Yes, you can actually bring (frozen) drinks through airport security.

Large liquids are one of the items that tourists carry. often forget to remove from your belongings before going through U.S. airport security — the Transportation Security Administration’s 3-1-1 liquids rule prohibits passengers from carrying liquids, specifically gels, aerosols, and spreads, weighing more than 3.4 ounces.

Of course, you can bring an empty water bottle to the airport to fill up at the fountain after you go through security, but if you want to bring a drink from home to enjoy on the plane, there’s still another solution.

According to TSA regulationsTravelers may bring frozen liquids through security, especially those that “will freeze when presented for inspection.”

Items that are “partially melted, mushy, or have liquid at the bottom of the container” must meet the 3-1-1 liquid standard requirements.

One exception to this rule is breast milk, which is allowed in carry-on luggage in quantities greater than 3.4 ounces. This can be helpful for nursing mothers, as the TSA allows milk, formula, and breast milk is pumped out through security without any restrictions placed on them as they are considered “medically necessary liquids”.

According to TSA“Formula, breast milk, infant beverages, and infant/toddler food (including pureed food pouches) in quantities greater than 3.4 ounces or 100 ml are permitted in carry-on baggage and do not need to fit in a one-quart sized bag. This also applies to breast milk and formula cooling accessories, such as ice packs, freezer bags, and gel packs (regardless of whether or not breast milk is contained). Your child or infant does not need to be present or traveling with you to carry breast milk, formula, and/or related items.”

As for how much luggage you can bring, TSA specifies a “reasonable amount.” Summer hullcontent director at TPG, notes that this leaves some discretion up to individual officers.

In her experience, there’s an unwritten limit when your child turns 2 or 3. At that point, TSA tends to stop allowing families to carry other liquids through security, even if it’s a drink for a child in your group. To avoid having any liquids for your child thrown away, she suggests freezing them as an alternative.

“While TSA regulations allow frozen liquids to pass through security, and I can assure you that this usually works in practice, some TSA agents simply interpret things differently than most, so be prepared to read the regulations if you don’t want to throw away your drinks,” she says. “I wouldn’t either.” [bring] dozens of different frozen drinks unless you want to be subject to secondary inspection.”

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