It is the fourth week into the new year and already three coal miners have died, the most recent in Kentucky. This is Kentucky’s first, and hopefully last, mining death this year.

Nathan Phillips worked for the Dokiti Mine in Webster County Kentucky. He was using a continuous digging machine underground and was pinned. The Dokiti Mine is owned by Alliance Resource Partners which owns multiple mines in the surrounding area and nearby states.

Last year mine safety officials issued rules that require motion sensor equipment to be installed on these continuous miners. Miners wear sensors that can be picked up by the machines and if they got too close to the machines the machines would start to give off warning alarms and ultimately shut down if the workers got to a certain point. Many machines that were in use already had such devices installed on them even though the rule gives exemption to some older models of machines until 2018. Since 1984 there have been about three dozen deaths involving continuous mining machines, and the rules were put in place to try and prevent even more injuries or deaths.

The United States Labor Department’s Mine Safety & Health Administration does not yet know whether the particular machine Phillips was working with had a detector or not. Alliance has not commented but their mines have been used by Mine Safety officials as demonstration sites for the proximity detectors in the past.

In 2015 there were 11 deaths in the coal mining industry which was a record low, and that there have already been three this year is “troubling”, says the head of the Mine Safety and Health Administration Joe Main. He is calling for his agency to step up enforcement efforts and education efforts.