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Author of factors that trouble the use of fire elevators and countermeasures: Wu Weiguo, Jilin Yanbian City Fire Detachment, Fire Protection Code for High-rise Buildings in my country: Public buildings, industrial buildings with a height of more than 32 meters and residential buildings with more than 12 floors should be equipped with fire elevators. So in the event of a fire, it is difficult for the current fire elevator to play its due role, and its safety and reliability are not very high. There are many factors that trouble the reliable use of fire elevators, mainly including the following aspects:: 1. Factors affecting the reliable use of fire elevators: (1) Fire elevators are susceptible to fire damage. 1. Fire elevator machine rooms are generally located on the top of buildings. According to regulatory requirements and from the perspective of machine room safety, independent fire protection zones are required. But in fact, due to the gaps caused by cables and air ducts passing through the wall, fire doors cannot be kept normally closed, etc. In the event of a fire, the heart equipment of the elevator is easily affected by high temperatures, leading to paralysis. 2. The shaft of the fire elevator is not set up independently as required by the regulations. However, some fire elevators and passenger elevators share the shaft without effective fire separation between them. Since the passenger elevator does not have a fire front room, it is susceptible to fire damage, which will affect the "neighbors" and cause the fire elevator to not be used normally. 3. The cables that supply the power supply to the fire elevator are usually discharged from the strong current shaft of the building to the top, and then discharged into the elevator machine room through a bridge. Although fireproof cables are used and have certain fire resistance, it is difficult to permanently maintain normal power supply in the event of a building fire. (2) Fire elevators are susceptible to smoke damage. 1. There is no effective fire separation in the front room of the fire elevator. The main reason is that there are holes in the wall of the front room and the fire door cannot be kept closed. 2. The mechanical pressurized air supply system in the front room of the fire elevator failed to function effectively. Generally, the front room of fire elevators does not have natural ventilation and lighting, and a mechanical pressurized air supply system is required to prevent smoke from entering. However, due to the failure of the front room fire door to close in the event of a fire, the failure of the mechanical positive pressure air supply, the improper setting of the mechanical pressurized air supply port to generate eddy currents, the piston effect of the elevator car, etc., harmful smoke will invade the fire elevator front room. 3. There is no effective fire separation between the fire elevator machine room and other elevator machine rooms as required by the regulations. Since the fire and smoke prevention requirements of non-fire elevators are different, due to the piston effect of the car, smoke can easily be sucked into the elevator machine room, and then sucked into the fire elevator shaft from the machine room and into the fire elevator car, endangering personal safety. (3) The technology of fire elevators is currently difficult to fully ensure their safe use. 1. The fire elevator itself is not waterproof, which is a worldwide problem. The control panels of fire elevators are not waterproof, and all building fires require a large amount of water to put out the fire. Even if water retaining facilities are provided according to current regulations, it is difficult for fire elevators to be used during fire fighting. 2. The control methods of fire elevators have not yet been unified. because * * There is no unified standard, so some fire elevators have special fire start buttons for fire protection, while others require a special matching key to achieve the same function. ； After some special buttons are activated, the car automatically descends to the first floor and the door opens. The internal buttons can be used by fire fighters, and the external floor buttons automatically become invalid. However, after some special buttons for fire elevators are activated, the fire elevator can still be used normally. The car can be used as usual without forced descent to the first floor or external floors, which cannot meet the requirements for the use of fire elevators. 3. The fire elevator itself has no reliable safety performance. Most of the fire elevators currently in use do not have anti-fall functions, and there are no emergency escape hatches in the car. There are many reasons for the above problems, including standard issues, technical issues, and design, construction, and management issues. Any omission or disconnection in any link will affect the reliable use of the fire elevator. 2. Several methods to improve the reliability of fire elevators are based on the principle of setting them up for use and using them for reliability. They should be improved from the following aspects. (1) Revise and improve the technical standards for fire elevators to improve the reliability of fire elevators themselves. 1. Clarify the technical standards for fire elevators, unify the control procedures, clarify the priority of special fire protection functions, and uniformly set up a special fire protection start button on the first floor as a fire protection function conversion switch. 2. For the waterproofing of fire elevators, corresponding technical requirements can be put forward based on a thorough investigation, so as to gradually develop towards waterproof elevators. 3. Add a layer-joining function when the fire elevator is powered off (the elevator car automatically opens the door and stops at the nearest floor), installs an anti-fall function through mechanical means, and adds an emergency escape hatch on the top of the elevator car to ensure that people can safely escape from the car when the fire elevator fails. (2) Adjust the relevant requirements of the current building design fire protection regulations to ensure a safe operating environment for fire elevators. 1. Improve the smoke-proof design of fire elevators. Current regulations emphasize positive pressure air supply in the front room of fire elevators to prevent smoke from entering by increasing the air pressure in the front room. Due to the location of the positive pressure air supply vent and the difficulty in keeping the fire door normally closed, the actual smoke prevention effect of this method may not be ideal. The effect of air supply and pressurization through the fire elevator shaft may be more ideal, and its effect of preventing smoke from entering the front room and car should be more obvious. 2. Strengthen the blocking and drainage capabilities of the fire elevator front room. Although the specification has requirements for this, it has not been successfully applied in many projects. Since fire fighting requires a large amount of water, it is easy for water to flow into the elevator and affect its use. Therefore, it should be emphasized that in the front room of the fire elevator, there is a certain downward slope from the elevator entrance to the door. At the same time, a drainage channel should be added at the elevator entrance to drain the water to the water collection well through a special drainage pipe in the elevator shaft to effectively prevent running water from entering the fire elevator. 3. Improve the laying method of fire elevator cables. Cables laid in the current way are susceptible to fire threats. The fire elevator cables can be directly connected from the shaft to the elevator machine room from the lower distribution room to reduce the threat of fire to the cables. 4. Appropriately reduce the conditions for building fire elevators. In order for fire elevators to be truly effective, the installation requirements are quite high, and cities with relatively concentrated high-rise buildings are equipped with fire aerial vehicles of about 45 meters. In order to reduce construction costs, it is recommended that the standard for fire elevators be adjusted from 32 meters to 45 meters, or even higher. (3) Increase the construction quality and operation management of fire elevators. At work, we often find that fire elevators cannot be used normally due to inadequate construction and management. Therefore, on the one hand, we must have practical and effective standards, and on the other hand, we must also increase the construction quality and operation management of fire elevators. (4) Strengthen the training of firefighters on the use of fire elevators and their ability to escape in emergencies. Since the structural forms and fire function operation methods of various fire elevators are very different, it is very necessary to train firefighters in this area and make up for this lesson to ensure that in emergencies, firefighters can escape smoothly and avoid life safety threats.