pass box

A pass box, which is also called a transfer hatch or SAS pass (sterile access system), works as a barrier between areas with different levels of cleanliness when materials do have to be moved. The equipment is used to transfer material from an area of lower cleanliness to an area of higher cleanliness, and vice versa.Pass box is one of the cleanroom systems, which is used to transfer materials from one side to other side through controlled environment in order to avoid airborne cross contamination.