# So just what do the new airport scanners catch that a metal detector can't? **URL:** \ **Category:** Factual Questions\ **Created:** [November 17, 2010, 11:10pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032 "2010-11-17T23:10:06Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Zyada](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zyada/32/3028_2.png) [@Zyada](https://boards.straightdope.com/u/Zyada)\ **Post date:** [November 17, 2010, 11:10pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/1 "2010-11-17T23:10:06Z")
I was talking with some people today about this, and I realized - just what is it supposed to see differently? A metal detector will find any normal gun. Are there guns that don’t set off metal detectors? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [November 17, 2010, 11:14pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/2 "2010-11-17T23:14:24Z")
Guns? Probably not, but bombs - yes. ---
**Author:** ![Zyada](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zyada/32/3028_2.png) [@Zyada](https://boards.straightdope.com/u/Zyada)\ **Post date:** [November 17, 2010, 11:20pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/3 "2010-11-17T23:20:29Z")
Why bombs? What does it see? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [November 17, 2010, 11:28pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/4 "2010-11-17T23:28:02Z")
> [@Zyada](#): > > Why bombs? What does it see? They can detect materials with differing densities / composition from flesh. Basically, the detectors give an under-the-clothes and over-the-skin image, showing any plastic or metal objects, including explosives. ---
**Author:** ![Fubaya](https://avatars.discourse-cdn.com/v4/letter/f/c2a13f/32.png) [@Fubaya](https://boards.straightdope.com/u/Fubaya)\ **Post date:** [November 17, 2010, 11:31pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/5 "2010-11-17T23:31:34Z")
Testicles. ---
**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:** [November 17, 2010, 11:46pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/6 "2010-11-17T23:46:14Z")
[Let the TSA tell you in their own words and pictures](http://www.tsa.gov/approach/tech/ait/index.shtm). ---
**Author:** ![Balthisar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/balthisar/32/2825_2.png) [@Balthisar](https://boards.straightdope.com/u/Balthisar)\ **Post date:** [November 18, 2010, 12:21am UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/7 "2010-11-18T00:21:46Z")
It can’t find things stuffed up your rectum. So much that. ---
**Author:** ![iamnotbatman](https://avatars.discourse-cdn.com/v4/letter/i/858c86/32.png) [@iamnotbatman](https://boards.straightdope.com/u/iamnotbatman)\ **Post date:** [November 18, 2010, 3:08am UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/8 "2010-11-18T03:08:18Z")
It can see your large (C4-filled prosthetic, but they don’t know that) penis. ---
**Author:** ![Vicullum](https://avatars.discourse-cdn.com/v4/letter/v/6de8d8/32.png) [@Vicullum](https://boards.straightdope.com/u/Vicullum)\ **Post date:** [November 18, 2010, 11:00am UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/9 "2010-11-18T11:00:38Z")
One criticism I heard leveled against the machines is that it won’t detect anything hidden within your fat folds, swallowed, or up your rear. I shudder to think how the next generation machines will “solve” those problems. ---
**Author:** ![Quercus](https://avatars.discourse-cdn.com/v4/letter/q/7ab992/32.png) [@Quercus](https://boards.straightdope.com/u/Quercus)\ **Post date:** [November 18, 2010, 2:12pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/10 "2010-11-18T14:12:20Z")
**So just what do the new airport scanners catch that a metal detector can’t?** Profits for the new scanner manufacturer. ---
**Author:** ![EvilTOJ](https://avatars.discourse-cdn.com/v4/letter/e/ee59a6/32.png) [@EvilTOJ](https://boards.straightdope.com/u/EvilTOJ)\ **Post date:** [November 18, 2010, 2:15pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/11 "2010-11-18T14:15:30Z")
I love this bit off the TSA site; “Since imaging technology has been deployed at airports, over 99 percent of passengers choose to be screened by this technology over alternative screening procedures.” They neglect to mention that the alternative is getting a pat down just like they do when you’re arrested. That’s like saying “When given a choice between being punched in the face or eating a large bug, people overwhelmingly chose eating the large bug! The system works!” ---
**Author:** ![Leaffan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leaffan/32/299_2.png) [@Leaffan](https://boards.straightdope.com/u/Leaffan)\ **Post date:** [November 18, 2010, 2:44pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/12 "2010-11-18T14:44:53Z")
There are actually people out there who are vehemently opposed to these new scanners because (gasp!) the security people can see my naked skin! Jesus Christ people, grow the fuck up. Like it matters to me if some underpaid security clerk in a booth at the Ottawa International Airport sees a grainy, black-and-white image of my willy on a 14" monitor. ---
