Emergency and quick operational radio communications in Utah Power and Light Company´s Deer Creek Coal Mine

An underground radio communications system has been developed and installed in the Deer Creek Coal Mine near Huntington, Utah. The minewide radio communications system provides emergency communications to mine personnel working along the face, belt lines, man and material entries, returns and designated escapeways. The system also provides quick communications between the surface monitoring center and key personnel throughout the mining complex. The radio system utilizes two robust radio signal propagation modes to provide communications throughout the mine. In the first mode, low-conductivity seams of coal, trona, potash, quartzite and gilsonite surrounded by more conductive rock layers form natural waveguides for low-attenuation-rate transmission of radio signals. In the second mode, conductors, AC power distribution cable, conveyer belt structures, steel pipe, rail, etc. form low-attenuation-rate waveguides for distribution of radio signals. The entire radio system meets intrinsic safety requirements and is composed of three basic elements: a base unit (with remote audio capability), transceivers (with different housings which are specific to the application), and repeaters