Master Sgt. Damon Leisure performs a buddy check on Airman Aaron Ellison, both from the 375th Communications Squadron cable and antenna maintenance, during chemical, biological, radiological and nuclear training April 26, 2011, at Scott Air Force Base, Ill. CBRN training teaches Airmen the proper procedures to take while in contact with a contaminated substance. (U.S. Air Force photo/Airman 1st Class Divine Cox)