• United Airlines has specific carry-on rules regarding various types of items.plane image by JASON WINTER from Fotolia.com
  
  United Airlines' rules for carry-on are fairly simple and straightforward. These rules clearly address the number and type of items you are permitted to bring on board with you. Knowing the rules in advance and packing your bags accordingly can save time and spare you unnecessary confusion and frustration at the airport.
  
  

Number

• United Airlines limits each passenger to two carry-on items (with certain exceptions): one carry-on bag and one personal item such as a laptop in its case, a briefcase, a handbag or a purse.
  
  

Size

• The combined height, width and length of your carry-on bag must not exceed 45 inches. Additionally, your bag must be no more than 9 inches high, 14 inches wide and 22 inches long.
  
  

Liquids, Gels and Aerosols

• You may carry most liquids, gels and aerosols on a plane, but they must be in containers of 3 oz. or less. All such containers must be placed into one quart- or liter-sized resealable clear plastic bag, which must be sealed before you go through airport security.
  
  

Exceptions

• United Airlines makes certain exceptions to its rules regarding both number of carry-on items and liquids, gels and aerosols. In addition to your one bag and one personal item, you may also bring certain other items on the plane with you. These include reading material, outerwear, mobility devices such as crutches and food or drink that you will consume during the flight. Exceptions to the rules about liquids include items such as breast milk, baby formula, medications and juice (if you are a diabetic), which you can carry on the plane in amounts over 3 oz. and which do not need to fit in your resealable bag. You may never carry certain liquids, gels and aerosols, such as gasoline or paint thinner, on a plane.