Senior Airman Bradley Biery, 633rd Force Support Squadron patrolmen verifys Airman 1st Class Kyle Dehaan and Jordan Jensen 633rd Security Forces Squadron entry control point guards, M-50 gas mask's serial numbers, during exercise Coronet White in Raptor Town at Langley Air Force Base, Va. April 20. The Operational Readiness Exercise tests Airmen's abilities to perform self-aid buddy care, Mission Oriented Protective Posture procedures as well as responding approriately to Alarm Conditions. (U.S. Air Force photo by Senior Airman John D. Strong II/Released)