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Special equipment is essential in industrial production; at the same time, due to the high risks associated with its use, it represents a key focus and challenge in safety supervision. Starting today, we are publishing Yuan Hualin’s lectures on safety in lifting operations, in the hope that they will be useful to professionals in this field. Author profile: Yuan Hualin (female), professor in the Department of Safety Engineering at Capital University of Economics and Business, and supervisor for master’s students. Mainly engaged in teaching and research in areas such as mechanical safety, lifting safety, safety science, and theories of professional safety education. The high safety risks associated with lifting machinery: Human production activities and daily life rely on the need for materials, which necessitates large-scale material handling. Lifting machinery are mechanical devices used for such material handling tasks. In modern production, lifting machinery plays an important role not only in material transportation, being widely used for conveying, loading and unloading, construction work, and warehousing, but it is also directly involved in the production processes, such as the forging and heat treatment of large components. The use of lifting machinery **improves work efficiency while reducing the workload on workers. In recent years, the functions of lifting machinery have been extended and applied to various amusement machines. Those large-scale passenger amusement rides that can lift and rotate, and whose operation principle is similar to that of lifting machinery, have become attractions that draw visitors thanks to their varied movements and thrilling features. They enrich people’s entertainment options and improve their quality of life. The use of any machinery comes with safety risks, and lifting equipment designed to achieve speed, efficiency, and high lifting capacity is inevitably faced with increasing safety hazards. According to incomplete statistics, among operations where accidents occur frequently, lifting accidents are numerous, have severe consequences, and result in heavy economic losses; they thus remain special equipment that is a focus of safety monitoring. The high risk associated with lifting machinery is determined by its unique mode of operation and working characteristics. The operating characteristic of lifting machinery is periodic intermittent work. Its working principle is as follows: the loading device that carries the materials is supported by a large metal structure; through the separate or combined movements of various working mechanisms, the materials are lifted and moved within a certain range in space, then placed in the desired location as needed, and the device returns to its original position empty, ready to carry out another cycle of material handling. The entire work cycle requires close coordination among three parties: ground commanders, riggers, and crane operators. From the perspective of occupational safety and health, lifting operations have the following characteristics: 1. High potential energy of the materials. The loads handled during lifting operations are heavy, usually in the tons, with some reaching several hundred tons. The lifting and handling process is the movement of suspending heavy objects in the air. Due to the large mass and high position of the load, it possesses a very high potential energy. Once an accident occurs, high potential energy is quickly converted into high kinetic energy. 2. Multidimensionality of movement: Unlike other fixed mechanical devices, cranes need to move as a whole during operation, and the lifting and transporting process is achieved through the combined movement of multiple mechanisms. Every installation contains a large number of moving parts with complex structures, various shapes, different modes of movement, and changing speeds. Coupled with the movement of the load in three dimensions, this results in numerous and dispersed sources of danger in lifting machinery. 3. Large scope of operation: The massive metal structure of the crane spans across the workshop or work area, rising above other equipment, facilities, and workers. By lifting materials, the crane can move partially or entirely over a large area while carrying a load. As the area of operation increases, so does the range over which hazards can occur. 4. Group nature of the task: The process of lifting operations involves a series of steps (such as the ground riggers securing the load, attaching hooks, and unloading it; the crane operator controlling the crane to lift the materials; and moving the load to the designated location according to instructions from those on the ground) to lift the items into the air. Every lifting cycle must be carried out through teamwork; any issue at any stage can lead to an accident. 5. Complexity of operating conditions: In indoor cranes, there are many ground-based equipment units and a high concentration of personnel ； Cranes outdoors are subject to weather conditions and site constraints ； When working at night, it is affected by the lighting conditions within the work area. Furthermore, there is a wide variety of materials, including finished products, bulk materials, liquids, and solid-liquid mixtures, all with different forms. Furthermore, mobile cranes are also affected by a variety of factors such as the terrain and the surrounding environment. In short, the special nature of lifting and handling operations, along with the unique structure and movement patterns of lifting machinery, gives rise to numerous risk factors, making safety issues particularly prominent. As people’s awareness of safety increases, expectations regarding the safety of working conditions are rising, and greater attention will be paid to the safety of lifting machinery.