# Airline fluid restrictions: do they serve any purpose? **URL:** \ **Category:** Factual Questions\ **Created:** [January 5, 2015, 4:14am UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008 "2015-01-05T04:14:05Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![coremelt](https://avatars.discourse-cdn.com/v4/letter/c/4491bb/32.png) [@coremelt](https://boards.straightdope.com/u/coremelt)\ **Post date:** [January 5, 2015, 4:14am UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/1 "2015-01-05T04:14:05Z")
Do the bans on fluids more than 100 ml serve any actual security purpose? Can anyone actually justify why they still continue this practise? As far as I can tell the threat from mixing liquid explosives was always exaggerated, in that its both hard to do without attracting attention, involves chemicals that are either very hard to get or would give off obvious odors or other signs and even then would not produce an explosion big enough to actually take down the plane. At most you’d blow a small hole in the fuselage causing an emergency descent or more likely you would simply kill one or two people who were sitting right next to the device. I guess we are entering IMHO or GD territory but does anyone think the restrictions will ever be lifted? (GD Rant: Why do we spend so many billions and cause so much inconvenience on preventing wildly unlikely attacks on airliners, when spending a 10th as much on road safety or public transport improvements would save so many more lives? ) ---
**Author:** ![Duckster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/duckster/32/1244_2.png) [@Duckster](https://boards.straightdope.com/u/Duckster)\ **Post date:** [January 5, 2015, 5:06am UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/2 "2015-01-05T05:06:48Z")
Why the restriction was imposed was the perceived threat back in 2006. Other alleged threats have surfaced every so often since then. Why the ban continues is open to speculation. I view it as continuing security theater, more to placate fears than any real basis for terrorism. That said, it’s not difficult to locate an individual with an online presence who can show you how to take legitimate, authorized items you carry through TSA, combined with what you can legally buy from stores in TSA secured concourse areas of an airport, and cause mayhem, even bring down a commercial airliner with minimal difficulty. I do not see the restrictions being lifted anytime soon. It’s not about real airline safety. It’s about power and control. ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [January 5, 2015, 5:38am UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/3 "2015-01-05T05:38:55Z")
> [@coremelt](#): > > (GD Rant: Why do we spend so many billions and cause so much inconvenience on preventing wildly unlikely attacks on airliners, when spending a 10th as much on road safety or public transport improvements would save so many more lives? ) Because talking about infrastructure is boring, but scaring people about “The Terrorists” sells advertising. The same goes for why we can spend over a trillion dollars fighting wars over access to petroleum in the Middle East instead of investing a significant fraction of that amount developing production and distribution systems for alternative transportation fuels. Stranger ---
**Author:** ![grude](https://avatars.discourse-cdn.com/v4/letter/g/e47774/32.png) [@grude](https://boards.straightdope.com/u/grude)\ **Post date:** [January 5, 2015, 7:00am UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/4 "2015-01-05T07:00:30Z")
Go to the dollar store, buy some bottles of cough syrup or some other liquid med. Pour the meds in empty soda bottles at home, or just dump it down the drain your call. Fill bottles with liquids you want to carry on, tada! This worked as of 2009 anyway, medicines are exempt from the liquid limit. [http://www.tsa.gov/traveler-information/3-1-1-liquids-rule](http://www.tsa.gov/traveler-information/3-1-1-liquids-rule) > [@](#): > > Declare larger liquids. Medications, baby formula/food and breast milk are allowed in reasonable quantities exceeding three ounces, and they don’t have to be in the zip-top bag. Declare these items for inspection at the checkpoint. TSA officers may need to open them for additional screening. ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [January 5, 2015, 7:19am UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/5 "2015-01-05T07:19:18Z")
> [@coremelt](#): > > (GD Rant: Why do we spend so many billions and cause so much inconvenience on preventing wildly unlikely attacks on airliners, when spending a 10th as much on road safety or public transport improvements would save so many more lives? ) Dude, BE CAREFUL WHAT YOU WISH! T.S.A. has already been expanding their presence to include train stations, sporting events and other public venues. [T.S.A. Expands Duties Beyond Airport Security](http://www.nytimes.com/2013/08/06/us/tsa-expands-duties-beyond-airport-security.html?pagewanted=all), Ron Nixon, New York Times, Aug. 5, 2013. > [@](#): > > With little fanfare, the agency best known for airport screenings has vastly expanded its reach to sporting events, music festivals, rodeos, highway weigh stations and train terminals. Not everyone is happy. [Surprise! TSA Is Searching Your Car, Subway, Ferry, Bus, AND Plane](http://www.motherjones.com/mojo/2011/06/tsa-swarms-8000-bus-stations-public-transit-systems-yearly), Jen Quraishi, Mother Jones, June 20, 2011. > [@](#): > > Think you could avoid the TSA’s body scanners and pat-downs by taking Amtrak? Think again. Even your daily commute isn’t safe from TSA screenings. And because the TSA is working with Immigration and Customs Enforcement (ICE) and Border Patrol, you may have your immigration status examined along with your “junk”. ---
