Electrical earthing in coal mines - Health and Safety ExecutiveNational Coal Board 1986. National Coal Board. Electrical earthing in coal mines. NCB Headquarters Technical Department, 1986, 45 pp. Information.photos of electrical earthing in coal mines,Coal - Photos - The Big Picture - BostonJan 30, 2012 . Mining for coal is one of the world's most dangerous jobs. . Over 40% of the world's electricity is generated by burning coal, more than from any other source. . could be swallowed by a fresh fire-induced crack in the earth.
photos of electrical earthing in coal mines