Safeguards Information (SGI) is a special category of sensitive unclassified information authorized by Section 147 of the Atomic Energy Act of 1954, as amended. SGI concerns the physical protection of operating power reactors, spent fuel shipments, strategic special nuclear material, or other radioactive material.
While SGI is considered sensitive unclassified information, its handling and protection more closely resemble the handling of classified information than other sensitive unclassified information. The categories of individuals who are permitted access to SGI and the access requirements are listed in 10 C.F.R. 73.21 (full-text).