Two victims and a rescuer suffered from anoxia in a sewerage system manhole
|[Description of the Accident]|
occurred during the work to lift a drain pump through a manhole in a
sewerage construction work.
1. Although boring survey results had been provided by the order-placer, neither the general contractor nor the subcontractor recognized the working site as presenting a fear of anoxia.
2. The workers failed to measure the oxygen content of the inside and to carry out ventilation measures before entering the manhole.
3. An operations chief was not appointed.
4. Neither special education nor rescue training concerning work at sites with the danger of anoxia was provided to workers.