Here's the 411 on the TSA's 3-1-1 liquids rule

Editor’s note: This is a recurring post, regularly updated with new information.

We've all been there. Waiting in the Transportation Security Administration line only to hear agents call for a "bag check," often because a traveler had a liquid product in their carry-on that's over the allowed limit (or some sort of other prohibited item).

It's a process that can sure slow things down, particularly on the busiest travel days. As you pack for your trip and consider what to put in your carry-on or checked luggage, it's important to consider what the TSA's limits are for liquids and similar products.

Since September 2006, the TSA has gone by the 3-1-1 rule when it comes to those types of products, including items like toothpaste, shampoo, conditioner, mouthwash and lotion -- sunscreen included.

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In short, the 3-1-1 rule is: Each liquid you bring through the TSA checkpoint must be in a 3.4-ounce or smaller container ("3"), all containers must be placed inside one clear quart-size plastic bag ("1") and each passenger is only allowed one plastic bag ("1").

If you meet those requirements, you should get through security without issue. However, if your liquid items are larger than 3.4 ounces each, you'll have to leave them in your checked bag.

There are a few exceptions, though.

The TSA has kept in place a temporary pandemic exception to the rule, allowing up to 12 ounces of liquid hand sanitizer in carry-on baggage.

Part of this exception: The hand sanitizer will have to be screened separately since it's technically over the limit. You'll need to remove it from your bag before it goes through the scanner.

There are also exceptions for larger amounts of medically necessary liquids, gels and aerosols. You can bring those products in larger, "reasonable" quantities, the TSA's website says. However, you must declare those items to security officers at the checkpoint for inspection.

This could, obviously, take a little more time than if you're traveling without those items.

This exception doesn't include sunscreen, despite calls to relax sunscreen restrictions at TSA checkpoints. Like other liquid products, sunscreen bottles over 3.4 ounces must go in your checked luggage.

There are also many liquids you cannot bring with you.

You can bring creamy cheeses, liquid chocolate, liquid coffee, creamy dips and spreads, gravy, honey, hummus, ice cream, jam, jelly, juice, syrup, peanut butter, salad dressing, sauce, salsa, soda, soup and yogurt as long as they are in a container of less than 3.4 ounces according to the TSA.

Related: Should you get TSA PreCheck or Clear — or both?

And yes, you can bring your water bottle with you, even if it weighs more than 3.4 ounces — as long as it’s empty. This can also be a great way to save money at the airport, since -- as the TSA points out -- many airports have filling stations for reusable water bottles.

When in doubt, consult the TSA’s list of what you can carry through the airport and check with your airline.

Additional reporting by Clint Henderson and Sean Cudahy.