What must be listed and installed in accordance with their listing for ducts and air transfer openings permitted in firewall?

Fire dampers are critical components in maintaining the integrity of firewalls. They are designed to prevent the spread of fire and smoke through ducts and air transfer openings that penetrate fire-resistance-rated walls. When a fire occurs, fire dampers automatically close when they detect heat, effectively sealing off the ductwork from the surrounding environment.

The listing of fire dampers refers to their compliance with specific standards and testing protocols, ensuring they function as intended under fire conditions. Proper installation according to these listings is essential to ensure that the dampers operate effectively and provide the necessary protection against fire spread.

While smoke detectors, ventilation fans, and circuit breakers are important in various safety and operational contexts, they do not directly pertain to the physical barriers established by firewalls. Smoke detectors are used for early fire detection, ventilation fans manage air movement, and circuit breakers protect electrical circuits, but none of these items provide the necessary fire stopping required for maintaining the integrity of a firewall like fire dampers do. Thus, their listing and installation requirements are specifically focused on ensuring compliance with fire safety codes related to ductwork within fire-rated assemblies.