Abstract: A clean room ceiling filter system has a filter unit received by a filter unit receiving unit, the filter unit and filter receiving unit define cooperating latch and keeper structure that deflects into fastened engagement and releases from within the clean room by simultaneous pivoting of each latch member of each set of latch members. A tubular rod within the filter unit allows dispensing test material onto the filter media from within the clean room and adjustment of an air flow damper also from within the clean room.