Mask Prep An Air Force medical provider participates in an N95 mask fit test at a hospital in Lodi, Calif., Dec. 29, 2020, as Defense Department teams prepare to integrate into California hospitals to provide medical support alongside hospital personnel in response to the COVID-19 pandemic. SHARE: Download: Full Size (1.81 MB) Tags: air force, humanitarian, coronavirus Credit: Army Spc. DeAndre Pierce VIRIN: 201229-A-DJ607-1045Y.JPG Photo Gallery