Bringing Frozen Liquids through Airport Security

Gizmodo reports that UK airport security confiscates frozen liquids:

"He told me that it wasn't allowed so I asked under what grounds, given it is not a liquid. When he said I couldn't take it I asked if he knew that for sure or just assumed. He grabbed his supervisor and the supervisor told me that 'the government does not classify that as a solid'. I decided to leave it at that point. I expect they're probably wrong to take it from me. They'd probably not seen it before, didn't know the rules, and being a bit of an eccentric request, decided to act on the side of caution. They didn't spend the time to look it up."

As it happens, I have a comparable recent experience. Last week, I tried to bring through a small cooler containing, among other things, a bag of ice. I expected to have to dump the ice at the security checkpoint and refill it inside the airport, but the TSA official looked at it and let it through. Turns out that frozen liquids are fine. I confirmed this with TSA officials at two other airports this week.

One of the TSA officials even told me that what he was officially told is that liquid explosives don't freeze.

So there you go. The US policy is more sensible. And anyone landing in the UK from the US will have to go through security before any onward flight, so there's no chance at flouting the UK rules that way.

And while we're on the general subject, I am continually amazed by how lax the liquid rules are here in the US. Yesterday I went through airport security at SFO with an opened 5-ounce bottle of hot sauce in my carry-on. The screener flagged it; it was obvious on the x-ray. Another screener searched my bag, found it and looked at it, and then let me keep it.

And, in general, I never bother taking my liquids out of my suitcase anymore. I don't have to when I am in the PreCheck lane, but no one seems to care in the regular lane either. It is different in the UK.

EDITED TO ADD (10/13): According to a 2009 TSA blog post, frozen ice (not semi-melted) is allowed.

Hannibal Burgess routine about the TSA liquids rules.

Posted on September 22, 2015 at 1:22 PM • 56 Comments


tedderSeptember 22, 2015 1:59 PM

So, TSA collectively failed General Chemistry.

I haven't taken liquids out in years, but I tend to not travel with many- a tiny tube of toothpaste and a thing of deodorant.

DominicSeptember 22, 2015 2:04 PM

Funny, I once had a TSA agent at a small airport tell me if I froze a bottle of water, I would be able to bring it past security, rather than having to empty it and refill it.

I never tried it, didn't seem worth potentially having to pitch my water because someone disagreed.

ChrisSeptember 22, 2015 2:16 PM

Funny. In Albuquerque, New Mexico, you're not allowed to go through security with green chili (liquid? gel?) unless it's frozen. Not sure if it's according to the logic above or a special dispensation from the TSA Pope.

SBSeptember 22, 2015 2:21 PM

Melbourne (Fla) airport once intercepted my wife's bottle of water (and disposed of it in the presumably explosive-proof trash bin at the checkpoint) but had no problem with the now-nearly melted bag of ice that was keeping some food cold.

SSSeptember 22, 2015 2:26 PM

@Chris, Interesting since NMT (EMRTC) is the place that came up with the liquids rule and that is their airport. They know the ABQ TSA well.

NealSeptember 22, 2015 2:27 PM

A few years ago, Denver TSA confiscated my jar of frozen homemade jam that I was bringing to a friend. TSA claimed it was a liquid. (The thing was seriously frozen solid.)

Mike S.September 22, 2015 2:30 PM

The TSA blogged about this when they let Britney Spears through with drink cup.

"Her cup had a few ice chips in it, not liquid. Ice is a solid. Therefore, ice is permitted through the checkpoint, as long as it's screened by the X-ray (Which it was). ... One thing to remember when bringing ice through the checkpoint: it can't be partially melted. It has to be just the ice with no liquid at the bottom."

Josh RubinSeptember 22, 2015 3:15 PM

My wife often walks through security holding things like flowers in a water filled glass jar. TSA agents just chat with her about gardening.

I don't understand. Do they have a way of detecting nice people from the Midwest?

ianfSeptember 22, 2015 3:17 PM

?Why? do we even expect compliance to written rules, consistency and logic from agents of (what's clear to all parties involved) is a mandated, but largely illogical security-theater TSA/equiv. activity? Obviously, the non-priority/ economy-class airline passengers are at gate minders' beck and call, and whimsy is the law-du-jour.

