LANGLEY AIR FORCE BASE, Va. -- Staff Sgt. Joseph Dunn and Senior Airman Ryan Gross, 633d Civil Engineer Squadron Fire Department firefighters, carry Airman Jessica Howe, 633d Medical Group Dental Squadron technician, away from the scene of a simulated explosion during a Major Accident Response Exercise Feb. 4. MAREs are held on a semi-annual basis to certify and train base emergency responders. (U.S. Air Force photo/Senior Airman Wesley Farnsworth) (RELEASED)