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Nuclear Safeguards Education Portal

Introduction to Nuclear Security

September 11, 2001 – A plane heads toward World Trade Center South Tower shortly after the North Tower was hit by another plane.
September 11, 2001 – A plane heads toward World Trade Center South Tower shortly after the North Tower was hit by another plane. 

As a review from the introductory section, nuclear security is the prevention and detection of, and response to, theftsabotage, unauthorized access, illegal transfer or other malicious acts involving nuclear or other radioactive substances or their associated facilities.

The first U.S. regulations for nuclear security were implemented in 1965 following the disappearance of a notable quantity of highly enriched uranium (HEU). Nixon strengthened these regulations for physical protection during his administration, after a string of terrorist attacks throughout the 1970s prompted a fear that a terrorist could acquire nuclear materials. 

It wasn't until the September 11, 2001 attacks on the World Trade Center that the conversation shifted its focus to nuclear security. The 9/11 attacks brought attention to global terrorist organizations and their desire to carry out indiscriminate killings, and the possibility that these organizations might be capable of stealing weapons or radiological materials, or even committing sabotage on a nuclear facility for the purpose of a radioactive release.

Below are some important terms to understand when developing a nuclear security system:

Nuclear Security Regime: includes a range of elements and activities, including: legislation and regulation; intelligence gathering; assessment of the threat to radioactive material and associated locations and facilities; administrative systems; various technical hardware systems; response capabilities and mitigation activities. No single government or industry organization or subsection of such an organization can address these elements in isolation  (Source: IAEA Nuclear Security Series, No.7). 

Physical Protection System (PPS): A Physical Protection System (PPS) integrates people, procedures and equipment for the protection of assets and/or facilities against theft, sabotage, and other malevolent human acts. It can be applied to either facilities or transportation vehicles.

Design Basis Threat (DBT): The attributes and characteristics of potential insider and/or external adversaries, who might attempt unauthorized removal of nuclear material or sabotage, against which a physical protection system is designed and evaluated.

Defense in Depth:  The combination of multiple layers of systems and measures that have to be overcome or circumvented before nuclear security is compromised.

You can click on the above terms for more detailed definitions.


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