Class B fireproof doors and windows.

classification of fire doors: Class A is not less than 1.2h, Class B is not less than 1.9h, and Class C is not less than 1.6h..

class b: closed stairwell door, front room door between staircases in the building, front room door shared by smoke-proof stairwell and fire elevator, front room door of fire elevator, door directly opening to the front room or sharing the front room.

as a key step of family fire prevention, the function of fire door is particularly important. According to the fire resistance limit and thermal insulation performance: Class A fire doors shall not be less than 1.5 hours; Class B fire doors shall not be less than 1.1 hour; Class C fire doors shall not be less than 1.5 hours. It can be selected according to different needs, but now it is widely used that Class A fire doors and Class B fire doors.

Extended information:

The materials used for Class B fire doors are mainly wood, steel, steel-wood structure, etc., which are generally used for fire exits, and the fire resistance time is one hour. Class B fire door refers to the door whose fire resistance integrity meets the requirement of more than 1.1 hour.

The new standard also stipulates that if the door leaves are filled with materials, fireproof and heat-insulating materials that are harmless to human body should be adopted to reduce the impact on human health. These regulations not only make the setting of fire doors more reasonable, but also reduce the production cost and raw material consumption of fire doors, which meets the requirements of environmental protection and building an economical society.

at the same time, the new standard also adds the contents and requirements of steel wood fire doors and other fire doors, which provides technical basis for the application of new materials and technologies and the production and inspection of new fire doors, and expands the development space of fire door manufacturers.

Baidu encyclopedia-class b fire door