The Counting of Casualty Accidents in Elevators and Measures to Prevent Accidents in Elevators

In the face of frequent injuries and deaths caused by elevators, elevator operators are required to effectively implement the requirements of safety technical specifications such as the “Regulations for the Use of Elevators and Maintenance”, strengthen daily inspections of elevator operations, and strengthen the implementation of management systems such as elevator keys. More importantly, it is necessary to study how to prevent or eliminate the recurrence of elevator casualties through technical innovations or technological improvements and upgrades.

First, the elevator accident inventory

The use of elevators has been used for more than 100 years now . The scale of use of elevators is increasing and the technology is constantly improving. The safety factor is constantly increasing. The safety gear has been used as a necessary and most important facility installed in the elevator system to prevent the occurrence of a car falling accident due to various reasons and basically to protect the safety of passengers. The problem now is mainly that accidents that have caused casualties due to various reasons, such as falling on the hoistway after the elevator has opened the hall door, and cuts and injuries caused by leaving the car open have always existed. This is not uncommon. The following two years of elevator accident inventory:

In 2012 , there were 36 elevator accidents in China , 28 deaths and 15 injuries . among them:

1), 2012 April 13 evening around 6:50, Huiyang freshwater Health and Long Building, 6th floor residential elevator rose to sudden failure, the administrator unlock, owner Ms. Fang accidentally fell into the shaft when the elevator down from the , fell to the ground floor and died.

2), 2012 September 13 afternoon, Wuhan, Hubei a construction site accident occurred Passenger elevator falling from one hundred meters altitude, killing 19 people. According to media reports, the use registration plate for the accident lift has exceeded the limit period. In addition, the registration card indicated that the authorized number of elevators was 12 people, and there were 19 workers in the lift on the scene of the accident , which was obviously overloaded.

3), 2012 October 27, Hefei, when two young men between the elevator ride to the 10th floor and line the 11th floor, the elevator does not move suddenly failed. After the district security informed the lift maintenance company, the organizers carried out simple rescue. When the first person was rescued, the other person jumped off the elevator and fell into the elevator shaft and died.

4) in Sep. 6, 2012 on the 11th night, Wenzhou, Ms. Yu, 37, holding a 18-month-old son down the stairs, with her mother in the back waiting for the elevator together. Soon the elevator door opened, and when she took her son into the elevator, the elevator was empty, but the door opened and the elevator still remained on the seventh floor. The mother and son directly fell from the sixth floor to the elevator shaft in the first floor. His mother died and her son was slightly injured.

The elevator casualties review in the first half of 2013 :

1), March 16, 2013 evening, the Guangzhou Institute of Physical Education Graduate small sinus ready to send his girlfriend back to the dorm, during which he was leaning against the elevator door on the 6th floor of the dormitory, only two months of this disabling the elevator door suddenly opened After the small sinus planted the elevator shaft and fell directly to the negative 2 levels, he died due to injury.

2), in May 2013, killing frequent elevator, three days 4 from the elevator "swallow" and the accident, people are amazed, take the elevator some apprehension:

On May 14 , an escalator at the Wal-Mart supermarket in Yichang, Hubei Province broke down; a woman died; on the same day, a woman in Xi’an, Shaanxi province escaped from the 15th floor by elevator ;

May 15, Shenzhen, Guangdong, a female nurse was killed in the elevator chuck;

On May 16 , in Yuxi, Yunnan, a 61 -year-old man fell to the hospital elevator and died.

To this end, the State Administration of Quality Supervision, Inspection and Quarantine Bureau issued an emergency notice to require elevator users to effectively implement the “safety regulations and rules for the use of elevators” and other safety technical specifications, strengthen daily inspections of elevator operations, and strengthen elevator key management systems. The implementation.

Further analysis of the actual situation is even more serious because elevator accidents do not all occur at the first floor or the leveling floor. If an improper method or negligence occurs when opening the hall door, it is very easy to fall accidentally when the elevator stops in the middle of the two floors. At that time, trapped persons were also prone to falling accidents when escaping, and once a high-altitude crash occurred, the consequences could be imagined, and non-death had to be seriously injured. Most of the elevator base stations are located on the first floor, and the related operations are mostly on this floor. Sometimes people fall into elevator pits that do not have a basement, and most of them cause falls. Severe people are disabled and fall into elevator pits with basements. , it may come to life.

Since the use of elevators on a large scale, this type of casualty accident has existed all over the world, and it has become one of the most important reasons for the use of elevator-related fatal accidents. At present, there is no good solution. In China, according to rough statistics, 95% of elevator-related casualty accidents fall into the category of wells, which is generally similar to foreign countries.

Analyzing elevator casualties in the past, most of the operators opened the hall door and observed that the elevator was on the floor, and some were caused by negligence and fell into the hoistway. The problem is that the physiological characteristics of human beings cannot completely eliminate and overcome various kinds of carelessness, negligence, and mistakes. At this time, mistakes have led to the occurrence of security accidents. In addition, falling or shearing accidents caused by walking stairs or escalators when the hall door is open are also occurring. In such elevator accidents, the limbs of the parties were caught in the elevator car and the ground or hall door and caused casualties. On May 15th , a female nurse in Shenzhen, Guangdong was killed by an elevator collet. It was a frightening accident in which a member was stuck and dragged. At the time, she also took the elevator to other staff and left me with unforgettable memories. The reason is that most of these accidents are related to elevator brakes, or the brake circuit is out of control, or maintenance personnel forget to remove the seal of the short-circuited door lock circuit , or the brake brake torque is seriously insufficient. Cause of the accident May 15, is the brake drum of oil, resulting in a serious shortage caused by brake torque, sad ah.

In addition to installation, maintenance personnel outside the work well occupational accidents occurring, casualties occur in view of the type of elevator, it is substantially the following three:

(1) The passengers were killed or injured when the car was pushed over or crashed. Now this situation is very few;

(2) Casualty accidents caused by falling down the well;

(3) Casualties caused by door-to-door walks and slides.

In a nutshell, most of these casualties are directly related to the hall door.

Second, elevator casualty accident countermeasures

Lift accidents have caused people's attention very early and have tried to improve various safety protection measures as far as possible. However, this effort can only be achieved immediately after the elevator doors are opened and the elevator stops operation immediately. The high-quality control system also has short-circuit gates. When the lock or door interlock relay contacts are stuck, they can only be overhauled and cannot be used as an express train. This is also true of the use of elevators in the world's most famous brands. None of them can well solve the method of preventing the operator from falling into the hoistway when the floor of the elevator car is not open.

Someone once proposed to add a crossbar between each floor hall and car door. When the elevator is on this floor, the crossbar will automatically fall. When it is not in this floor, the crossbar rises, blocking the operator who opens the hall door, preventing falling. Into the well accident occurred; some proposed the principle of reference to car airbags added to the pit; there is a layer of safety net in the pit ( there is indeed this authorized patented technology ) . The proposal and implementation of these programs show that people are constantly considering how to prevent falling into the well accidents through some effective measures. Because the limitations of various conditions have not been finally achieved, there are still human casualties.

After repeated thinking and reasoning, the author believes that "feasible measures to effectively prevent falling into the well accident and shear accident" are still available and easy to implement.

The author proposes to revise GB7588-2003 , to join the control system must detect hall door lock signal, car door lock signal, these two signals are valid, and the other one is invalid, the non-maintenance operation will automatically light shaft lighting, and trigger the alarm alarm, In this way, the operator or the evacuee can be forced to be alert, which can eliminate or significantly reduce the negligence of the operator and the evacuee, eliminate the hidden danger of the accident in the bud, and greatly reduce the occurrence of elevator casualties. There are elevators entering the state of repair, but also lighting the shaft lighting, elevators are all aware that well lighting to maintain long-term use is not much, maintenance staff often open the shaft lighting, forget to close the matter, so not only a waste of electricity, over time The light bulb is also broken. Maintenance automatically lights up, normal automatic extinguishing, more good thing ah. In addition, when an elevator failure causes the elevator to fail to operate, the lighting of the hoistway is also lighted and an alarm is triggered. In the final analysis, the well lighting is subject to program control and the well lighting relay is introduced to control the well lighting.

For the elevator control system, I believe that as long as the door lock is in a short-circuit state, the express train cannot be started. Regardless of whether the elevator is in the overhaul state or normal state, any hall door of the elevator is opened and the car should immediately stop running and issue an alarm at the same time. In addition, when the elevator starts to run after leveling, as long as the hall door is open or the hall door is in a state of adhesion (including short circuit), the elevator should not be started normally, eliminating the possibility of opening the door and walking the ladder.

By judging the inconsistency of the hall door lock signal and the car door lock signal, and the maintenance or fault automatically lighting up the hoistway lighting or alarm, the short-circuit door lock cannot start the express trains to eliminate the possibility of elevator casualties. The innovation or improvement and upgrading of elevator control technology are feasible measures and preventive measures against falling or shear accidents caused by accidentally entering a hoistway or opening a walkway. It is hoped that relevant departments will be able to demonstrate and promote the revision of relevant clauses of GB7588-2003 as soon as possible to improve the safety factor of elevators so as to benefit the society and benefit the people.

Third, the specific program

Scheme principle:

1, the elevator control system to be detected are interlocked hall car door interlock signal, the second signal is inconsistent, 1 second delay and automatically opens the hoistway lighting alarm to trigger an alarm. This forces the operator who opens the hall door to be alert to prevent accidents. The alarm power supply consists of a rectifying circuit and a battery to ensure that the system charges the battery and enables the system to generate an alarm sound in the event of a power outage.

2. When the elevator fails to stop in the non-door zone, the lighting of the hoistway is automatically turned on for one second and the alarm is triggered. Remind trapped people not to sneak in to save themselves.

3. When the elevator changes the inspection operation mode, it will automatically open the hoistway lighting for one second delay , provide maintenance and repair work within the hoistway, provide sufficient brightness, facilitate work, and avoid scratching events.

4. The elevator shall detect the hall door lock signal and the car door lock signal separately each time the elevator starts. No matter whether the hall door lock or the car door lock has a short or sticky connection, the elevator express train cannot be started and alarmed. Prevent the opening operation from causing a cut accident.

5. When the elevator has slipped, or if it stops in the non-gate zone for any reason, the control system must cancel the call instruction and enter the slow lane to find the layer or addressing. It is forbidden to start the express train immediately to avoid the elevator accident.

For elevators that open doors and go ladders, one kind of problem belongs to the aspect of circuit control ( the solution has been given above ) , and the other problem is that there is a problem with the brakes. There are 3 possibilities to cause a trip due to a brake failure :

(1) The mechanical failure of the brake is caused by the mechanical failure of the brake;

(2) The brakes have not been adjusted for a long time, and the wear of the related machinery has caused insufficient braking torque;

(3) The mechanical adjustment of the brake is seriously misunderstood.

When the elevator often appears ± 30mm out of level ground , or even more of this abnormal situation, this obviously belongs to the second or third case. In the initial stage of out-of-plane problems, relevant personnel shall promptly notify the maintenance personnel to make relevant adjustments to avoid the occurrence of slipping accidents.

6. The elevator control system shall detect the leveling error. Error of ± 30mm than 2 times within a certain time (e.g. 60 minutes), the elevator should run as a fault limits, forcing it to maintenance personnel must repair the elevator leveling adjustment tolerance. This will effectively prevent the occurrence of the door-opening slide phenomenon caused by brake mechanical wear or improper adjustment and achieve the purpose of prevention.

In fact, when the system detects that the leveling layer is out of tolerance, an alarm is issued and the elevator is protected. It is entirely possible to stop the operation. For example, when the leveling layer is out of tolerance, the control system sends out an alarm to remind the passengers who come in and go out to prevent the elevator from being raised. Rumbled. When the people to get on the car is completed, as long as the elevator hall doors closed, the elevator is still functioning properly, but in the actual operation of the elevator, if there is 60 minutes twice leveling tolerance, the control system fault should be recorded, and the elevator stops Alarm at the same time. Passengers or property safety management personnel will notify the maintenance personnel to handle the treatment, so that it can largely prevent the occurrence of door-opening and stair-climbing accidents.

Fourth, the proposed amendments to the relevant provisions of GB7588-2003

1. Add hoistway lighting opening conditions in “ 5.9 well lighting” in GB7588-2003 :

1 ) When the elevator control system detects that the hall door interlock and the car door interlock two signals are inconsistent, the lighting of the hoistway will be automatically turned on 1 second delay and an alarm will be triggered (such an emergency unlocking will automatically light up the hoistway lighting;

2 ) When the elevator fails to stop in the non-door zone, the lighting of the hoistway will be automatically turned on for 1 second and an alarm will be triggered;

3 ) The elevator will enter the maintenance state to automatically open the shaft lighting;

4 ) Open it manually.

The use of hoistway lighting relays requires the use of normally closed points to control hoistway lighting so that the elevator can run normally and the hoistway lighting is turned off. When the door lock is detected abnormally, the elevator is faulty, the system is powered off, and the inspection operation is performed to ensure that the hoistway lighting is lit.

2, in the GB7588-2003 "7.7.2 The “protection against shearing” in “amendment” in 7.7.2.1 means that in addition to the case of 7.7.2.2 , if any of the doors in one of the landing doors or doors is open, it shall not be possible to start the elevator under normal operating conditions. Keeping the elevator running, if the hall door interlock is shorted or stuck, the elevator cannot be started again normally after it stops. However, the preparatory operation of the car can be performed. ”

3, in GB7588-2003 added "leveling the elevator control system detects an error requirements", more than twice the error of ± 30mm for a predetermined time (e.g. 60 minutes), the fault should be restricted as elevator. Prevent the brake from mechanical wear or improper adjustment caused by the phenomenon of opening the door.

That is, in "" 14.1.1 of GB7588-2003 Faults that may occur in 14.1.1.1 of the failure analysis :

a) no voltage;

b) voltage drop;

c) wire ( body ) interruption;

d) insulation damage to earth or to metal components;

e) Short circuit or disconnection of electrical components and changes in parameters or functions, such as resistors, capacitors, transistors, lamps, etc.;

f) The movable armature of the contactor or relay does not attract or pull in completely;

g) The movable armature of the contactor or relay does not release;

h) The contacts are not disconnected;

i) The contact is not closed;

j) The wrong phase. "In addition k) Flat floor is poor.

V. Conclusion

The requirements of the safety technical specifications such as the “Regulations on the use and maintenance of elevators” have been effectively implemented, the daily inspections of elevator operations have been intensified, and the implementation of the management system for elevator keys has been strengthened. At the same time, the government should increase safety technical training and supervision and supervision. It is the common responsibility of our elevators for experts to study how to prevent or eliminate the recurrence of elevator casualties through technical innovations or technological improvements and upgrades. Improve the safety factor of elevators, reduce or eliminate the occurrence of elevator casualties, benefit the society and benefit the people.

The information in this article comes from the Internet and was reorganized and edited by China Rescue Equipment Network.