ARIZONA C 37 AND CR 37 PLUMBING
CONTRACTOR LICENSE EXAM PREP
DETAILED CORRECT ANSWERS WITH
RATIONALES GRADE A+ VERIFIED |
100% PASS GUARANTEE
Arizona C-37 (CR-37) Plumbing Contractor Practice Exam
1. A commercial commercial kitchen project requires the installation
of a grease interceptor to handle high-temperature, grease-laden
wastewater from commercial dishwashers and pot sinks. According
to the International Plumbing Code (IPC), what is the minimum
required distance between the interceptor and the fixtures it
serves, and how must the vent be sized to prevent siphonage?
A) The interceptor must be placed within 5 feet of the fixtures, and
the vent must be a minimum of 1.5 inches.
B) The interceptor must be placed as close as practical to the
fixtures, and the vent must be sized based on the total drainage
fixture unit (DFU) load but not less than 2 inches.
C) The interceptor must be placed as close as practical to
the fixtures served, and the fixture vent must be sized in
accordance with IPC Chapter 9 based on DFU load but
never less than 1.5 inches.
D) The interceptor must be placed at the exterior of the building
footprint only, and the vent must be equal to the size of the outlet
pipe.
Correct Answer: C. Rationale: The IPC mandates
that grease interceptors be placed as close as practical to the
fixtures they serve to prevent grease from cooling and solidifying
in the drainage piping prior to reaching the interceptor. Vents
must be sized based on the fixture unit load, with 1.5 inches being
the standard minimum for individual vents serving such fixtures.
2. An Arizona plumbing contractor is excavating a trench that is 6
feet deep in Type B soil to lay a new 6-inch PVC sewer main.
According to OSHA Subpart P, what specific cave-in protection or
sloping measures must be implemented before any worker enters
the trench?
, A) No protection is required since the trench is less than 10 feet
deep and Type B soil is highly stable.
B) The trench walls must be sloped to a maximum allowable
inclination of 1:1 (45 degrees) or protected by an engineered
shoring system.
C) The trench walls must be protected by an approved
shielding or shoring system, or sloped at an angle of 1
horizontal to 1 vertical (45 degrees) because the depth
exceeds 5 feet.
D) Mechanical ventilation must be provided alongside a simple
benching system with a 2:1 slope profile.
Correct Answer: C. Rationale: OSHA regulations
require cave-in protection for trenches 5 feet or deeper unless the
excavation is entirely in stable rock. For Type B soil, the
maximum allowable slope is 1:1 (45 degrees). Alternatively,
trench shields (trench boxes) or shoring must be utilized.
3. During a rough-in inspection for a multi-story medical office
building, the inspector notes that a 4-inch horizontal drainage pipe
has a slope of 1/8 inch per foot. Under what condition, if any, does
the International Plumbing Code (IPC) permit a 4-inch pipe to be
installed with a 1/8-inch per foot slope?
A) It is never permitted; all drainage piping 4 inches and larger
must maintain a minimum slope of 1/4 inch per foot.
B) It is permitted only if the pipe serves fewer than 10 water closets
and has a cleanout every 50 feet.
C) It is permitted by code only where physical or
structural obstructions make the standard 1/4-inch slope
impossible, and it is approved by the administrative
authority.
D) It is automatically permitted for all drainage piping that is 3
inches or larger in diameter without special approval.
Correct Answer: C. Rationale: The IPC states that the
minimum slope for piping sized 3 inches to 6 inches is 1/4 inch per
foot. However, where physical constraints exist, the
administrative authority may approve a slope of 1/8 inch per foot
for piping 4 inches and larger.
4. A plumbing technician is installing a replacement 50-gallon gas-
fired water heater in a residential garage in Phoenix, Arizona. To
, comply with local code safety regulations regarding potential
flammable vapors, how high above the garage floor must the
ignition source be located?
A) The ignition source must be located at least 12 inches above the
garage floor surface.
B) The ignition source must be located at least 18 inches
above the garage floor surface.
C) The ignition source must be located at least 24 inches above the
garage floor surface to account for heavy vapor pooling.
D) No elevation is required if the water heater is equipped with a
flammable vapor ignition resistant (FVIR) system and certified by
the manufacturer.
Correct Answer: B. Rationale: IPC and National Fuel
Gas Code regulations require that ignition sources of appliances
burning fuel or causing sparks in residential garages be elevated
at least 18 inches above the floor to minimize the risk of igniting
flammable vapors (such as gasoline) that collect near the ground.
5. A commercial C-37 contractor enters into a verbal agreement with
a client to perform a small commercial bathroom remodel for
$1,200. After the work is completed, the client refuses to pay the
full amount, claiming the price was too high. Under Arizona
Registrar of Contractors (ROC) rules, what is the legal status of this
contract?
