Material Control and Accounting


In the early years of the nuclear age all special nuclear material (SNM) was owned by the Federal government. It was a valuable commodity and the Atomic Energy Commission (AEC)—the predecessor of the NRC and the Department of Energy (DOE)—had a financial duty to keep track of the material as it was lent to various scientists and organizations for their use. To accomplish this, procedures for tracking and accounting for the SNM were established. This is similar to how a bank account keeps track of money; whether it was deposited or withdrawn. Unlike money, however, SNM cannot be "counted". The amount of SNM is determined by weight and assay, as with precious metals such as gold and silver.


The government no longer owns all SNM. The DOE, a successor to the AEC, owns SNM and also has SNM on loan to other agencies and companies. The NRC, however, inherited regulatory functions of the AEC and does not own SNM. The majority of the functions of the NRC and DOE are now independent of each other. The NRC now uses modified procedures which have its roots as financial and materials management tools. The NRC's chief objective of the Material Control and Accounting program is to verify that SNM processed by NRC-regulated fuel cycle facilities is intended for peaceful use and has not been stolen or diverted to unauthorized users.

The NRC reports certain incidents to Congress as part of the annual report (NUREG-0090) on abnormal occurrences. Criteria outlines when the NRC must make these notifications. With respect to nuclear safeguards, the criteria includes 1) a substantiated case of actual theft or diversion of a formula quantity of special nuclear material or 2) a substantial breakdown of physical security or material control (i.e., access control containment or accountability systems) that significantly weakened the protection against theft, diversion, or sabotage.

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International Community

In support of its policy of nonproliferation of nuclear weapons and the Non-Proliferation Treaty, the U.S. Government has voluntarily entered into an Agreement with the International Atomic Energy Agency (IAEA) to have a national system of accounting for source and special nuclear materials. This information system is called the Nuclear Materials Management and Safeguards System (NMMSS). NMMSS contains current and historical data on inventories and transactions involving source and special nuclear materials within the U.S. and on all exports and imports of that material. NMMSS is jointly funded by DOE and NRC and is operated under a contract to DOE.

Regarding the reporting requirements to the international community, substantiated losses of nuclear materials within the U.S. are reported to the IAEA's Incident and Trafficking Database as part of international efforts to monitor lost, stolen, and illicit trafficking of nuclear materials worldwide.

Material Control and Accounting

Material control means the use of control and monitoring measures to prevent or detect loss when it occurs or soon afterward.

Material accounting is defined as the use of statistical and accounting measures to maintain knowledge of the quantities of SNM present in each area of a facility. It includes the use of physical inventories and material balances to verify the presence of material or to detect the loss of material after it occurs, in particular, through theft by one or more insiders.

The agency's regulation of Material Control and Accounting programs safeguards the SNM maintained and processed by facilities licensed by the NRC. The NRC has created categories of SNM to ensure that the regulations placed on the material is commensurate with the risk. This program is crucial in the protection of the public and in the security of the Nation.

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