I85PREP
⌘ K
ICC P2 study materials
ICC P2 study resources

ICC P2 practice questions

One question at a time. Build your ICC P2 understanding.

First 50 of 200 questions. Each one lists the choices, the correct answer, and an explanation. The checker at the top of this page saves progress in this browser when it is available.

Continue in the practice tool above to load more questions, 50 at a time.

Question 1Administration, General Provisions, and Definitions

Under the plumbing code, a fixture or appliance that is "readily accessible" is one that has which type of access?

  1. Access that requires the removal of an access panel, door or similar obstruction
  2. Access limited to the building maintenance staff
  3. Access restricted to the code official during scheduled inspections
  4. Direct access without removing any panel or door Correct answer.

Explanation

The code distinguishes "accessible" from "readily accessible." Readily accessible means direct access without the necessity of removing any panel, door or similar obstruction. Access requiring removal of a panel or door satisfies only the broader "accessible" standard.

Question 2Administration, General Provisions, and Definitions

In the plumbing code, the word "shall" indicates that a provision is:

  1. Mandatory Correct answer.
  2. Recommended but not required
  3. Permitted at the installer's discretion
  4. Suggested as a best practice

Explanation

The code's definition of terms states that "shall" is mandatory and "should" is advisory. Provisions using "shall" must be complied with as a condition of approval.

Question 3Administration, General Provisions, and Definitions

Which of the following installations requires a plumbing permit?

  1. Clearing a stoppage in a building drain
  2. Removing and reinstalling a water closet in its original location
  3. Repairing a leak in a water supply valve
  4. Installing an additional lavatory in an existing bathroom Correct answer.

Explanation

The permit exemptions cover clearing stoppages, repairing leaks in pipes, valves and fixtures, and removing and reinstalling a water closet where no piping is replaced or rearranged. Adding a new fixture to the system is regulated work that requires a permit.

Question 4Administration, General Provisions, and Definitions

A stop work order issued by the code official must be:

  1. Posted only at the property line
  2. Effective only after the board of appeals reviews it
  3. In writing Correct answer.
  4. Given verbally and confirmed by mail within 10 days

Explanation

The code requires the stop work order to be in writing and to be given to the owner, the owner's agent or the person performing the work. The cited work must stop immediately upon issuance, without awaiting review by any board.

Question 5Administration, General Provisions, and Definitions

The plumbing code defines the flood level rim of a receptacle as:

  1. The highest point of a trap seal
  2. The edge of the receptacle from which water overflows Correct answer.
  3. The elevation of the lowest opening of a fixture drainpipe
  4. The top of the fixture bowl

Explanation

Flood level rim is the edge of the receptacle from which water overflows. That elevation is the reference point for measuring air gaps and for setting indirect waste connections.

Question 6Administration, General Provisions, and Definitions

In the plumbing code, "potable water" is best described as:

  1. Water that is clear and free of visible sediment but may contain bacteria
  2. Water free of impurities that could cause disease or harmful health effects Correct answer.
  3. Water that has been treated by a filtration device, whether or not it has been disinfected
  4. Water delivered through a public water main, regardless of its quality

Explanation

Potable water is water free from impurities present in amounts sufficient to cause disease or harmful physiological effects. It must also meet the bacteriological and chemical quality requirements of the health authority having jurisdiction.

Question 7Administration, General Provisions, and Definitions

Work that will be concealed within the building construction shall not be covered until it has been:

  1. Inspected and approved Correct answer.
  2. Tested for at least 24 hours
  3. Accepted by the general contractor
  4. Photographed and documented

Explanation

The code prohibits concealing regulated work until the code official has inspected and approved it. The permit holder must notify the code official when work is ready for inspection.

Question 8Administration, General Provisions, and Definitions

Plumbing lawfully installed under an earlier edition of the code may continue in use provided that it is:

  1. Maintained in a safe and sanitary condition Correct answer.
  2. Covered by a new permit issued for the existing system
  3. Inspected and certified by a registered design professional each year
  4. Brought into full compliance with the current code when occupancy changes

Explanation

Existing installations that complied with the code in effect at the time of installation may remain in service if they are maintained in a safe and sanitary condition. Full retroactive compliance is not mandated solely because a new edition has been adopted.

