Simple Math March 10, 2011 6:56 AM

Wow. Only $1 billion to find 130 items? That’s almost $7.7 million per item. Could one imagine anything more cost effective?

BF Skinner March 10, 2011 7:11 AM

So in 2006 – subway searches were upheld because “the risk to public safety is substantial and real.”

This is axiomatically wrong. I grant you real for a given value of real. But substantial in the way that spam or botnets are substantial? In a way that can be, no strike that, IS measured everyday?

Yet with metro rail systems in every major city in the US one has yet to go boom. Even in the presumedly high target areas of New York and Washington DC.

Perhaps the Court will make the correct decision here but I’m pessimistic. Like security, law is rarely purely about principal and more about people.

Clive Robinson March 10, 2011 7:22 AM

@ Simple Math,

“Could one imagine anything more cost effective?”

Err the hunt for WMD perhaps might be top of the liist, and somewhere towards the bottom depending on how you calculate it the hunt for “old man bin liner”…

Clive Robinson March 10, 2011 7:33 AM

@ BF Skinner,

“Like security, law is rarely purely about principal and more about people”

The other problem is even if it was about law and the judge given a sufficiently broad remit it would be based on the balance of argument presented.

And as we have found in the UK it’s a bit difficult to counter evidence you cann’t see and cann’t be told about due to “methods and sources” that a judge decides to accept.

The thing with that though is how do you know/show if what the judge is being told is closer to fantasy or fact…

Clive Robinson March 10, 2011 8:50 AM

Asside from the privacy argument there are the two other issues of safety and efficacy.

The safety one is difficult to judge because a lot of the information needed to evaluate the risk has been deliberatly withheld (not a good sign) and secondly independent studies in reality (whole life organism on mice etc) are going to take a minimum of five years to compleate.

But the comparison to medical radiological scans is a false one primarily because of the risk evaluation.

Simplisticaly you are only given a medical radiological scan if there is sufficient reason to belive you have come to harm from physical insult, pathogen or the result of an erant biological process.

It can easily be argued that your wellbeing if not your life has already been impacted and thus the significant risk of a medical radiological scan can be justified as an “exceptional event for an individual” that “lowers the overall risk factors”.

Neither of these major points be made for a member of the traveling public. For though it may be true that a certain percentage of the populous never flies it can also be shown that some people may make several flights in one day on a regular if not daily basis. I am unaware of any person having been medicaly radiologicaly scanned every day of their working lives. Further based on current figures of the number of passenger flights compared to the number of inflight deaths due to terrorism it is difficult to see how the case can be made for an “overall risk factors”.

It is interesting to note a judges previous comments when it was suggested that these radiological scanners be introduced to court houses. They made the quite false comment about choice implying that people did not have choice in attending court where as they do to fly. The simple fact is it is only the defendant and some witnesses who does not have choice and they appear very infrequently as individuals. Everyone else in the court chose to be there by their choice of proffession. For whatever reason they chose it nobody forced them to be what they are proffessionaly, and thus they can always change proffession if they so wish with little adverse effect to their overall risk. This cannot be said for airline passengers who chose not to fly but still have to travel.

Likewise the risks of eating a banana, not least because we consume it not rub it all over our skin to get an even dosage to the skin. And on the flip side it can be easily shown that there are very marked risk factor differences between external and internal exposure to some radiological substances such as Polonium 210. That is you could quite easily hold a small sample of it up against yourself for a considerable period of time but as we know ingestion of even a small ammount is likley to prove fatal unless it is very small. And as noted above the information required to even attempt to make a valid analysis has been deliberatly withheld.

As for efficacy, the first thing to note is that all security systems are doomed to fail against an intelligent adversary who can have unlimited attempts.

So the question arises as to advantage it gives against the adversary. To do this you have to evaluate the adversary and their aims and objectives.

On which the first point to note is that they win if they kill themselves but they also win if they get caught. Opps win-win to the adversary, game over.

The second point to note is the deterant factor, they are suicide bombers who will win if they kill themselves and win if they don’t, thus it can be seen that there can be no deterant factor in these devices.

Which brings up the question of advantage to others. That is other fare paying passengers and those paid to assist them to get from A to B. As has been so often noted aircraft only carry so many people, and you get atleast that number standing in the que to these scanners. Thus it only takes a small amount of reasoning to show these scanners are not their to protect either the passengers or those paid to assist them, as a suicide bomber is going to win just as easily by predetonating in the crowd or the scanner.

So their actuall efficacy is not good and is actually not directed where the US public are actually being told…

This then brings up the question of who should realy be paying for them and will the market bare the cost?

Afterall most of those pro these scanners also apear to be very much in favour of “freemarket ideals” thus perhaps it should be a freemarket choice not a federaly mandated handout to a chosen few.

