U.S. Air Force Airman 1st Class Zachary Day, 633rd Civil Engineer Squadron emergency manager, communicates via handheld radio during a hazardous material exercise at Langley Air Force Base, Va., Dec. 18, 2013. The scenarios allowed emergency management and law enforcement personnel to work together and improve crisis management skills. (U.S. Air Force photo by Senior Airman Brittany Paerschke-O’Brien/Released)