The Transportation Security Administration (TSA) checks carry-on luggage at airports to prevent explosives or other harmful elements from entering airplanes. This is part of the organization's mission to protect the transportation systems of the United States to ensure freedom of movement for people and commerce.
As carry-on luggage can be accessed throughout a flight, the TSA must ensure that contents of these bags are not going to harm travelers.
There are only a few basic things to always avoid with regards to packing carry-on luggage. While there are the obvious items that individuals should never pack, such as illegal drugs or explosive devices, other prohibited items may not be so obvious.
Liquids and gels must be in individual containers of 3.4 ounces (100 milliliters) or less and placed inside a clear, quart-size, plastic, zip-top bag. The TSA emphasizes that containers should fit comfortably into the bag, and that only one bag is permitted per passenger. If a passenger needs to bring more than 3.4 ounces of any liquid or gel substance, it should go into the checked luggage or be shipped ahead. Prescription medications, baby formula and baby milk are all exempt from this regulation and are subject to inspection by hand at the security checkpoint.