CFI Fire Protection Systems Inspection 3 — Questions and Answers
Question 1: During standpipe system inspection, an inspector finds a Class I standpipe outlet with a 2½-inch hose valve on the 10th floor. The required residual pressure at this outlet is:
- 65 psi
- 100 psi (Correct answer)
- 150 psi
- 175 psi
Correct answer: 100 psi
NFPA 14 requires a minimum residual pressure of 100 psi at the hydraulically most remote 2½-inch hose connection in a Class I or Class III standpipe system.
Question 2: An inspector observes that a fire department connection (FDC) swivel fitting spins freely but cannot be tightened against the hose thread. What deficiency does this represent?
- The swivel is the wrong thread type
- The swivel gasket is missing or deteriorated (Correct answer)
- The FDC cap is the wrong size
- The check valve behind the FDC is stuck open
Correct answer: The swivel gasket is missing or deteriorated
A swivel that cannot seal against the hose indicates a missing or deteriorated swivel gasket, which would allow water to leak past the connection during firefighting operations.
Question 3: What does NFPA 72 require for the spacing of smoke detectors in a standard open-plan office with a smooth ceiling and 9-foot ceiling height?
- Maximum 900 sq ft coverage area per detector (Correct answer)
- Maximum 400 sq ft coverage area per detector
- Maximum 1,600 sq ft coverage area per detector
- Maximum 2,500 sq ft coverage area per detector
Correct answer: Maximum 900 sq ft coverage area per detector
NFPA 72 allows a maximum area coverage of 900 square feet per smoke detector on smooth ceilings, with a maximum spacing of 30 feet between detectors.
Question 4: An inspector checks a CO2 total flooding fire suppression system protecting a server room. The cylinder pressure reads lower than the specification on the agent quantity tag. Per NFPA 12, what is the maximum allowable loss of agent before the system must be recharged?
- 5% by weight
- 10% by weight (Correct answer)
- 15% by weight
- 20% by weight
Correct answer: 10% by weight
NFPA 12 requires recharging or replacement of CO2 cylinders when the agent loss exceeds 10% of the listed net weight.
Question 5: During inspection of a fire alarm control panel, the inspector finds a 'ground fault' trouble signal. What does this indicate?
- A smoke detector has been removed from its base
- An unintended electrical connection exists between a circuit conductor and ground (Correct answer)
- The primary power supply has failed
- A notification appliance circuit is open
Correct answer: An unintended electrical connection exists between a circuit conductor and ground
A ground fault trouble signal means one of the wiring conductors has developed an unintended low-resistance path to earth ground, which can interfere with system operation.
Question 6: An inspector is reviewing a foam-water deluge system protecting an aircraft hangar. Which type of foam concentrate is most commonly required for this application per NFPA 409?
- Class A foam
- Aqueous Film-Forming Foam (AFFF) (Correct answer)
- High-expansion foam
- Wet chemical agent
Correct answer: Aqueous Film-Forming Foam (AFFF)
NFPA 409 requires low-expansion foam such as AFFF for aircraft hangars because it rapidly spreads across fuel spills and seals fuel vapors to prevent ignition.
Question 7: A fire inspector tests the flow switch on a wet pipe sprinkler system by opening the inspector's test connection. The flow switch activates but the alarm bell does not sound. What is the most likely cause?
- The flow switch paddle is stuck
- The water motor alarm gong is dry or the alarm trim valve is closed (Correct answer)
- The inspector's test connection orifice is undersized
- The retard chamber is flooded
Correct answer: The water motor alarm gong is dry or the alarm trim valve is closed
If the flow switch signals correctly but the water motor alarm gong does not sound, the most likely cause is a closed alarm trim valve or a dry/obstructed water motor gong.
CFI Fire Protection Systems Inspection 3
During standpipe system inspection, an inspector finds a Class I standpipe outlet with a 2½-inch hose valve on the 10th floor.
The required residual pressure at this outlet is: