Wireless systems that locate trapped miners and send them text messages are being tested by safety regulators in the United States.
The U.S. Mine Safety and Health Administration is evaluating the systems, one of which pinpoints the location of individual miners and the other that offers a means of communicating with them.
"We will test these systems -- as well as other promising technologies that arise -- to provide miners and mine operators with useful data on the effectiveness of devices such as these in making mines safer workplaces," the agency said in a release.
One of the systems is based on a personal transmitter worn by the miner that sends out a signal unique to each individual. The other device is a personal receiver that allows rescuers to send text messages to the miners.
Both were developed in Australia by Mine Site Technologies and operate on a network of wireless radio transmitters installed in the tunnels.
The MSHA said it still had concerns about keeping the network operating after an explosion or collapse.
Copyright 2006 by United Press International
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