Ключевые слова: air, air conditioner, air duct, air pollution, air vehicle, atmosphere, blue, building, clear, climate, clouds, concepts, condenser, copy space, day, ducts, engineering, environment, equipment, exterior, factory, fuel and power generation, heat temperature, hvac, industry, infrastructure, innovation, large, maintenance, manufacturing, metal, modern, no people, outdoors, pipe tube, pipeline, piping, roof, rooftop, shiny, sky, social issues, steel, structure, sunlight, sunny, systems, technology, tube, ventilation,