Fire Door Structure

The structure of a fire door refers to its components and design, primarily used to prevent the spread of fire and ensure safe evacuation during a fire. A fire door typically includes a door frame, door leaf, fire-resistant sealing strips, and hardware. The door frame and leaf are usually made of steel or wood, filled with fire-resistant and heat-insulating materials such as rock wool or aluminum silicate fiber to improve fire resistance. The fire-resistant sealing strip expands at high temperatures, further preventing the penetration of smoke and flames. Hardware includes fire-resistant locks, door closers, and hinges to ensure the door automatically closes and remains airtight during a fire. The structural design of fire doors must comply with national fire protection standards, such as GB 12955-2008 "Fire Doors," ensuring that their fire resistance meets specified requirements (e.g., a Class A fire door has a fire resistance rating of not less than 1.5 hours).