Department of Homeland Security Federal Laboratory within the DHS Science and Technology Directorate (S&T) and TSL's core mission is to enhance homeland security, including the research, development and validation of solutions to detect and mitigate the threat of improvised explosive devices (IEDs). DHS S&T establishes CRADAs as public-private partnerships designed to expeditiously mature and deploy security technologies and to prepare products to achieve Transportation Security Administration (TSA) certification/qualification. TSA certified products may be used at ports of entry across the U.S., including airports.