Page 1 of 114
Florida Plumbing Contractor Exam COMPLETE
QUESTIONS AND DETAILED SOLUTIONS LATEST
UPDATE THIS YEAR-JUST RELEASED
Florida Plumbing Contractor Exam question set, written to your specifications.
First, the actual exam coverage in summarized point form based on the Florida Building Code (FBC -
Plumbing), Florida Administrative Code, business/law, and trade knowledge:
• Florida Building Code (FBC) - Plumbing: Chapter 5 – sanitary drainage, venting, stormwater,
water distribution, fixture sizing, material specifications, slopes, cleanouts, backflow prevention,
cross-connection control, water heaters, temperature-pressure relief valves
• Potable Water Supply Systems: Pipe materials (copper, CPVC, PEX, galvanized), pressure
considerations, water hammer protection, thermal expansion, fixture unit calculations, velocity
limits
• Drainage, Waste, and Vent (DWV) Systems: Trap types and seals, venting requirements, wet
vents, stack sizing, building drains and sewers, septic system design (Chapter 64E-6, FAC), fixture
unit values
• Stormwater Drainage: Roof drains, gutters and downspouts, design rainfall intensity (100-year,
1-hour storm at 4.0 in/hr for Florida), storm sewer piping
• Backflow Prevention and Cross-Connection Control: Air gaps, vacuum breakers, RPZ
assemblies, double check valves, annual testing requirements, high-hazard vs low-hazard
protection
• Water Heaters and Boilers: T&P relief valve discharge piping (termination near floor), clearance
to combustibles, scald protection (anti-scald valves), gas water heater venting
• Gas Piping Systems: Black steel, galvanized steel, CSST, pressure testing, sizing, underground
installation, appliance connectors
• Plumbing Fixtures and Appliances: Toilet (1.28 GPF maximum), lavatory, kitchen sink (minimum
2-inch drain), shower valves, indirect waste receptors, grease interceptors (40% flow capacity)
• Blueprint Reading and Isometric Drawings: Symbols (cleanout = circle with cross inside), dashed
lines (concealed/underground piping), 3D pipe routing, fixture locations, elevation changes
• Florida Business and Law for Plumbers: Licensing (F.S. 489.105), experience requirements (4
years), financial stability/credit reporting, insurance (liability, workers comp), lien law, contracts,
change orders, estimating and bidding
• Safety (OSHA): Trenching and excavation (OSHA 1926.652 - 24-inch clearance from utilities),
confined space, fall protection, PPE, hazard communication
• NFPA and Fire Protection Standards: NFPA 14 (standpipe and hose systems), NFPA 54 (fuel gas
code), backflow for fire sprinkler systems, standpipe installation
1. A plumbing contractor installs a water heater relief valve discharge pipe terminating 12 inches above
the floor. What is the MOST likely code violation?
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A) Pipe diameter too large
B) Discharge termination too high above floor
C) Pipe material incorrect
D) Valve pressure too low
Correct: B – Relief valve discharge pipes must terminate close to the floor (typically 6 inches or less) to
prevent scalding hazards if the valve opens .
2. Which pipe material is MOST commonly approved for residential DWV (drain, waste, vent) systems in
Florida?
A) Black steel
B) PVC (polyvinyl chloride)
C) Copper Type K only
D) Galvanized iron exclusively
Correct: B – PVC is widely approved for drainage, waste, and vent systems due to its durability, ease of
installation, and corrosion resistance .
3. A plumbing contractor discovers a cross-connection between potable and nonpotable water systems.
What is the BEST corrective action?
, Page 3 of 114
A) Increase water pressure
B) Install a backflow prevention device
C) Add a larger drain pipe
D) Reduce vent pipe size
Correct: B – Backflow prevention devices protect the potable water supply from contamination due to
backsiphonage or backpressure .
4. What is the primary purpose of a plumbing vent system?
A) Increase water pressure throughout the building
B) Prevent sewer gas entry and maintain trap seals
C) Heat water pipes in cold climates
D) Drain water faster during heavy usage
Correct: B – Venting equalizes pressure in the drainage system, preventing trap seal siphonage and
blocking sewer gases from entering the building .
5. A building drain has repeated backups. The MOST likely cause is:
A) Excessive venting throughout the system
B) Improper slope (too flat or reverse slope)
, Page 4 of 114
C) Oversized water heater
D) Excess pipe insulation on drain lines
Correct: B – Incorrect slope can cause solids accumulation and poor drainage, leading to frequent
backups .
6. What is the minimum function of a P-trap installed under a plumbing fixture?
A) Increase water flow velocity
B) Prevent sewer gases from entering the building
C) Reduce water pressure in supply lines
D) Heat wastewater before discharge
Correct: B – The water seal in a P-trap blocks sewer gases from migrating into occupied spaces while
allowing wastewater to pass .
