"[2] Newly promoted to major, Fassold "was appointed lllBase lllSurgeon at Canadian Forces Base [RCAF] Trenton, Ontario, in 1969 where he served as Flight Surgeon until 1971.
"[4] After returning to Canada in 1973, Fassold was assigned to the surgeon general's staff, in the Directorate of Preventive Medicine in Ottawa, Ontario.
In 1974, he was promoted to lieutenant-colonel, and "after one year as section head…[he] was appointed Acting Director of Preventive Medicine.
"[4] In 1977, Fassold was promoted to colonel and appointed "Commanding Officer of the Canadian Forces Environmental Medicine Establishment and Deputy Chief (later acting Chief) of the Defence and Civil Institute of Environmental Medicine in Toronto",[4] Ontario.
"[6] He also served as Occupational Medicine Consultant on Transport Canada's Aviation Medical Review Board (AMRB) and as Chair of the Canadian Space Agency's Life Sciences Advisory Committee.