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ICC P3 Plumbing Plans Examiner EXAM QUESTIONS AND
CORRECT VERIFIED SOLUTIONS LATEST UPDATE THIS YEAR –
JUST RELEASED
ICC P3 Plumbing Plans Examiner Practice Exam.
100 PRACTICE QUESTIONS WITH RATIONALES
DOMAIN 1: GENERAL REQUIREMENTS & ADMINISTRATION (6%)
QUESTION 1
A large commercial building plan is submitted with a unique rainwater harvesting system that is
not specifically addressed in the IPC. According to IPC Chapter 1, who has the primary authority
to approve this alternative design?
A) The design professional of record
B) The plumbing contractor
C) The code official (building official)
D) The state plumbing board
Correct Answer: C
Rationale: IPC Section 105.2 grants the code official the authority to approve alternative
materials, designs, and methods of construction when they are at least equivalent to the
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prescribed code. While the design professional may propose alternatives, only the code official
can formally approve them .
QUESTION 2
When reviewing submitted plumbing construction documents, which item is the plans examiner
NOT required to verify under IPC 107?
A) Riser diagrams showing pipe sizes
B) Fixture unit calculations
C) The licensed plumber's hourly labor rate
D) The location and size of cleanouts
Correct Answer: C
Rationale: IPC Section 107 requires construction documents to provide sufficient information for
code compliance determination—including piping layout, pipe sizes, fixture units, slopes, and
cleanouts. Labor rates are contractual and outside the code official's review scope .
QUESTION 3
What is the minimum depth of cover required for water service pipe installed below grade
according to IPC 305.4?
A) 6 inches below grade
B) 12 inches below grade
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C) 12 inches below the local frost line
D) Either B or C, whichever is greater
Correct Answer: D
Rationale: IPC 305.4.1 requires water service pipe to be installed not less than 12 inches below
grade AND not less than 12 inches below the frost line. The more restrictive requirement
(whichever is deeper) controls .
QUESTION 4
IPC 305.6 requires piping passing under or through a concrete or masonry wall to be protected.
Which detail on a plumbing plan would satisfy this requirement?
A) A pipe sleeve at least two pipe sizes larger than the pipe
B) A solid mortar pack around the pipe
C) A threaded coupling cast into the wall
D) Direct embedment with expansion foam
Correct Answer: A
Rationale: IPC 305.6 requires piping passing through or under walls to be protected from
breakage. A sleeve at least two pipe sizes larger than the pipe is the standard detail, allowing
movement and preventing point loading from differential settlement .
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QUESTION 5
Under IPC 312, what test pressure is required for a DWV system when tested with air?
A) 3 psi for 15 minutes
B) 5 psi for 15 minutes
C) 10 psi for 10 minutes
D) 15 psi for 30 minutes
Correct Answer: B
Rationale: IPC 312.3 allows an air test of the DWV system at 5 psi gauge pressure held for not
less than 15 minutes without any drop in pressure. Water testing uses a 10-foot head instead .
QUESTION 6
When reviewing plans, which of the following is considered an "alternate material" requiring
the code official's approval?
A) Cast iron drainage pipe
B) A proprietary pipe joining system
C) Copper water supply pipe
D) PVC DWV pipe
Correct Answer: B
Rationale: IPC 105.2 allows the code official to approve alternatives to code-prescribed
materials or methods when equivalent performance is demonstrated. Proprietary systems not
specifically listed in the code require this approval.
ICC P3 Plumbing Plans Examiner EXAM QUESTIONS AND
CORRECT VERIFIED SOLUTIONS LATEST UPDATE THIS YEAR –
JUST RELEASED
ICC P3 Plumbing Plans Examiner Practice Exam.
100 PRACTICE QUESTIONS WITH RATIONALES
DOMAIN 1: GENERAL REQUIREMENTS & ADMINISTRATION (6%)
QUESTION 1
A large commercial building plan is submitted with a unique rainwater harvesting system that is
not specifically addressed in the IPC. According to IPC Chapter 1, who has the primary authority
to approve this alternative design?
A) The design professional of record
B) The plumbing contractor
C) The code official (building official)
D) The state plumbing board
Correct Answer: C
Rationale: IPC Section 105.2 grants the code official the authority to approve alternative
materials, designs, and methods of construction when they are at least equivalent to the
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prescribed code. While the design professional may propose alternatives, only the code official
can formally approve them .
QUESTION 2
When reviewing submitted plumbing construction documents, which item is the plans examiner
NOT required to verify under IPC 107?
A) Riser diagrams showing pipe sizes
B) Fixture unit calculations
C) The licensed plumber's hourly labor rate
D) The location and size of cleanouts
Correct Answer: C
Rationale: IPC Section 107 requires construction documents to provide sufficient information for
code compliance determination—including piping layout, pipe sizes, fixture units, slopes, and
cleanouts. Labor rates are contractual and outside the code official's review scope .
QUESTION 3
What is the minimum depth of cover required for water service pipe installed below grade
according to IPC 305.4?
A) 6 inches below grade
B) 12 inches below grade
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C) 12 inches below the local frost line
D) Either B or C, whichever is greater
Correct Answer: D
Rationale: IPC 305.4.1 requires water service pipe to be installed not less than 12 inches below
grade AND not less than 12 inches below the frost line. The more restrictive requirement
(whichever is deeper) controls .
QUESTION 4
IPC 305.6 requires piping passing under or through a concrete or masonry wall to be protected.
Which detail on a plumbing plan would satisfy this requirement?
A) A pipe sleeve at least two pipe sizes larger than the pipe
B) A solid mortar pack around the pipe
C) A threaded coupling cast into the wall
D) Direct embedment with expansion foam
Correct Answer: A
Rationale: IPC 305.6 requires piping passing through or under walls to be protected from
breakage. A sleeve at least two pipe sizes larger than the pipe is the standard detail, allowing
movement and preventing point loading from differential settlement .
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QUESTION 5
Under IPC 312, what test pressure is required for a DWV system when tested with air?
A) 3 psi for 15 minutes
B) 5 psi for 15 minutes
C) 10 psi for 10 minutes
D) 15 psi for 30 minutes
Correct Answer: B
Rationale: IPC 312.3 allows an air test of the DWV system at 5 psi gauge pressure held for not
less than 15 minutes without any drop in pressure. Water testing uses a 10-foot head instead .
QUESTION 6
When reviewing plans, which of the following is considered an "alternate material" requiring
the code official's approval?
A) Cast iron drainage pipe
B) A proprietary pipe joining system
C) Copper water supply pipe
D) PVC DWV pipe
Correct Answer: B
Rationale: IPC 105.2 allows the code official to approve alternatives to code-prescribed
materials or methods when equivalent performance is demonstrated. Proprietary systems not
specifically listed in the code require this approval.
