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Methane Injury-Risk at the Russian Mines

Conditions are given concerning the development of methane-bearing coal seams in Russia, the chronology of injuries from explosions and outbreaks of methane-air mixtures at the Russian mines for a quarter of a century of developing coal seams at the nine deposits. The emergency was studied in 174 mine incidents, which occurred mainly at the mines of Kuzbass, Vorkuta coal deposit, Eastern Donbass, Chelyabinsk basin, Primorye and Sakhalin. Emergency objects - excavation areas, preparation faces and mined-out areas of the mines. The sources of ignition of methane-air mixture are drilling and blasting works in the faces, malfunctioning of electrical equipment, frictional sparking, endogenous fires, and smoking in the mines. The most injury-risk for methane are steep and steeply inclined mines. The need in the scientific substantiation of the decisions taken for prevention or reduction of the methane injury-risk at the mines is noted in the article. An important role is assigned to the choice of ways to achieve this goal considering the geological and mining conditions of the development of gas-bearing coal seams. As an example, the conditions, methods, and parameters of mining operations at the excavation areas of four mines are given, where occurred the catastrophic explosions of methane-air and methane-dust-air mixtures. The reasons are gross violations of safety rules during mining operations, incompetence of the mine engineering personnel, design, and control organizations in matters of safety during the underground work at the gas-hazardous mines with an extensive network of workings. This resulted in the death of miners and mine rescuers, the destruction of mine workings, equipment and devices, underground fires. Recommendations are given for reducing the level of methane injury-risk at the methane-rich mines.