A mining accident is an accident that occurs during the process of mining minerals. Thousands of miners die from mining accidents each year, especially from underground coal mining, although hard rock mining is not immune from accidents. Coal mining is considered much more hazardous than hard rock mining due to to flat-lying rock strata, generally incompetent rock, the presence of methane gas, and coal dust. Most of the deaths these days occur in developing countries, especially China, and rural parts of developed countries.
Mining accidents can have a variety of causes, including leaks of poisonous gases such as hydrogen sulfide or explosive natural gases, especially firedamp or methane,dust explosions, collapsing of mine stopes, mining-induced seismicity, flooding, or general mechanical errors from improperly used or malfunctioning mining equipment (such as safety lamps or electrical equipment). Use of improper explosives underground can also cause methane and coal dust explosions.