Generally, most airlines have the same size requirements for carry-on baggage and ask that the bag be no larger than 45 linear inches (the total of the height, depth and length of the bag; for example, 20 inches high by 10 inches deep by 15 inches long). Additionally, passengers are limited to one carry-on bag and one personal item such as a purse or laptop. Bringing a bag larger than the maximum size requirements or more bags than allotted may result in the bags being checked for the duration of your flight.
One of the most important things to consider are liquid items in your carry-on. The Transportation Security Administration has strict guidelines for liquids that travelers must adhere to. "3-1-1" is the easiest way to remember the policy for liquids carried on board. No more than 3 oz. of liquid per bottle, placed in a 1 qt. zip lock bag and no more than 1 bag per passenger. Some items are considered exceptions to this rule, such as baby formula, medications and breast milk. Just make sure to declare these items at the checkpoint before sending your bag through the scanner.
Many prohibited items can be left to common sense such as firearms, gunpowder and other explosives, but other items deemed unacceptable for carry-on are not quite as obvious. The following items should be checked in order to avoid confiscation and travel delays due to additional search and screening. Sharp objects such as utility knifes, swords, box cutters, cleavers and axes should be checked at the ticketing counter. Sporting goods such as bats, ski poles, hockey sticks, golf clubs and bow and arrow should be checked as well. Most tools are prohibited like saws, hammers, drills and axes with the exception of screwdrivers, wrenches and pliers less than 7 inches in length. Self-defense items such as night sticks, stun guns, martial art weapons and self-defense sprays are also strictly prohibited as carry-on items. Flammable items and hazardous liquids such as fireworks, bleach, chlorine, fuel, flammable paint and turpentine are not allowed either.
Not only is your carry-on luggage a place to hold your travel documents, camera, medications and items to make your flight more comfortable, it's also a place to keep extra items in the event that there is a delay in getting your checked bag. With that in mind, make sure to pack a comfortable change of clothes. In addition, you should any expensive electronic equipment such as an iPod, laptop or digital camera in your carry-on.