Question 9Administration, General Provisions, and Definitions

A plumbing permit becomes invalid if the work authorized by the permit has not commenced within how many days after the permit is issued?

  1. 90 days
  2. 30 days
  3. 180 days Correct answer.
  4. 365 days

Explanation

The code provides that a permit becomes invalid unless the authorized work has commenced within 180 days after issuance. The same 180-day period applies where work is suspended or abandoned after it has begun.

Question 10Administration, General Provisions, and Definitions

An application for appeal of a decision of the code official must be filed within how many days after the decision is filed in the official's office?

  1. 45 days
  2. 20 days Correct answer.
  3. 30 days
  4. 10 days

Explanation

A person entitled to appeal must file an application for appeal within 20 days after the code official's decision is filed in that office. Filing later generally forfeits the right to board review.

Question 11Administration, General Provisions, and Definitions

Which statement best describes the authority of the board of appeals?

  1. It may hear appeals but cannot waive code requirements Correct answer.
  2. It may grant a variance for any hardship shown by the owner
  3. It may waive any code requirement when compliance would be impractical
  4. It may amend the code to fit local building conditions

Explanation

The board of appeals reviews decisions of the code official, but it is not empowered to waive requirements of the code. Relief from a code requirement must come through the code adoption process, not the appeal board.

Question 12Administration, General Provisions, and Definitions

The building drain ends and the building sewer begins at which point?

  1. The exterior face of the foundation wall
  2. 2 feet outside the building wall
  3. 30 inches outside the building wall Correct answer.
  4. The property line

Explanation

The building drain is the lowest piping of the drainage system inside the building; it conveys discharge to the building sewer, which begins 30 inches (762 mm) outside the building wall. The building sewer then carries the discharge to a public sewer or other point of disposal.

Question 13Administration, General Provisions, and Definitions

A drain from a fixture discharges into a receptor at a point below the receptor's flood level rim but above the trap seal. This arrangement is a:

  1. Vacuum breaker
  2. Backwater valve
  3. Air gap
  4. Air break Correct answer.

Explanation

An air break is a drainage connection that terminates below the flood level rim of the receptor and above its trap seal, providing indirect drainage. An air gap, by contrast, is an unobstructed vertical distance through the free atmosphere in a water supply connection.

Question 14Administration, General Provisions, and Definitions

In the plumbing code, a backwater valve is:

  1. A valve that closes automatically to stop the water flow to a fixture
  2. A device that prevents backflow in a potable water line
  3. A device that prevents sewage backflow in a drainage system Correct answer.
  4. A valve that relieves negative pressure in a vent stack

Explanation

A backwater valve is installed in a drainage system to prevent the backflow of sewage. Devices that protect potable water from reversal of flow are backflow preventers, not backwater valves.

Question 15Administration, General Provisions, and Definitions

Under the code, the code official is authorized to enter a premises to make an inspection:

  1. At reasonable times, upon presenting proper credentials Correct answer.
  2. Only during the hours the owner specifies
  3. Only when the owner is present
  4. Only with a court order in all circumstances

Explanation

The code official may enter a premises at reasonable times to inspect or to enforce the code, after presenting proper identification. If entry is refused, the official may pursue the remedies provided by law.

Question 16Administration, General Provisions, and Definitions

A water supply pipe must run through an unheated crawl space. Under the code, the pipe is permitted there only if it is:

  1. Installed below the floor joists
  2. Insulated with a jacket and a continuous interior vapor barrier
  3. Protected from freezing by insulation, heat or both Correct answer.
  4. Of copper or PEX material

Explanation

Water, soil and waste pipes shall not be installed in exterior walls, attics, crawl spaces or other locations subject to freezing unless protected by insulation, heat or both. The material of the pipe does not remove the need for freeze protection.

Question 17Administration, General Provisions, and Definitions

A pipe is run through a bored hole in a wood stud, and the hole is 1 inch from the nearest edge of the stud. What does the code require?

