Col. Eric J. Steidl, 22nd Marine Expeditionary Unit

Col. Eric J. Steidl, 22nd Marine Expeditionary Unit commanding officer, and Denver native, breaks the seal of his newly issued M-50 field protective mask to allow chlorobenzalmalononitrile gas, a riot control agent, to enter during the MEU's annual gas-chamber training aboard Camp Lejeune, N.C., Aug. 27, 2010. After the seal of the gas mask breaks, the Marine will properly clear the mask of harmful air. The MEU was the first major subordinate command in the Marine Corps on the east coast to receive the new M-50 gas mask for training. The training is designed to instill confidence in the mask and ensure the Marines know the proper wear of the equipment.