Since the 9/11 Commission Act of 2007, the Transportation Security Administration (TSA) must ensure that 100 percent of cargo on all passenger flights in the United States is screened. To assist, the Department of Homeland Security, Science and Technology Directorate (S&T) is characterizing the air cargo environment (cargo, contamination and facilities), assessing new and modified screening systems, and developing new and advanced screening and detection tools and technologies. New technologies must screen more effectively without impacting the efficient flow of air cargo.