Fire doors are doors designed to withstand smoke and high temperatures from fires, commonly used in public places such as apartment buildings, hotels, and schools, as well as in corridors and stairwells of residential buildings. The primary fire-resistant principles of fire doors include the following aspects:

Material Special: Fire-resistant doors are typically made of steel as the main material. This material boasts strong fire resistance, capable of withstanding flames and high temperatures for a certain period, thereby acting as a barrier and preventing the spread of fires.

Sealant Performance: The fire door's door leaf and frame are filled with a special thermal insulation material, which boasts an extremely low thermal conductivity and excellent sealing properties. This ensures that during a fire, there will be no air leakage through the door gap, preventing the spread of flames and smoke into the room.

3. Robust Door Structure: Fire doors typically feature multi-layer steel plates for reinforcement, ensuring a highly stable structure that effectively prevents warping or collapse of the door leaf during a fire.

4. Comprehensive Facilities: Fire-resistant doors are often equipped with intelligent control systems and emergency release devices, allowing for rapid and effective responses in the event of a fire. The intelligent control system can detect fires early and initiate warnings as well as gas and foam extinguishing, while the emergency release devices facilitate quick evacuation of personnel, preventing entrapment.

Overall, fire doors serve as a fire protection measure, primarily through the fire-resistant properties of steel materials, excellent sealing, structural stability, and additional emergency control systems, creating a more robust environment to safeguard the safety of the people.

It's important to note that a quality fire door must undergo rigorous testing, certification, and obtain the corresponding departmental certificates to ensure reliability and performance guarantees. This is indicated by a fire rating symbol, DN, followed by a number, with a higher number signifying a longer fire resistance time. Therefore, when purchasing fire doors, we must be diligent in distinguishing and choosing reliable fire doors that meet national standards.