Can I use wall penetrations as restraint points for ductwork?
Yes, to some degree. It is best determined by a qualified seismic design engineer. Common practice is to use wall penetrations as lateral restraints if the wall is considered strong enough and the design forces small enough. Fire dampers, since they are made to be structurally integral with the wall partition, are commonly used as restraint points for lateral loads and longitudinal loads in one direction (into the wall). Since the duct connection to these devices is designed to allow the duct to fall away, they cannot be used as longitudinal restraint points for forces moving away from the wall.