A buffer station provides potential improvement for the operation of a facility. By storing to-be-accessed workpieces in the buffer stations of an equipment, the operation of the facility is not interrupted when the equipment is down. The workpieces can be retrieved through emergency access port of the buffer station, thus ensure the continuous supply of workpieces for the workpiece flow of the facility. Algorithm for getting the needed workpieces to the buffer station is also provided through a controller or a computer mechanism. The buffer station can be incorporated in a stocker, such as wafer stocker or reticle stocker.