U.S. Air Force Airmen assigned to the 20th Civil Engineer Squadron, are briefed on a simulated hazardous scenario during an integrated base emergency response capability training exercise at Shaw Air Force Base, S.C., Dec. 10, 2014. During the five-day training, Airmen were tested on their emergency response preparedness through a series of simulated chemical and biological attacks. (U.S. Air Force photo by Airman 1st Class Jensen Stidham/Released)