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Fire door usually refers to the door on the firewall and fire partition wall set in the stair walkway, escape walkway, elevator room, cable shaft, smoke exhaust duct, closed and scattered stairs, which are used to distinguish the fire compartment and control the construction area of the compartment. The effect of fire door is that it can meet the fire resistance stability and heat insulation at a certain time, prevent the spread and dispersion of fire, and ensure the dispersion of personnel. It is an equipment in fire fighting work. Fire doors are generally divided into normally closed fire doors and normally open fire doors, so what is the difference between the two?

Normally open fire door

Keep it open at ordinary times, so that personnel can pass easily, ventilation and lighting are convenient, and it can be automatically closed in case of fire, so as to achieve the effect of smoke and fire prevention. Thus, it solves the problem that the fire door is usually closed, which leads to inconvenient passage of personnel, and the fire door is damaged due to frequent opening and closing, which together ensures the fire protection.

Normally open fire doors are generally installed in places with many people, such as campuses, large shopping malls, hospitals and so on. These local people often go in and out of the staircase, so it is inconvenient to install normally closed fire doors. If the fire door is often opened, it will lead to the damage of the normally closed fire door, which will not have the fire prevention effect and form a fire hazard. Therefore, normally open fire doors are generally installed in these places.

When a fire occurs, the fire door monitor will announce the alarm signal and let the electric door closer close the fire door together. Normally open fire doors are closed under the effect of electric door closers. The effect of the electric door closer is to automatically close the normally open fire door after receiving the signal. Together, the signal shall be reflected to the fire door monitor to inform the fire door monitor that the door has been closed. The fire door monitor will not alarm after receiving the response signal. In this way, the normally open fire door will be closed under the effect of the fire door monitoring system when the fire occurs, so as to achieve the effect of smoke and fire separation.

Normally closed fire door

In order to prevent the smoke or fire from passing through the door opening into the scattered passages and staircases of personnel in case of fire, and ensure the relative dispersion of the scattered passages and the dispersion of personnel, the fire doors in these parts shall be normally closed, and can be closed by themselves after the personnel are dispersed in case of fire.

Normally closed fire doors are generally installed in places with few people. Under normal circumstances and in case of fire, it should be in a closed state. When someone moves around, it needs to be pushed away, which has the effect of separating smoke and fire and preventing the spread of fire. Some people say that it is already in a closed state. Does it need to install a fire door monitoring system? The answer is still need to install. As normally closed fire doors cannot be guaranteed to be closed all the time.

At present, there are many fire accidents, many cases are due to the fact that the normally closed fire door is artificially opened, such as using fire extinguishers or bicycles to make it open. Once the normally closed fire door is open for a long time, when a fire occurs, the fire is easy to spread to the stairwell and other fire passages, which does not have the effect of fire prevention.

Normally closed fire doors shall be set in the following places and parts: fire doors of high-rise residential buildings, pipe wells attached to buildings, fire control rooms, fire pump rooms and other equipment rooms. The normal flow of people and logistics in these buildings and parts are relatively fixed, which can ensure the "closed" function of normally closed fire doors in practical use.

Therefore, normally open fire doors and normally closed fire doors need to be selected according to different setting places. Both normally open fire doors and normally closed fire doors can effectively prevent the spread and dispersion of fire and ensure the dispersion of personnel. They are equipment in fire protection work.

Article source: fireproof glass door http://www.m.hzjunyuekj.cn/