In Helsinki I tried to smuggle aboard a hard-frozen can of cola, which I hoped would stay cold for 3-4 hours… but in the >90 minutes it took to get from the hotel to the gate, the frost on it evaporated & it was declared CONTRABAND on sight. While at Paris Orly, the same guard that confiscated my 125g "pocket sized" factory-sealed can of “Pâté de Canard” (seemingly above 100g limit for conserves), let through a salad container, which, when I started eating it aboard the plane, turned out to have oozed 2 cm worth of watery-oily dressing liquid at the bottom (the most emulsified peppery, stomach-bomb part of it). I hope that guard's family choked on my pâté that night, the snooty French bastards.

Bill StewartSeptember 22, 2015 3:19 PM

Somebody's article about this issue was talking about bringing a can of soda frozen in a block of ice. That would be a legitimate thing for TSA to complain about, because (aside from triggering their "unfamiliar things" reactions) there's no way to know that it's really a can of soda inside the ice, as opposed to a bomb. The ice itself should be fine.

CallMeLateForSupperSeptember 22, 2015 3:32 PM

Here in the Disparate States of Litigation there are many examples of such. A state says no; fed. says yes. Adult beverages sold darn near anywhere ... but not in "dry" counties (and never on a Sunday in Massachusetts!).

A specific example that sticks in my mind is crossing a double, yellow line (road lane separater). Doing that in Indiana (where I took driver education) was illegal, but in New York State it is not illegal.

ianfSeptember 22, 2015 3:43 PM

@ Josh Rubin, your wife's habitual ease of passage through security gates can be explained with

a) the guards not mentally connecting "flowers in a handheld jar" with "liquids BEWARE" - and/or

b) her “still having her looks” (as per self-analysis of/by Alice Trillin)

PetterSeptember 22, 2015 3:52 PM

Dry ice is allowed in both chacked in as well as carry-on, but only in baggage and not carried on one's person.

Carbon dioxide, solid (dry ice), in quantities not exceeding 2.5 kg per person when used to pack perishables not subject to these Regulations in checked or carry-on baggage, provided the baggage (package) permits the release of carbon dioxide gas. Checked baggage must be marked “dry ice” or “carbon dioxide, solid” and with the net weight of dry ice or an indication that there is 2.5 kg or less dry ice.

MikkoSeptember 22, 2015 4:09 PM

In Helsinki Airport the security staff (when they are not on strike) regularly confiscate cheese from hand baggage as they claim "if you heat it up, it will turn into a liquid". They didn't like it when i told them "so will my laptop". Jobsworths.

ZSeptember 22, 2015 4:15 PM

Honestly? As much as I am generally sympathetic to tales of airport security overreach and/or stupidity, this one seems like a waste of outrage.

Assuming for the sake of argument that a ban on liquids is rational and consistently applied, I think it's quite reasonable to read the rules with an implied statement that a "liquid" for those purposes is any substance that is in liquid form at standard temperature and pressure.

Spending time quibbling over nonsense like this is like the boy who cried wolf.

AnuraSeptember 22, 2015 4:24 PM


"I think it's quite reasonable to read the rules with an implied statement that a "liquid" for those purposes is any substance that is in liquid form at standard temperature and pressure."

Which is ambiguous for water. Also, a lot of explosive liquids, nitroglycerin for example, is frozen at STP.

ZSeptember 22, 2015 4:32 PM


OK, fine, say "room temperature" then. The point is, it's not an unreasonable interpretation of what a "liquid" means in context and isn't worth fighting about.

And your point about the physical state of explosives is noted, but irrelevant for these purposes, as I you will see I assumed for the sake of argument that the general prohibition on liquids is rational - which in reality is not a given. If you want to contest that, by all means, but you won't find me arguing the TSA's (or UK Border Agency's) case.

Clive RobinsonSeptember 22, 2015 4:43 PM

@ Gord,

Pretty much everything is a frozen liquid

Agh but some solid liquids are not frozen...

Custard is a good example of a non Newtonian liquid as is 50:50 cornflour and water mix. Aside from Mythbusters, Numb3rs also had a show with people "running on custard". The cornflour mix can give hours of fun for 3-12year olds, and even adults, if you put it in a balloon as a "hard to beat stress ball".