Chris March 10, 2011 8:55 AM

I’m just waiting for the inevitable day when a determined terrorist decides to keister some C4.

What then? Mandatory cavity searches?

Remember, if you oppose this, you hate America and freedom and apple pie and children, AND you have something to hide. You don’t have something to hide, do you sir?

BF Skinner March 10, 2011 8:59 AM

@chris ” Mandatory cavity searches?”

Would it surprise you that TSA has already considered this?

It did me and it shouldn’t have. I don’t think it was to Hawley maybe the current administrator but someone asked point blank about cavity searches (or ‘better’ technology) and he laughed it off saying “Congress would never let us do that.”

I wonder if they went as far as a feasibility study?

Chris March 10, 2011 9:47 AM

@BF Skinner: “Would it surprise you that TSA has already considered this?”

Didn’t even bat an eye. Like I said, we’re all just one butt-bomber away from an amateur colonoscopy.

For our own safety, of course.

TP March 10, 2011 10:10 AM

@Simple Math

Yes, and 125 of those “130 prohibited items” were non-threatening-but-prohibited bullshit like nail clippers and shampoo bottles, with the remaining 5 being drugs. (No weapons, naturally; the TSA has yet to catch an actual terrorist.)

Clive Robinson March 10, 2011 10:19 AM

Speaking of things medical the hospital thinks… that I’m not going to suffer any more unexpected events for the very short while so have “let me out with a caution” of not to do anything that might cause a reoccurance of the aformentioned unexpected event…

And about 12 years ago I had a reason to look up the “risk factor” of a colonoscopy (affectionatly refered to as nine foot of garden hose the wrong way up your exhaust) and the normalised serious risk (ie death or disablment) was around 3% other risks were as high as 20%.

I would therefore say that unless there have been large strides in this particular medical practice then it is not likley to be something you would want done by anybody but a well trained and well practiced medical practitioner…

Oh and as was said in desperation in the film “Evolution” by one of the lead actors when face down on a gurny “there’s always time for lubrication” (and there was also the post op request for ice cream 8).

BF Skinner March 10, 2011 10:46 AM

@clive “let me out with a caution”

Because it’s YOUR fault that you were in there in the first place?

“We do not wish to release him.”
“Sister, prisoners are released. Patients are discharged!”
“That’s what we are afraid of.”

Hasufin March 10, 2011 10:52 AM

What worries me the most about these security measures is that the Powers That Be (and Should Not Be) have shown no interest in listening to the concerns or will of the public.
There has been huge opposition to these scanners. Is the TSA saying “Well, okay, we’ll re-evaluate and consider your concerns?”
No. they’re just insisting that the concerns are wrong, and keeping it up, conveniently managing to avoid using these “critical security measures” at times when they’d cause outrage, even though this of course compromises the security for which the scanners are needed.

For another similar case, look to WMATA in Washington DC. A couple of years ago, WMATA announced that they’d be performing random bag checks on metro riders. It rapidly became apparent that the people actually riding the Metro didn’t want this at all. WMATA ignored this… but didn’t perform any actual bag searches. Earlier this year, they announced they would start actually searching bags. Of course this caused an outcry… which WMATA is now waiting out, until they can quietly start searching bags.

Now, I don’t mean to say that all searches are wrong, or that all public opposition is right. But I keep seeing cases like these, in which the decision to intrude upon privacy was MADE without any public input, and right now those making such decisions seem to believe that the best course of action is to oppose and ignore public input rather than listen to it.

JeffH March 10, 2011 11:36 AM

@BF Skinner: “Would it surprise you that TSA has already considered this?”

Not even remotely. Nothing the TSA does would surprise me.

Strike that – the TSA would certainly surprise me if they issued the following statement:

“Sorry, folks. We just fiogured out that we’re totally ineffective, an incredible invasion of privacy, and a complete waste of time and money. We’re disbanding the TSA, and refunding the trillions you’ve wasted on us.”

Can’t say for certain, but I’m pretty sure I’d just flat our faint on the spot. plop. Auntie Em – am I finally back in Kansas?

George March 10, 2011 12:33 PM

Reading these articles makes me look forward even more to the staycations I have planned this year!

Clive Robinson March 10, 2011 1:02 PM

@ JeffH,

“Auntie Em – am I finally back in Kansas”

Arn’t you supposed to be wearing ruby read girrly boots with kitten heals or whater they were called?

(also helps to have a name like Dorothy if I remember correctly).

HJohn March 10, 2011 2:35 PM

@Simple Math: “Wow. Only $1 billion to find 130 items? That’s almost $7.7 million per item. Could one imagine anything more cost effective?”

Up front, let me state that the scanners are absolutely a waste of money and an unnecessary violation of civil liberties. In fact, I won’t fly with my daughters because of them… an adult knows what they are walking through, but my little girls don’t, they’d just trust daddy not knowing what they were doing.

