JICOSH was closed in 2008. For further information, please contact JISHA.
JICOSH Home > Case Studies > Case No.93
Case No.93

Caught by jib being dismantled from a mobile crane



Click Here
[Description of the Accident]

This accident occurred during work to dismantle an auxiliary jib on a mobile crane that had completed its work.

The president who was operating the crane first tried to pull out the pin of the jib. As he had difficulties in pulling out the pin, however, a worker standing nearby took a turn. As a result, the pin suddenly came free and the jib collapsed at the same time. The victim was caught and struck in the chest and died.

While the instruction manual had specifically called for attaching a pendant wire to lift the auxiliary jib in order to prevent the falling of the jib when the pin is pulled out, this was not done as instructed.


[Causes supposed]

1. While it was necessary to install a pendant wire to prevent the jib from falling in order to avoid any danger of the jib falling when carrying out jib dismantling operations, the workers were carrying out work without doing so.

2. No danger prevention measures had been taken, such as using another crane to lift the jib, steadying the jib on a safety block, etc.

3. As this was a large-sized crane, considerable skills and experience were necessary in operating the machine. However, no other workers except the company president were accustomed to the dismantling operation.


[Type of business] Construction
[Caused by] Mobile crane
[Type of accident] Hit by flying or falling object
[Number of victims] One fatality
toptop