Do you really understand the fire doors that often appear around us?
The fire door is a very important and common fire protection facility in our lives. We are no strangers to fire doors, but many people do not understand it. Fire doors usually refer to doors located in some enclosed places such as stair walkways, elevator rooms, cable shafts, flue gas ducts, and so on. The role of the fire door is to meet the fire stability and heat insulation within a certain period of time, can prevent the spread and spread of the fire, and ensure the evacuation of personnel. It is an indispensable equipment in the fire fighting work.
According to the different open or closed state of fire doors, they are often divided into normally closed fire doors and normally open fire doors. Do you know the difference between normally closed fire doors and normally open fire doors?
The normally closed fire door is normally closed and needs to be pushed open when there are people walking around. The open state of normally closed fire doors has certain shortcomings. Because the place where the fire door is installed is usually the passage where people often walk, it causes certain contradictions. Especially in large shopping malls, there is a large flow of people. If a normally closed fire door is installed in the evacuation stairwell, the fire door will soon be damaged and fall off due to frequent opening and closing, which will not play the role of fire prevention and cause fire hazards. Normally open fire doors are open at ordinary times, and automatically close in case of fire. Because it is kept open at ordinary times, it is convenient for people to pass through, and it is convenient for ventilation and lighting. It can be closed by itself in the event of a fire, which plays a role in preventing smoke and fire, thus solving the inconvenience caused by the closing of the fire door and the inconvenience caused by the fire door. Man-made damage caused by frequent opening and closing. Therefore, in the evacuation stairwells of some large shopping malls, a normally open fire door should be installed, which is usually open. When a fire occurs, various sensors are used to control the door closer to close the door.
Under what circumstances should a normally open or normally closed fire door be used?
Normal open fire doors should be used for fire doors installed in buildings where people often pass through. In other words, fire doors in public parts of the building (traffic core) including smoke-proof staircases, front rooms of fire elevators, and shared front rooms should be normally open fire doors, and fire doors in the evacuation aisles of the hall should also be normally open. fire-proof door. Except for the positions where normally open fire doors are allowed, the fire doors in other positions shall be normally closed fire doors. In other words, in the design, except for the normally open fire doors indicated in the drawings, all other fire doors should be normally closed fire doors. This requires that when the designer chooses a fire-resistant door, if the code requires a normally-open fire-resistant door, it must be noted in the door and window table, and the inspector can conduct an inspection based on this.