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U.S. Department of Energy

HSS Office of Classification

Office of History and Heritage Resources

Declassification of the Number of Devices and Amount of Plutonium in Nuclear Tests

U.S. Department of Energy, Office of the Press Secretary, Washington, DC 20585


Declassification of the Number of Devices and Amount of Plutonium in Nuclear Tests

Table of Contents

Specifically
Background
Benefits
Who Are the Key Stakeholders?
Contact
Attachments
Questions and Answers

The Department of Energy has declassified additional information about the total number of nuclear tests and the number of nuclear explosive devices in each nuclear test. The Department of Energy also has declassified the total quantity of plutonium expended in all U.S. nuclear weapon tests (atmospheric and underground).

Specifically

Background

Benefits

Who Are the Key Stakeholders?

Contact

U.S. Department of Energy
Office of Public Affairs
Contact: Sam Grizzle
(202) 586-5806


Attachments

United States Nuclear Tests with Unannounced Simultaneous Detonations -- By Date
United States Nuclear Tests -- By Date


U.S. Department of Energy, Office of the Press Secretary, Washington, DC 20585


QUESTIONS AND ANSWERS

Q. Why did the United States conduct tests with multiple devices?

A. Mainly to reduce drilling or other construction costs.

Q. Why is a test defined in such a way to include the detonation of multiple devices?

A. The definition of a test was carefully constructed in the Threshold Test Ban Treaty in order to prevent a nation from conducting a test above the 150 kiloton limit and claiming that it was really two or more tests with yields of less than 150 kilotons.

Q. How does information revealed about the U.S. nuclear testing program compare with what is known about other nuclear weapon states testing programs?

A. Because of the Openness Initiative, the public knows far more about the U.S. testing program than that of any other nuclear weapon state testing program. The United States sees no national security threat in revealing this information and encourages other nuclear weapon states to reveal more information on their respective testing efforts.

Q. Why did you revise the total number of U.S. tests to 1,054 which is an increase of three?

A. As part of the review the Department promised in December, we determined that three tests originally considered as part of an announced test with multiple detonations should have been defined as additional tests according to the definition of the Threshold Test Ban Treaty.


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