Figure 4: Airports Participating in or Recently Approved for Participation in the Screening Partnership Program (SPP)
This image is excerpted from a U.S. GAO report:
www.gao.gov/products/GAO-13-208
Screening Partnership Program :TSA Should Issue More Guidance to Airports and Monitor private versus Federal Screener Performance
Note: TSA classifies commercial airports in the United States into one of five security risk categories (X, I, II, III, and IV) based on various factors, such as the total number of takeoffs and landings annually, and other special security considerations. In general, category X airports have the largest number of passenger boardings, and category IV airports have the smallest.
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