U.S. Air Force firefighters participate in a chemical, biological, radiological, nuclear and high-yield explosive threat exercise at Langley Air Force Base, Va., March 26, 2015. The exercise tested Joint Base Langley-Eustis personnel’s ability to react and respond to a potential CBRNE threat. (U.S. Air Force photo by Senior Airman Kayla Newman/Released)(Photo was cropped and levels were used to emphasis subject.)