Air Force personnel at Hurlburt Field conducted training Thursday based on a simulated chemical weapons attack against a base outside the U.S. Staff Sgt. David Norris said the CBRN– Chemical, Biological, Radiological and Nuclear – training is for airmen and civilians that may be deployed to international locations where chemical weapons could be used against them. The training simulated for airmen what they should do before, during and after a chemical weapons attack.