Staff Sgt. Ervin Faison (left) and Master Sgt. Jon Dahlmer (right), 633rd Security Forces Squadron personnel, clear buildings after responding to an active shooter exercise at Langley Air Force Base, Va., Nov. 15, 2012. Dahlmer said his first priority during a situation like this is to neutralize the threat, and get anyone who isn’t injured out of the area. (U.S. Air Force photo by Staff Sgt. Katie G. Ward / Released)