Senior Airman Renato Avalos, 380th Expeditionary Operations Support Squadron KC-10 Extender aircrew flight equipment technician, tests the communication function on an oxygen mask June 19, 2019, at Al Dhafra Air Base, United Arab Emirates. During an emergency aircrew will need to breathe clean air and communicate to handle the situation and avoid further complications. (U.S. Air Force photo by Staff Sgt. Chris Thornbury)