Smoke Control and HVAC Systems Flashcards

A fire alarm activates on the 10th floor of a high-rise with a smoke control system. Which action is typically automatic?

Answer: Starting stair pressurization fans

Stair pressurization fans usually start automatically on fire alarm to protect the exits.

How should the fire alarm system monitor a smoke control fan's operation?

Answer: By positive confirmation such as airflow or pressure proof

Smoke control components require positive confirmation of operation, such as airflow switches, not just a command signal.

While testing, the Certificate of Fitness holder finds a duct detector's remote test switch does not shut down the air handler. What should be done?

Answer: Report the impairment and have the interlock repaired

A failed HVAC shutdown interlock is a system impairment that must be reported and corrected.

Smoke dampers in a smoke control system should report their position to the control panel for what reason?

Answer: To confirm the damper actually reached its commanded open or closed state

Position feedback verifies the damper responded properly during smoke control operation.

An air handler is shut down for maintenance while its duct detector stays powered. What can happen?

Answer: The detector may not sample properly because there is no airflow

Duct detectors rely on airflow through the sampling tubes, so no airflow means unreliable sampling.

What is the purpose of a smoke purge (smoke removal) system after a fire?

Answer: To exhaust residual smoke and help the fire department clear the building

Smoke purge mode helps firefighters remove smoke from affected areas after the fire is controlled.

Before testing duct detectors that shut down HVAC in an occupied building, what should be done first?

Answer: Notify building management and the monitoring station, since fans and dampers will operate

Advance notice prevents false dispatches and surprises when HVAC equipment shuts down during the test.