Mask Mission Marine Corps recruits perform chemical, biological, radiological and nuclear defense training at Marine Corps Recruit Depot Parris Island, S.C. Jan. 10, 2022. The training teaches recruits how to properly use a gas mask. SHARE: Download: Full Size (1.29 MB) Tags: Marine Corps Credit: Marine Corps Lance Cpl. Dakota Dodd VIRIN: 220110-M-PC612-1358M.JPG Photo Gallery