North Carolina Fire Sprinkler Contractor Exam Practice
Questions and Correct Answers with Rationales
Question 1: According to NFPA 13, what is the maximum allowable distance from a wall to the first
sprinkler in a light hazard occupancy with standard spray upright sprinklers, assuming smooth
construction?
A. 3 feet 6 inches B. 7 feet 6 inches C. 5 feet 0 inches D. 6 feet 0 inches
CORRECT ANSWER: B. 7 feet 6 inches
Rationale: In a light hazard occupancy with standard spray sprinklers, the maximum distance from a wall
to the first sprinkler along the branch line is typically one-half of the maximum allowable distance
between sprinklers, which is 15 feet, resulting in 7 feet 6 inches.
Question 2: In accordance with North Carolina fire sprinkler regulations and NFPA 25, how frequently
must a main drain test be performed on a water-based fire protection system?
A. Monthly B. Annually C. Quarterly D. Semi-annually
CORRECT ANSWER: B. Annually
Rationale: NFPA 25 requires that an annual main drain test be conducted at each system riser to verify
that there is no obstruction or significant degradation of the water supply piping.
Question 3: When sizing underground fire service mains using ductile iron pipe, what is the standard
minimum depth of cover required in North Carolina to protect against freezing and mechanical damage?
A. 18 inches B. 24 inches C. 30 inches D. 36 inches
CORRECT ANSWER: C. 30 inches
Rationale: Standard underground fire service main installations typically require a minimum depth of
cover of 30 inches (or below the local frost line) to prevent freezing and protect against surface loads.
Question 4: What is the maximum pressure rating for standard grooved-end couplings typically used in
commercial wet pipe fire sprinkler systems unless specified otherwise by the manufacturer?
A. 175 psi B. 300 psi C. 500 psi D. 250 psi
CORRECT ANSWER: B. 300 psi
Rationale: Most standard commercial grooved-end fittings and flexible couplings manufactured for fire
protection systems are rated for working pressures up to 300 psi, matching high-rise and heavy
commercial demands.
,Question 5: Which NFPA standard governs the installation of stationary pumps for fire protection
systems?
A. NFPA 13 B. NFPA 20 C. NFPA 24 D. NFPA 25
CORRECT ANSWER: B. NFPA 20
Rationale: NFPA 20 is the standard for the installation of stationary pumps for fire protection, covering
centrifugal pumps, positive displacement pumps, and driver requirements.
Question 6: What is the minimum required test pressure for a hydrostatic pressure test on a new fire
sprinkler system piping network carrying normal working pressures below 150 psi?
A. 150 psi for 2 hours B. 200 psi for 2 hours C. 250 psi for 2 hours D. 300 psi for 1 hour
CORRECT ANSWER: B. 200 psi for 2 hours
Rationale: NFPA 13 mandates that system piping must be hydrostatically tested at not less than 200 psi,
or 50 psi in excess of the maximum system pressure, whichever is greater, and maintained for 2 hours
without a drop in pressure.
Question 7: Under NFPA 13, what is the minimum design discharge density for an Ordinary Hazard Group
1 occupancy?
A. 0.10 gpm/sq ft B. 0.15 gpm/sq ft C. 0.20 gpm/sq ft D. 0.25 gpm/sq ft
CORRECT ANSWER: B. 0.15 gpm/sq ft
Rationale: Ordinary Hazard Group 1 occupancies have conditions with moderate to low combustibility,
requiring a minimum design sprinkler discharge density of 0.15 gpm per square foot over the design
area.
Question 8: Which type of backflow preventer is typically required on a fire sprinkler system connected to
a public potable water supply where chemical additives are not used?
A. Double Check Valve Assembly (DCVA) B. Reduced Pressure Principle Assembly (RPPA) C. Atmospheric
Vacuum Breaker (AVB) D. Pressure Vacuum Breaker (PVB)
CORRECT ANSWER: A. Double Check Valve Assembly (DCVA)
Rationale: For fire protection systems without chemical additives or booster pumps injecting non-
potable sources, a Double Check Valve Assembly is standard to prevent backflow into the potable water
supply.
Question 9: What is the minimum hanger size required for supporting steel pipe with a diameter of 2
inches according to NFPA 13 installation standards?
