Pass box is one of the clean room systems, which is used to transfer materials from one side to other side through controlled environment in order to avoid airborne cross contamination. As the name states itself, the primary and only work of a pass box is to pass material from one side to other without raising contamination concern and if any particulate matter presents on the material surface, it swipes away during the operation. Interlocking door mechanism is the prime feature of a pass box, when door at one side is open the door at other side remains closed. It is popular with other names such as cleanroom pass through, clean transfer window and transfer hatch; in addition, it is widely used in microbiology laboratories in food, pharmaceutical and chemical industries.
A pass box is designed in two different types; static and dynamic, it is the user specific requirement which decides the right design configuration. The difference between these two is explained as:
DYNAMIC PASS BOX (DPB)
A dynamic pass box is fitted between classified and non-classified areas. Material is passed through vertically HEPA filtered air.
STATIC PASS BOX
Static pass box on the other hand is fitted only between two clean room areas and has no air supply or extract. It is also known as passive pass box and equipped with UV light.