List of U.S. security clearance terms

The followings list of terms is used to indicate type, level, or scope of security clearance and background investigation in the United States.

Security clearance descriptors often appear in employment advertisements, as employers generally prefer to hire people who are already cleared to access classified information at the level needed for a particular job or contract.

Due to the nature of security classifications and clearances, often people incorrectly identify their clearances by a combination of actual clearance level, additional access controls, caveats, and the organization who granted them clearance. In addition, different organizations within the Federal government use different terminology and lettering, as is discussed below. In general, most employers look for candidates that hold an active DoD collateral clearance or a blanket TS/SCI-cleared individual that has successfully completed a counterintelligence (CI) or full-scope polygraph (FSP).

Some items on are based on a list compiled by a [http://www.abovetopsecret.com/forum/thread40058/pg1 nonauthoritative source] on the Internet. Items marked "*" are defined in the 2006 U.S. Government's "National Industrial Security Program Operating Manual (NISPOM)" p. 14 ff [http://www.dss.mil/files/pdf/nispom2006-5220.pdf] Any combination of the SI, SI-ECI-*, B, G, HCS letters can be used.

U.S. Classified Information is classified at 3 levels. For access to this information, the sponsoring government organization grants collateral clearances at the following levels:

*C - Confidential *
*S - Secret *
*TS - Top Secret (DoE has the Q clearance which is equivalent) *

In addition to collateral access, the government also supports access to sensitive compartmented information (SCI) and special access programs (SAPs) in which access is determined by need-to-know. These accesses may also require increased investigative requirements before access is granted.

Some categories of information, while possibly but not necessarily needing special access control, by their nature may require extra security education, special handling procedures, et cetera. These are known as caveats:

*FOUO - For Official Use Only *
*COMSEC - Communications Security *
*CNWDI - Critical Nuclear Weapon Design Information
*NOFORN - Not Releasable to Foreign Nationals (access restricted to U.S. citizens) *
*WNINTEL - Warning Notice - Intelligence Sources and Methods Involved [http://www.wasc.noaa.gov/wrso/briefings/WNINTEL.pdf]
*CRYPTO - Cryptographic *

Prior to being granted any clearances or accesses, A person is investigated by the Government. Depending on the level of clearance and access the person needs, the Government undertakes one of the following investigations:

*LAC - Local Agency Check
*ENTNAC - Entrance National Agency Check (typically for new military recruits)
*MBI - Minimum Background Investigation (Typically reserved for Public Trust positions and/or when there is a break in federal service)
*NAC - National Agency Check
*NACLC (National Agency Check with Local Agency Check and Credit Check) *
*SSBI - Single Scope Background Investigation *
*SBPR - SSBI Periodic Reinvestigation
*PPR - Phased Periodic Revinestigation
*SBI - Special Background Investigation
*EBI - Extended Background Investigation

Certain accesses require one to undertake one or more polygraphs:

*Polygraph - Counterintelligence Scope (CI, CI Poly)
*Polygraph - Full Scope / Lifestyle (FSP, FS, LS, Lifestyle Poly)

An incomplete list of the more popular and possible sets of security clearances is below:

*Confidential
*Secret (Collateral)
*Top Secret (Collateral)
*DOE - C, L, Q
*FBI (equivalent to TS Collateral)
*NATO Secret
*Position of Public Trust
*Yankee White
*Top Secret/SCI

SCI clearances assume that the subject has been approved for at least Top Secret collateral information. As a baseline, most individuals that have access to SCI are briefed Special Intelligence (SI, also known as COMINT) and TK. Additional common compartments:
*Gamma (G), subcompartment of SI
*HUMINT Control System (HCS), protects human intelligence

In general, employees do not publish the individual compartments that they are cleared. While this information is not classified, specific compartment listings may reveal sensitive information when correlated with an individual's resume. Therefore, it is sufficient to declare that a candidate possesses a TS/SCI clearance with a polygraph.