  1. The annular space around the pipe must be filled with an approved sealant
  2. A steel shield plate of at least 1/16-inch thickness Correct answer.
  3. The stud must be replaced with a wider member sized to keep the hole at the center
  4. Nothing is required if the pipe is copper tubing

Explanation

Where concealed piping other than cast-iron or galvanized steel pipe passes through a stud less than 1-1/4 inches from the nearest edge, the pipe must be protected by a steel shield plate. The plate must be at least 0.0575 inch (about 1/16 inch) thick and extend at least 4 inches above sole plates and below top plates.

Question 18Administration, General Provisions, and Definitions

Which statement best describes the code requirement for cutting or notching structural members to make room for piping?

  1. Members may be bored anywhere as long as the pipe is sleeved
  2. Only floor joists may be altered, and only with a shield plate
  3. Any member may be notched up to one-quarter of its depth without approval
  4. Alterations that impair structural strength require approval Correct answer.

Explanation

Structural members shall not be cut, notched, drilled, spliced or otherwise altered in a way that impairs their structural strength without approval. Piping must be routed or the member reinforced so that the building's structural integrity is maintained.

Question 19Administration, General Provisions, and Definitions

Where the bottom of a trench forms the bed for a pipe, the code requires that the pipe:

  1. Be supported on concrete blocks at intervals
  2. Rest on a compacted sand cushion not less than 12 inches deep
  3. Rest on firm, solid ground Correct answer.
  4. Be surrounded by crushed stone to the full trench depth

Explanation

Where piping is laid directly on the trench bottom, the bottom must be firm and solid ground. The pipe is not permitted to rest on blocks, which concentrate loads and can crack or deform it.

Question 20Administration, General Provisions, and Definitions

When approving an alternate material or method of construction, the code official must find that it is:

  1. Designed by a registered design professional
  2. Less costly than the prescribed material or method
  3. Listed and labeled by a nationally recognized testing agency acceptable to the code official
  4. At least equivalent in quality, strength, effectiveness and safety Correct answer.

Explanation

The code official may approve alternate materials, designs and methods of construction where they are found to be at least equivalent to the prescribed requirements in quality, strength, effectiveness, fire resistance, durability and safety. Cost and designer qualifications are not the test.

Question 21Administration, General Provisions, and Definitions

According to the code definitions, a bathroom group consists of:

  1. A water closet, a lavatory, a kitchen sink and a dishwasher
  2. A water closet, one or two lavatories, and a bathtub, a shower, or both Correct answer.
  3. Two or more similar adjacent fixtures discharging into a common branch
  4. All the fixtures on one floor served by a single vertical stack

Explanation

A bathroom group is defined as a water closet, one or two lavatories, and either a bathtub, a shower, or both. The term is used in fixture-count and drainage-loading provisions.

Question 22Administration, General Provisions, and Definitions

The trap seal is measured as the vertical distance between the:

  1. Crown weir and the top of the trap dip Correct answer.
  2. Trap inlet and the building drain invert
  3. Flood level rim and the trap outlet
  4. Fixture outlet and the vent connection

Explanation

The trap seal is the vertical distance between the crown weir and the top of the dip of the trap. That liquid seal is what prevents sewer gas from entering the building.

Question 23Administration, General Provisions, and Definitions

A vertical vent pipe installed primarily to provide circulation of air to and from any part of the drainage system is called a:

  1. Stack vent
  2. Individual vent
  3. Branch vent
  4. Vent stack Correct answer.

Explanation

A vent stack is a vertical vent pipe installed primarily to provide air circulation to and from the drainage system. A stack vent is different: it is the extension of a soil or waste stack above the highest horizontal drain connected to that stack.

Question 24Administration, General Provisions, and Definitions

Which of the following is classified as gray water under the code definitions?

  1. Waste water from a dishwasher
  2. Waste water from a bathtub or shower Correct answer.
  3. Waste water discharged from a water closet or similar fixture
  4. Waste water from a kitchen sink

Explanation

Gray water is waste water discharged from lavatories, bathtubs, showers, clothes washers and laundry sinks. Kitchen sinks, dishwashers and water closets are excluded because of their higher contamination levels.

