Sensitive Security Information

Sensitive Security Information or SSI is a term used in the United States to denote sensitive but unclassified information obtained or developed in the conduct of security activities, the public disclosure of which would constitute an unwarranted invasion of privacy, reveal trade secrets or privileged or confidential information, or be detrimental to the security of transportation. It is not a form of classification under Executive Order 12958 as amended. SSI is not classified national security information in the sense of Top Secret, Secret or Confidential. The safeguarding and sharing of SSI is governed by Title 49 Code of Federal Regulations (CFR) parts 15 and 1520. This designation is assigned to information to limit the exposure of the information to only those individuals that “need to know” in order to participate in or oversee the protection of the nation’s transportation system. Those with a need to know can include persons outside of TSA, such as airport operators, aircraft operators, railroad carriers, rail hazardous materials shippers and receivers, vessel and maritime port owners and operators, foreign vessel owners, and other persons.

Information designated as SSI cannot be shared with the general public, and it is exempt from disclosure under the Freedom of Information Act (FOIA).

Following the September 11, 2001 terrorist attacks in the United States, Congress passed the Aviation and Transportation Security Act (Pub. L. No. 107-71) known as ATSA, which established the DOT Transportation Security Administration (TSA). The Act also transferred the responsibility for civil aviation security from FAA to TSA. On February 22, 2002, FAA and TSA published a joint final rule transferring the bulk of FAA's aviation security rules, including FAA's SSI regulation to TSA as 49 CFR Part 1520. It also specified in more detail which information is SSI, and protected vulnerability assessments for all modes of transportation. The Homeland Security Act of 2002 (Pub. L. No. 107-296) established the Department of Homeland Security (DHS) and transferred TSA from DOT to DHS. The Act also amended Title 49 U.S.C. §40119 to retain SSI authority for the Secretary of Transportation, and added subsection (s) to 49 U.S.C. § 114, reaffirming TSA’s authority under DHS to prescribe SSI regulations. TSA and DOT expanded the SSI regulation to incorporate maritime security measures implemented by U.S. Coast Guard regulations and clarify preexisting SSI provisions in an interim final rule (IFR) issued on May 18, 2004. The DOT SSI regulation is at 49 CFR Part 15, and the TSA SSI regulation remains at 49 CFR Part 1520.

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