Silly but interesting fact, if you put a raw egg inside a ballon of water and drop it from suficient hight so the balloon breaks then the egg will break as well. However if you fill the same size balloon with the same quantity of custard and put an egg in it and drop it from the same hight, the custard goes solid on impact and neither the balloon or egg break (although the yolk might). Back in the day when we did "practical science" with real experiments it's the fun experiments you remember ( not the boring ones about nitrates and brown rings, though I do rememder lead azide demonstration for some reason ;-).

4posteriteaSeptember 22, 2015 6:53 PM

You have got to start writing EVERYTHING you know down. The loss of knowledge should you pass would be devastating. I consider myself a smart one, but you have so much it never fails to fascinate me, mispellings (that you explained a long time ago) not withstanding.

Clive RobinsonSeptember 22, 2015 8:21 PM

@ John Galt IV,

With regards the TSA agent stealing a few bucks from a wallet, what's a little larceny amongst friends, when you can get your lady friend to game the system so you can grope up an attractive guy's junk,

Whilst people went "I told you this would happen" over the sexual assult, the real point is "gaming the system". Because if a couple of TSA low lifes can game the system to get their perverted jollies for so long, then evade the sexuall offence punishment such behaviour deserves, think how lax the system realy is, thus how easy it's going to be for a terrorist to game the system at will...

Clive RobinsonSeptember 22, 2015 8:37 PM

@ 4posteritea,

You have got to start writing EVERYTHING you know down.

I don't think some people would approve of me doing that, they are kind of sensitive souls ;-)

But just for fun... I mentioned lead azide above, you might know that most azide's are quite poisonous, some more so than cyanide.

One of the more poisonous azides is also used as the "gas generator" in vehicle "air bags"... and you can by such units in "breakers yards" for only a couple of bucks no questions asked... I'm told the LD50 for that azide is a little over half a gram and each unit contains way more than that... I was thinking of saving it for a movie plot.

Clive RobinsonSeptember 22, 2015 9:37 PM

@ Nick P,

Yup that's the water and cornflour mix all right, maybe we should get Bruce to run across one to start another Chuck Norris style slogan ;-)

DaveSeptember 22, 2015 10:39 PM

"liquid explosives don't freeze"

Do you have the contact details for this TSA person? My company has been given an exclusive contract by the city of San Francisco to sell the Golden Gate Bridge, and we'd like to contact him/her with a share offer.

(The most common liquid explosive, nitroglycerin, freezes just fine, in fact it's used to render it safer for shipping since it's less shock-sensitive in the solid than liquid form, except that thawing it is a bitch).

RalphSeptember 22, 2015 10:52 PM

The thing about the liquids rules that has always puzzled me: The limit is based on volume. But as far as I know the volume is assessed by reading the label.

So they are trusting that terrorists will not put an incorrect label on a bottle?

I suspect I am not the first person to have thought of that. Have the rules been designed conservatively with that in mind? How much can you lie about the volume on a label and get away with it?

JphnSeptember 22, 2015 10:59 PM

Bought a 20oz water inside security 30ft from the gate in HKG. At the bend in the jetway, Chinese security took it away.

Then a couple sat next to me with 2 Popeye's dinners and 2 canned sodas. I was pissed.

I've flown all over Asia and liquids generally aren't any issue, but on flights TO the USA, all the security becomes anal ... won't say anything about the groping when leaving Prague for JFK a few years ago - no bottled fluids involved, but my "lemons" were squeezed - multiple times by different security people.

milkshakenSeptember 23, 2015 2:43 AM

so liquid explosives do not freeze?? I though pure nitroglycerin freezes just below room temperature, at +14C (57F) and is typically blended with other nitroesters when used in dynamite or gelignite, just to prevent it from freezing on a cold day (freeze and thaw makes dynamite really unstable)

SHaSeptember 23, 2015 2:49 AM

In some cases, the liquid collection practice itself is a major vulnerability. It is not unusal with crowds with hundreds of people gathered for the security checks. Many of them tossing their bottles with liquides in containers in the midst. These crowds are often much larger than the number of passengers on an average plane.

