647 CES holds chemical, biological, radiological and nuclear defense refresher course
U.S. Air Force Airman 1st Class William Dobyns, 647th Civil Engineer Squadron emergency management journeyman, teaches Airmen how to dismantle their assigned gas masks during a chemical, biological, radiological and nuclear defense course on Joint Base Pearl Harbor-Hickam, Hawaii, August 21, 2025. In emergency management, CBRN specialists perform response operations, warning and reporting to support critical missions, ensuring the safety and security of personnel and equipment. (U.S. Air Force photo by Airman 1st Class Aden Brown)