O, Canada! Packing your liquids for any flight is a bit of a head-scratcher, as anyone who's spent time debating whether deodorant counts as a gel can attest. But when you're trying to bring the world's best maple syrup home, you can't risk having it tossed in the trash by a security agent. Before flying on Air Canada, the country's largest airline, check out the liquids restrictions laid out by Canada's version of the TSA.

Air Canada vs. CATSA: Is There a Difference?

Like in the United States, air travel in Canada is heavily regulated. The Canadian Air Transport Security Authority, or CATSA, is the Canadian equivalent of the Transportation Security Administration. And like the TSA, CATSA creates and enforces rules about what passengers can bring onto planes. Each airline has its own particular guidelines about what it will and won't allow on its flights, but CATSA agents are the ones who inspect travelers' passports and luggage at the security checkpoints in Canadian airports.

What that means is that both Air Canada and CATSA can make you throw away certain items before boarding, but it's CATSA agents that actually inspect your carry-on bags.

Packing Liquids for an Air Canada Flight

So what are those liquid regulations for baggage? If you've flown within the United States since 9/11, you're already familiar with them. CATSA and the TSA have basically the same policies regarding liquids, gels and aerosols.

As an Air Canada passenger, you're allowed to pack a limited amount of liquids, non-solid food and personal items in your carry-on bag. Each container must be no larger than 3.4 ounces, or 100 milliliters, and all the containers must fit into a single 1-liter clear, resealable plastic bag. Each passenger can pack one of these bags in her carry-on luggage.

Familiarize yourself with CATSA's list of all the things that fall into this category. In addition to drinks and other liquids, gels and aerosols, the list of restricted substances includes peanut butter, toothpaste, maple syrup and mascara. That doesn't mean you can't bring a full-sized tube of toothpaste on your trip or buy a large bottle of maple syrup to take home. You just can't pack them in your carry-on.

CATSA and Air Canada allow passengers to pack larger containers of approved liquids, gels and aerosols in their checked bags, but checked liquids are still subject to some rules. Air Canada allows each passenger to pack no more than 2 liters, total, of liquids and similar substances in checked bags. CAFTA's rules also state that aerosol containers in checked bags may be no larger than 500 milliliters, and alcohol is only allowed if it's 140 proof or less.

Exceptions to the Liquid Rules 

Like the TSA, CATSA makes exceptions for travelers with young children or medical conditions. If you're traveling with a child under the age of 24 months, carry on as much breast milk, formula, juice and/or water as your child needs. You're allowed to have more than 3.4 ounces of breast milk in your carry-on bag, even if you're not traveling with your child. Diabetic travelers may have bottles of juice or water if they're medically necessary. Passengers are also permitted to carry liquid or gel medications and distilled water for CPAP machines. Gel and ice packs are usually subject to the same restrictions as other liquids and gels, but CATSA and Air Canada make exceptions for them if they're necessary to cool breast milk or medications that require refrigeration.

You don't have to show any documentation in support of your medically necessary liquids, but do alert a CATSA agent that you have breast milk, gel packs or any other items that fall under this exception. They need to be screened along with the rest of your carry-on items.