Question 25Administration, General Provisions, and Definitions

If an owner refuses to allow the code official to enter and inspect the premises, the code official is authorized to:

  1. Seek a warrant or other remedy provided by law Correct answer.
  2. Enter the premises by force at any time without a warrant
  3. Revoke the permit and order the water service disconnected
  4. Permanently close the permit and prohibit future work

Explanation

Where entry is refused, the code official may seek a search warrant or pursue other legal remedies to secure entry. The code does not authorize self-help entry or automatic penalties for a refused inspection.

Question 26Administration, General Provisions, and Definitions

In the plumbing code, the term "approved" means:

  1. manufactured in the United States
  2. acceptable to the code official Correct answer.
  3. listed by a testing laboratory
  4. installed by a licensed contractor

Explanation

The code defines "approved" as acceptable to the code official. Approval is a determination made by the authority enforcing the code, not by a testing agency, contractor, or country of origin.

Question 27Administration, General Provisions, and Definitions

"Listed" equipment or materials are those that appear in a list published by:

  1. the building owner's insurer
  2. an approved agency that performs periodic evaluation Correct answer.
  3. the manufacturer's catalog without third-party evaluation
  4. the local plumbing contractor association

Explanation

Listing requires publication by an organization acceptable to the code official that evaluates products or services and maintains periodic inspection or evaluation. A manufacturer's own catalog or a trade association alone does not satisfy that definition.

Question 28Administration, General Provisions, and Definitions

In the code, the word "shall" is used to indicate:

  1. an optional practice
  2. a mandatory requirement Correct answer.
  3. a recommendation
  4. an exception that may be applied

Explanation

The code uses "shall" for requirements that are mandatory and "may" for provisions that are permissive. This distinction controls whether a provision must be followed or is optional.

Question 29Administration, General Provisions, and Definitions

Plumbing work that requires a permit may begin only after:

  1. the contractor has scheduled an inspection
  2. the plans have been filed with the building owner
  3. the permit has been issued Correct answer.
  4. the material has been delivered

Explanation

A permit must be obtained before the regulated work is started. Delivery of materials, scheduling an inspection, or giving plans to the owner does not authorize commencement of work.

Question 30Administration, General Provisions, and Definitions

The code official is authorized to suspend or revoke a plumbing permit when the permit was issued:

  1. before the contractor paid the fee in full
  2. on the basis of incorrect or incomplete information Correct answer.
  3. during a declared local emergency
  4. after the plans were reviewed by another jurisdiction

Explanation

A permit may be suspended or revoked when it was issued in error, on incorrect or incomplete information, or in violation of the code or an ordinance. The other listed circumstances do not by themselves provide grounds for revocation.

Question 31Administration, General Provisions, and Definitions

When the code official finds plumbing work being performed in a manner contrary to the code, the code official is authorized to:

  1. assess a criminal penalty without notice
  2. complete the work
  3. revoke the contractor's license
  4. issue a written stop work order Correct answer.

Explanation

The code authorizes the code official to issue a stop work order when regulated work is contrary to the code or is dangerous or unsafe. The order must be in writing and states the reason the work must cease.

Question 32Administration, General Provisions, and Definitions

After plumbing work is completed, the permit holder shall:

  1. submit a notarized statement that the work complies
  2. wait for the next scheduled annual inspection
  3. notify the code official for a final inspection Correct answer.
  4. remove the permit from the premises

Explanation

The permit holder must notify the code official when the work is complete so that a final inspection can be made. A notarized statement does not replace the required inspection.

Question 33Administration, General Provisions, and Definitions

The code requires the plumbing system to be tested:

  1. only if the code official suspects a leak
  2. to prove it is watertight and defect-free Correct answer.
  3. only after the building is occupied
  4. only when the owner requests it

Explanation

Testing is required to show that the piping and joints are watertight and free from defects before the system is placed in service or concealed. Testing is not limited to cases where the owner requests it or a leak is suspected.

Question 34Administration, General Provisions, and Definitions

Under the code definitions, a cross connection is a connection between:

  1. two adjacent fixture drains
  2. a vent pipe and a drain pipe
  3. a storm sewer and a sanitary sewer
  4. potable water and a contamination source Correct answer.