**Author:** ![coremelt](https://avatars.discourse-cdn.com/v4/letter/c/4491bb/32.png) [@coremelt](https://boards.straightdope.com/u/coremelt)\ **Post date:** [January 5, 2015, 8:04am UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/6 "2015-01-05T08:04:18Z")
> [@Senegoid](#): > > Dude, BE CAREFUL WHAT YOU WISH! > > T.S.A. has already been expanding their presence to include train stations, sporting events and other public venues. THAT IS NOT WHAT I MEANT !?!?!??! Compulsory advanced driver training courses (defensive driving and covering for other peoples mistakes) , converting single lane roads to dual carriageway and other safety measures to reduce the traffic death toll is what I meant. Fuck the TSA sideways… I don’t expect this madness to end anytime soon in the US, but even here on a domestic flight in Thailand today I had to throw away my oh so dangerous bottle of orange juice in case it turned into a deadly item at 30,000 feet… ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [January 5, 2015, 1:10pm UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/7 "2015-01-05T13:10:21Z")
> [@coremelt](#): > > THAT IS NOT WHAT I MEANT !?!?!??! > > Compulsory advanced driver training courses (defensive driving and covering for other peoples mistakes) , converting single lane roads to dual carriageway and other safety measures to reduce the traffic death toll is what I meant. Fuck the TSA sideways… > > (snip)… Technology is taking care of improving auto safety rather nicely lately. Cars are much better designed to protect it’s passengers and now some are actively taking control from the driver to prevent a collision. Self driving cars promise even greater safety (if they can deliver on that promise is open to debate, but I believe it will). We are getting where we are going safer and faster (since the ending of the fed’s 55 MPH speed limit restriction, and now in traffic conditions with traffic aware GPS). Cars are evolving fast and one can make the argument that money spent as you suggest could actually be counterproductive at this time as the way we drive appears to be ready to change. OTOH airline travel just appears to me to be technologically stalled compared to car travel. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [January 5, 2015, 1:46pm UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/8 "2015-01-05T13:46:27Z")
I only have time for a sound-bite post. Here it is: The quantity of liquid explosives required to blow a catastrophic hole in an airliner is surprisingly small. The intent is to make it difficult for bad guys to trivially carry on several times the required dose in a single container. ---
**Author:** ![steronz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/steronz/32/11765_2.png) [@steronz](https://boards.straightdope.com/u/steronz)\ **Post date:** [January 5, 2015, 1:57pm UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/9 "2015-01-05T13:57:48Z")
> [@LSLGuy](#): > > The intent is to make it difficult for bad guys to trivially carry on several times the required dose in a single container. [An expert](https://www.schneier.com/news/archives/2008/11/the_things_he_carrie.html) from a piece from The Atlantic on airport security with Bruce Schneier: > [@](#): > > Schneier took from his bag a **12-ounce container labeled “saline solution.”** > > “It’s allowed,” he said. Medical supplies, such as saline solution for contact-lens cleaning, don’t fall under the TSA’s three-ounce rule. > > **“What’s allowed?” I asked. “Saline solution, or bottles labeled saline solution?”** > > “Bottles labeled saline solution. They won’t check what’s in it, trust me.” > > They did not check. As we gathered our belongings, Schneier held up the bottle and said to the nearest security officer, “This is okay, right?” “Yep,” the officer said. “Just have to put it in the tray.” > > “Maybe if you lit it on fire, he’d pay attention,” I said, risking arrest for making a joke at airport security. ( **Later, Schneier would carry two bottles labeled saline solution—24 ounces in total—through security. An officer asked him why he needed two bottles. “Two eyes,” he said.** He was allowed to keep the bottles.) Seems pretty trivial to me. ---
**Author:** ![Gray\_Ghost](https://avatars.discourse-cdn.com/v4/letter/g/c0e974/32.png) [@Gray\_Ghost](https://boards.straightdope.com/u/Gray_Ghost)\ **Post date:** [January 5, 2015, 1:59pm UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/10 "2015-01-05T13:59:53Z")
> [@LSLGuy](#): > > …The quantity of liquid explosives required to blow a catastrophic hole in an airliner is surprisingly small. The intent is to make it difficult for bad guys to trivially carry on several times the required dose in a single container. I’m not an expert in either aviation or security, but as a lay person, liquid explosives don’t concern me near as much as accelerants. How bad of a cabin fire could someone cause with 3.5 oz of improvised jellied gasoline? I wouldn’t be surprised though if it were a lot more difficult to cause a conflagration than it seems. ---
