The Transportation Security Administration (TSA) recommends using the 3-1-1 rule for determining if carry-on luggage will pass inspection. The system 3-1-1 means that you have 3.4-ounce (or less) bottles of liquid items in the bag, a 1-quart clear plastic zip-top bag to contain them and only one bag per passenger. Adhering to this rule will prevent security delays due to searched bags at the airport.
Certain liquid items can be larger than 3.4 ounces, but must be declared to a TSA officer during the security screening. Medications, baby formula and food, and breast milk are allowed in reasonable quantities, according to the TSA. They are not required to fit into the 1-quart zip-top bag, but they must be openly presented to TSA personnel.
Some items are not permitted on board the airplane in carry-on luggage, according to the TSA. These items are sharp objects, sporting goods, martial arts equipment, firearms, flammable or explosive chemicals and tools. Also, more commonplace items such as gel shoe inserts, gel-type candles, paint and snow globes are not allowed in carry-on bags. Many of these items are, however, allowed within checked luggage if properly wrapped and packaged, but may need to be declared in some cases.
According to The Travel Insider, checked luggage can weigh up to 50 pounds per bag (as of 2010). Most airlines allow two checked bags per passenger at no charge, with the 50-pound limit applying to each bag. This is a decrease from the previous 70-pound limit. Any luggage or checked items past the two-per-person limit are subject to fees, as determined by the airline.
Before traveling, research the airline's specific policies and fee structure for checked luggage. No standardized requirements are available from TSA for these items.