For security companies, it is probably not good for business do thorough risk assessments. (Of course one could have a security check before the security check)

Clive RobinsonSeptember 23, 2015 3:05 AM

@ Ralph,

How much can you lie about the volume on a label and get away with it?

From what I remember, the nearer a container is to a regular shape like a cube or sphere the worse the guess on volume.

The old "rope around the earth" question gets most adults in the opposite direction more often than not...

ChristianSeptember 23, 2015 7:24 AM

Terrorist plot:

The melting point of Nitroglycerin is above that of water.

If you can bring frozen water it shouldn't be hard to pass with Nitroglycerin in frozen form... just smuggle it frozen between water ice cubes...

WinterSeptember 23, 2015 8:01 AM

Correct me if I am wrong. The X-ray system is designed to catch "nitrogen" based explosives. So, TNT, nitroglycerin etc will be caught.

The liquid scare came about when terrorists started to make Acetone-peroxide which could not be detected with the existing devices. Acetone-peroxide is (can be?) a solid, but it is so devilishly unstable that few people transport and use it as such. The idea that people will make it from peroxide, acetone and sulfuric acid during the flight on the toilet is ridiculous.

Using peroxide, it is also possible to make liquid explosives that do not contain nitrogen. I do not know how. But these are the basis of the liquid scare.

The security man who said that explosives do not freeze might mean these peroxide based explosives.

MarkSeptember 23, 2015 8:36 AM

Well, I live in London and travel quite a bit. Last weekend, I was "randomly" chosen as usual, and they just waived 3 of us men through because they only had female stuff available at the time. Farcical.

My razor blade in my double-edge razor was confiscated (carry-on) on my way back to London for the first time in 10 years. I take it everywhere. The lady wouldn't even let me show her how to take the blade out, and she had no idea what it actually was.

Bruce, we all know that there is nothing sensible about any of this. Please do not vindicate them. Your opinion actually matters.

IfYouWantThingsToGetBetterSeptember 23, 2015 8:41 AM

If you want things to get better, when taking foods that are frequently confiscated - drinks, cheese, jams, etc - mix it with a little Phenolphthalein beforehand. For god's sake don't eat it! Stuffs like hippo laxative.

They won't steal your food again!

Also, you'll notice a big difference when traveling based on whether you're dressed like Larry the Cable Guy or wearing a 3-piece suit. $120 sneakers or $10 dress shoes from Walmart. (Go with the dress shoes.) Dressing up helps tremendously! As does age, looking 30-50 years old vs 18 years old. Look mature.

Spaceman SpiffSeptember 23, 2015 11:02 AM

Heck, none of this security theater shit makes any sense to a rational person. Let's just stop funding our versions of the TSA at billion$ per year, when they do zip, zero, nada to protect us!

rgaffSeptember 23, 2015 1:16 PM

@Spaceman Spiff

It has nothing to do with rationality... it has to do with collecting money and power. and that merely needs claiming some excuse to do so... whether the excuse itself is rational or not.

AnecdoteSeptember 23, 2015 1:56 PM

At the Quebec-Vermont border about 25 years ago around 2 AM, the US officer asks me whether I had any food with me. I answer 2 apples. She asks me: "what color"? Answer: Green. "You're gonna have to leave them here". Me: but can I eat them here? Answer: yes.

And that's how I came to eat apples in the middle of a freezing winter night by a deserted country road, half-asleep and without hunger.

I'm puzzling about the logic of the incident since then.

rgaffSeptember 23, 2015 4:22 PM

@ Anecdote

Reminds me of traveling into California... except they don't ask you what color...

John HardinSeptember 23, 2015 5:50 PM

@Anecdote: That was probably due to the possibility of the apples having moth larvae in the core. There are lots of restrictions on transporting personally-harvested apples in WA state for that reason - to control the spread of fruit pests in orchard country.

...which makes orders of magnitude more sense than anything the TSA does.

AnecdoteSeptember 23, 2015 7:05 PM

Red apples are usually of domestic Canadian origin, and there are plenty of orchards within bug flying distance of the border. Donald Trump don't scare them much.

Green ones are often imported either from the US or South Africa...

She definitely didn't ask me about the origin of the apples.

I doubt they could have been from South Africa, as there were still trade sanctions going back them. Memory fades.