**Author:** ![Ravenman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ravenman/32/2929_2.png) [@Ravenman](https://boards.straightdope.com/u/Ravenman)\ **Post date:** [January 5, 2015, 2:42pm UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/11 "2015-01-05T14:42:31Z")
> [@Gray\_Ghost](#): > > I’m not an expert in either aviation or security, but as a lay person, liquid explosives don’t concern me near as much as accelerants. How bad of a cabin fire could someone cause with 3.5 oz of improvised jellied gasoline? While I can’t address the logic of the concern about small amounts of liquid being brought on an airplane, I think you are totally off-base in your concern here. [This](https://www.youtube.com/watch?v=d0j_nKYV73I#t=20s) is what three ounces of explosive can do. [This](https://www.youtube.com/watch?v=qOxQO5vYfDA#t=42s) is probably 6-8 ounces of gasoline. Granted, nobody wants a fire on an aircraft, but that’s why planes have fire extinguishers. You can respond to a passenger’s seat being set on fire, you can’t undo a hole in a fuselage caused by an explosion. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [January 5, 2015, 2:59pm UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/12 "2015-01-05T14:59:32Z")
> [@grude](#): > > Go to the dollar store, buy some bottles of cough syrup or some other liquid med. Pour the meds in empty soda bottles at home, or just dump it down the drain your call. > > Fill bottles with liquids you want to carry on, tada! > > This worked as of 2009 anyway, medicines are exempt from the liquid limit. **Moderator Note** **grude** , let’s not provide information on how to evade regulations. No warning issued, but don’t do this again. Colibri General Questions Moderator ---
**Author:** ![coremelt](https://avatars.discourse-cdn.com/v4/letter/c/4491bb/32.png) [@coremelt](https://boards.straightdope.com/u/coremelt)\ **Post date:** [January 5, 2015, 3:14pm UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/13 "2015-01-05T15:14:30Z")
No Damnit this is GQ, I want some cites with hard information not vague scare tactics. So what if you can get 1 or 2 500 ml bottles through security by labelling it as Saline? Wheres the actual evidence that with 1 litre of an accelerant or 1 litre of an liquid explosive you could bring a plane down? As far as I understand a very small hole in the fuselage does not result in losing the plane, it results in air escaping and the plane doing an emergency descent. Yeah you could start a fire, but you can do that just fine despite the liquid bans. Just buy a bottle of hairspray and a lighter when past security and you have a small flame thrower. It’s going to cause a panic but its not going to bring a plane down. And that explosive video didn’t look that impressive to me, again maybe kill 1 or 2 people and cause a fuselage leak but not enough to bring an airliner down. ---
**Author:** ![Ramira](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ramira/32/344_2.png) [@Ramira](https://boards.straightdope.com/u/Ramira)\ **Post date:** [January 5, 2015, 3:18pm UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/14 "2015-01-05T15:18:54Z")
> [@Ravenman](#): > > While I can’t address the logic of the concern about small amounts of liquid being brought on an airplane, I think you are totally off-base in your concern here. [This](https://www.youtube.com/watch?v=d0j_nKYV73I#t=20s) is what three ounces of explosive can do. [This](https://www.youtube.com/watch?v=qOxQO5vYfDA#t=42s) is probably 6-8 ounces of gasoline. > > Granted, nobody wants a fire on an aircraft, but that’s why planes have fire extinguishers. You can respond to a passenger’s seat being set on fire, you can’t undo a hole in a fuselage caused by an explosion. how does throwing away the water bottles and other things like this stop the easy concealing of the c-4 or even the petrol in the anal cavity with the methods known since the days of [Henri Charrière](http://en.wikipedia.org/wiki/Papillon_%28book%29)? There is already the bomb sniffing dogs and the other technology. ---
**Author:** ![grude](https://avatars.discourse-cdn.com/v4/letter/g/e47774/32.png) [@grude](https://boards.straightdope.com/u/grude)\ **Post date:** [January 5, 2015, 3:32pm UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/15 "2015-01-05T15:32:04Z")
> [@Colibri](#): > > **Moderator Note** > > **grude** , let’s not provide information on how to evade regulations. No warning issued, but don’t do this again. > > Colibri > General Questions Moderator Sorry, I got carried away trying to point out the security theater. ---
