Accident with lifting rock up by excavator

Any accident foreseen in this frame?

With a hydraulic excavator, an operator worker is digging a gutter for a city water pipe in a 4.1-meter wide road. He has dug out a boulder weighing approx. 200 kg. He is lifting it up with a chain and wire rope fixed to the bucket to load it on a truck, while another worker watches the work nearby.

Now what accident do you anticipate from this picture? 

This is the accident resulted!

The boulder slipped off the chain loop, because it was hung with a single chain and lost equilibrium. The falling boulder hit the worker and killed him.




Tips for forestalling similar accidents
1. Lifting an object with a bucket is not the primary application of hydraulic excavators or the like. If it definitely becomes necessary to use them that way, observe the instructions set forth in the Article 164 (164-2-1 and 2, 164-3) of Regulation on Industrial Safety and Health.
Furthermore determine a set of signals for the work like the one cited above and appoint a signalman in advance, whose instructions the others follow in the work.
2. Never allow anybody to get close to the area at a worksite where he/she might be injured, should a hung object fall off.
3. When slinging work is required, thoroughly examine a sling, slinging work process, etc. beforehand and make sure that the conclusions reached be followed without fail.