The main cause of explosions in mines is methane gas or firedamp. In the early days explosions were caused by an open flame or a spark. Even methods of testing for gas were dangerous. A "fireman" clad in damp clothing crawled into a gassy area and waving a pole with a candle on the end he ignited the gas. The effect of a methane explosion can be increased if the coal dust is ignited too. Shelves of stone dust are placed across roadways so that the dust falls when an explosion occurs, therefore smothering the flames.
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