7. Which device specifically protects the potable water supply from backsiphonage?
A) Pressure regulator
B) Vacuum breaker
C) Cleanout plug
D) Gate valve
Florida Plumbing Contractor Exam COMPLETE
QUESTIONS AND DETAILED SOLUTIONS LATEST
UPDATE THIS YEAR-JUST RELEASED
Florida Plumbing Contractor Exam question set, written to your specifications.
First, the actual exam coverage in summarized point form based on the Florida Building Code (FBC -
Plumbing), Florida Administrative Code, business/law, and trade knowledge:
• Florida Building Code (FBC) - Plumbing: Chapter 5 – sanitary drainage, venting, stormwater,
water distribution, fixture sizing, material specifications, slopes, cleanouts, backflow prevention,
cross-connection control, water heaters, temperature-pressure relief valves
• Potable Water Supply Systems: Pipe materials (copper, CPVC, PEX, galvanized), pressure
considerations, water hammer protection, thermal expansion, fixture unit calculations, velocity
limits
• Drainage, Waste, and Vent (DWV) Systems: Trap types and seals, venting requirements, wet
vents, stack sizing, building drains and sewers, septic system design (Chapter 64E-6, FAC), fixture
unit values
• Stormwater Drainage: Roof drains, gutters and downspouts, design rainfall intensity (100-year,
1-hour storm at 4.0 in/hr for Florida), storm sewer piping
• Backflow Prevention and Cross-Connection Control: Air gaps, vacuum breakers, RPZ
assemblies, double check valves, annual testing requirements, high-hazard vs low-hazard
protection
• Water Heaters and Boilers: T&P relief valve discharge piping (termination near floor), clearance
to combustibles, scald protection (anti-scald valves), gas water heater venting
• Gas Piping Systems: Black steel, galvanized steel, CSST, pressure testing, sizing, underground
installation, appliance connectors
• Plumbing Fixtures and Appliances: Toilet (1.28 GPF maximum), lavatory, kitchen sink (minimum
2-inch drain), shower valves, indirect waste receptors, grease interceptors (40% flow capacity)
• Blueprint Reading and Isometric Drawings: Symbols (cleanout = circle with cross inside), dashed
lines (concealed/underground piping), 3D pipe routing, fixture locations, elevation changes
• Florida Business and Law for Plumbers: Licensing (F.S. 489.105), experience requirements (4
years), financial stability/credit reporting, insurance (liability, workers comp), lien law, contracts,
change orders, estimating and bidding
• Safety (OSHA): Trenching and excavation (OSHA 1926.652 - 24-inch clearance from utilities),
confined space, fall protection, PPE, hazard communication
• NFPA and Fire Protection Standards: NFPA 14 (standpipe and hose systems), NFPA 54 (fuel gas
code), backflow for fire sprinkler systems, standpipe installation
1. A plumbing contractor installs a water heater relief valve discharge pipe terminating 12 inches above
the floor. What is the MOST likely code violation?
, Page 2 of 114
A) Pipe diameter too large
B) Discharge termination too high above floor
C) Pipe material incorrect
D) Valve pressure too low
Correct: B – Relief valve discharge pipes must terminate close to the floor (typically 6 inches or less) to
prevent scalding hazards if the valve opens .
2. Which pipe material is MOST commonly approved for residential DWV (drain, waste, vent) systems in
Florida?
A) Black steel
B) PVC (polyvinyl chloride)
C) Copper Type K only
D) Galvanized iron exclusively
Correct: B – PVC is widely approved for drainage, waste, and vent systems due to its durability, ease of
installation, and corrosion resistance .
3. A plumbing contractor discovers a cross-connection between potable and nonpotable water systems.
What is the BEST corrective action?
, Page 3 of 114
A) Increase water pressure
B) Install a backflow prevention device
C) Add a larger drain pipe
D) Reduce vent pipe size
Correct: B – Backflow prevention devices protect the potable water supply from contamination due to
backsiphonage or backpressure .
4. What is the primary purpose of a plumbing vent system?
A) Increase water pressure throughout the building
B) Prevent sewer gas entry and maintain trap seals
C) Heat water pipes in cold climates
D) Drain water faster during heavy usage
Correct: B – Venting equalizes pressure in the drainage system, preventing trap seal siphonage and
blocking sewer gases from entering the building .
5. A building drain has repeated backups. The MOST likely cause is:
A) Excessive venting throughout the system
B) Improper slope (too flat or reverse slope)
, Page 4 of 114
C) Oversized water heater
D) Excess pipe insulation on drain lines
Correct: B – Incorrect slope can cause solids accumulation and poor drainage, leading to frequent
backups .
6. What is the minimum function of a P-trap installed under a plumbing fixture?
A) Increase water flow velocity
B) Prevent sewer gases from entering the building
C) Reduce water pressure in supply lines
D) Heat wastewater before discharge
Correct: B – The water seal in a P-trap blocks sewer gases from migrating into occupied spaces while
allowing wastewater to pass .
7. Which device specifically protects the potable water supply from backsiphonage?
A) Pressure regulator
B) Vacuum breaker
C) Cleanout plug
D) Gate valve
