According to the Mine Safety and Health Administration (MSHA), a miner at a sand and gravel operation was recently moving an excavator from the pit to an area where the mechanic could work on a loose bucket attachment pin. As the excavator was traveling parallel to overhead 4,160-volt power lines, the pin came loose.
The operator swung the boom to the right to avoid dropping the bucket in the path of travel. In doing so, the boom came close enough to overhead power lines that an arc occurred.
MSHA recommends the following best practices to avoid this type of hazard:
- Ensure safe access is available when moving equipment.
- Keep booms/beds/buckets on mobile equipment stowed in safe travel mode to avoid coming into contact with energized power lines and overhead obstructions
- Correct deficiencies on mobile equipment before movement or placing it into service.
- Ensure that potentially hazardous conditions such as overhead powerlines are conspicuously marked.
- Deenergize overhead powerlines if there is a possibility of an arc when mobile equipment is operating or traveling nearby.