The functional requirements are not the same:

Airtight door is in need of sealing effect, some airtight, watertight, weathertight different magnitude, there is a corresponding test to validate the function of the degree of perfection.

The fire door is in need of resisting flame failure effect, is to prevent the spread of fire facilities, which is part of the structure of fire, the fire resistance rating of the fire door is divided into A, B, C, A-60 which refers to the use of steel or other equivalent materials manufacturing and other refractory materials to strengthen, after 60 minutes of standard fire test, still can prevent smoke and flame through, and in accordance with the heat insulation and the corresponding temperature rise limit requirements. B, C class fire door also have the corresponding standard.

Sealing door is to increase the tightness of the door. Is used for temporary plugging of fire rescue, the local gas accumulation or overrun, equipment rapid plugging technology control of local high temperature fire point.

Explosion-proof door industrial building against accidental explosion outside the device, ensuring personnel safety and industrial equipments in buildings intact, without blast hazards; effectively prevent the continuation of explosion hazards