Ключевые слова: bituminous, black, central, clean, coal, coal burning, cube, dark, deposits, ecology, effect, energy, environment, extract, extraction, fuel, fuels, gas, heat, heating, helmet, hot, industry, lignite, load, loading, manufacturing, material, metallurgical, mine, miner, mineral, mines, nature, pile, power, power station, resources, safety, safety helmet, stone, things, tools, types, uses of, yellow helmet,