An air curtain, also known as an air door, employs a controlled stream of air aimed across an opening to create an air seal. This seal separates different environments while allowing a smooth, unhindered flow of traffic and unobstructed vision through the opening. Because air curtains help to contain heated or conditioned air, they provide sizeable energy savings and personal comfort when applied in industrial or commercial settings. Air curtains also help to stop the infiltration of flying insects and dust.