Air Curtains is a device that is used to be able to prevent air or contaminants from being able to travel from one open space to another. It works by separating the two different temperature zones, it does this generally by having one of the downward facing blower fan over the entrance of a room and separates it out with an invisible curtain or air. The benefits of having one of these in the entrance is that it helps to prevent the warm air leaving the building in the winter, similarly in the summer it helps to keep the cooler air in.
Air Curtains tend to be used and mounted above an entrance where the doors for the entrance are required to stay open for operational purposes. Another benefit of having one of these air curtains above the entrance is that it also helps with being able to keep flying insects out of the building, as it creates a forceful turbulence barrier which flying insects will struggle to infiltrate through.