CAT Inspection & Quality Control 2 — Questions and Answers
Question 1: During an inspection of a smoke detector, the technician finds a layer of dust inside the sensing chamber. What is the correct action?
- Clean the chamber with compressed air and document the finding (Correct answer)
- Replace the detector immediately without documentation
- Leave it in place since dust does not affect ionization detectors
- Spray the chamber with a cleaning solvent
Correct answer: Clean the chamber with compressed air and document the finding
Dust in the sensing chamber can cause false alarms or reduced sensitivity, so cleaning and documenting the condition is required.
Question 2: What does NFPA 72 require regarding the spacing of heat detectors in a standard ceiling height room?
- Detectors must not exceed a listed spacing, typically 50 ft between units (Correct answer)
- Detectors may be placed anywhere as long as every 500 sq ft has one
- Heat detectors must always be spaced identically to smoke detectors
- Spacing is determined solely by the AHJ with no code guidance
Correct answer: Detectors must not exceed a listed spacing, typically 50 ft between units
NFPA 72 limits heat detector spacing based on the listed spacing provided by the manufacturer, commonly up to 50 ft.
Question 3: A pull station is found to be stuck in the activated position during inspection. What should the technician do first?
- Notify the building owner and place the panel in alarm bypass while repairing (Correct answer)
- Reset the panel remotely without inspecting the device
- Ignore it if the panel is not currently in alarm
- Cut power to the entire fire alarm system
Correct answer: Notify the building owner and place the panel in alarm bypass while repairing
The owner must be notified, and the impaired zone should be managed per NFPA 72 impairment procedures before repair.
Question 4: Which test verifies that an alarm signal initiated at a field device is received correctly at the central monitoring station?
- End-to-end functional test (Correct answer)
- Continuity test
- Hipot test
- Ground fault test
Correct answer: End-to-end functional test
An end-to-end functional test confirms the complete signal path from the initiating device through the panel to the monitoring station.
Question 5: When inspecting a control panel, the technician observes that a trouble LED has been masked with tape. What should be done?
- Remove the tape, investigate the underlying trouble condition, and document findings (Correct answer)
- Leave it since the building staff must have had a reason
- Replace the entire panel as it is non-compliant
- Reset the panel to clear the trouble
Correct answer: Remove the tape, investigate the underlying trouble condition, and document findings
Masking indicators is a code violation; the underlying trouble must be identified and corrected per NFPA 72.
Question 6: An inspection reveals that a duct smoke detector is installed in a supply air duct. What minimum airflow velocity is typically required for reliable duct detector operation?
- 100 to 4,000 ft/min as specified by the manufacturer (Correct answer)
- Any velocity since duct detectors work in still air
- At least 8,000 ft/min to draw samples effectively
- Below 50 ft/min to prevent damage to the sensor
Correct answer: 100 to 4,000 ft/min as specified by the manufacturer
Duct smoke detectors are listed for specific airflow velocity ranges, most commonly between 100 and 4,000 ft/min.
Question 7: After completing an annual inspection, which document should the technician leave on-site?
- A signed inspection record indicating findings, corrections, and the date (Correct answer)
- Only the work order from the central office
- A blank log sheet for the building owner to complete later
- Nothing; all records are kept exclusively at the service company
Correct answer: A signed inspection record indicating findings, corrections, and the date
NFPA 72 requires that a record of the inspection be maintained on the premises and be available to the AHJ.
CAT Inspection & Quality Control 2
During an inspection of a smoke detector, the technician finds a layer of dust inside the sensing chamber.
What is the correct action?