human passage

Heat and mass flow between cold and warm environments due to the pressure difference between both sides. This exchange causes a loss of energy and human comfort in the buildings. The indoor air quality (IAQ) also reduces because of the passage of dust, odour, insects and bacteria along with the fluid across a doorway. To minimise this heat and mass flux and to maintain IAQ, an air curtain is often used as an artificial separation barrier in public and industrial buildings.