Journalism in the Public Interest

Just How Good Are the TSA’s Body Scanners?

While the Transportation Security Administration says that airport body scanners are highly effective at detecting explosives hidden underneath clothing, some studies and a congressman briefed on classified research suggest the machines could miss carefully concealed plastic explosives.

A man stands in a body scanner as others place their luggage through the security screener at Baltimore Washington International. (Jim Watson/AFP/Getty Images)

It was the end of a four-hour congressional hearing, and Florida Rep. John Mica was fuming at Transportation Security Administration officials.

The TSA had begun deploying hundreds of body scanners to prevent suicide bombers from smuggling explosives onto planes. But Mica, the Republican chairman of the House Transportation Committee, had asked the Government Accountability Office to test the machines. The results, he said, showed the equipment is "badly flawed" and "can be subverted."

"I've had it tested, and to me it's not acceptable," Mica said at the hearing earlier this year. "If we could reveal the failure rate, the American public would be outraged."

Mica's comments received almost no press coverage. But his outrage, together with other reports by government inspectors and outside researchers, raise the disturbing possibility that body scanners are performing far less well than the TSA contends.

The issue is difficult to assess since the government classifies the detection rates of the devices, saying it doesn't want to give terrorists a sense of their chances of beating the system.

But the evidence is mounting.

Just last week, Department of Homeland Security investigators reported that they had "identified vulnerabilities" in the scanners' detection capability, though the specifics remain classified. Previous research cast doubt on whether the scanners, which are designed to see underneath clothing, would detect a carefully concealed plastic explosive like the one used by the underwear bomber on Christmas Day 2009. One study suggests the $170,000 scanners would likely miss some explosives that could be found during a pat-down.

And recently, Mica and other members of Congress were briefed by the GAO on the full findings of its covert tests. The results, Mica told ProPublica, are "embarrassing."

Other lawmakers who have also been briefed declined to comment.

How effective the machines are at thwarting terrorism is critical for evaluating whether the TSA is making airline passengers more secure or wasting taxpayers' money -- and possibly jeopardizing their safety. Research shows that one type of scanner, which uses X-rays, could slightly increase the number of cancer cases. The other scanner, using millimeter waves, has been hampered by false alarms caused by folds in clothing and even sweat.

The TSA says the body scanners are the best technology available and an improvement by leaps and bounds over the metal detectors, which cannot detect explosives or other nonmetallic weapons.

The agency says its body scanners have found more than 300 dangerous or illicit items -- everything from a loaded .380-caliber Ruger handgun to exotic snakes that a man tried to smuggle inside his pants.

Last month, TSA administrator John Pistole boasted to Congress that a scanner had picked up a piece of Nicorette gum. And in Buffalo recently, a passenger who was caught with a ceramic knife after a pat-down admitted that he had opted out of the scanner because he figured it would find the knife.

Although the TSA's machines have yet to find an explosive, screeners frequently come across bottles of alcohol and drugs, which could easily have been a powder or liquid explosive, spokesman Greg Soule said.

Two homeland security officials, who asked not be identified speaking about vulnerabilities, said recent intelligence that terrorists are considering implanting explosives inside their bodies shows that the scanners are forcing would-be suicide bombers to adapt their methods. The body scanners see only underneath clothing, not inside the body. Carrying out an attack with an implanted weapon, the officials said, would be technically more difficult than if an attacker had a bomb strapped to their chest.

The GAO reported in 2010, however, that it was "unclear" if the scanners would have caught the explosive PETN that underwear bomber Umar Farouk Abdulmutallab tried to detonate on a Northwest Airlines flight over Detroit.

After the failed attempt, the TSA ramped up its deployment of two types of body scanners -- one using backscatter X-rays and another using low-powered electromagnetic waves, known as millimeter waves. The TSA says both are highly effective, but a small number of studies that have been released publicly raise questions about each machine's ability to detect explosives.

Last year, Leon Kaufman and Joe Carlson, two physicists at the University of California, San Francisco, simulated what the backscatter X-ray scanners might see if a passenger carefully molded explosives to blend in with the human body. The machines were effective for seeing metal objects hidden on the human body and could detect the hard edges of organic materials, such as a brick of explosives, according to the study published last year in the Journal of Transportation Security.

But a thin, irregularly-shaped pancake taped to the abdomen would be invisible in images because it would be easily confused with normal anatomy, Kaufman and Carlson wrote. "Thus, a third of a kilo of PETN, easily picked up in a competent pat-down, would be missed by backscatter 'high technology,'" they concluded.

"The amount of contrast between an explosive and tissue is very, very low and not in the range where someone viewing the images could discriminate it by eye," Carlson said in an interview.

Peter Kant of Rapiscan Systems, which makes the backscatter machine, declined to comment on the researchers' study but said the scanner "has exceeded all aviation security detection testing globally."

No recent study of the millimeter-wave machine, manufactured by L-3 Communications, could be found. But initial tests at Seattle-Tacoma International Airport in 1996 showed a detection rate of 73 percent.

