Pass through systems protect critical environments while allowing contact with the outside. Essentially a portal between the clean and not clean environments, pass through systems have an interlock that permits only one door to be opened at time.

There are a variety of options that affect overall design, based on the needs of the specific clean room. These needs center around the type of materials or objects entering the pass through. The following are the basic considerations and options:

Overall construction of walls is Formica laminate over particle board. The interior walls, however, may be made of laminate, stainless steel, aluminum, or polypropylene.

The interlock is a concealed latch that prevents both doors from opening at the same time. It may be may be mechanical or electric.

The doors are clear polished Plexiglas in a frame with stainless steel hinges. Safety glass may be used where desirable.

Other options include lighting, shelving, and a "talk through".