The Nuclear Regulatory Commission (NRC) is proposing numerous revisions to its controls on byproduct material produced by fusion machines. While the primary focus of the proposed rule is the regulatory framework for domestic licensing of the possession, use, and production of byproduct material associated with fusion machines, the proposed rule also includes changes to the definitions of “byproduct material” and “particle accelerator” in the NRC Export Control Regulations (Part 110).

The proposed rule modifies the definition of “byproduct material” to include any material that has been made radioactive by use of a “fusion machine,” which is defined to be a machine that is capable of: 1) transforming atomic nuclei, through fusion processes, into different elements, isotopes, or other particles; and 2) directly capturing and using the resultant products, including particles, heat, or other electromagnetic radiation.

This expansion of the byproduct material definition is intended to ensure that fusion machines are regulated in the U.S. based on the radioactive materials produced, regardless of which technology is used to irradiate the materials. According to the NRC, this is a “technology-inclusive,” “risk-informed approach,” that is appropriate for rapidly evolving, diverse nuclear fusion technologies (e.g., tokamak, stellarator, z-pinch, field reverse, etc.).

None of the proposed changes would impact export controls on the fusion machines themselves. Today, fusion machines are generally subject to the U.S. Commerce Department’s Export Administration Regulations (EAR), which regulates commercial and dual-use items that are not subject to Part 110 or other, industry-specific export control regimes such as the International Traffic in Arms Regulations (ITAR). For example, particle accelerators are listed on the EAR Commerce Control List and controlled for export to a small handful of countries for regional stability and anti-terrorism reasons.

The NRC confirmed that control by the Commerce Department under the EAR remains appropriate for fusion machines, noting that:

Nuclear-related items that do not require IAEA safeguards are generally controlled by the Department of Commerce (DOC). Since fusion machines do not use or produce nuclear material, they do not require the application of IAEA safeguards. Accordingly, the DOC, rather than the NRC, currently controls the export of fusion machines…

The NRC also notes that this is also consistent with international frameworks and commitments, as the Nuclear Suppliers Group Guidelines (INFCIRC/254/Part 1) explicitly excludes “fusion reactors” from the scope of its export controls. The proposed rule suggests that the NRC could revise its approach if in the future “the United States, in conjunction with the international export control community, as well as the IAEA, determine that fusion machines may warrant additional export controls and safeguards.”

Although the NRC confirmed it was not making changes to its export control rules in proposing its revisions, it nevertheless is requesting comments on whether the NRC should propose export controls for fusion machines. Interested parties have until May 27, 2026, to submit comments. Also, the NRC will host at least one public meeting to answer question on the proposed revisions. The date, time, location, and agenda will be posted at on the NRC’s public meeting website at https://www.nrc.gov/public-involve/public-meetings/index.cfm.

Please reach out to Jahna Hartwig, Tim Cox, or another member of Wilson Sonsini’s National Security and Trade practice with questions regarding this new development.