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Analysis of crane accident types and causes: An analysis of the crane operation process shows that the special structural design of crane machinery, along with the manner in which it moves objects, presents numerous risk factors; these risk factors are the origins of accidents. There are visible and potential various dangers, and different types of risk factors often overlap. The main types of lifting accidents include the following: 1. Injury caused by falling heavy objects. There are various reasons for the fall of heavy objects; common causes include damaged lifting equipment or containers, loose or slipping loads due to inadequate securing, improper hooking that leads to detachment, and sudden loss of power in electromagnetic clamps, resulting in the drop of the materials being lifted. Failures or damage to the components of the lifting mechanism (especially brake failure, broken wire ropes or hooks, etc.) can all pose a risk of heavy objects falling. Furthermore, the fall of heavy objects can also cause secondary injuries due to hazardous materials being lifted. For example, high-temperature liquid metals, as well as hazardous materials that are flammable, explosive, toxic, or corrosive, can all cause burns, dust-related injuries, toxic exposure, and other harm due to the physical and chemical properties of these materials. 2. Loss of stability in the crane. There can be two reasons for a crane to lose stability: one is due to improper operation (such as overloading, too rapid movement of the boom, etc.), uneven placement of the legs, or ground settlement, which causes the crane to tip over as a result of an imbalance in forces ； Secondly, due to slope or wind loads, the crane slides along the inclined road surface or tracks, resulting in unwanted displacement, derailment, or overturning. 3. Failure of metal structures: Massive metal structures are important components of various bridge cranes, tower cranes, and gantry cranes. Acting as the framework of the entire crane, they not only bear the weight of the crane itself and the load it lifts, but also define the three-dimensional space in which lifting operations take place. Due to the different compositions of the metal structures of cranes, the forms of damage to these structures also vary. For example, in bridge cranes and gantry cranes, the deflection of the main girders may exceed acceptable levels or the legs may collapse; whereas in tower cranes and jib cranes, the jibs may fall or the towers may topple over. The failure of metal structures often leads to severe injuries, or even tragic deaths on a large scale. 4. Injuries caused by falls from heights: Cranes are large in size; the main beam of a typical bridge crane is over 10 meters high, while tower cranes and gantry cranes can be as tall as several dozen meters. To ensure a clear view of the work site, the driver’s cab is often located at a high position on the metal structure, and many equipment items are also installed at heights. Tasks such as the disassembly and assembly of tower cranes when they are moved from one location to another, the maintenance and repair of equipment mounted at high heights, as well as safety inspections and measurements—all these activities that require people to climb to high places carry the risk of falls and injuries. 5. Squeezing and crushing injuries: Some bridge cranes lack proper safety passages on both sides of their tracks, while the radius of rotation of the boom assemblies in tower cranes or truck cranes is too small compared to the distance from nearby building structures; this can result in squeezing injuries to other people who are still in those areas during the operation or rotation of the cranes. Due to the mobility of the crane as a whole, operational errors of the driving mechanism or brake failure that lead to rolling away can cause collisions or crushing injuries to people. Mobile cranes operating on roads may also be involved in traffic accidents. 6. Electric shock injuries: Most cranes are powered electrically, either through cables or by using exposed wires for power supply. Electric shock injuries can occur when any part of the crane or the load gets too close to live electrical components or comes into contact with them. Even with mobile cranes, accidents occur from coming into contact with high-voltage lines when working near power lines. Direct electric shock or injuries caused by step voltage can lead to electrical accidents. 7. Other mechanical injuries: Injuries such as entanglement, crushing, or puncturing caused by contact between certain parts of the human body and moving components; injuries resulting from the spraying of high-pressure liquid due to damage to hydraulic components or pipelines; injuries caused by flying debris resulting from damaged rotating parts; and injuries resulting from the recoil force of pulling cables. These types of injuries that occur in ordinary machinery can also happen during crane operations.