(NC) Being screening-savvy saves you time, as July and August are the busiest time of year at Canadian airports, with more than 10 million passengers expected this summer.

Most air travellers know there are rules about what they can and can’t bring in their carry-on baggage. Some of the rules are obvious — no knives, weapons or explosives — but those around liquids, gels and aerosols can be trickier.

“One of the biggest hold-ups at our security checkpoints is having too many liquids, aerosols and gels,” explains Mathieu Larocque, who works for the Canadian Air Transport Security Authority. “These substances have to be in containers of 100 millilitres or less, placed in a one-litre resealable plastic bag and removed from your carry-on bag for inspection. Larger containers and overstuffed plastic bags won’t fly.”

However, there are some important exceptions. Both prescribed and over-the-counter medications can be in larger quantities, but they should be left in the original manufacturer’s packaging or with pharmaceutical labels intact so they can be easily identified.

Liquids for children under two years old, such as breast milk, baby food, formula and juice, can also be in larger quantities. In all cases, the containers should be taken out of the carry-on bag and ready to present to the screening officer for inspection.

You can check CATSA’s website or mobile app for more information.