Screening airline passengers, baggage, and cargo is the TSA 's most visible role. There is some overlap between the “prohibited items” the TSA bans from the cabin of the aircraft and the “hazardous materials” that FAA prohibits from baggage.

The TSA (Transportation Security Administration) and the FAA (Federal Aviation Administration) are both under the Department of Transportation, but they have distinct "Safety vs. Security" roles. The FAA is responsible for the safety of flight and infrastructure; they regulate pilot certification, aircraft maintenance, air traffic control, and airport design. If a plane has a mechanical issue or a pilot violates airspace, that is an FAA matter. The TSA, conversely, is responsible for security and the protection of the transportation system from external threats. They manage passenger and baggage screening at checkpoints, air marshals, and the "No Fly List." In short: the FAA ensures the plane is safe to fly and stays in the sky, while the TSA ensures that the people and items getting onto the plane do not pose a threat to the flight. In 2026, they collaborate closely on "Unruly Passenger" protocols, where a TSA security violation can lead to an FAA-issued civil fine.