Ключевые слова: background, blue, boiler, building, chemical, chimney, coal, communicate, construction, electric, electrician, electricity, emissions, engineer, engineering, factory, flue, fuel, gas, hand, hard, hardhat, hat, helmet, holding, industrial, industry, lignite, man, manufacturing, pipe, plant, pollution, power, radio, red, refinery, senior, smog, smoke, smokestack, stations, steam, talkie, technician, tower, walkie, white, worker,