Lance Cpl. Steven Greenwood, right, 22nd Marine

Lance Cpl. Steven Greenwood, right, 22nd Marine Expeditionary Unit chemical, biological, radiological and nuclear defense specialist and native of Albany, N.Y., connects his oxygen supply to the suit of Lance Cpl. David Malin, 22nd MEU CBRN specialist and native of Mesquite, Texas, so the Marines can perform an in-suit replacement of Greenwood's oxygen tank during routine training at Marine Corps Base Camp Lejeune, N.C., June 13, 2013. (Marine Corps photo by Sgt. Austin Hazard/Released)