Explanation

A cross connection is any connection or arrangement through which nonpotable or contaminated water or other substances could enter the potable water supply. It is a water-supply protection concept, not a drainage or venting arrangement.

Question 35Administration, General Provisions, and Definitions

An air admittance valve is a device that:

  1. measures the flow of water in a drainage pipe
  2. permits sewer gas to escape from the drainage system
  3. prevents backflow in a potable water line
  4. admits air to the drain but blocks gas escape Correct answer.

Explanation

An air admittance valve allows air to enter the drainage system to equalize pressure but does not allow air or sewer gas to escape from the system. It operates as a one-way air inlet.

Question 36Administration, General Provisions, and Definitions

The flood level rim of a plumbing fixture or receptor is the:

  1. level of the fixture's overflow drain
  2. highest point of the trap seal
  3. bottom of the fixture outlet
  4. edge from which water overflows Correct answer.

Explanation

The flood level rim is the edge of the fixture or receptor at which water would overflow onto the floor. It is used in provisions governing fixture connections, backflow protection, and air gaps.

Question 37Administration, General Provisions, and Definitions

In plumbing, "developed length" is measured along the:

  1. straight-line horizontal distance between two points
  2. outside diameter of the pipe
  3. vertical rise of the building
  4. centerline of the pipe and fittings Correct answer.

Explanation

Developed length follows the actual path of the piping, measured along the centerline of the pipe and fittings. It is not a simple straight-line distance between endpoints.

Question 38Administration, General Provisions, and Definitions

A plumbing permit and approved plans have been issued for a new commercial building. During rough-in, the inspector finds that the plans omitted a required vent. Which statement is correct?

  1. The permit is automatically void and all work must stop permanently.
  2. Approved plans do not authorize code violations; the vent must be added. Correct answer.
  3. Because the plans were approved, the omitted vent is not required.
  4. The contractor may complete the work and add the vent after the final inspection.

Explanation

Approval of plans and issuance of a permit do not relieve the permit holder from complying with the code. If the approved documents omit a required component, the work must be corrected to meet the code.

Question 39Administration, General Provisions, and Definitions

A contractor proposes to install used plumbing fixtures removed from another building. Under the code, used equipment and materials are permitted:

  1. only when approved by the code official Correct answer.
  2. if they are installed in a single-family dwelling
  3. whenever the owner signs a waiver
  4. if they are the same brand as new fixtures

Explanation

Used or reclaimed materials and equipment may be used only when approved by the code official, who must determine that they are suitable and comply with code requirements. Brand matching, owner waivers, or building type do not replace that approval.

Question 40Administration, General Provisions, and Definitions

A building is being constructed on a lot adjacent to a public sewer. The code generally requires the building sewer to:

  1. be abandoned until the building is occupied
  2. discharge to a storm sewer instead
  3. connect to the public sewer Correct answer.
  4. discharge to a private sewage disposal system if less expensive

Explanation

Where a public sewer is available, the building sewer is required to connect to it. A private sewage disposal system is not an acceptable substitute merely because it costs less.

Question 41Fixtures, Fixture Fittings, and Water Heaters

What is the minimum required width of a water closet compartment?

  1. 24 inches
  2. 36 inches
  3. 32 inches
  4. 30 inches Correct answer.

Explanation

The plumbing code requires a water closet compartment to be not less than 30 inches in width and not less than 60 inches in depth for floor-mounted water closets. Compartments must provide enough space for use and cleaning without the bowl being obstructed.

Question 42Fixtures, Fixture Fittings, and Water Heaters

The centerline of a water closet shall be located not less than what distance from a side wall or partition?

  1. 18 inches
  2. 15 inches Correct answer.
  3. 12 inches
  4. 24 inches

Explanation

Water closets must be set so that the centerline is at least 15 inches from any side wall or partition, which provides shoulder and elbow room for the user. This clearance is measured from the centerline of the fixture, not from its edge.

Question 43Fixtures, Fixture Fittings, and Water Heaters

A fixture trap must maintain a liquid seal of what depth?

  1. 2 inches to 6 inches
  2. 4 inches to 8 inches
  3. 1 inch to 3 inches
  4. 2 inches to 4 inches Correct answer.

