Airport security is a topic often surrounded by myths and misconceptions. While regulations are generally consistent worldwide, variations exist depending on the country and even the specific airport. For instance, water is allowed through security on domestic flights in Indonesia but not permitted on flights to Australia from Vietnam.
In the United States, anyone unsure about what they can bring on an airplane should consult the Transportation Security Administration (TSA) or relevant authorities in other countries. Airlines also have their own rules; some allow pets onboard while others do not.
Despite federal regulations enforced by the TSA across US airports, security checks may vary due to different interpretations of guidelines and local regulations. For example, having TSA PreCheck does not guarantee a smooth experience as random checks and behavior-based screenings still occur.