Who must be screened upon entering an airport?

The requirement for screening all persons other than passengers and their luggage is rooted in comprehensive security protocols aimed at ensuring the safety of all airport operations. This screening policy encompasses a wide range of individuals, including airport employees, vendors, and service personnel, who may not be boarding flights but still have access to restricted areas of the airport.

The rationale behind such extensive screening is to mitigate potential risks posed by any individual who could inadvertently or intentionally compromise security. Airport security measures need to be as robust as possible, given the diverse interactions and activities occurring within airport environments. By implementing screening for all non-passenger individuals, airport security can better secure sensitive areas, monitor for prohibited items, and enhance overall safety measures.

In this context, the other options are narrower in scope and do not align with the security philosophy that emphasizes a holistic approach to safeguarding airports and aircraft. Some options imply limited screening criteria that could leave gaps in security. Therefore, the approach of screening all persons, except for checked baggage, is the most comprehensive and stringent method to maintain safety and security at airports.