Airlines differ in their hand luggage allowance. You will want to check with each airline carrier specifically regarding their carry-on luggage requirements. At some airports carry-on luggage may be more restricted than others. However, there are certain rules that apply to all hand luggage regardless of the airline carrier.
Size and weight
Passengers are allowed one piece of hand luggage as well as a handbag or laptop case. Infants are allowed one bag for necessary items they may require during flight. The main piece of hand baggage can be up to the dimensions of 56 by 45 by 25 cm (22 by 18 by 10 inches). These measurements include the wheels, pockets and handle. The bag must fit into the bag gauge available at check-in. An easy way to calculate if your hand luggage is acceptable is to make sure its summed dimensions are 115 cm (45 inches), or less. Hand luggage should be less than 7 kg (15 pounds). The laptop or handbag can be up to 45 by 36 by 20 cm (18 by 14 by 8 inches) and it must fit under the seat in front of you.
You can not bring certain items in your carry-on hand luggage. Sharp objects like box cutters, scissors or knives are prohibited. Sporting equipment that includes sticks or bats that can be used as weapons are not allowed. Guns or gun accessories are not permitted in hand luggage. Hammers and crowbars or other tools must be stowed in check in bags. Martial arts and self-defence items, flammable or explosive items, gel candles and chemicals are not allowed. Check the governing authority website for a comprehensive list of what it not allowed on-board.
Liquids and Gels
Since September 11's terrorist attack, strict international and domestic liquid and gel requirements are mandated. You may carry one quart-sized, zip-top, clear, plastic bag with liquid and gel containers. Each container must be 96 grammes (3.4 ounces) or 100 millilitres or less. When you pass through security, take out the liquid and gel bag and put it on the security screening belt separately from you hand luggage. If you have necessary medications, baby formula and food, and breast milk that is greater than the allowed quantity, declare these items for inspection at the security checkpoint. These items do not need to be in a plastic, quart-sized bag.