U.S. Air Force Senior Airman Mason Wyman, 633rd Aerospace Medical Squadron aerospace physiology technician, tests the Reduced Oxygen Breathing Device at Langley Air Force Base, Va., June 25, 2014. The ROBD allows 633rd AMDS personnel to discreetly reduce airflow for more realistic training on hypoxia awareness for pilots. (U.S. Air Force photo by Senior Airman Austin Harvill/Released)