MINE FIRE — evacuate.

These words, broadcast via an Australian-designed underground paging device, provided sufficient warning for more than 50 miners at Cyprus Plateau Mining Corporation’s Willow Creek mine in Utah, USA, to safely evacuate the mine when a fire was detected late in November last year. The fire, subsequently extinguished when CPMC plugged all mine entries to starve it of oxygen, halted coal production from the mine until February this year. Longwall operations had not recommenced when Australia’s Longwalls went to press, however, a visual inspection of the longwall equipment indicated it had sustained minimal physical damage.

US mining and government safety officials praised the PED system, supplied by Sydney-based Mine Site Technologies Pty Ltd, for ensuring Willow Creek’s miners were similarly unharmed.

And a Salt Lake Tribune headline screamed: “High-tech alert system sped workers to safety”

Willow Creek was attracted to MST’s PED system because of the productivity and efficiency benefits it offered. It bought PED transmitters and BeltPED receivers, worn on miners’ safety belts, to enable fast and reliable underground tracking of, and one-way communication with, personnel.

A senior official from the national Mine Safety and Health Administration (MSHA) said the 45-minute evacuation was “remarkable”

“Because of that we’re looking at making some form of the PEDs mandatory,” he said.

MST was established in 1989. The PED system is an “ultra low frequency, through-the-earth” paging and remote control system which uses ULF and a high-power transmission unit to propagate a signal through rock strata.