Breath normally
Staff Sgt. Heidi Williams, 47th Civil Engineer Squadron emergency management technician, looks through her self-contained breathing apparatus at a joint unit response training event on Laughlin Air Force Base, Texas, June 17, 2014. The SCBA is part of the Level A protective equipment that includes a fully-encapsulated chemical-protective suit and positive pressure, chemical-resistant boots . (U.S. Air Force photo/Staff Sgt. Steven R. Doty)(Released)