The invention is an apparatus and method for safely depressurizing milling vials. The invention utilizes a machinist vise in communication with a pneumatic air cylinder mounted in a jig inside glove box enclosure. The invention utilizes a method for safely depressurizing milling vials. The milling vials are placed into the machinist vise inside the enclosure. The ram of the pneumatic air cylinder is placed on top of the milling vial and the pneumatic air cylinder is pressed firmly against the cap of the milling vial. Next, the air inside the enclosure is evacuated of atmosphere after which the pressure is slowly released from the pneumatic air cylinder. During this stage of the method the operator is a safe distance from the enclosure. As pressure is removed from the pneumatic air cylinder the ram is retracted and the cap of milling vial is removed.