Sealing device for sealing at least one zone of underpressure or overpressure adjoining a moving surface that includes at least one sealing element, positionable opposite the moving surface to form a front and a rear, with respect to a surface running direction. The sealing device includes a sealing section located at the front and a ventilation section located at the rear. The sealing section is structured to sealingly interact with the moving surface; and the ventilation section is structured and arranged to form a gap with the moving surface that widens in the surface running direction.