An Airman with the 188th Fighter Wing takes a drink from his canteen through a gas mask during an ability to survive and operate (ATSO) exercise. Members of the 188th Mission Support Group participated in ATSO training at Ebbing Air National Guard Base, Fort Smith, Ark. ATSO training prepares Airmen for situations they may encounter during chemical attacks. (U.S. Air National Guard photo by Airman 1st Class Cody Martin/188th Fighter Wing Public Affairs)