A. 3/8 inch B. 1/2 inch C. 5/8 inch D. 3/4 inch
,CORRECT ANSWER: A. 3/8 inch
Rationale: NFPA 13 specifies that hanger rods for pipe sizes up to 2 inches must have a minimum
diameter of 3/8 inch to ensure adequate structural support under fire conditions.
Question 10: In a pre-action fire sprinkler system, what initiates the opening of the pre-action valve to
allow water to enter the piping network prior to sprinkler fusion?
A. Loss of water pressure in the riser B. Manual activation of a test valve C. A separate detection system
(such as smoke or heat detectors) D. Ambient room temperature reaching 165°F
CORRECT ANSWER: C. A separate detection system (such as smoke or heat detectors)
Rationale: Pre-action systems require a supplemental fire detection system (or manual station) to
actuate the valve and fill the dry piping with water before individual automatic sprinklers open.
Question 11: What is the minimum distance that must be maintained below fire sprinkler deflectors to
ensure unobstructed water distribution pattern development?
A. 6 inches B. 12 inches C. 18 inches D. 24 inches
CORRECT ANSWER: C. 18 inches
Rationale: NFPA 13 requires a minimum clearance of 18 inches below sprinkler deflectors from storage
and structural elements to allow proper spray pattern formation.
Question 12: Which valve type is legally and operationally mandated as the control valve on a fire
sprinkler system riser to ensure it can be easily monitored for a closed position?
A. Globe valve B. Gate valve or Butterfly valve with tamper switch C. Plug valve D. Needle valve
CORRECT ANSWER: B. Gate valve or Butterfly valve with tamper switch
Rationale: Indicating control valves such as Outside Screw and Yoke (OS&Y) gate valves or listed butterfly
valves equipped with tamper switches are required to prevent accidental shut-off of the water supply.
Question 13: According to NFPA 14, what is the maximum allowable residual pressure at the outlet of a
Class I standpipe hose connection when flowing 500 gpm?
A. 65 psi B. 100 psi C. 175 psi D. 100 psi to 175 psi
CORRECT ANSWER: C. 175 psi
Rationale: NFPA 14 limits the maximum pressure at any Class I or Class III hose connection outlet to 175
psi to ensure that firefighters can safely handle and control fire hoses under high pressure.
Question 14: What is the primary purpose of an inspector's test valve installed at the remote extremity of
a fire sprinkler system?
, A. To drain the entire system for maintenance B. To test the water flow alarm device and verify system
flow capability C. To bleed trapped air from high points in the system D. To regulate the municipal water
pressure entering the building
CORRECT ANSWER: B. To test the water flow alarm device and verify system flow capability
Rationale: The inspector's test connection simulates the flow of a single sprinkler head, verifying that the
water flow switch or alarm valve operates correctly within the required time frame.
Question 15: In North Carolina, who is ultimately responsible for ensuring that a fire sprinkler system is
inspected, tested, and maintained in accordance with NFPA 25?
A. The local fire marshal B. The installing contractor C. The property owner or designated representative
D. The municipal water utility provider
CORRECT ANSWER: C. The property owner or designated representative
Rationale: NFPA 25 and local codes place the legal responsibility for the ongoing inspection, testing, and
maintenance of fire protection systems squarely on the property owner or management.
Question 16: What color temperature rating corresponds to a standard commercial fire sprinkler rated
for an ordinary temperature classification of 135°F to 170°F?
A. Uncolored or Black B. Red C. Yellow D. Blue
CORRECT ANSWER: A. Uncolored or Black
Rationale: Standard temperature-rated sprinklers (135°F to 170°F) have glass bulbs that are
clear/colorless or frames that are uncolored, whereas higher temperature ratings use color-coded bulbs
(e.g., red, yellow, green, blue).
Question 17: When calculating hydraulic friction loss using the Hazen-Williams formula, what friction loss
coefficient (C-factor) is mandated for new black steel dry pipe or pre-action sprinkler piping?
A. 100 B. 120 C. 140 D. 150
CORRECT ANSWER: A. 100
Rationale: NFPA 13 specifies a C-factor of 100 for dry pipe and pre-action systems utilizing steel pipe due
to the higher likelihood of internal corrosion and scaling over time.
Question 18: What is the maximum spacing between branch line hangers for 1-inch steel pipe according
to standard NFPA 13 installation rules?
