TEXAS DEPARTMENT OF INSURANCE
TFM10 NFPA 24 EXAM 2026–2027 –
SPRINKLER UNDERGROUND PRACTICE
QUESTIONS, ANSWERS & TECHNICAL
REVIEW
Core Domains
• Scope and Application of NFPA 24
• Working Plans and AHJ Approval
• Valve Requirements and Restrictions
• Post Indicator Valves and Fire Hydrants
• Piping Materials and Pressure Ratings
• Burial Depth and Installation Requirements
• Thrust Blocks and Joint Restraints
• Flushing and Hydrostatic Testing Procedures
Introduction
The Texas Department of Insurance TFM10 Sprinkler Underground Examination
assesses a candidate's mastery of NFPA 24, Standard for the Installation of Private
Fire Service Mains and Their Appurtenances, along with relevant Texas Insurance
Code provisions. This examination evaluates knowledge of underground fire
service main installation, valve placement restrictions, hydrant spacing, piping
materials, burial depths, thrust restraint, and system testing protocols. The exam
employs multiple-choice questions to test foundational theory and practical
application. Emphasis is placed on real-world code compliance, proper
,installation procedures, and the technical decision-making required for fire
sprinkler underground systems.
SECTION ONE: QUESTIONS 1–100
1. According to NFPA 24, which type of piping system is specifically intended
to carry water for both fire service mains and domestic service mains?
A. Dedicated Fire Service Mains
B. Combined Service Mains
C. Private Hydrant Mains
D. Standpipe Supply Mains
B. Combined Service Mains
RATIONALE: NFPA 24 defines a combined service main as a pipe system
intended to carry water for both fire service mains and domestic/industrial services,
whereas dedicated fire service mains are reserved solely for fire protection water
supply.
2. Before any private fire service main equipment is installed or remodeled, to
which entity must the working plans be submitted for approval?
A. The local plumbing inspector
B. The building owner's insurance underwriters
C. The Authority Having Jurisdiction (AHJ)
D. The general contracting company
C. The Authority Having Jurisdiction (AHJ)
RATIONALE: NFPA 24 requires that working plans be submitted for approval
to the Authority Having Jurisdiction (AHJ) before any equipment is installed or
remodeled.
,3. According to NFPA 24, which of the following systems is NOT covered by
the standard?
A. Automatic sprinkler systems supplied by private fire service mains
B. Private fire hydrants and monitor nozzles
C. Dry fire hydrants utilized for drafting operations
D. Water spray fixed systems supplied by private mains
C. Dry fire hydrants utilized for drafting operations
RATIONALE: NFPA 24 Section 1.1.3 explicitly states that the standard does
not apply to dry fire hydrants utilized for drafting or mains connected to dry fire
hydrants utilized for drafting.
4. NFPA 24 does NOT apply to underground mains serving sprinkler systems
designed per NFPA 13D when the nominal diameter is less than:
A. 2 inches (50 mm)
B. 3 inches (75 mm)
C. 4 inches (100 mm)
D. 6 inches (150 mm)
C. 4 inches (100 mm)
RATIONALE: NFPA 24 Section 1.1.4 states the standard does not apply to
underground mains serving sprinkler systems designed and installed in accordance
with NFPA 13D that are less than 4 inches (100 mm) in nominal diameter.
5. Which of the following valves shall NOT be installed in the piping from the
fire department connection to the fire service main?
A. Check valves
, B. Control valves
C. Relief valves
D. Drain valves
B. Control valves
RATIONALE: NFPA 24 prohibits control valves from being installed in the
piping from the fire department connection to the fire service main, ensuring
unrestricted water flow from the FDC.
6. Where are control valves permitted in relation to the fire department
connection?
A. Between the FDC and the fire service main
B. Downstream of the fire department connection
C. Only at the FDC
D. Nowhere in the system
B. Downstream of the fire department connection
RATIONALE: Control valves are permitted in the system downstream of the
fire department connection, allowing system isolation while maintaining
unrestricted FDC flow.
7. When more than one water supply exists, what shall be installed in each
connection?