Another hypothesis is that the pesticide Alar was discussed a lot back then.

For bug invasions, I ended up throwing the core in an US garbage can, which must have eventually landed in an ordinary landfill, albeit in subzero temperature.

At least she let me eat them, I feel bad about throwing food away.

Thomas_HSeptember 24, 2015 6:55 AM

Some years ago I was told that a tube of toothpaste was a dangerous substance and I should put it in my suitcase instead. At the time I was tempted to pick up a piece of aluminium sheet as used in aircraft, a piece of rope, and test how long it would take me to use the abrasive capacities of toothpaste to cut through the sheet (videotaping everything, of course).

I am also very tempted to point out to airport security that each human being contains multiple liters of fluids, some of which might count as biological weapons, depending on what you ate, who you slept with, and where you have been...if these security rules were actually based on logic they'd have to ban humans and all other living things from flying.

TatütataSeptember 24, 2015 9:48 AM


Toothpaste contains fluoride...

And for the human danger, you could indeed carry high explosives in your bowels, packed in condoms exactly like drug mules do.

All you need to do is to find a way to hide a detonator somewhere. Shouldn't be too difficult.

A long haul flight, a gulp of laxative just before take-off, and a long meditation in the restroom...

Try to imagine how the training camp for the operatives looks like.

So, what's the solution to counter this threat?

Cameras surveillance in toilets?
48-hour pre-flight quarantine of passengers?
Passenger-free flights?
A general prohibition on baked-beans?

mmhhSeptember 25, 2015 4:47 AM

I've flown many times from Ben Gurion airport in Tel Aviv. Always passed security with a bottle of water (0.5 or 0.75 liters) and then boarded on a plane to EU.
Stupid senseless rules just for the sake of the show.

Wesley ParishSeptember 25, 2015 6:54 AM

Reminds me of an AirNZ domestic flight I took in January 2011. I had my pocket trumpet and a bottle of valve lubricant to keep the trumpet playable.

Yep, they confiscated the valve lubricant. It cost me $8.00, but I don't forget, and in this case I don't forgive. $8.00 at a compound interest of 9% over four years - they owe me, and I own them. They're proving remarkably lax about coughing up.

So I expect they'll not only carry a real bomb on board, they'll also arm it for the pterorist, and wave aside all liabilities.


Robert.WalterSeptember 25, 2015 2:23 PM

They don't have to be too strict any more as the mission was accomplished: erect a nationwide security theatre with the maximum number of new job slots.

ianfSeptember 26, 2015 11:51 AM

@ mmhh
That's because airport security in Israel follows a different set of criteria & rules when assessing passengers, than do their counterparts in Europe & the USA. Much higher stress is put on psychological factors, and long-range ocular surveillance already on approaches to airport car parks etc. Also, because of higher threat levels, their security personnel is better trained and coordinated than elsewhere (which in itself might not be an exportable quality, esp. to the USA, where the TSA etc jobs are treated and reimbursed as menial labor). EU countries do not like to advertise that they cooperate on security with Israel, but they do more and more. It's been ages since I've last been there, my first—thus memorable—butt inspection, but I usually ask returnees for their impressions of security procedures.

Generally speaking, the (incoming) security (lots of) gals there seem to know in advance who is coming, and, if a journalist who's known to have visited/ filed stories from "Israel-a[d]verse" countries, their mobile phones and laptops tend to be confiscated for half an hour. After that they are returned in NO QUESTIONS NO ANSWERS fashion, same condition. Apparently the Israelis have ways to siphon off data of any phone and computer without one's silly passwords, or at least add their IMEI and SIM IDs to a watch list. Only some phones were confiscated, definitely not everybody's in the queue. Passenger was asked to wait, offered water, shown the direction of a toilet (still within the secure area). The Israelis have learned a lot, and won't "allow" another Lod Airport Massacre (1972) "to happen."

Thus the only somewhat sane way to travel to Israel with privacy intact, is to have an innocuously-set up DECOY phone (not one's ordinary temporarily wiped out, then restored from some cloud backup inside the country as were this secure) that won't arouse suspicions even when examined, and with potentially "offensive" telephone numbers etc either memorized, or posted in some surreptitious, obscurely-encoded fashion online, from where they can later be extracted.

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