Generally speaking, the lifting injuries include extruded, falls, falling heavy objects, collapsed, broken, overturned, electric shock, impact accidents. Each accident is related to its working environment, which were caused by the human factors, or by the defective equipment, also by the both of them.
The prevention for the extrusion accidents
The crane (gantry crane)extrusion accident and how to prevent usually include the following three conditions:
The first case, the squeeze happens between the crane body and the fixed objects or the buildings around. This kind of accident usually occurs between the rotating crane or traveling crane and the fixed objects around. For example: the end beam of the overhead crane extruding the column or the walls of the surrounding buildings; the rear parts of the tower crane or the mobile crane squeezing with the other facilities. Many incidents occur due to the limited space, the victim was in the blind angle of the driver’s vision or lacking of the observation by the drivers. Therefore, the appropriate space between the machine and the surrounding buildings should be placed ahead of time and prohibit passing through while operation. 
The second case, the squeeze happens between the spreader, heavy lifted objects and the fixed objects or the building around. In this regard, firstly the reasonable arrangement of the field and stacking heavy objects are necessary. The goods should be stacked in the appropriate clearance, the large components and goods easy to roll and tip over need to be laid in a reasonable position and facilitate to carry. Secondly, the chosen spreader and lifting hook should suit to the hoisted objects, bundling and hanging reasonably to prevent the rotation in the air or falling. Ban dragging the rotating heavy objects with hand directly. The signal commanding officers must be in line with the original lifting program.
The third case, the squeezing accidents happen between the self structural parts of the crane or the lifting machine. For example the squeezing incidents between the crane turntable platform and other components were found by the inspected and maintained personnel. The construction elevator owns more problems in the field of the material lifting machine mainly because of the incompletely guarding device such as no hoisting stopper, no protective handrails and doors. The protective measures include: choosing the proper position to manipulating the hoisting mechanism; the passing channel should be closed and no passing through for the unsealed cage; equipping the protective railings for the entrance channel; pay more attention to avoid head-banging as the maintenance approaching the top limit; falling down the bridge box and counterweight to avoid accident as the pit operation.