Atomic Energy Act of 1946


Atomic Energy Act of 1946

President Harry S. Truman signs the Atomic Energy Act of 1946. Source: DOE Office of History and Heritage.


Following World War II, government control of nuclear materials was widely debated. The Atomic Energy Act of 1946 determined how the federal government would control and manage the nuclear technology that it had developed with Britain and Canada. The Atomic Energy Commission (AEC) was established under the Act to control nuclear weapon development and nuclear power management.

The Act was sponsored by Senator Brien McMahon of Connecticut who chaired the U.S. Senate Special Committee on Atomic Energy. The Act passed the Senate unanimously and the House by a 265-79 vote. It was signed by President Truman on August 1, 1946 and went into effect on January 1, 1947. It took over operations previously conducted under the Manhattan Project.

Euphoria over the prospects of nuclear power generation led to pressure from private industry to loosen the strict governmental monopoly. The Atomic Energy Act of 1954 amended the Act to give the AEC greater latitude to promote and regulate nuclear power. The beginning success in the nuclear power industry led the United Nations to establish the International Atomic Energy Commission (IAEC) in 1957 to promote the safe use of nuclear power and to monitor the production and use of nuclear weapons around the world.

Glenn Seaborg, who had worked on the Manhattan Project and shared the Nobel Prize in Chemistry in 1951, became chairman of the AEC in 1961. Under his administration, the AEC accelerated the commercialization of nuclear power, but concerns continued to grow about AECs dual role as promoter and regulator of the nuclear power industry.

Additional amendments to the Act were passed in 1959 and 1964. And after being established to address growing environmental concern in the country in 1970, the AECs authority to issue generally applicable radiation standards was transferred to the Environmental Protection Agency.

However, criticism of the AECs priorities continued to mount and finally in 1974, Congress abolished the AEC under the Energy Reorganization Act of 1974. Its regulatory duties were passed to the Nuclear Regulatory Commission and its other tasks were given to the Energy Research and Development Administration. In 1977, under the Department of Energy Organization Act, the Energy Research and Development Administration was disbanded, and the Department of Energy we know today was created.

Documents / Links

Atomic Energy Acts

The History of the Atomic Energy Commission

The Manhattan Project