Airman 1st Class Jeremy Harrison and Senior Airman Matthew Hung, 28th Civil Engineer Squadron emergency management journeymen, use multi-ray gas detectors during a training exercise at Ellsworth Air Force Base, S.D., Jan. 20, 2012. Emergency management performs monthly exercises based on real-world scenarios to ensure Airmen stay prepared in the event of an actual emergency. (U.S. Air Force photo by Airman 1st Class Kate Thornton/Released)