A) The contract is fully enforceable because Arizona law allows
verbal contracts for any amount under $2,500.
B) The contract is void because all commercial plumbing contracts
in Arizona must be written, regardless of the dollar value.
C) The contract is enforceable, but the contractor may
face disciplinary action from the ROC because all
residential and commercial contracts exceeding $1,000
must be in writing.
D) The contract is voidable at the option of the client only if they
file an official complaint within 30 days of project completion.
Correct Answer: C. Rationale: Arizona ROC rules
state that all agreements for work exceeding $1,000 must be in
writing. While the work may still be legally compensable under
breach of contract theories, the contractor is in violation of
administrative rules and subject to citations.
, 6. While testing a newly installed DWV (Drain, Waste, and Vent)
system in a three-story commercial structure, the contractor elects
to use a water test. According to the IPC, what is the minimum
height of the water column required, and how long must the
system hold the water without leaking?
A) A water column of 5 feet must be established and held for a
minimum duration of 10 minutes.
B) A water column of 10 feet must be established and held
for a minimum duration of 15 minutes.
C) A water column of 15 feet must be established and held for a
minimum duration of 30 minutes.
D) The water column must completely fill the entire system to the
roof line and be held for a minimum of 60 minutes.
Correct Answer: B. Rationale: The IPC specifies that
for a water test on a DWV system, the piping must be filled to a
point at least 10 feet above the section being tested, and it must
hold that pressure for at least 15 minutes without any drop in
water level.
7. A medical facility requires the installation of a dedicated non-
potable water system to supply cooling towers. To prevent
accidental cross-connection, how must the non-potable water
outlets and piping be legally identified in accordance with the
International Plumbing Code?
A) The piping must be painted bright red with white lettering
stating "NON-POTABLE WATER" every 20 feet.
B) The piping and outlets must be permanently identified
with yellow background signage or tape featuring black
lettering stating "NON-POTABLE WATER," or colored
purple for reclaimed water.
C) The piping must be wrapped in solid green plastic sheathing
with warning tags placed at every valve and fitting.
D) No specialized marking is required if the non-potable line uses a
completely different material, such as galvanized steel, while the
potable line uses copper.
Correct Answer: B. Rationale: The IPC requires non-
potable water distribution systems to be specifically identified.
The standard identification involves a yellow background with
black uppercase lettering, or purple marking specifically when
using reclaimed/recycled water sources.
CONTRACTOR LICENSE EXAM PREP
DETAILED CORRECT ANSWERS WITH
RATIONALES GRADE A+ VERIFIED |
100% PASS GUARANTEE
Arizona C-37 (CR-37) Plumbing Contractor Practice Exam
1. A commercial commercial kitchen project requires the installation
of a grease interceptor to handle high-temperature, grease-laden
wastewater from commercial dishwashers and pot sinks. According
to the International Plumbing Code (IPC), what is the minimum
required distance between the interceptor and the fixtures it
serves, and how must the vent be sized to prevent siphonage?
A) The interceptor must be placed within 5 feet of the fixtures, and
the vent must be a minimum of 1.5 inches.
B) The interceptor must be placed as close as practical to the
fixtures, and the vent must be sized based on the total drainage
fixture unit (DFU) load but not less than 2 inches.
C) The interceptor must be placed as close as practical to
the fixtures served, and the fixture vent must be sized in
accordance with IPC Chapter 9 based on DFU load but
never less than 1.5 inches.
D) The interceptor must be placed at the exterior of the building
footprint only, and the vent must be equal to the size of the outlet
pipe.
Correct Answer: C. Rationale: The IPC mandates
that grease interceptors be placed as close as practical to the
fixtures they serve to prevent grease from cooling and solidifying
in the drainage piping prior to reaching the interceptor. Vents
must be sized based on the fixture unit load, with 1.5 inches being
the standard minimum for individual vents serving such fixtures.
2. An Arizona plumbing contractor is excavating a trench that is 6
feet deep in Type B soil to lay a new 6-inch PVC sewer main.
According to OSHA Subpart P, what specific cave-in protection or
sloping measures must be implemented before any worker enters
the trench?
, A) No protection is required since the trench is less than 10 feet
deep and Type B soil is highly stable.
B) The trench walls must be sloped to a maximum allowable
inclination of 1:1 (45 degrees) or protected by an engineered
shoring system.
C) The trench walls must be protected by an approved
shielding or shoring system, or sloped at an angle of 1
horizontal to 1 vertical (45 degrees) because the depth
exceeds 5 feet.
D) Mechanical ventilation must be provided alongside a simple
benching system with a 2:1 slope profile.
Correct Answer: C. Rationale: OSHA regulations
require cave-in protection for trenches 5 feet or deeper unless the
excavation is entirely in stable rock. For Type B soil, the
maximum allowable slope is 1:1 (45 degrees). Alternatively,
trench shields (trench boxes) or shoring must be utilized.
3. During a rough-in inspection for a multi-story medical office
building, the inspector notes that a 4-inch horizontal drainage pipe
has a slope of 1/8 inch per foot. Under what condition, if any, does
the International Plumbing Code (IPC) permit a 4-inch pipe to be
installed with a 1/8-inch per foot slope?
A) It is never permitted; all drainage piping 4 inches and larger
must maintain a minimum slope of 1/4 inch per foot.
B) It is permitted only if the pipe serves fewer than 10 water closets
and has a cleanout every 50 feet.
C) It is permitted by code only where physical or
structural obstructions make the standard 1/4-inch slope
impossible, and it is approved by the administrative
authority.
D) It is automatically permitted for all drainage piping that is 3
inches or larger in diameter without special approval.
Correct Answer: C. Rationale: The IPC states that the
minimum slope for piping sized 3 inches to 6 inches is 1/4 inch per
foot. However, where physical constraints exist, the
administrative authority may approve a slope of 1/8 inch per foot
for piping 4 inches and larger.
4. A plumbing technician is installing a replacement 50-gallon gas-
fired water heater in a residential garage in Phoenix, Arizona. To
, comply with local code safety regulations regarding potential
flammable vapors, how high above the garage floor must the
ignition source be located?
A) The ignition source must be located at least 12 inches above the
garage floor surface.
B) The ignition source must be located at least 18 inches
above the garage floor surface.
C) The ignition source must be located at least 24 inches above the
garage floor surface to account for heavy vapor pooling.
D) No elevation is required if the water heater is equipped with a
flammable vapor ignition resistant (FVIR) system and certified by
the manufacturer.
Correct Answer: B. Rationale: IPC and National Fuel
Gas Code regulations require that ignition sources of appliances
burning fuel or causing sparks in residential garages be elevated
at least 18 inches above the floor to minimize the risk of igniting
flammable vapors (such as gasoline) that collect near the ground.
5. A commercial C-37 contractor enters into a verbal agreement with
a client to perform a small commercial bathroom remodel for
$1,200. After the work is completed, the client refuses to pay the
full amount, claiming the price was too high. Under Arizona
Registrar of Contractors (ROC) rules, what is the legal status of this
contract?
A) The contract is fully enforceable because Arizona law allows
verbal contracts for any amount under $2,500.
B) The contract is void because all commercial plumbing contracts
in Arizona must be written, regardless of the dollar value.
C) The contract is enforceable, but the contractor may
face disciplinary action from the ROC because all
residential and commercial contracts exceeding $1,000
must be in writing.
D) The contract is voidable at the option of the client only if they
file an official complaint within 30 days of project completion.
Correct Answer: C. Rationale: Arizona ROC rules
state that all agreements for work exceeding $1,000 must be in
writing. While the work may still be legally compensable under
breach of contract theories, the contractor is in violation of
administrative rules and subject to citations.
, 6. While testing a newly installed DWV (Drain, Waste, and Vent)
system in a three-story commercial structure, the contractor elects
to use a water test. According to the IPC, what is the minimum
height of the water column required, and how long must the
system hold the water without leaking?
A) A water column of 5 feet must be established and held for a
minimum duration of 10 minutes.
B) A water column of 10 feet must be established and held
for a minimum duration of 15 minutes.
C) A water column of 15 feet must be established and held for a
minimum duration of 30 minutes.
D) The water column must completely fill the entire system to the
roof line and be held for a minimum of 60 minutes.
Correct Answer: B. Rationale: The IPC specifies that
for a water test on a DWV system, the piping must be filled to a
point at least 10 feet above the section being tested, and it must
hold that pressure for at least 15 minutes without any drop in
water level.
7. A medical facility requires the installation of a dedicated non-
potable water system to supply cooling towers. To prevent
accidental cross-connection, how must the non-potable water
outlets and piping be legally identified in accordance with the
International Plumbing Code?
A) The piping must be painted bright red with white lettering
stating "NON-POTABLE WATER" every 20 feet.
B) The piping and outlets must be permanently identified
with yellow background signage or tape featuring black
lettering stating "NON-POTABLE WATER," or colored
purple for reclaimed water.
C) The piping must be wrapped in solid green plastic sheathing
with warning tags placed at every valve and fitting.
D) No specialized marking is required if the non-potable line uses a
completely different material, such as galvanized steel, while the
potable line uses copper.
Correct Answer: B. Rationale: The IPC requires non-
potable water distribution systems to be specifically identified.
The standard identification involves a yellow background with
black uppercase lettering, or purple marking specifically when
using reclaimed/recycled water sources.
