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MNM Serious Accident Alert Underground - Electrical

Underground – Marble - A truck-mounted crane, operated by a certified crane operator (contractor), contacted a 25K volt incoming power line at the surface operations of an underground mine. The crane was being used to transfer construction material onto the truck. The accident occurred on March 13, 2017.

Best Practices

• Perform a job task analysis prior to beginning work.
• Post warning signs to alert miners of the location and danger of the high voltage power lines.
• Always give hazard awareness training to the miners which address the hazards specific to the job being performed.
• Position miners as "spotters" to alert equipment operators of the proximity of their equipment to energized powerlines.
• Install high visibility spheres on energized lines to help make the line location obvious to all workers.