The International Atomic Energy Agency (IAEA) applies technical measures referred to as ‘safeguards’ to verify the accuracy and completeness of the declarations provided by countries on their nuclear material and activities. The 1957 Statute of the IAEA provides the fundamental basis for the establishment of safeguards which today have become grounded within the 1970 Treaty on the Non-Proliferation of Nuclear Weapons (NPT), regional Nuclear Weapons Free Zones (NWFZs), and multilateral and bilateral trading guidelines. The IAEA safeguards system has evolved over the decades, from an ‘item-specific’ approach of the 1960s to one that is increasingly ‘integrated’ and ‘state level,’ applying to all nuclear material in country. As this system has evolved, more materials at the front end of the nuclear fuel cycle have become subject to safeguards.
Although the consequences for proliferation of nuclear materials at the very front end of the nuclear fuel cycle – specifically during mining, processing, transport and conversion of uranium – is low given it must be further processed through a series of steps before producing ‘direct use’ material suitable for nuclear weapons, safeguards (alongside materials security) allow for increased detection in providing assurances for peaceful uses. Approximately 10 tU (or 12 tonnes of U3O8) is needed to manufacture a nuclear explosive device while 200 tU3O8 is needed to keep a large (1000 MWe) nuclear power reactor generating electricity for one year. With smaller volumes needed to make a nuclear explosive than to fuel a nuclear power plant, materials need to be tracked, accounted for, and reported. The timeliness goal for detection of the diversion of a ‘significant quantity’ of natural uranium is one year.
The Starting Point of Safeguards
Natural uranium is considered to be source material under the IAEA Statute and thus a type of nuclear material as defined in IAEA document INFCIRC/153 (Corrected) which provides the basis for Comprehensive Safeguards Agreements (CSAs) in connection with the NPT. Paragraphs 33 and 34 fall under the heading ‘Starting Point of Safeguards.’
Paragraph 33 provides that safeguards shall not apply to material in mining or ore processing activities. Reporting begins with paragraphs 34(a) and (b) which require a state to report the quantity and composition of imports and exports of any material containing uranium or thorium that is to be used in the nuclear supply chain (i.e. used in a nuclear reactor) in a non-nuclear-weapon state (NNWS). This means materials traded for nuclear purposes containing even trace quantities of uranium or thorium (such as phosphates, mineral sands, coal and rare earth elements) should be reported. If such material is not destined for nuclear purposes (e.g. for use in ceramics), then it does not need to be reported under INFCIRC/153. States that have an additional protocol to their CSA, also need to report such materials if used for non-nuclear purposes.
Paragraph 34(c) of INFCIRC/153 (Corrected) is commonly referred to as the ‘starting point’ at which material accountancy and control provisions take effect. It states:
When any nuclear material of a composition and purity suitable for fuel fabrication or for being isotopically enriched leaves the plant or the process stage in which it has been produced, or when such nuclear material, or any other nuclear material produced at a later stage in the nuclear fuel cycle, is imported into the State, the nuclear material shall become subject to the other safeguards procedures specified in the Agreement.
Material accountancy and control therefore begins when nuclear material of suitable composition and purity for fuel fabrication or enrichment ‘leaves the plant or process stage,’ and, until 2003, this point had been interpreted as the output of conversion plants, such as Uranium Hexafluoride (UF6) or Uranium Dioxide (UO2). Thus the final product store was subject to full safeguards, but the input store and chemical processing plant were not.
Clarifying Paragraph 34(c)
In 2003 the IAEA reviewed the technical basis for its previous interpretation of paragraph 34(c) of INFCIRC/153 for the first time with the introduction of ‘Policy Paper 18.’ The paper clarified that the production of purified uranyl nitrate (or the first practical point earlier) met the criteria of paragraph 34(c). Uranyl nitrate (H2N2O8U) is the compound produced by dissolving UOC in nitric acid (and then usually purified by solvent extraction) for the subsequent manufacture into either UF6 (for feed to an enrichment plant) or direct conversion to uranium oxide (suitable for fuel fabrication). Policy Paper 18 also captured oxides such as purified uranium trioxide (UO3) in conversion facilities. The clarification affected a handful of non-nuclear-weapon states, specifically those that have a comprehensive safeguards agreement and refining or conversion facilities.