**Author:** ![mnemosyne](https://avatars.discourse-cdn.com/v4/letter/m/c4cdca/32.png) [@mnemosyne](https://boards.straightdope.com/u/mnemosyne)\ **Post date:** [November 18, 2010, 3:25pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/13 "2010-11-18T15:25:08Z")
> [@EvilTOJ](#): > > I love this bit off the TSA site; “Since imaging technology has been deployed at airports, over 99 percent of passengers choose to be screened by this technology over alternative screening procedures.” > > They neglect to mention that the alternative is getting a pat down just like they do when you’re arrested. That’s like saying “When given a choice between being punched in the face or eating a large bug, people overwhelmingly chose eating the large bug! The system works!” Most airports are still using metal detectors and a basic pat down, and there’s no way that 99% of passengers are actually using the imaging technology. I presume that 99% is the number of people who chose the backscatter after they were unfortunate enough to be part of the 10% who were pulled aside and given the choice off the backscatter or a pat down, otherwise they are told they can’t get on the plane, if they refuse the search entirely they may be fined and possibly arrested. Which would you choose in that case? Personally, I haven’t made up my mind about the whole thing. It’s interesting technology, but I’m not sure it would really be effective at preventing another terrorist attack. I’m not sure how I’d feel if I were selected to go through one (though I _always_ get stopped for a pat down and a bag check, so I assume it’s just a matter of time for me…apparently a slightly chubby, pale, blue eyed white chick is a suspicious thing. I suspect I’m the “control” - they can’t be accused of profiling everyone else, 'cause, “Hey! We searched HER!”) I support the pilot’s associations, who are nearly unanimously speaking out against backscatter screening for their members, given as they would be subject to it nearly every work day (and possibly more than once a day). The amount of radiation may be small, but remember that pilots spend a lot of time at cruising altitudes, and are already exposed to higher levels of radiation than the average person due to that. Repeatedly having to be screened in this manner becomes a health risk, sooner or later. Besides, they are the _pilots_. If they want to use the plane as a missile, who’s going to stop them? ---
**Author:** ![Markxxx](https://avatars.discourse-cdn.com/v4/letter/m/5daacb/32.png) [@Markxxx](https://boards.straightdope.com/u/Markxxx)\ **Post date:** [November 18, 2010, 3:30pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/14 "2010-11-18T15:30:44Z")
You have to remember terrorists are not looking to take over a plane. That is almost certain to never happen again. The passengers will assume anyone with a gun is gonna do a 9-11 again and just rush the guy and probably kill him as he takes a few out. Terrorists want to blow it up while in the sky. Terrorism relies on fear. What could be more fearsome than knowning anytime on your trip you could be blown to bits If the bomb goes off and the plane blows up, well there’s nothing anyone can do. So the TSAs are (or should be) looking for the newest technologies in bomb making. Something that could explode but will be so ordinary looking that it won’t register to the eye or be found out through detection. ---
**Author:** ![ethelbert](https://avatars.discourse-cdn.com/v4/letter/e/958977/32.png) [@ethelbert](https://boards.straightdope.com/u/ethelbert)\ **Post date:** [November 18, 2010, 3:35pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/15 "2010-11-18T15:35:56Z")
> [@Leaffan](#): > > There are actually people out there who are vehemently opposed to these new scanners because (gasp!) the security people can see my naked skin! > > Jesus Christ people, grow the fuck up. Like it matters to me if some underpaid security clerk in a booth at the Ottawa International Airport sees a grainy, black-and-white image of my willy on a 14" monitor. To be fair, it is probably not a grainy image and it is likely on a larger monitor (hey, my willy demands a larger monitor), but yeah, what people are afraid of is their own imagination. Unless these pictures make their way out onto the internet and you can recognize the people, I don’t see the problem. Of course, if that happened, my brag about my willy would be revealed for the nonsense it is. ---
