Federal regulators have proposed that equipment used to haul coal in underground mines be required to have technology designed to prevent miners from being run over or crushed.
Such a warning system might have prevented the most recent death at an underground coal mine in Kentucky, according to the U.S. Mine Safety and Health Administration.
In that case, a miner operating a machine called a ram car ran over Eli Eldridge. The fatality happened Dec. 16 at Highland 9 mine in Union County, which was operated by a subsidiary of Patriot Coal.
Eldridge, a mechanic, had been walking through the mine to check on needed repairs when he was hit.
MSHA concluded that the Highland mine didn't have effective safeguards to keep workers from being hit by moving equipment.
Patriot closed the mine soon after for economic reasons.
The technology covered in the rule MSHA proposed this month is called a proximity-detection system. It uses electronic sensors to detect motion and the distance between a miner and a machine.
The systems activate audible and visual warnings if a machine comes too close to a miner, and they are designed to stop a machine automatically before it hits someone.
Under the proposed rule, companies would have to install the technology on machines such as ram cars and scoops, which are used to move coal from the face — where it's being clawed out by continuous-mining machines — to conveyors that carry it out of the mine.
"This proposed proximity-detection system rule would better protect miners from being crushed or pinned in the confined underground mine spaces where large equipment is constantly in motion," MSHA chief Joseph A. Main said.
From 1984 to 2014, 42 miners died from being hit by machinery or crushed against the mine wall, MSHA said in a news release.
An additional 179 underground miners were injured in such accidents in that period, MSHA said.
Some mines already use the proximity-detection technology, but many would have to upgrade if the rule is implemented.
MSHA estimated that as of June, 155 of the more than 2,100 coal-hauling machines in use in the country had proximity-detection systems.
However, it's clear that the technology works because some mines already use it, MSHA official Kevin Stricklin said in a news release.
Companies would have as long as three years to put such systems on all machines.
As part of the rule, the agency requested comments on whether non-coal mines should be required to use such systems.
MSHA finalized a requirement this year for continuous-mining machines to have proximity-detection systems.
MSHA has recorded one mining death in Kentucky this year. It happened at a Pike County surface mine in May, when Roy Mullins, 45, was crushed between a road grader and a tractor-trailer.
There have been no deaths at underground coal mines in Kentucky this year, according to the agency.
Eldridge's death was one of two at Kentucky coal mines in 2014. That matched record-low fatality totals in 2007 and 2013.