SOLUTIONS
Revolving Doors are designed so that there is a constant airlock between the two environments.
Usually the door is made up of 3 to 4 door leafs that rotate around a central point. This ensures the constant movement of people is possible while reducing the flow of air between the two areas. This also greatly reduces the cost of heating and the cooling of both environments.
Revolving Doors can be designed to revolve only one way and movement thresholds can be put in place to stop them from spinning too fast and creating a health and safety risk to users.