**Author:** ![Ravenman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ravenman/32/2929_2.png) [@Ravenman](https://boards.straightdope.com/u/Ravenman)\ **Post date:** [January 5, 2015, 3:53pm UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/16 "2015-01-05T15:53:37Z")
> [@coremelt](#): > > No Damnit this is GQ, I want some cites with hard information not vague scare tactics. So what if you can get 1 or 2 500 ml bottles through security by labelling it as Saline? This is a very poor answer to the question you’re asking, but think about the volume you’re talking about. A 1.25 pound block of C-4 is about half a liter in size. Nitroglycerin has about the same energy density as C-4. PETN, which is not a liquid, but is what was used in the underwear bomb plot, is about 15% more energy dense than C-4, but makes about the same size boom. If your question is how much explosive power can be contained in 500ml or 1l of volume, it is a lot. [This](https://www.youtube.com/watch?v=-4s76fc8kB0) is what a half pound of explosive can do to an enclosed space. > [@Ramira](#): > > how does throwing away the water bottles and other things like this stop the easy concealing of the c-4 or even the petrol in the anal cavity with the methods known since the days of [Henri Charrière](http://en.wikipedia.org/wiki/Papillon_%28book%29)? There is already the bomb sniffing dogs and the other technology. As I said, I can’t speak to the security procedures, but I do think that folks are underestimating the power of explosives here. ---
**Author:** ![coremelt](https://avatars.discourse-cdn.com/v4/letter/c/4491bb/32.png) [@coremelt](https://boards.straightdope.com/u/coremelt)\ **Post date:** [January 5, 2015, 3:59pm UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/17 "2015-01-05T15:59:43Z")
> [@Ravenman](#): > > This is a very poor answer to the question you’re asking, but think about the volume you’re talking about. A 1.25 pound block of C-4 is about half a liter in size. Nitroglycerin has about the same energy density as C-4. PETN, which is not a liquid, but is what was used in the underwear bomb plot, is about 15% more energy dense than C-4, but makes about the same size boom. If your question is how much explosive power can be contained in 500ml or 1l of volume, it is a lot. yes but all those threats are already controlled for by the cabin baggage x ray screening, random explosive swabs, explosive sniffing dogs, etc etc. We are talking in this thread SOLELY about liquids and I’m not aware of the energy density of any liquid explosives being even remotely comparable to C4 or Nitroglycerin. If I’m wrong then please fight my ignorance. ---
**Author:** ![Ramira](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ramira/32/344_2.png) [@Ramira](https://boards.straightdope.com/u/Ramira)\ **Post date:** [January 5, 2015, 4:10pm UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/18 "2015-01-05T16:10:46Z")
> [@Ravenman](#): > > As I said, I can’t speak to the security procedures, but I do think that folks are underestimating the power of explosives here. Maybe but it is a component of the OP question. > [@coremelt](#): > > yes but all those threats are already controlled for by the cabin baggage x ray screening, random explosive swabs, explosive sniffing dogs, etc etc. . I can only observe that I fly very frequently for work to many places with the active threats to the security including bombing of the airplanes. Only to the USA do they bother with the liquids rules. I guess this is for the americans rules that are imposed for flights to the usa. otherwise it is the monitoring, the dog sniffing, the xrays and the scanners. ---
**Author:** ![steronz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/steronz/32/11765_2.png) [@steronz](https://boards.straightdope.com/u/steronz)\ **Post date:** [January 5, 2015, 4:11pm UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/19 "2015-01-05T16:11:39Z")
Pre-9/11, all you needed to hijack a plane was a knife. Take somebody hostage, threaten to slit their throat, and the pilot will take the plane wherever you want it to go. Replace knife with 1 liter of liquid explosive and I don’t see how it’s any different. Post-9/11 the threat is now that the hijackers will take over the controls and crash the plane, so threatening a flight attendant or passenger with a knife or liquid explosive is not going to be as effective. But couldn’t a liquid explosive break the lock on the cockpit door? eta: It’s a stupid rule because it’s nearly unenforceable in it’s current implementation and the threat is so unlikely, but if you don’t think you could do something nefarious with a few liters of liquid explosive you’re not being creative enough. ---
**Author:** ![coremelt](https://avatars.discourse-cdn.com/v4/letter/c/4491bb/32.png) [@coremelt](https://boards.straightdope.com/u/coremelt)\ **Post date:** [January 5, 2015, 4:18pm UTC](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008/20 "2015-01-05T16:18:35Z")
> [@Ramira](#): > > Only to the USA do they bother with the liquids rules. I guess this is for the americans rules that are imposed for flights to the usa. otherwise it is the monitoring, the dog sniffing, the xrays and the scanners. No, the liquid rules have spread to various other places. As I already mentioned upthread today in a domestic flight within Thailand I had to surrender a 500 ml bottle of orange juice for no good reason. [Next page](https://boards.straightdope.com/t/airline-fluid-restrictions-do-they-serve-any-purpose/709008.md?page=2)