1. Construction hoisting machines typically have large structures and more complex institutions, the job is often a movement in several directions at the same time during operation, technical difficulty.
2. Lifting heavy things are varied, load is variable. Some heavy objects weighing hundreds of tons, large size and irregular, there are bulk and heat integration of inflammable and explosive dangerous goods, etc, make the process of lifting complex and dangerous.
3. Some hoisting machinery (only a construction elevator, etc), you need to directly carrying passengers to do vertical movement, which directly affect personal safety.
4. The building hoist needs to be run on a larger scale, larger space that once caused the accident, the area affected is large.
5. Jobs often require more coordination, commander, demanding things like operator and rigger.