Explanation

Each trap must have a liquid seal of not less than 2 inches and not more than 4 inches. The minimum prevents sewer gas from passing, while the maximum limits the weight of seal water and the chance of siphonage.

Question 44Fixtures, Fixture Fittings, and Water Heaters

How is the required clearance between a water heater and combustible construction determined?

  1. By a fixed 18 inches above the flue collar of the appliance
  2. A fixed 6-inch clearance applies on all sides regardless of the product
  3. By the clearances stated in the listing and the manufacturer's installation instructions Correct answer.
  4. By a fixed 12-inch clearance at the top and 6 inches at the sides

Explanation

Water heaters are installed with the clearance to combustibles specified in their listing and the manufacturer's installation instructions. Because listed products differ in design insulation and heat shielding, a single generic distance cannot be substituted for the listing.

Question 45Fixtures, Fixture Fittings, and Water Heaters

A drainage fixture unit is best described as which of the following?

  1. A measure of the probable load a fixture imposes on the drainage system Correct answer.
  2. The smallest pipe size permitted to drain a given fixture
  3. The number of fixtures that may connect to a single vent
  4. The volume in gallons that a fixture discharges during one use

Explanation

A drainage fixture unit expresses the probable load-producing effect of a fixture on the drainage system, considering its discharge rate and duration of flow. Fixture units allow dissimilar fixtures to be added together when sizing drains and vents.

Question 46Fixtures, Fixture Fittings, and Water Heaters

What is the minimum set of plumbing fixtures required for a dwelling unit?

  1. One water closet, one lavatory, one bathtub or shower, and one kitchen sink Correct answer.
  2. One water closet, one lavatory, one bathtub or shower, and one laundry sink
  3. One water closet, one lavatory, and one kitchen sink
  4. Two water closets, one lavatory, and one bathtub or shower

Explanation

The minimum facilities table requires each dwelling unit to have a water closet, a lavatory, a bathtub or shower, and a kitchen sink. Additional fixtures are installed by choice or by other code provisions, not as a minimum.

Question 47Fixtures, Fixture Fittings, and Water Heaters

Every storage-type water heater must be equipped with which of the following protective devices?

  1. A vacuum relief valve
  2. A pressure-reducing valve
  3. An expansion tank
  4. A temperature and pressure relief valve Correct answer.

Explanation

Storage water heaters are required to be protected by a temperature and pressure relief valve that limits both excessive temperature and excessive pressure in the tank. The device must be listed and rated for the appliance and must discharge to a safe place.

Question 48Fixtures, Fixture Fittings, and Water Heaters

What is the minimum size of the trap and fixture drain serving a water closet?

  1. 3 inches Correct answer.
  2. 4 inches
  3. 1-1/2 inches
  4. 2 inches

Explanation

The minimum fixture drain and trap size for a water closet is 3 inches, which accommodates the solids and the rapid discharge of a flush. Smaller sizes are permitted only for fixtures with lower solids loading.

Question 49Fixtures, Fixture Fittings, and Water Heaters

How must the discharge pipe from a temperature and pressure relief valve be sized?

  1. Not less in size than the valve outlet, with no reduction anywhere in the run Correct answer.
  2. One nominal size smaller than the valve outlet to increase velocity
  3. Reduced at the point of discharge to control the flow
  4. Sized to match the receptor or floor drain into which it discharges

Explanation

The relief valve discharge pipe must be at least the full size of the valve outlet and must not be reduced anywhere along its length. Full size maintains the valve's rated discharge capacity so pressure cannot build in the tank.

Question 50Fixtures, Fixture Fittings, and Water Heaters

Where must the discharge from a temperature and pressure relief valve terminate?

  1. Into a floor drain connected by a trap
  2. Directly into the building drain
  3. Into the drain line serving the water heater drain pan
  4. Through an air gap or air break to an indirect waste receptor, or to the outside Correct answer.

Explanation

Relief valve discharge is an indirect waste and must terminate through an air gap or air break into an indirect waste receptor, or discharge to the outside of the building. The discharge must be visible and must not create a cross-connection with the drainage system.