The combined total of the length, width and height of the carry-on bag cannot exceed 45 inches, with standard dimension sizes of 22 by 14 by 9 inches. Bags of unusual shapes may not be allowed as a carry-on item, depending upon the airline or the flight attendant's judgment. The average maximum weight is 40 pounds.
According to the U.S. Department of Homeland Security, passengers are allowed one quart-size, clear, plastic, zip-top bag, which will contain liquid products in bottles no bigger than 3.4 ounces, or 100 ml. The plastic bag is then carried in the carry-on luggage. The restriction of liquid items to one quart-size container should be sufficient for short trips, but if larger quantities of liquid products need to be transported, they should be put in checked baggage.
The standard airline policy allows each passenger to carry on one personal item. According to airlines like US Airways or Continental, these items can include but are not limited to a briefcase, camera, handbag or purse, laptop (in carry bag), reading material or a small backpack.