A. Control valve
B. Check valve
C. Relief valve
D. Post indicator valve
TFM10 NFPA 24 EXAM 2026–2027 –
SPRINKLER UNDERGROUND PRACTICE
QUESTIONS, ANSWERS & TECHNICAL
REVIEW
Core Domains
• Scope and Application of NFPA 24
• Working Plans and AHJ Approval
• Valve Requirements and Restrictions
• Post Indicator Valves and Fire Hydrants
• Piping Materials and Pressure Ratings
• Burial Depth and Installation Requirements
• Thrust Blocks and Joint Restraints
• Flushing and Hydrostatic Testing Procedures
Introduction
The Texas Department of Insurance TFM10 Sprinkler Underground Examination
assesses a candidate's mastery of NFPA 24, Standard for the Installation of Private
Fire Service Mains and Their Appurtenances, along with relevant Texas Insurance
Code provisions. This examination evaluates knowledge of underground fire
service main installation, valve placement restrictions, hydrant spacing, piping
materials, burial depths, thrust restraint, and system testing protocols. The exam
employs multiple-choice questions to test foundational theory and practical
application. Emphasis is placed on real-world code compliance, proper
,installation procedures, and the technical decision-making required for fire
sprinkler underground systems.
SECTION ONE: QUESTIONS 1–100
1. According to NFPA 24, which type of piping system is specifically intended
to carry water for both fire service mains and domestic service mains?
A. Dedicated Fire Service Mains
B. Combined Service Mains
C. Private Hydrant Mains
D. Standpipe Supply Mains
B. Combined Service Mains
RATIONALE: NFPA 24 defines a combined service main as a pipe system
intended to carry water for both fire service mains and domestic/industrial services,
whereas dedicated fire service mains are reserved solely for fire protection water
supply.
2. Before any private fire service main equipment is installed or remodeled, to
which entity must the working plans be submitted for approval?
A. The local plumbing inspector
B. The building owner's insurance underwriters
C. The Authority Having Jurisdiction (AHJ)
D. The general contracting company
C. The Authority Having Jurisdiction (AHJ)
RATIONALE: NFPA 24 requires that working plans be submitted for approval
to the Authority Having Jurisdiction (AHJ) before any equipment is installed or
remodeled.
,3. According to NFPA 24, which of the following systems is NOT covered by
the standard?
A. Automatic sprinkler systems supplied by private fire service mains
B. Private fire hydrants and monitor nozzles
C. Dry fire hydrants utilized for drafting operations
D. Water spray fixed systems supplied by private mains
C. Dry fire hydrants utilized for drafting operations
RATIONALE: NFPA 24 Section 1.1.3 explicitly states that the standard does
not apply to dry fire hydrants utilized for drafting or mains connected to dry fire
hydrants utilized for drafting.
4. NFPA 24 does NOT apply to underground mains serving sprinkler systems
designed per NFPA 13D when the nominal diameter is less than:
A. 2 inches (50 mm)
B. 3 inches (75 mm)
C. 4 inches (100 mm)
D. 6 inches (150 mm)
C. 4 inches (100 mm)
RATIONALE: NFPA 24 Section 1.1.4 states the standard does not apply to
underground mains serving sprinkler systems designed and installed in accordance
with NFPA 13D that are less than 4 inches (100 mm) in nominal diameter.
5. Which of the following valves shall NOT be installed in the piping from the
fire department connection to the fire service main?
A. Check valves
, B. Control valves
C. Relief valves
D. Drain valves
B. Control valves
RATIONALE: NFPA 24 prohibits control valves from being installed in the
piping from the fire department connection to the fire service main, ensuring
unrestricted water flow from the FDC.
6. Where are control valves permitted in relation to the fire department
connection?
A. Between the FDC and the fire service main
B. Downstream of the fire department connection
C. Only at the FDC
D. Nowhere in the system
B. Downstream of the fire department connection
RATIONALE: Control valves are permitted in the system downstream of the
fire department connection, allowing system isolation while maintaining
unrestricted FDC flow.
7. When more than one water supply exists, what shall be installed in each
connection?
A. Control valve
B. Check valve
C. Relief valve
D. Post indicator valve
