Practice Time Staff Sgt. Courtney Dunn, an Irwin Army Community Hospital pharmacy technician, rehearses the process of inverting a mock thawed vaccine vial gently 10 times before dilution, according to a manufacturer’s COVID-19 vaccine product. Vials are stored in an ultra-low temperature freezer, thawed, diluted and used within six hours of dilution. SHARE IMAGE: Download Image: Full Size (0.2 MB) Photo By: Tywanna Sparks, Army VIRIN: 201217-A-BW389-1002M.JPG Photo Gallery