In what scenario is a listed fire damper required in a multi-story duct installation?

A listed fire damper is required in a multi-story duct installation at each floor line if certain conditions are met, primarily to prevent the spread of fire and smoke between different floors in a building. Building codes and safety regulations often mandate the use of fire dampers at these points to maintain compartmentalization of fire zones.

If there is a duct that passes through multiple floors, the installation of fire dampers at each floor line ensures that in the event of a fire, smoke and flames are effectively contained, preventing them from traveling through the duct system and potentially affecting other areas of the building. This is especially crucial in high-rise buildings where fire safety is a prominent concern.

The specific conditions that might dictate the need for dampers could relate to the type of ductwork installed, the building occupancy, and the kind of fire resistance rated assemblies present in the structure. Such provisions support overall fire safety and compliance with local and national fire codes.