In daily life, elevators are increasingly indispensable, but we still do not have enough understanding of their temperament. The Xi'an Municipal Bureau of Quality Supervision and the Sanqin Urban Daily have jointly launched the second series of reports on "Xi'an Quality First" to see what misconceptions people have about elevator safety? A professional gave everyone a reassurance: "Let's put it this way, even if all the steel cables are cut during operation, there won't be a sudden descent of the elevator, because it's like the handbrake and foot brake of a car, and the insurance system of the elevator also has' brain brake, leg brake 'and other powerful brakes. Therefore, the tragedy of elevator accidents is not caused by elevator quality defects, and many people have misconceptions about it."
Mistake 1: "Escape by easily scraping the door or climbing up the ceiling." Elevators have two doors, one is the hall door and the other is the car door. The hall door is equipped with an automatic locking device. Once locked, unless the elevator car is in place and the hall door and car door overlap, the mechanical lock hook cannot be opened. "The relevant person in charge of Xi'an Special Equipment Inspection and Testing Institute explained that in case of emergency, only professional certified personnel can open the hall door by using a dedicated triangular key to open the lock hook. "The scene of pushing the ceiling upwards and climbing out of the elevator, which is often portrayed in movies, is quite exaggerated. Although there is an emergency exit on the top of the elevator, it needs to be illuminated by the ceiling and a dedicated key to open it." He explained that the top of the elevator car is where maintenance personnel work, surrounded only by work railings. If unfamiliar passengers accidentally board, they not only cannot escape from the shaft, but also are prone to danger and injury.
Mistake 2: If an elevator malfunctions, it will suddenly fall down. "Vertical elevators have complete protective devices, are under normal maintenance, and will not suddenly fall." He explained that what passengers refer to as "slides" or "slides" are actually mostly illusions. The elevator has at least three security devices. Firstly, elevators all have brakes. In the event of a malfunction or power outage, the brakes will lock the traction motor and stop rotating, ensuring elevator safety. Secondly, upper and lower limit inspection switches and forced deceleration switches are installed in the shaft where the elevator operates. If the elevator reaches the upper and lower limits, the elevator system will enter a forced deceleration and predetermined state. Thirdly, when the speed limiter detects elevator overspeed, it will interlock with the safety caliper brake to lock the elevator car onto the guide rail. It's like two big pliers, once the elevator goes down at high speed, it will hold tightly to prevent falling. In case the elevator quickly descends to the bottom, there is still a buffer at the bottom of the elevator to slow down the impact force when landing. He introduced that during the operation of the elevator, if a small malfunction occurs that causes problems with the elevator floor detection signal, the elevator will enter a protection restart state, automatically stop the corresponding button command, and reset the floor data by returning to the bottom or top floor. Due to the inability of passengers to control the elevator during this process, and the elevator constantly running, it led to people mistakenly thinking it was a "slide" or "slide" of the elevator.
Mistake 3: Why did the display screen on the third floor change from the 8th floor to the 6th floor? "When the elevator malfunctioned, it stumbled and suddenly the floor display screen changed from the 8th floor to the 6th floor." Many passengers were puzzled as the elevator "fell" from the 6th floor to the 4th floor. "? This is too scary. In fact, when the elevator is running, the displayed numbers do not correspond very accurately to the floor. He explained that during elevator operation, for the comfort of passengers, it starts, accelerates, decelerates, and stops according to a specific operating curve. Especially for high-speed elevators, the running distance per second exceeds 3 meters, which is greater than one floor height. However, in order to enhance the visual experience of passengers riding the elevator, the displayed floor numbers are stacked at a constant speed, so that passengers do not think that the elevator is suddenly fast or slow. When a malfunction occurs, if the elevator happens to be in the process of starting acceleration or deceleration, there is a certain error between the actual position and the displayed floor number. After the elevator self-protection stops, the floor display will automatically switch to the actual position. This actually leads to passengers mistakenly thinking that the elevator has suddenly dropped several floors. In fact, the elevator stops within the normal braking distance and does not slip.
Mistake 4: Elevator malfunction is an accident. Some citizens may hear abnormal noises while riding the elevator, or the elevator car may shake slightly during operation. In such situations, there is no need to panic. It is reported that various situations may occur during the operation of elevators, such as abnormal noises, shaking, emergency stops, and even trapping people. These are just malfunctions that occur during the operation of the elevator, not elevator accidents. Elevator accidents have a strict and clear definition. According to the relevant laws and regulations on special equipment, elevator accidents can only be classified as elevator accidents if a person is stranded in the elevator car for more than 2 hours or if the elevator causes serious injury, death, or significant property damage.
Mistake 5: Elevator shutdown=elevator accident. During elevator operation, when encountering a sudden power outage and being trapped, most people's reaction is "encountering another elevator accident". But professional analysis suggests that closing the elevator is actually a protective measure for passengers. "When the safety detection system detects abnormalities or malfunctions in the elevator during operation, it automatically takes a normal response to protect passengers, which is why people are shut down." Professionals say that power outage shutdown is essentially due to a sudden power outage, causing the elevator to stop operating without electricity and stop the elevator car in the shaft. The passengers who are locked in the elevator are safe at this time, and maintenance personnel only need to manually turn the car to safely release the passengers. In case of emergency situations such as elevator trapping, first press the emergency alarm button and contact the duty personnel of the property management company; Secondly, you can call the rescue hotline of the maintenance unit; If contact is unsuccessful, immediately call the emergency hotline for elevator 96333 (in areas where 96333 is not available, call the local emergency hotline for elevators) and seek assistance from professionals. Remember, under no circumstances should you engage in dangerous behavior such as climbing the top of the car without authorization or forcefully opening the car door.
Mistake 6： The six doors cannot be closed due to the elevator being broken. Residents have reported that the elevator in their residential unit often freezes or repeatedly opens and closes without closing the door. In fact, this situation is caused by foreign objects embedded in the sliding track of the elevator floor door, or by foreign objects blocking the passage of light in the light curtain area of the elevator door. The elevator door has safety contacts, and as soon as the door is opened, the elevator will stop running. If the elevator car door or hall door is not closed for a certain period of time, the door interlock protection device will be activated, and the elevator will automatically stop. In addition, excessive behavior such as forceful door scraping by someone outside the elevator may also cause the door interlock to disconnect and the elevator to stop running.
Mistake 7: Trapped elevators can cause suffocation. Many passengers are worried that if the elevator malfunctions and gets trapped, in a narrow elevator, failure to receive timely rescue can lead to suffocation. In fact, there are strict regulations in elevator standards at present, and only when the ventilation meets the required effect can it be put on the market. In addition, there are gaps at the connection positions of some ventilation devices in the elevator car, such as the connection between the car wall and the car roof, which are generally sufficient for people's breathing needs.