A. 8 feet B. 10 feet C. 12 feet D. 15 feet
CORRECT ANSWER: C. 12 feet
Questions and Correct Answers with Rationales
Question 1: According to NFPA 13, what is the maximum allowable distance from a wall to the first
sprinkler in a light hazard occupancy with standard spray upright sprinklers, assuming smooth
construction?
A. 3 feet 6 inches B. 7 feet 6 inches C. 5 feet 0 inches D. 6 feet 0 inches
CORRECT ANSWER: B. 7 feet 6 inches
Rationale: In a light hazard occupancy with standard spray sprinklers, the maximum distance from a wall
to the first sprinkler along the branch line is typically one-half of the maximum allowable distance
between sprinklers, which is 15 feet, resulting in 7 feet 6 inches.
Question 2: In accordance with North Carolina fire sprinkler regulations and NFPA 25, how frequently
must a main drain test be performed on a water-based fire protection system?
A. Monthly B. Annually C. Quarterly D. Semi-annually
CORRECT ANSWER: B. Annually
Rationale: NFPA 25 requires that an annual main drain test be conducted at each system riser to verify
that there is no obstruction or significant degradation of the water supply piping.
Question 3: When sizing underground fire service mains using ductile iron pipe, what is the standard
minimum depth of cover required in North Carolina to protect against freezing and mechanical damage?
A. 18 inches B. 24 inches C. 30 inches D. 36 inches
CORRECT ANSWER: C. 30 inches
Rationale: Standard underground fire service main installations typically require a minimum depth of
cover of 30 inches (or below the local frost line) to prevent freezing and protect against surface loads.
Question 4: What is the maximum pressure rating for standard grooved-end couplings typically used in
commercial wet pipe fire sprinkler systems unless specified otherwise by the manufacturer?
A. 175 psi B. 300 psi C. 500 psi D. 250 psi
CORRECT ANSWER: B. 300 psi
Rationale: Most standard commercial grooved-end fittings and flexible couplings manufactured for fire
protection systems are rated for working pressures up to 300 psi, matching high-rise and heavy
commercial demands.
,Question 5: Which NFPA standard governs the installation of stationary pumps for fire protection
systems?
A. NFPA 13 B. NFPA 20 C. NFPA 24 D. NFPA 25
CORRECT ANSWER: B. NFPA 20
Rationale: NFPA 20 is the standard for the installation of stationary pumps for fire protection, covering
centrifugal pumps, positive displacement pumps, and driver requirements.
Question 6: What is the minimum required test pressure for a hydrostatic pressure test on a new fire
sprinkler system piping network carrying normal working pressures below 150 psi?
A. 150 psi for 2 hours B. 200 psi for 2 hours C. 250 psi for 2 hours D. 300 psi for 1 hour
CORRECT ANSWER: B. 200 psi for 2 hours
Rationale: NFPA 13 mandates that system piping must be hydrostatically tested at not less than 200 psi,
or 50 psi in excess of the maximum system pressure, whichever is greater, and maintained for 2 hours
without a drop in pressure.
Question 7: Under NFPA 13, what is the minimum design discharge density for an Ordinary Hazard Group
1 occupancy?
A. 0.10 gpm/sq ft B. 0.15 gpm/sq ft C. 0.20 gpm/sq ft D. 0.25 gpm/sq ft
CORRECT ANSWER: B. 0.15 gpm/sq ft
Rationale: Ordinary Hazard Group 1 occupancies have conditions with moderate to low combustibility,
requiring a minimum design sprinkler discharge density of 0.15 gpm per square foot over the design
area.
Question 8: Which type of backflow preventer is typically required on a fire sprinkler system connected to
a public potable water supply where chemical additives are not used?
A. Double Check Valve Assembly (DCVA) B. Reduced Pressure Principle Assembly (RPPA) C. Atmospheric
Vacuum Breaker (AVB) D. Pressure Vacuum Breaker (PVB)
CORRECT ANSWER: A. Double Check Valve Assembly (DCVA)
Rationale: For fire protection systems without chemical additives or booster pumps injecting non-
potable sources, a Double Check Valve Assembly is standard to prevent backflow into the potable water
supply.
Question 9: What is the minimum hanger size required for supporting steel pipe with a diameter of 2
inches according to NFPA 13 installation standards?
