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Even to those who study mining disasters, last week’s explosion in Soma, Turkey, was shocking. The (26) cause of the explosion is unknown, but it is thought to have started with a spark from electrical equipment that ignited coal dust or methane. The (27) is nearly 300, and dozens of people are still missing. While citizens in Turkey respond with angry protests, engineers around the world are working to prepare fleets of robots to help with the next disaster.
Mine explosions like the one in Turkey are (28) caused when methane gas builds up and (29) , and the flames are carried quickly by flammable coal dust hanging in the air. Other countries like the US and the UK have adopted relatively low-tech (30) prevent explosions and keep them from spreading, such as putting steel boxes around (31) to contain sparks, or spreading stone dust throughout the mine to dilute the coal dust and (32) the flames.
But when things go wrong, a burned-out mine can be a dangerous place for rescue workers. So mine safety engineers want to send robots to scout ahead of humans to test the air quality and find safe (33) to trapped survivors, and perhaps even carry them out. Such efforts have been (34) challenges. After the Crandall Canyon mine in Utah collapsed in 2007, killing six miners, a camera scout robot got stuck in a borehole.
There are signs that the technology is (35) . This week, the US Office of Mine Safety and Health Research called for proposals for robots that can be lowered into boreholes, explore up to about 1,000 meters ahead of rescue teams, and act as pack mules.