A fire damper for a ventilating fan includes a shutter and a frame provided with a flange. A preformed opening is provided on the frame. The frame is further provided with a movable component for opening or closing the preformed opening. This has the advantage of being able to share parts with others.

A fire damper for a ventilating fan includes a shutter and a frame provided with a flange. An opening is provided on the frame. The frame is further provided with a movable component for covering or uncovering the opening.

A system for blocking transmission of smoke through a passageway, and related systems and methods, are disclosed herein. In some embodiments, the system includes a housing, a deployable barrier positioned to move between a retracted position and a deployed position, a motor coupled to the deployable barrier, and a deploying circuit coupled to the motor. The weight of the deployable barrier can drive the motor in reverse during deployment to generate a current in an inductive component of the motor. The deploying circuit can have a first setting that applies the current to an output of the deploying circuit to dissipate the current and a second setting that applies the current as a load upstream from the inductive component to resist driving the motor in reverse. The system can also include a controller coupled to the deploying circuit to switch between the first setting and the second setting.