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A safety lamp is any of several types of lamp that provides illumination in places such as coal mines where the air may carry coal dust or a build-up of flammable gases, which may explode if ignited, possibly by an electric spark. Until the development of effective electric lamps in the early 1900s, miners used flame lamps to provide illumination. Open flame lamps could ignite flammable gases which collected in mines, causing explosions;

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