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TSA's security rules are a mix of deterrents and science. I worked on explosive detection devices for the TSA during my PhD. The banning of liquids and pastes

by physcab 14y ago

TSA's security rules are a mix of deterrents and science. I worked on explosive detection devices for the TSA during my PhD. The banning of liquids and pastes are logical. There are some extremely volatile liquid and plastic explosives that would take your leg off if you dropped [1][2]. Or if they were used as primary explosives to ignite a more powerful secondary explosive. That could be disastrous if TSA allowed liquids in larger quantities. As for the detection technologies that are currently out on the market, all I have to say is that every single one of them can be confused and circumvented, which is why they have seemingly arbitrary rules. For example, xray technologies can easily confuse plastic explosives with a piece of cheese, which is why you have to take shit out of your bag. MMW wave technologies are confused by water substances, which is why you have to do a pat down if an anomaly is detected. My own technology that I worked on was primarily developed as a low-cost surface technique, so if you had explosive residue on your hands or baggage our detector would alarm. [1]http://en.wikipedia.org/wiki/Nitroglycerin http://en.wikipedia.org/wiki/Nitroglycerin [2]http://www.youtube.com/watch?v=oa6fcun3kag http://www.youtube.com/watch?v=oa6fcun3kag

dinkumthinkum 14y ago
So having multiple containers having one container as long as the carrier says it is baby formula prevents such an explosion? I'm not entirely certain that they stands up to the "mix of deterrents and science" test, though.
Corrado 14y ago
I don't think that anyone is denying that liquids can pose a threat. The article stated that by allowing everyone to bring some small amounts of liquides defeats the purpose almost completely. All I would have to do is get 5 of my co-conspirators to carry on 5 little contains each of some volatile liquid and when we get past security we pour them all together to make one big batch of nastiness. This example, and many more, is why we say the TSA's security rules are useless and arbitrary. About the only way to ensure a risk free flight is to force everyone to fly naked, not allow luggage, remove the cleaning crew, etc... and I don't think there are any airlines that are willing to go that far. :/
- pavel_lishin 14y ago
  Or just carry the five containers yourself, by carrying a bottle of shampoo, conditioner, moisturizer, suntan lotion, and toothpaste. All non-transparent containers - I've never seen a TSA agent sniff toothpaste to make sure it was actually toothpaste, and not superglue, or cocaine, or strawberry jam.
aplusbi 14y ago
Do you agree that the best way to dispose of liquid explosives is to carelessly toss them into a large trashcan in the middle of a large crowd?
- danielweber 14y ago
  That's not quite right. Very few people are found carrying guns through metal-detectors, but this doesn't mean that metal detectors have no place in stopping guns from planes. The step that screens liquids isn't going to actually find explosive liquids; it is going to stop all liquids, so the bombers won't be bringing them through in the first place. I can hear lots of good arguments that the restrictions on liquids doesn't pass a cost-benefit analysis, but once you make the decision to stop liquids, having a common disposal place really isn't the problem. Someone could just suicide-bomb the security line in the first place.
anamax 14y ago
> My own technology that I worked on was primarily developed as a low-cost surface technique, so if you had explosive residue on your hands or baggage our detector would alarm. (1) I just got back from DisneyWorld. One night the fireworks smoke drifted across where I was standing.... (2) The person who packaged the explosives need not be the person carrying them.
D_Alex 14y ago
"The banning of liquids and pastes are logical. There are some extremely volatile liquid and plastic explosives..." What utter garbage. Solids, SOLIDS should be banned! Azides, fulminates, picrates and the like are all SOLIDS and extremely UNSAFE, they can take both your legs off and more. I propose that no single SOLID piece weighting more than 4 ounces should be allowed on board, though of course several such smaller pieces are not a problem.

by physcab 14y ago

dinkumthinkum 14y ago

So having multiple containers having one container as long as the carrier says it is baby formula prevents such an explosion? I'm not entirely certain that they stands up to the "mix of deterrents and science" test, though.

Corrado 14y ago

I don't think that anyone is denying that liquids can pose a threat. The article stated that by allowing everyone to bring some small amounts of liquides defeats the purpose almost completely. All I would have to do is get 5 of my co-conspirators to carry on 5 little contains each of some volatile liquid and when we get past security we pour them all together to make one big batch of nastiness. This example, and many more, is why we say the TSA's security rules are useless and arbitrary. About the only way to ensure a risk free flight is to force everyone to fly naked, not allow luggage, remove the cleaning crew, etc... and I don't think there are any airlines that are willing to go that far. :/

pavel_lishin 14y ago
Or just carry the five containers yourself, by carrying a bottle of shampoo, conditioner, moisturizer, suntan lotion, and toothpaste. All non-transparent containers - I've never seen a TSA agent sniff toothpaste to make sure it was actually toothpaste, and not superglue, or cocaine, or strawberry jam.

aplusbi 14y ago

Do you agree that the best way to dispose of liquid explosives is to carelessly toss them into a large trashcan in the middle of a large crowd?

danielweber 14y ago
That's not quite right. Very few people are found carrying guns through metal-detectors, but this doesn't mean that metal detectors have no place in stopping guns from planes. The step that screens liquids isn't going to actually find explosive liquids; it is going to stop all liquids, so the bombers won't be bringing them through in the first place. I can hear lots of good arguments that the restrictions on liquids doesn't pass a cost-benefit analysis, but once you make the decision to stop liquids, having a common disposal place really isn't the problem. Someone could just suicide-bomb the security line in the first place.

anamax 14y ago

> My own technology that I worked on was primarily developed as a low-cost surface technique, so if you had explosive residue on your hands or baggage our detector would alarm. (1) I just got back from DisneyWorld. One night the fireworks smoke drifted across where I was standing.... (2) The person who packaged the explosives need not be the person carrying them.

D_Alex 14y ago

"The banning of liquids and pastes are logical. There are some extremely volatile liquid and plastic explosives..." What utter garbage. Solids, SOLIDS should be banned! Azides, fulminates, picrates and the like are all SOLIDS and extremely UNSAFE, they can take both your legs off and more. I propose that no single SOLID piece weighting more than 4 ounces should be allowed on board, though of course several such smaller pieces are not a problem.