A pass box, also known as a pass-through box or pass-through chamber, is a piece of specialised equipment used in cleanrooms, labs, pharmaceutical facilities, and other regulated settings. Its principal function is to permit the flow of goods or objects between two regions with varying levels of cleanliness while reducing the danger of contamination.
Here's how a pass box typically works:
Design:
A pass box is often a tiny, enclosed compartment with two entrances on
either side. These doors are interlocked, which means that neither can be open
at the same time. Electronic locks or mechanical interlocks may be used on the
doors to ensure that only one door is open at any given moment.
Installation:
Pass boxes are often installed into the walls or barriers that separate
the two areas that must be linked. They can be flush-mounted or
surface-mounted, depending on the needs of the facility.
Operation:
When an operator wants to move materials or objects from one side of the
pass box to the other, they open one door on their side of the pass box. This
action causes the interlock mechanism to lock the opposing door, preventing
both doors from being open at the same time.
Transfer:
The operator can then move the items into the pass box and close
the door on their side. After closing and locking the door, the interlock
mechanism releases the door on the opposite side, allowing someone on the other
side to access it and recover the contents. This method guarantees that no
direct airflow exists between the two environments throughout the transfer,
lowering the danger of contamination.
Pass boxes are widely employed in sectors where cleanliness and
contamination control are crucial, such as pharmaceutical production,
biotechnology, semiconductor manufacturing, and research laboratories. They
contribute to the integrity of the cleanroom or controlled environment by
lowering the number of times doors are opened and hence the possibility of
airborne pollutants entering.