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U.S. Army Staff Sgt. Henry Cancinos, assigned to Bravo Troop, 1st Squadron (Airborne), 40th Cavalry Regiment, 4th Brigade Combat Team (Airborne), 25th Infantry Division, U.S. Army Alaska, conducts chemical, biological, radiological and nuclear defense training on Joint Base Elmendorf-Richardson, Alaska, April 13, 2016.
The training culminated with masked Soldiers entering a sealed chamber filled with CS gas (tear gas), then removing their protective gear to promote confidence in their equipment. (U.S. Air Force photo by Justin Connaher). Original public domain image from Flickr
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