Air curtains
An air curtain is a powerful fan heater with a flat, clearly directed airflow, installed above or outside the door (window) or any other openings. Air curtains are necessary for the separation of zones with warm and cold air with open apertures and are used to keep heat and eliminate drafts in rooms or to save chilled air in industrial refrigerators. Air curtains also serves as an excellent protection against drafts, in the cold season can additionally heat the room, and in the hot, working in the ventilation mode, to keep cool air. The curtain also protects individual rooms from getting insects, dust and exhaust from outside, and can also serve as a barrier to getting unpleasant odors and other types of emissions on the street or other external environment.