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An air curtain is a device mounted above an open doorway that blows a controlled, high-velocity stream of air downward. It acts as an invisible barrier, separating indoor and outdoor environments to protect occupant comfort and keep out flying insects, dust, and fumes. Berner air curtains adhere to the ASHRAE 90.1 Vestibule Exception, providing energy savings while allowing unobstructed foot traffic and clear visibility. Learn more about air curtains on our Air Curtains 101 page.

Once it is powered on, air is brought into the unit through the intake. The air then enters the fan housing and is accelerated by the fan. This fast-moving air goes into a plenum, which allows for an even distribution of air along the full length of the discharge nozzle. Airfoil-shaped vanes in the nozzle create a uniform air stream with minimal turbulence. The air discharged through the nozzle creates a jet stream to the floor. When mounted properly, approximately 80% of the air returns to the intake side of the air curtain, and 20% goes in the opposite direction. Visit our Air Curtains 101 page to learn more about Berner air curtains.

The air curtain must span 100% of the opening width, so the first step is an accurate measurement of your door or opening. Beyond width, the right model depends on door height, the temperature differential between indoor and outdoor environments, traffic volume, and application type (entrance, dock door, freezer, or service counter). Use Berner’s Air Curtain Selector Tool for guided sizing or contact a Berner specialist for high-demand or unusual openings.