A round fire damper is a device that is used to help prevent the spread of fire and smoke through air ducts and other ventilation systems. It is a round metal disc with a number of blades that open and close to regulate the flow of air. When the blades are closed, the damper restricts the flow of air, which can help to contain the fire and smoke. When the blades are open, the damper allows air to flow freely, allowing the fire to spread. Fire dampers are typically installed in ceilings, walls, and floors to help contain the spread of fire and smoke. They are also used in air ducts to help prevent the spread of fire and smoke from one area to another. Fire dampers are an important part of any fire safety system and should be inspected regularly to ensure they are functioning properly.