**Author:** ![L\_Driver](https://avatars.discourse-cdn.com/v4/letter/l/ba9def/32.png) [@L\_Driver](https://boards.straightdope.com/u/L_Driver)\ **Post date:** [November 18, 2010, 3:41pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/16 "2010-11-18T15:41:13Z")
They are supposed to be able to see plastic things that you may have hidden, like the underwear bomber last year in Detroit. I am personally nervous about this whole thing. I have some flights coming up for thanksgiving and I will be hitting Chicago and Detroit airports so I am assuming I will be up against this twice. I have read people’s accounts and the ‘enhanced’ pat downs sound inappropriate and rude and the scanner is just too much showing, plus what about potential health risks? There was a story about the difference between the actual photos they take and the ones they show you they take: [i-am-bored.com](http://www.i-am-bored.com/bored_link.cfm?link_id=46379). Makes me nervous, for sure. ---
**Author:** ![groman](https://avatars.discourse-cdn.com/v4/letter/g/73ab20/32.png) [@groman](https://boards.straightdope.com/u/groman)\ **Post date:** [November 18, 2010, 3:57pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/17 "2010-11-18T15:57:41Z")
> [@Markxxx](#): > > Terrorists want to blow it up while in the sky. Terrorism relies on fear. What could be more fearsome than knowning anytime on your trip you could be blown to bits Lots of things. I am more thousands of times more likely to die of food-borne illness or a car crash. I am more likely to be randomly killed by lightning. I am more likely to choke on my food. More on topic, pilot error, air traffic control error or negligence, mechanic error or negligence, food poisoning from airline food, catching TB from the person next to me – a lot more fearsome and a lot more likely. Hell, you’re probably more likely to be arrested, tried and wrongfully convicted for murder of a person you have never even met – and that can happen _any minute now,_ than you are to be blown to bits flying. ---
**Author:** ![Leaffan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leaffan/32/299_2.png) [@Leaffan](https://boards.straightdope.com/u/Leaffan)\ **Post date:** [November 18, 2010, 4:09pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/18 "2010-11-18T16:09:11Z")
Re. health issues of backscatter X-ray: From [Wiki:](http://en.wikipedia.org/wiki/Backscatter_X-ray) > [@](#): > > 1. Naturally occurring ionizing radiation is all around us. We are continuously exposed to this background radiation during ordinary living. In 42 minutes of ordinary living, a person receives more radiation from naturally occurring sources than from screening with any general-use x-ray security system. > 2. The national radiation safety standard (see below) sets a dose per screening limit for the general-use category. To meet the requirements of the general-use category a full-body x-ray security system must deliver less than the dose a person receives during 4 minutes of airline flight. TSA has set their dose limit to ensure a person receives less radiation from one scan with a TSA general-use x-ray security system than from 2 minutes of airline flight. > 3. A person would have to be screened more than a thousand times in one year in order to exceed the annual radiation dose limit for people screening that has been set by expert radiation safety organizations. From [How Stuff Works](http://science.howstuffworks.com/innovation/backscatter.htm): > [@](#): > > Using the HPS numbers, it would take 200 backscatter scans in a year to reach a negligible dose – 1 mrem – of radiation. You receive 1 mrem from three hours on an airplane, from two days in Denver or from three days in Atlanta. In other words, the health risks are completely non-existent. ---
**Author:** ![aruvqan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aruvqan/32/2891_2.png) [@aruvqan](https://boards.straightdope.com/u/aruvqan)\ **Post date:** [November 18, 2010, 5:42pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/19 "2010-11-18T17:42:17Z")
> [@Leaffan](#): > > Re. health issues of backscatter X-ray: > > From [Wiki:](http://en.wikipedia.org/wiki/Backscatter_X-ray) > > From [How Stuff Works](http://science.howstuffworks.com/innovation/backscatter.htm): > > In other words, the health risks are completely non-existent. Who trains the TSA idiots in using the machine? Who calibrates the machine? Who certifies the TSA users and the calibration labs and maintenance personnel that maintain the machines? How difficult would it be to crank up the gain and overdose someone? Any other radiological device in the US the operators are highly trained, and certified. The callibration labs are staffed by trained personnel and they themselves are certified, and the cal labs are certified. ---
**Author:** ![Leaffan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leaffan/32/299_2.png) [@Leaffan](https://boards.straightdope.com/u/Leaffan)\ **Post date:** [November 18, 2010, 5:54pm UTC](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032/20 "2010-11-18T17:54:54Z")
That’s a lot of woo woo, man. You think you’re the first person to think of all this? I work in the nuclear industry. There’s not a chance in hell these machines would be approved if there was any possibility that they could provide damaging doses of radiation. Get a grip. [Next page](https://boards.straightdope.com/t/so-just-what-do-the-new-airport-scanners-catch-that-a-metal-detector-cant/561032.md?page=2)