North Carolina Fire Sprinkler Contractor Exam
Questions & Answers with Rationales
1. According to NFPA 13, what is the minimum required clearance
between the deflector of a standard pendant sprinkler and the
ceiling?
A. 1 inch
B. 2 inches
C. 4 inches
D. 6 inches
Correct Answer: A. 1 inch
Explanation: NFPA 13 mandates a minimum clearance of 1 inch
between the sprinkler deflector and the ceiling to prevent
obstructions and ensure proper spray pattern development.
2. Which type of pipe material is strictly prohibited for use in fire
sprinkler systems unless specifically listed for the application?
A. Black steel
B. Galvanized steel
C. PVC
D. Copper
Correct Answer: C. PVC
Explanation: PVC is generally prohibited in fire sprinkler systems
due to its low melting point and inability to withstand heat, unless it
,is a specifically listed and approved material for a specialized
application (like some residential systems).
3. In a dry pipe sprinkler system, what is the primary purpose of the
dry pipe valve?
A. To regulate water pressure
B. To hold back water until air pressure drops
C. To act as a check valve for the fire department connection
D. To drain the system automatically
Correct Answer: B. To hold back water until air pressure drops
Explanation: The dry pipe valve is a differential valve that holds the
water supply back using compressed air. When a sprinkler opens,
the air escapes, pressure drops, and the valve trips, allowing water
to flow.
4. What is the maximum allowable distance between sprinklers on a
branch line for a light hazard occupancy with a standard spray
sprinkler?
A. 10 feet
B. 12 feet
C. 15 feet
D. 20 feet
Correct Answer: C. 15 feet
Explanation: NFPA 13 Table 10.2.3.2.1(a) limits the maximum spacing
for standard spray sprinklers in light hazard occupancies to 15 feet.
,5. Which of the following is NOT a component of a wet pipe sprinkler
system?
A. Alarm check valve
B. Dry pipe valve
C. Inspector's test connection
D. Main drain valve
Correct Answer: B. Dry pipe valve
Explanation: A dry pipe valve is specific to dry pipe systems. Wet
pipe systems use an alarm check valve or a riser check valve.
6. When performing a hydraulic calculation, what does the term "C-
factor" represent?
A. The flow coefficient of the sprinkler
B. The roughness coefficient of the pipe
C. The pressure loss due to elevation
D. The velocity of the water
Correct Answer: B. The roughness coefficient of the pipe
Explanation: The C-factor in the Hazen-Williams formula represents
the internal roughness of the pipe. Higher values indicate smoother
pipes with less friction loss.
7. What is the minimum required size for a fire department
connection (FDC) pipe supplying a sprinkler system?
A. 2 inches
B. 4 inches
C. 6 inches
, D. 8 inches
Correct Answer: B. 4 inches
Explanation: NFPA 13 requires the FDC pipe to be a minimum of 4
inches in diameter to allow adequate flow from fire department
pumpers.
8. In a deluge sprinkler system, what type of sprinklers are typically
used?
A. Fusible link sprinklers
B. Glass bulb sprinklers
C. Open sprinklers
D. Quick response sprinklers
Correct Answer: C. Open sprinklers
Explanation: Deluge systems use open sprinklers (no heat-sensitive
element) because the system is activated by a separate detection
system, allowing water to flow from all sprinklers simultaneously.
9. What is the maximum allowable height for a sprinkler above a
combustible concealed space?
A. 12 inches
B. 18 inches
C. 24 inches
D. 36 inches
Correct Answer: C. 24 inches
Explanation: NFPA 13 allows sprinklers to be omitted from
combustible concealed spaces if the space is filled with non-
Questions & Answers with Rationales
1. According to NFPA 13, what is the minimum required clearance
between the deflector of a standard pendant sprinkler and the
ceiling?
A. 1 inch
B. 2 inches
C. 4 inches
D. 6 inches
Correct Answer: A. 1 inch
Explanation: NFPA 13 mandates a minimum clearance of 1 inch
between the sprinkler deflector and the ceiling to prevent
obstructions and ensure proper spray pattern development.
2. Which type of pipe material is strictly prohibited for use in fire
sprinkler systems unless specifically listed for the application?
A. Black steel
B. Galvanized steel
C. PVC
D. Copper
Correct Answer: C. PVC
Explanation: PVC is generally prohibited in fire sprinkler systems
due to its low melting point and inability to withstand heat, unless it
,is a specifically listed and approved material for a specialized
application (like some residential systems).
3. In a dry pipe sprinkler system, what is the primary purpose of the
dry pipe valve?
A. To regulate water pressure
B. To hold back water until air pressure drops
C. To act as a check valve for the fire department connection
D. To drain the system automatically
Correct Answer: B. To hold back water until air pressure drops
Explanation: The dry pipe valve is a differential valve that holds the
water supply back using compressed air. When a sprinkler opens,
the air escapes, pressure drops, and the valve trips, allowing water
to flow.
4. What is the maximum allowable distance between sprinklers on a
branch line for a light hazard occupancy with a standard spray
sprinkler?
A. 10 feet
B. 12 feet
C. 15 feet
D. 20 feet
Correct Answer: C. 15 feet
Explanation: NFPA 13 Table 10.2.3.2.1(a) limits the maximum spacing
for standard spray sprinklers in light hazard occupancies to 15 feet.
,5. Which of the following is NOT a component of a wet pipe sprinkler
system?
A. Alarm check valve
B. Dry pipe valve
C. Inspector's test connection
D. Main drain valve
Correct Answer: B. Dry pipe valve
Explanation: A dry pipe valve is specific to dry pipe systems. Wet
pipe systems use an alarm check valve or a riser check valve.
6. When performing a hydraulic calculation, what does the term "C-
factor" represent?
A. The flow coefficient of the sprinkler
B. The roughness coefficient of the pipe
C. The pressure loss due to elevation
D. The velocity of the water
Correct Answer: B. The roughness coefficient of the pipe
Explanation: The C-factor in the Hazen-Williams formula represents
the internal roughness of the pipe. Higher values indicate smoother
pipes with less friction loss.
7. What is the minimum required size for a fire department
connection (FDC) pipe supplying a sprinkler system?
A. 2 inches
B. 4 inches
C. 6 inches
, D. 8 inches
Correct Answer: B. 4 inches
Explanation: NFPA 13 requires the FDC pipe to be a minimum of 4
inches in diameter to allow adequate flow from fire department
pumpers.
8. In a deluge sprinkler system, what type of sprinklers are typically
used?
A. Fusible link sprinklers
B. Glass bulb sprinklers
C. Open sprinklers
D. Quick response sprinklers
Correct Answer: C. Open sprinklers
Explanation: Deluge systems use open sprinklers (no heat-sensitive
element) because the system is activated by a separate detection
system, allowing water to flow from all sprinklers simultaneously.
9. What is the maximum allowable height for a sprinkler above a
combustible concealed space?
A. 12 inches
B. 18 inches
C. 24 inches
D. 36 inches
Correct Answer: C. 24 inches
Explanation: NFPA 13 allows sprinklers to be omitted from
combustible concealed spaces if the space is filled with non-
