Marines from Marines Forces Reserve practice how to properly report a casualty and possible toxic gas during a chemical, biological, radiological and nuclear defense training simulation aboard Naval Air Station Joint Reserve Base New Orleans, Feb. 5, 2015. When they locate a casualty, Marines must report it to the control center and wait for further instructions. The CBRN defense training equips Marines from diverse units, with the proper knowledge and readiness needed to handle a real combat zone situation. (U.S. Marine Corps photo by Lance Cpl. Ian Ferro)