Airmen of the 28th Medical Operation Squadron bioenvironmental engineering flight use a hand-held assay during an integrated base emergency response capabilities training exercise at Camp Lancer at Ellsworth Air Force Base, S.D., July 16, 2015. Airmen used the HHA to identify possible biological agents in unknown chemicals found during the exercise. (U.S. Air Force photo by Senior Airman Rebecca Imwalle/Released)