Airmen assigned to the 512th Airlift Wing receive a pre-exercise briefing on Chemical, Biological, Radiological, Nuclear survival defense during the Ability to Survive and Operate training event, Oct. 14, 2017 at Dover Air Force Base, Del. The briefing focused on proper procedures to dress in protective garments and M50 gas masks. (U.S. Air Force photo by Senior Airman Damien Taylor)