There, having said that….

How many items something detects when their use is known isn’t always a good measure of their effectiveness. For example, metal detectors rarely detect a gun. It isn’t because they are ineffective, it is beause their value as a deterrent is strong. Remove them because they never find anything, and it wouldn’t be a day before they were needed.

The biggest problem with body scanners is not that they find so few things, because that could be a measure of detterence. The real problem in the math is that the risk they are used to mitigate is far too small for the cost… both in terms of dollars, and in terms of liberties.

For metal detectors, even if they never detect a gun I believe their value as a detterrent alone makes them worthwhile. Body scanners, not even close.


Davi Ottenheimer March 10, 2011 2:55 PM

@ BF Skinner

“with metro rail systems in every major city in the US one has yet to go boom”

Boom, no. Disaster, yes.

BART in San Francisco just the other day failed inside the Transbay (underwater tunnel), shutting it down for the day. It has not been reported by the news but a passenger told me with one train dead, they had to back up other trains behind it in the tunnel, which forced trains above ground to back up. Passengers were taken to the prior station and then left stranded.

Of course, some might say they were lucky to avoid a ride through that tunnel anyway since the tracks are in such disrepair that the noise reaches 100 decibels (jackhammer level).

A similar incident in Anchorage happened last week when the entire train computer monitoring system failed. The ARR representative told me “the big computer gets a glitch every so often and can’t locate any trains, so they all have to stop”. That’s a whole lot of coal and critical infrastructure failure — more than minor problems (pun not intended).

If only a small fraction of the money directed to airport body scanners was spent on tangible rail infrastructure repair and improvement projects…

Rajstennaj Barrabas March 10, 2011 3:22 PM

I’ve spent some time trying to sort out claims of scanner safety:

To summarize, the controversy with backscatter safety stems from calculating the cancer risk instead of measuring it.

Any calculation depends on assumptions, so that if you use different assumptions you have a different model and therefore get different answers.

So for example, the radiation is much less than a dental X-ray, so we assume similarity and so it’s safe.

However for example, the radiation is concentrated in the outer few mm’s of the skin, unlike a dental X-ray, so it’s dangerous.

Neither argument can be decided on the basis of logic, so it comes down to rhetoric and emotion. My model is better than yours, no it’s not, &c.

The correct solution is to have the medical community make medical safety decisions. They have a lot of expertise in doing just that.

Of course, this would prevent a company from getting pork dollars from the government, so instead we calculate the risk and then claim it’s safe.

Rajstennaj Barrabas March 10, 2011 3:37 PM

Apropos colonoscopy (mentioned earlier), the overall risk is 0.3%, not 3% as posted.

And most of the overall risk is taken up by non-serious issues such as discomfort and minor bleeding which resolves of it’s own accord.

The lifetime risk for colon cancer is about 6% and curable if caught, so the risk from having the procedure every 10 years is outweighed by the risk from cancer.

I only learned to make these sorts of risk comparisons by reading Bruce’s writings. I wonder – is there a way to make these sorts of comparisons more publicly known?

Sally March 10, 2011 3:58 PM

@ Rajstennaj Barrabas:

However, you have to realize that you end up dealing with people who overly extend the risk evaluation. “A billion dollars is a small price to pay if we avert Global Thermonuclear War where hundreds of millions of people might die! Think of your children!”

Dirk Praet March 10, 2011 4:12 PM

We can debate the issue of full-body scanners, their constitutionality, their efficiency and their cost as much as we want to, but at least for now it looks like there here to stay. It’s a sad thing.

It would seem to me that over the last decade the USA has become the United Scareds of America rather than the land of the free and the home of the brave. It’s hard to imagine that this is the same nation that liberated Europe from the nazis and won the cold war against the USSR. A country armed to the teeth but terrorised out of its wits by a handful of religious fanatics and buying into whatever lies populist politicians, Soviet-like media and industrial lobbies are feeding them. To the point that they will surrender almost any liberty and freedom as long as it’s disguised as serving “the war on terror”. So-called leaders and sheeple alike who see enemies everywhere except the enemy within. I hardly think I am the only person to believe that the USA has lost its ways and has surrendered its Constitution and the values of its Founding Fathers to fear, profit and greed all in the name of the Almighty Dollar.

I genuinely feel for all honest and good-meaning folks in the US, even for the ill-educated and the misinformed, but at this time I can only quote once more the 1755 statement from the Pennsylvania Assembly in a letter to the Governor: “Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety.” It’s been quoted before on this forum, and by several people, but in the end to me it’s the one phrase that says it all when it comes to full-body scanners.

On a related sidenote: has anyone been doing some digging into how a certain Michael Chertoff is making his money nowadays ? I found the following very enlightning: .

