Smoke Control and HVAC Systems Flashcards
6 cards from real F80 practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Smoke Control and HVAC Systems flashcards as text
During a high-rise fire, what is the primary purpose of stairwell pressurization?
Answer: To prevent smoke from infiltrating evacuation stairwells
Stairwell pressurization creates a positive air pressure differential that prevents smoke from migrating into the stairwell, keeping evacuation routes tenable for building occupants and firefighters.
When a fire is confirmed in a high-rise building, what is the correct action regarding the HVAC system serving the fire floor?
Answer: Shut down HVAC serving the fire floor to prevent smoke spread through ductwork
HVAC systems can rapidly distribute smoke throughout a building via ductwork. Shutting down HVAC on the fire floor — and often the floors immediately above and below — is standard procedure to contain smoke spread.
A smoke damper's primary function in a fire is to:
Answer: Close automatically to prevent smoke migration through duct openings in fire barriers
Smoke dampers are installed in HVAC ducts where they penetrate smoke barriers. On activation (typically via smoke detector or fire alarm), they close to maintain the integrity of smoke compartments.
In a high-rise building, which area is typically maintained at the HIGHEST air pressure during a smoke control event?
Answer: The protected stairwell enclosure
Protected stairwells are pressurized to the highest level so that when doors are opened, air flows outward into corridors rather than allowing smoke to enter. This maintains tenable conditions in the primary evacuation route.
The Fire Safety Director receives an alarm indicating smoke detector activation in the return air plenum. What is the MOST likely concern?
Answer: Smoke is being drawn from a fire location and distributed through the HVAC return system
Return air plenums collect air from occupied spaces before recirculating it. A smoke alarm in the return plenum is a strong indicator that smoke from a fire is entering the HVAC system and risks being distributed building-wide.
Under NYC regulations, after the HVAC system is shut down during a fire alarm, who has authority to restart it?
Answer: The FDNY incident commander on scene
Once the FDNY is on scene and assumes command, authority over building systems — including HVAC restart — transfers to the FDNY incident commander. The Fire Safety Director must coordinate with and defer to FDNY command.