According to the agency, many accidents occur when power to a cable is restored by someone other than the worker making repairs, and without that person’s knowledge.

To help prevent future accidents, MSHA recommends mines de-energize any damaged trailing cable found and remove it from service. Once the cable is disconnected, the disconnecting device should be locked out and tagged out prior to repair work on the damaged cable.

Once repairs are completed and before the circuit is re-energized, workers should ensure that all people working in the area are in a safe location. Thorough communication before resetting the affected breaker is also a crucial step.

Finally, to help prevent cable damage, the agency suggests protecting cables by always moving them to a location where they cannot be run over by mobile equipment.

One recent US death that may have been prevented by using these best practices and by locking and tagging out involved electrician Nathan Dove, 24, who died in May 2008 after he failed to de-energize a shuttlecar before beginning to make repairs.

Dove was planning to work on a No. 2 Joy shuttlecar May 18 at Massey Energy’s Aracoma Alma No. 1 operation in Logan County, West Virginia, when he cut into an energized 480-volt phase lead on the car’s trailing cable at the reel area. At the time of the incident, he was attempting to re-enter the cable into the reel where two phase leads had become damaged from electrical arcing.

“According to a company document regarding West Virginia state law on lock and tag-out policies, Nathan Dove was familiar with the requirements for locking and tagging out equipment,” MSHA pointed out in its final investigation of the incident last April.

“Once Dove, the section-qualified electrician, smelled the odor of burning cable and initially observed damage to the cable for the No. 2 shuttlecar, the power to the shuttle car should have been disconnected, locked out and tagged.”

The agency also found that no one working with Dove witnessed him go to the power centre to de-energize the unit and did not hear him communicate with others to request the action be completed.

“The accident investigation team could not determine why the repair to the cable continued without first being de-energized, locked out and tagged,” MSHA noted.