An aseptic processing workstation can include a processing chamber and an airflow circuit passing through the chamber. The circuit can include an air supply fan, an air return fan and a restriction element. The chamber is located in the circuit between the air supply fan and the air return fan. The restriction element is located in the circuit on the other side of the air supply fan and the air return fan to the chamber. The workstation can include an air inlet fluidly connected at a first connection point to the circuit via inlet valve means. The first connection point is located between the restriction element and the air supply fan. The workstation can include an air outlet fluidly connected at a second connection point to the circuit via outlet valve means.