In the field of Cleanroom environmental control, AHU (Air Handing Unit) and HVAC system are two concepts that are often mentioned but easily confused. 

A clean room pass box is a small, enclosed transfer system designed to move items into and out of a clean room without introducing contaminants. Often installed in walls or doors between different zones, the pass box ensures that the delicate balance of particle contamination is maintained.

The Importance of Clean Rooms in Semiconductor ManufacturingSemiconductor manufacturing is an intricate process that requires an extremely controlled environment.

Cleanrooms are typically equipped with air showers, cargo showers, transfer windows, HEPA Boxes, Clean Benches, and FFUs.