Lieutenant Donald Collins was assigned to the University of Chicago's Met Lab in the Health Physics Division. Collins had graduated with a B.S. in physics from Michigan State University in 1942. Upon graduation, Collins joined the Army Air Forces and was assigned to the Mangattan Engineer District, before being transferred to the Met Lab at Chicago.
Collins' final assignment with the Army was as a member of the 14-man Atomic Bomb Investigative Commission that entered Hiroshima and Nagasaki after the war. In Japan, Collins helped determine the radiation exposure doses to the survivors.