A. 3/8 inch B. 1/2 inch C. 5/8 inch D. 3/4 inch
,CORRECT ANSWER: A. 3/8 inch
Rationale: NFPA 13 specifies that hanger rods for pipe sizes up to 2 inches must have a minimum
diameter of 3/8 inch to ensure adequate structural support under fire conditions.
Question 10: In a pre-action fire sprinkler system, what initiates the opening of the pre-action valve to
allow water to enter the piping network prior to sprinkler fusion?
A. Loss of water pressure in the riser B. Manual activation of a test valve C. A separate detection system
(such as smoke or heat detectors) D. Ambient room temperature reaching 165°F
CORRECT ANSWER: C. A separate detection system (such as smoke or heat detectors)
Rationale: Pre-action systems require a supplemental fire detection system (or manual station) to
actuate the valve and fill the dry piping with water before individual automatic sprinklers open.
Question 11: What is the minimum distance that must be maintained below fire sprinkler deflectors to
ensure unobstructed water distribution pattern development?
A. 6 inches B. 12 inches C. 18 inches D. 24 inches
CORRECT ANSWER: C. 18 inches
Rationale: NFPA 13 requires a minimum clearance of 18 inches below sprinkler deflectors from storage
and structural elements to allow proper spray pattern formation.
Question 12: Which valve type is legally and operationally mandated as the control valve on a fire
sprinkler system riser to ensure it can be easily monitored for a closed position?
A. Globe valve B. Gate valve or Butterfly valve with tamper switch C. Plug valve D. Needle valve
CORRECT ANSWER: B. Gate valve or Butterfly valve with tamper switch
Rationale: Indicating control valves such as Outside Screw and Yoke (OS&Y) gate valves or listed butterfly
valves equipped with tamper switches are required to prevent accidental shut-off of the water supply.
Question 13: According to NFPA 14, what is the maximum allowable residual pressure at the outlet of a
Class I standpipe hose connection when flowing 500 gpm?
A. 65 psi B. 100 psi C. 175 psi D. 100 psi to 175 psi
CORRECT ANSWER: C. 175 psi
Rationale: NFPA 14 limits the maximum pressure at any Class I or Class III hose connection outlet to 175
psi to ensure that firefighters can safely handle and control fire hoses under high pressure.
Question 14: What is the primary purpose of an inspector's test valve installed at the remote extremity of
a fire sprinkler system?
, A. To drain the entire system for maintenance B. To test the water flow alarm device and verify system
flow capability C. To bleed trapped air from high points in the system D. To regulate the municipal water
pressure entering the building
CORRECT ANSWER: B. To test the water flow alarm device and verify system flow capability
Rationale: The inspector's test connection simulates the flow of a single sprinkler head, verifying that the
water flow switch or alarm valve operates correctly within the required time frame.
Question 15: In North Carolina, who is ultimately responsible for ensuring that a fire sprinkler system is
inspected, tested, and maintained in accordance with NFPA 25?
A. The local fire marshal B. The installing contractor C. The property owner or designated representative
D. The municipal water utility provider
CORRECT ANSWER: C. The property owner or designated representative
Rationale: NFPA 25 and local codes place the legal responsibility for the ongoing inspection, testing, and
maintenance of fire protection systems squarely on the property owner or management.
Question 16: What color temperature rating corresponds to a standard commercial fire sprinkler rated
for an ordinary temperature classification of 135°F to 170°F?
A. Uncolored or Black B. Red C. Yellow D. Blue
CORRECT ANSWER: A. Uncolored or Black
Rationale: Standard temperature-rated sprinklers (135°F to 170°F) have glass bulbs that are
clear/colorless or frames that are uncolored, whereas higher temperature ratings use color-coded bulbs
(e.g., red, yellow, green, blue).
Question 17: When calculating hydraulic friction loss using the Hazen-Williams formula, what friction loss
coefficient (C-factor) is mandated for new black steel dry pipe or pre-action sprinkler piping?
A. 100 B. 120 C. 140 D. 150
CORRECT ANSWER: A. 100
Rationale: NFPA 13 specifies a C-factor of 100 for dry pipe and pre-action systems utilizing steel pipe due
to the higher likelihood of internal corrosion and scaling over time.
Question 18: What is the maximum spacing between branch line hangers for 1-inch steel pipe according
to standard NFPA 13 installation rules?
A. 8 feet B. 10 feet C. 12 feet D. 15 feet
CORRECT ANSWER: C. 12 feet
