A U.S. Sailor with Naval Mobile Construction (NMCB) 25 tests air quality with an M256 chemical agent detector kit during a simulated chemical attack during chemical, biological and radiological (CBR) team training at Naval Construction Battalion Center Gulfport, Miss., Feb. 14, 2014. The training provided NMCB-25 with familiarization in CBR detection and decontamination. NMCB-25 was training for a scheduled deployment in support of Operation Enduring Freedom.