Thunderbird March 10, 2011 4:57 PM

Sally says, “However, you have to realize that you end up dealing with people who overly extend the risk evaluation. ‘A billion dollars is a small price to pay if we avert Global Thermonuclear War where hundreds of millions of people might die! Think of your children!'”

Most of the kinds of things you seem to be describing suffer from two problems: it’s hard to estimate the risk, and it’s hard to estimate the benefit when the outcome is “everyone dies.” Also, I see your example didn’t mention multiplying the benefit by the probability of its applying. If that was the actual problem you were describing, then I agree, except see problem #1.

Richard Steven Hack March 10, 2011 5:57 PM

If all this stuff is so safe, how come every time you get an X-ray, the nurse or technician puts on a protective garment?

I’d say right there someone doesn’t think it’s safe to do that on a daily basis.

I’m also waiting for the inevitable moment when someone figures out how to slip a gun – or several guns – past the scanner through some weird hacker inventive concept.

I remember ex-Navy SEAL Richard Marcinko talking in one of his books, possibly fiction, to a senior officer about how he just flew commercial with brass knucks, knives, a bunch of stuff. This was before 9/11 but I’ll bet he could still figure out a way to do it.

Motivation usually finds a way to trump limited technology.

Dirk Praet March 10, 2011 6:08 PM

@ Richard Steven Hack

Imagine all the stuff Chuck Norris could get on board if he were to turn to the dark side 😎

Wimpie March 10, 2011 10:08 PM

Jake Addams – Discovery

“Considering more Americans die each year from accidents while shaving than from terrorism, if you are really interested in saving lives we could pay for govt. funded barber shops and shaving depots with ER crews on standby for emergencies and still pay less and save more lives than the TSA has.

So with that in mind, I will keep my privacy. Remember when you were in school and studying the USSR and how appalled you were when you learned the Soviet gov. could search anyone at anytime without reason, take you in for “interrogation” at any time without informing family, etc. Lets not get to that point before we decide its gone too far”

Traveller March 10, 2011 11:54 PM

On my last trip, first after the new scanners got deployed, I went through security in two airports. Both times I got to choose which line to wait in, very close to the lines, and it was abundantly clear which lines had advanced imaging scanners and which did not.

This setup makes me wonder – did they decide to intentionally build a system that ensures anybody who cares can avoid opting in for a groping?

I know that, personally, I was expecting a groping. Had I gone through an unpleasant opting out process I would’ve probably been far more motivated to complain and object to my representatives. As it stands, I got to see the TSA and a contractor (one airport was TSA, one not) demonstrate more of the same quality of security theater we have come to expect. I’m annoyed, but not personally violated and my motivation to do something about it has gone down.

Davi Ottenheimer March 11, 2011 1:53 AM

@Dirk Praet “has anyone been doing some digging into how a certain Michael Chertoff is making his money nowadays”

yeah, i have mentioned it before in the comments on this blog. looks like november 2010 was the last time:

“In 2009 Rapiscan paid former Homeland Security Secretary and scanner advocate Michael Chertoff for an ‘advisory’ role.”

that’s partly why i was hoping bruce would be more confrontational with chertoff on the rsa conference panel.

i’d love it if the moderator would ask something like “chertoff is on the scanner company payroll. conflict of interest, yes or no? bruce, you first”

No One March 11, 2011 9:43 AM

I give up. For every person I know that hates the continuing loss of freedoms we endure they have five family members that either don’t care, accept it or request it. And this isn’t even counting the people I know that are already in that group.

I’m glad I decided not to have children long ago so that I don’t have to feel responsible for them growing up in this world.

mcb March 11, 2011 11:18 AM

@ Richard Steven Hack

“If all this stuff is so safe, how come every time you get an X-ray, the nurse or technician puts on a protective garment?

I’d say right there someone doesn’t think it’s safe to do that on a daily basis.”

In fairness, the health hazards are related to a device’s energy level. The nude scanners can see through your clothes, a dental xray can see through your face, and a chest xray can see right through you.

Still, we ought to understand the dose response relationship for aircrews and frequent fliers who have dozens of these nudie pics taken every week.

And it pisses me off that Cherthoff gets to reap the rewards of fearmongering.

Anon March 13, 2011 3:02 PM


Either these scanners can’t see through us and and the energy is concentrated in the skin, or they can see through us and the energy levels are much higher than you realize.

I weigh around 160lb. My skin weighs a lot less. Lower energy. Less mass to absorb it. Plus that compton scattering meaning we have more organic damage.

On the other hand, in some of those scanner pictures I can see folk’s bones…

Look on the bright side, if they catch skin cancer early enough, or cancer of your genitalia early enough, they can cure it via amputation.
Think about that and decide whether air travel is worth it.

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