is acceptable?

  1. Discharging through an air gap to a receptor with the pipe terminating not more than 6 inches above the floor Correct answer.
  2. Trapping the discharge line to prevent sewer gas from escaping
  3. Connecting the discharge directly to the drainage system with a trap
  4. Running the discharge line with an upward slope to a floor drain

Explanation

The relief valve discharge must terminate through an air gap, typically not more than 6 inches above the floor or receptor, so a discharge is visible and cannot back up into the tank. It must not be trapped, connected directly to drainage, or sloped upward.

Question 39Fixtures, Fixture Fittings, and Water Heaters

A water heater is installed in a seismic zone. Which component is required to restrain the tank?

  1. A vacuum relief valve on the cold inlet
  2. A thermal expansion tank on the cold inlet
  3. Two straps, one in the upper third and one in the lower third of the tank Correct answer.
  4. A check valve on the hot outlet

Explanation

Seismic restraint for a storage water heater typically requires two straps or earthquake straps, one placed in the upper third and one in the lower third of the tank, anchored to the structure. These keep the tank from toppling during ground motion.

Question 40Fixtures, Fixture Fittings, and Water Heaters

A backflow prevention device is installed on the cold water supply to a water heater. What additional component is typically required to control thermal expansion?

  1. A second check valve
  2. A vacuum breaker
  3. A thermal expansion tank Correct answer.
  4. A pressure-reducing valve

Explanation

When a check valve or backflow preventer isolates the water heater from the public supply, heated water has nowhere to expand and pressure rises. A thermal expansion tank provides an air cushion to absorb that expansion and protect the system.

Question 41Fixtures, Fixture Fittings, and Water Heaters

A gas-fired water heater is installed in a small closet. Which condition is necessary for proper combustion air and venting?

  1. The closet must be provided with combustion air openings sized to the appliance input and the space volume Correct answer.
  2. The closet must have a solid door with no openings
  3. The closet must be pressurized by a supply duct
  4. The water heater must be installed with a direct-vent kit even if not listed for it

Explanation

A confined space requires combustion air openings sized according to the appliance input rating and the volume of the space, often using the two-opening method or a louvered door. Sealing the closet without air openings can cause incomplete combustion and carbon monoxide production.

Question 42Fixtures, Fixture Fittings, and Water Heaters

A water heater's flue is being connected to a masonry chimney. Which requirement applies to the vent connector?

  1. The connector must slope upward toward the chimney at not less than 1/4 inch per foot Correct answer.
  2. The connector must be installed level to prevent turbulence
  3. The connector must include a barometric damper regardless of appliance listing
  4. The connector must slope downward toward the chimney to drain condensate

Explanation

Vent connectors must slope upward toward the chimney at a minimum of 1/4 inch per foot so flue gases rise and any condensate drains back toward the appliance. A downward or level slope can trap gases and condensate.

Question 43Fixtures, Fixture Fittings, and Water Heaters

A drinking fountain is installed in a public building. What is the required drinking fountain height for accessibility?

  1. A fountain mounted at 30 inches above the floor with a wall-hung design
  2. A single fountain mounted at 36 inches above the floor
  3. A fountain mounted at 48 inches above the floor with no knee clearance
  4. At least one fountain with a spout height of 36 inches maximum and knee clearance for a forward approach Correct answer.

Explanation

Accessible drinking fountains must have a spout height no higher than 36 inches and provide knee and toe clearance for a forward approach. Where two heights are provided, the lower unit serves wheelchair users and the higher unit serves standing users.

Question 44Fixtures, Fixture Fittings, and Water Heaters

A commercial kitchen is being equipped with a pre-rinse spray valve. What maximum flow rate applies to the valve?

  1. 1.28 gallons per minute Correct answer.
  2. 1.6 gallons per minute
  3. 2.5 gallons per minute
  4. 2.2 gallons per minute

Explanation

Pre-rinse spray valves in commercial kitchens are limited to 1.28 gallons per minute at 60 psi. This is a separate category from faucets and showerheads and is intended to cut hot water use in food service.