In 2013, the IAEA issued another clarification. Policy Paper 21 further clarified that any uranium ore concentrates meeting the purity specifications for nuclear-grade, sinterable UO2 fuel (as per the standard specification of ASTM-C 753-04) is subject to paragraph 34(c). Replacing Policy Paper 18, the 2013 clarification captured more materials in more countries, covering not only refining/conversion activities, but also the production of a high purity UOC and “any other nuclear material of a composition and purity suitable for fuel fabrication or for being isotopically enriched.” This allows for the possibility that materials not listed may constitute the starting point.
The Additional Protocol
In 1997, the IAEA passed the Model Additional Protocol (INFCIRC/540), an addition to CSAs which grants broader information on (and IAEA access to) domestic uranium production, as well as data on trade in secondary materials that may contain uranium or thorium. Articles 2(a)(v) and (vi) of an additional protocol (AP) require annual reporting of uranium and thorium holdings (location, number of operational mines, purity, and production capacity for the year prior and potential for the year ahead), along with reporting on exports and imports of “pre-34(c)” source material for non-nuclear purposes. Articles 4 and 5 spell out the IAEA’s ‘complementary access’ to verify the absence of undeclared nuclear material.
For those without comprehensive safeguards agreements (or the additional protocol), there are no legal obligations to track secondary uranium sources. Only for countries with both comprehensive safeguards agreements based on INFCIRC/153 and APs in force can the IAEA draw a broader conclusion on whether all nuclear material in country is used solely in peaceful activities. For those with CSAs but no AP, the Agency draws the conclusion that declared nuclear material remains in peaceful activities.
As of 1 May 2018, 132 states (including Euratom) had the Additional Protocol in force. The IAEA maintains an updated status report:
The diagram below provides a flow chart of the process from mining and milling to conversion, outlining sections captured by safeguards as they have evolved and been clarified.

Starting Point for Nuclear Materials Security
The governance of nuclear materials security is governed by three international instruments: the 1987 Convention on the Physical Protection of Nuclear Material (CPPNM) and its 2005 Amendment, the 2007 International Convention on the Suppression of Acts of Nuclear Terrorism (ICSANT), and UN Security Council Resolution 1540 of 2004. The IAEA also develops and publishes a Nuclear Security Series to assist member states in implementing a physical protection regime consistent with the obligations and commitments of the three treaties. The guidance is voluntary for member states to implement. Since 1972, the Agency has circulated the document Recommendations for the Physical Protection of Nuclear Material. In 2011, the most recent revision was published as ‘Nuclear Security Recommendations on Physical Protection of Nuclear Material and Nuclear Facilities’ NSS13 (INFCIRC/225/Rev.5).
The provisions in all these instruments apply to UOC. ICSANT’s definition of nuclear material includes ‘uranium containing the mixture of isotopes as occurring in nature other than in the form of ore or ore residue’ which could be used for developing nuclear weapons, while UN Security Council Resolution 1540 binds all UN member states to implement ‘appropriate’ and ‘effective’ accountancy and physical protection measures over ‘materials […] covered by the relevant multilateral treaties and arrangements, or included on national control lists’. The CPPNM and INCIRC/225 state that natural uranium should be protected in accordance with ‘prudent management practice.’
Unlike the timeliness goal for safeguards detecting the diversion of a ‘significant quantity’ of high purity UOC (containing 10 tonnes of uranium), the goal in nuclear security is to detect the unauthorized removal of any UOC equivalent to a single drum over a one-month period. Consequently, inventory measures for nuclear materials security begin earlier in the nuclear supply chain than for international safeguards.
In 2016, the IAEA issued a guidance on “Nuclear Security in the Uranium Extraction Industry,” identifying practical and implementable nuclear security measures that are considered prudent in the production, storage and transport of UOC. The document underscores that security measures based on risk assessments and a graded approach should begin when uranium is being or has been concentrated, purified and transported.
All information for this project comes from reports and research conducted by the Governing Uranium program at the Danish Institute for International Studies and the Stimson Center’s ‘Moving the Starting Point’ project, both funded by the John D. and Catherine T. MacArthur Foundation. Learn more at the DIIS archived website at and the Stimson Center: