ARKANSAS MASTER PLUMBER EXAM READY - VERIFIED QUESTIONS AND
ANSWERS - COMPREHENSIVE LATEST VERSION 2026/2027
Arkansas State Plumbing Code
1. What is the minimum slope required for horizontal drainage pipe 3 inches and smaller?
A) 1/8 inch per foot
✔ B) 1/4 inch per foot
C) 1/2 inch per foot
D) 3/8 inch per foot
Explanation: Pipes 3 inches and smaller require a minimum slope of 1/4 inch per foot
to ensure proper drainage.
2. What is the minimum trap seal depth required by the Arkansas Plumbing Code?
A) 1 inch
✔ B) 2 inches
C) 3 inches
D) 4 inches
Explanation: The minimum trap seal depth is 2 inches, which prevents sewer gases
from entering the building.
3. Which of the following is NOT an approved material for water service pipe?
A) Copper
B) PVC
✔ C) Lead
, D) CPVC
Explanation: Lead pipe is prohibited for water service due to health hazards. Copper,
PVC, and CPVC are all approved.
4. What is the maximum distance a P-trap can be located from its vent?
A) 2 feet
✔ B) 4 feet
C) 6 feet
D) 8 feet
Explanation: A P-trap must be located within 4 feet of its vent connection to maintain
the trap seal.
5. What is the minimum size of the building sewer required for a residence?
A) 2 inches
B) 3 inches
✔ C) 4 inches
D) 6 inches
Explanation: The minimum building sewer size for residential use is 4 inches per
Arkansas Plumbing Code.
6. Which type of pipe is NOT permitted for DWV systems above ground indoors?
A) PVC
B) ABS
C) Cast iron
✔ D) Galvanized steel
Explanation: Galvanized steel is not approved for DWV use above ground indoors
due to corrosion concerns.
7. What is the required air gap for a dishwasher discharge?
, A) Equal to supply pipe diameter
B) 1 inch minimum
✔ C) 2 times the diameter of the inlet
D) Double the effective opening
Explanation: An air gap must be at least twice the diameter of the effective opening of
the supply pipe.
8. What pressure relief valve is required on all water heaters?
A) Pressure only valve
✔ B) Temperature and pressure relief valve
C) Thermal expansion valve
D) Vacuum relief valve
Explanation: All water heaters require a T&P relief valve to prevent dangerous
overpressure conditions.
9. What is the minimum water pressure required at plumbing fixtures?
A) 10 psi
B) 15 psi
✔ C) 20 psi
D) 25 psi
Explanation: A minimum of 20 psi is required at all plumbing fixtures for proper
operation.
10. What is the maximum water pressure allowed in a building plumbing system?
A) 60 psi
✔ B) 80 psi
C) 100 psi
D) 125 psi
Explanation: Maximum allowable water pressure is 80 psi. A PRV is required if
incoming pressure exceeds this.
ANSWERS - COMPREHENSIVE LATEST VERSION 2026/2027
Arkansas State Plumbing Code
1. What is the minimum slope required for horizontal drainage pipe 3 inches and smaller?
A) 1/8 inch per foot
✔ B) 1/4 inch per foot
C) 1/2 inch per foot
D) 3/8 inch per foot
Explanation: Pipes 3 inches and smaller require a minimum slope of 1/4 inch per foot
to ensure proper drainage.
2. What is the minimum trap seal depth required by the Arkansas Plumbing Code?
A) 1 inch
✔ B) 2 inches
C) 3 inches
D) 4 inches
Explanation: The minimum trap seal depth is 2 inches, which prevents sewer gases
from entering the building.
3. Which of the following is NOT an approved material for water service pipe?
A) Copper
B) PVC
✔ C) Lead
, D) CPVC
Explanation: Lead pipe is prohibited for water service due to health hazards. Copper,
PVC, and CPVC are all approved.
4. What is the maximum distance a P-trap can be located from its vent?
A) 2 feet
✔ B) 4 feet
C) 6 feet
D) 8 feet
Explanation: A P-trap must be located within 4 feet of its vent connection to maintain
the trap seal.
5. What is the minimum size of the building sewer required for a residence?
A) 2 inches
B) 3 inches
✔ C) 4 inches
D) 6 inches
Explanation: The minimum building sewer size for residential use is 4 inches per
Arkansas Plumbing Code.
6. Which type of pipe is NOT permitted for DWV systems above ground indoors?
A) PVC
B) ABS
C) Cast iron
✔ D) Galvanized steel
Explanation: Galvanized steel is not approved for DWV use above ground indoors
due to corrosion concerns.
7. What is the required air gap for a dishwasher discharge?
, A) Equal to supply pipe diameter
B) 1 inch minimum
✔ C) 2 times the diameter of the inlet
D) Double the effective opening
Explanation: An air gap must be at least twice the diameter of the effective opening of
the supply pipe.
8. What pressure relief valve is required on all water heaters?
A) Pressure only valve
✔ B) Temperature and pressure relief valve
C) Thermal expansion valve
D) Vacuum relief valve
Explanation: All water heaters require a T&P relief valve to prevent dangerous
overpressure conditions.
9. What is the minimum water pressure required at plumbing fixtures?
A) 10 psi
B) 15 psi
✔ C) 20 psi
D) 25 psi
Explanation: A minimum of 20 psi is required at all plumbing fixtures for proper
operation.
10. What is the maximum water pressure allowed in a building plumbing system?
A) 60 psi
✔ B) 80 psi
C) 100 psi
D) 125 psi
Explanation: Maximum allowable water pressure is 80 psi. A PRV is required if
incoming pressure exceeds this.
