Abstract: An apparatus for producing an air curtain comprising a central opening bounded by a frame on the top, bottom, and sides which defines internal channels which fluidly communicate with one another. The bottom and sides of the frame define apertures of varying diameter proximate to the lower portion of the central opening. The apertures are arranged in an array whereby rows of apertures more closely proximate to the front edge of the central opening have diameters greater than the diameters of the apertures in rows more closely proximate to the rear edge of the central opening. Air is drawn into the channels through the apertures, and the array of apertures produces a forwardly biased pressure gradient, the result of which is to cause a stream of air being expelled downwardly from the top of the central opening to ramp or curl forwardly toward the front edge of the central opening as that stream of air traverses the central opening.