24 months without reinvestigation, after which an update investigation is required. A Periodic Reinvestigation is typically required every five years for Top Secret and ten years for Secret/Confidential, depending upon the agency. Access to a compartment of information lasts only as long as the person's need to have access to a given category of information. Unclassified (U) is a valid security description, especially when indicating unclassified information within a document classified at a higher level. For example, the title of a Secret report is often unclassified, and must be marked as such. Material that is classified as Unclassified // For Official Use Only (U//FOUO) is considered between Unclassified and Confidential and may deal with employee data. For access to information at a given classification level, individuals must have been granted access by the sponsoring government organization at that or a higher classification level, and have a need to know the information. The government also supports access to SCI and SAPs in which access is determined by need-to-know. These accesses require increased investigative requirements before access is granted. Investigations The following investigations are used in clearance determinations: ANACI (Access National Agency Check with Inquiries) – Initial Confidential, Secret, L, LX; only used for civilian employees NACLC (National Agency Check with Law and Credit) – Initial Confidential, Secret, L, LX; reinvestigations MBI – (Moderate Risk Background Investigation) – NACLC plus a Personal Subject Interview (PRSI) and written inquiries to employers, schools, and references for past 5 years. SSBI (Single Scope Background Investigation) – Initial Top Secret, SCI, Q, QX SSBI-PR – SSBI Periodic Reinvestigation PPR – Phased Periodic Reinvestigation PRS – Periodic Reinvestigation-Secret T3 or T3R - Tier 3 or Tier 3 Reinvestigation, now replace all NACLC. T5 and T5R - Tier 5 or Tier 5 Reinvestigation, now replace SSBI and SBPR respectively. Yankee White – An investigation required for personnel working with the President and Vice President of the United States. Obtaining such clearance requires, in part, an SSBI. Many other investigative products have been used to grant clearances in the past. While some of them are still used to determine suitability for employment or enlistment, only the above are used to grant clearances. Additional investigation or adjudication Certain accesses require persons to undertake one or more polygraph tests: Counterintelligence Scope (CI, CI Poly) Full Scope / Lifestyle (FSP, FS, LS, Lifestyle Poly) SCI eligibility Sensitive compartmented information (SCI) is a