Extruding, striking, hooking and hanging, falling, derailing, collapsing, tilting, fracturing and getting an electric shock etc. are the common accidents of the hoist machinery.
Such as the goods gets off from the hook ,the rope fractures , the lifting goods strikes workers, the rope hurts people, the crane slides ,and the crane falls down from upper airspace; 
Operation factor, equipment factor and environment factor are the main reasons of the accident.
1. operation factor
a. the wrong lifting way, the goods gets off from the hook because of loose binding and the goods scatters and swings to hurt people
b. Disobey the operating rules, such as lift with overloading, casualty and damaged equipments when people work in danger zone.
c. colliding because of inadequate direction and incoordination
2. Equipment factor.
a. The lifting appliance is out of control. For example, the goods fall because the hook, grab, rope and nets are damaged.
b.Control system and safety device are out of control. For example, the impacting and extruding of heavy object because the brake looses control.
C.The intensity of parts is not enough. For example, the falling of tower crane
d. Electric shock because of the damaged electrical equipment.
e.The derailing accident of overhead crane because of gnawing rail, excessive abrasion and bending
 
3. Environment Factor
a. Strong natural disasters such as thunder, gust, tornado, typhoon, earthquake ect. 
b.Colliding and extruding accident because of crowded and disordered site
C.Colliding accident because of the light is not enough and the vision is blocked.