Question 45Fixtures, Fixture Fittings, and Water Heaters

A water heater is being installed with a recirculation loop to provide instant hot water. Which control strategy best limits energy waste while maintaining hot water at the fixtures?

  1. Removing the check valve from the return line
  2. Continuous pump operation at full speed
  3. Oversizing the water heater to twice the calculated demand
  4. A timer or aquastat that runs the pump only during demand periods Correct answer.

Explanation

Recirculation pumps should be controlled by a timer, aquastat, or demand switch so they run only when hot water is likely needed. Continuous operation wastes energy by keeping the loop hot around the clock.

Question 46Fixtures, Fixture Fittings, and Water Heaters

A fixture is installed with a water-supply connection that must be protected against backflow. Which device is appropriate for a lavatory faucet with a hose-connected spray attachment?

  1. A hose-bibb vacuum breaker Correct answer.
  2. A reduced-pressure principle assembly
  3. A double check valve assembly
  4. An atmospheric vacuum breaker installed downstream of the last control valve

Explanation

A hose-bibb vacuum breaker is the typical device for a faucet with a threaded hose connection, preventing back-siphonage when the outlet is submerged. Higher-hazard connections would call for a reduced-pressure assembly instead.

Question 47Fixtures, Fixture Fittings, and Water Heaters

A water heater is rated at 100,000 BTU/hr input and is installed in a space with a volume of 1,000 cubic feet. Using the standard 50 cubic feet per 1,000 BTU/hr rule, what is the minimum volume required for the space to be considered unconfined?

  1. 1,000 cubic feet
  2. 10,000 cubic feet
  3. 500 cubic feet
  4. 5,000 cubic feet Correct answer.

Explanation

The rule of thumb is 50 cubic feet of space per 1,000 BTU/hr of input, so 100,000 BTU/hr requires 5,000 cubic feet to be treated as unconfined. A 1,000-cubic-foot space is confined and must be provided with combustion air openings.

Question 48Fixtures, Fixture Fittings, and Water Heaters

A water heater's temperature and pressure relief valve is leaking slightly. A technician proposes capping the discharge pipe to stop the drip. Why is this unacceptable?

  1. The cap would increase the flow rate through the valve
  2. The cap would void the water heater warranty only
  3. Capping the discharge prevents the valve from relieving pressure and creates an explosion hazard Correct answer.
  4. The cap would cause the valve to freeze

Explanation

The relief valve discharge must remain open and unobstructed at all times. Capping it disables the safety device, allowing tank pressure to rise until the tank or fittings fail catastrophically.

Question 49Fixtures, Fixture Fittings, and Water Heaters

A lavatory is installed with a faucet that has a 4-inch center set. The drain assembly must be provided with which feature to prevent sewer gas from entering the building?

  1. A drum trap with a vent on the outlet
  2. A trap with a liquid seal of not less than 2 inches and not more than 4 inches Correct answer.
  3. A trap with a liquid seal of 6 inches
  4. A trap primer connected to the drain

Explanation

A fixture trap must maintain a liquid seal of at least 2 inches and not more than 4 inches to block sewer gas while allowing flow. Deeper seals can cause slow drainage and are not permitted for standard fixtures.

Question 50Fixtures, Fixture Fittings, and Water Heaters

A storage water heater is installed in a commercial building. The relief valve discharge pipe must be sized so that it does not restrict the valve's capacity. Which principle governs the discharge pipe sizing?

  1. The discharge pipe may be reduced by one pipe size if the run is short
  2. The discharge pipe must be at least the same nominal diameter as the valve outlet and must not be reduced Correct answer.
  3. The discharge pipe must be two sizes larger than the valve outlet
  4. The discharge pipe size is determined solely by the drain receptor size

Explanation

The relief valve discharge line must be at least the full size of the valve outlet and must not be reduced anywhere along its length. Reducing the pipe would restrict relief capacity and could prevent the valve from relieving pressure fast enough.