TEAR GAS TRAINING Marine Sgt. Carlos Iruegas prepares tear gas in the gas chamber on Marine Corps Base Hawaii, March 19, 2015. Gas chamber training is an annual requirement for Marines. Iruegas is a Pacific chemical, biological, radiological and nuclear defense chief assigned to U.S. Marine Corps Forces. SHARE: Download: Full Size (0.06 MB) Credit: VIRIN: 436411-I-WJN69-671.jpg Photo Gallery