U.S. Air Force Senior Airman Michael Quatman, 317th Maintenance Squadron aircraft fuel system journeyman, holds a respirator mask at Dyess Air Force Base, Texas, Dec. 20, 2017. The mask, which supplies Airman with fresh air, is worn as they inspect and repair the fuel cell so they aren’t breathing in any hazardous fumes. (U.S. Air Force photo by Airman 1st Class Kylee Thomas)