Bulk plastic explosives were the hardest threat to detect, according to the study by researchers at the Pacific Northwest National Laboratory. Screeners who were new to the machine found nearly all the Glock pistols in the images, but they were able to identify the bulk explosives only 56 percent of the time.

Another study a few years later tested a primitive version of the privacy software now used in airports in which detection is performed by a computer, not a person. The detection rate was comparable, the researchers concluded, but the test did not break down the results by type of threat.

"Certain objects are tougher to find than others," said Tom Ripp, president of L-3's security and detection division. "I would think that both technologies have the capability to find these threats. Is it easy to find these threats? I would not say it's easy to find these threats. But they can be detected."

Prompted by an outcry over the graphic images the body scanners produce, the TSA began installing privacy software on all of its millimeter-wave machines this summer. Instead of creating an image of the passenger's body, the machines now display a generic outline of a human body with potential threats highlighted by yellow boxes.

"The TSA has said that automated detection had to be as good as or better than the required detection by an operator," said Bill Frain, a senior vice president at L-3. "Right now, we're on par."

The X-ray body scanner, however, still produces images of passengers' bodies, which are examined by TSA screeners in a separate room. Rapiscan has developed an automated system, but it is undergoing tests in TSA research labs.

Before such software was developed, many security and imaging experts believed the backscatter X-ray machine produced sharper images than the millimeter-wave machine. Millimeter waves have longer wavelengths than X-rays, resulting in a lower resolution.

But with automated detection software, the machines would no longer produce images, and the ability of the machines to detect threats is more dependent on the algorithms used in the software.

The TSA has spent more than $100 million on the body scanners and plans to spend hundreds of millions of dollars more as it outfits nearly every airport security lane with a scanner by 2014.

Malcolm McLean

Dec. 22, 2011, 11:10 a.m.

If the scanners cannot detect PETN - the most commonly uused ingredient in a home made or lab made personal bomb - then they are virtually worthless.

I have been through these scanners and as a non celebrity - I have very little concern that my x-ray like picture is going to hit youtube or the internet.

However I see a TMZ / Trashy tabloid paying big bucks for a scan picture of a celebrity revealing everything - or close to it is an obvious security risk - or embarrassing at least.

Implant Science Corporation has the answer and TSA is testing their technology, even as we speak.

The TSA will come thru with flying colors!

Unfortunately the TSA has dragged its feet on certifying new techn ology that would eliminate all of the concerns stated above.  Implant Sciences has a scanner that does not use radiation, detects explosives including PETN and does not reguire agents to physically touch passengers…..Unfortunately this technolgy has been stuck in the the slow process of governement approval and certification.. The EU has just recently certified the technolgy for use in airports throughout the EU…when will the TSA get a clue!

Lies, lies, and MORE lies!  This Country was built on war and certain VIPs continue to profit from war.  The “war on terror” is no different.  “Terror” is an act, not a physical entity.  Declaring war on an act is insane, unless you want to make money.  How do you make money?  Ask John Kerry and others in Congress, who approve the government contracts with these companies (scanner company trades as LLL on market) and buy large amounts of stock of the same companies!  It’s called “insider trading”, if you or I did it we would serve time, but it’s completely legal for Congress to make these transactions.  Now, outside of that, name any “potential act of terror” that was stopped by TSA.  None.  All of the attempts since 9-11 were thwarted by patriotic Americans (shoe bomber, underwear bomber, Times Square bomber) and police work.  So why continue to dump billions of tax payer dollars into an inept government program, rather than sending tax reimbursement checks out to help with economic stimulus?  It’s just too profitable.  Have fun airport shopping while TSA violates the 4th Amendment and feels up your grandma and children!

The TSA will have some good news to proclaim in the near future.

We will be protected in a gentle way.

Implant Science Corp. technology will give the TSA a wall of respectability.

Why worry about explosives? 
Evidently if I don’t turn off my cell phone, I can bring the plane down! 
Even though the cell signals are going thru the airwaves all the time.

But according to USA Today, it is a hazard.  IMHO, I question this assertion.

Stephanie Palmer

Dec. 22, 2011, 5:20 p.m.

I guess this is just another reason the Homeland Security wants so much money.  What Homeland Security should protect us from is Congress.

Just this past Saturday I accidentally made it through Boston Logan security with the following in my bag:
- half full bicycle water bottle
- scissors
- pocket full of change
- hair paste
- gel lip gloss

Go get ‘em TSA.

What is worrisome is that TSA has been so adamant about refusing to allow independent testing. What are they afraid this will reveal?

And more importantly, why is TSA so willing to sacrifice passenger privacy and put their health at risk in order to protect private manufacturers’ products and their profits?

There is clearly an implication of corruption in the deployment of the scanners which demands further investigation by Congress

They are no good but keep them for show and inactive, there to scare criminal minded guys and only activate when someone from a supicious background e.g. Lebanon, Palestinian, Srilankan etc. shows up at the airport. By the globally developed electronic signatures in a simple passport of any of the global citizens we can track down each traveller and new honestly explained laws made for public safety will not require everyone to pass through the scanners. Also private guns from the global streets will be taken away and the process of changing laws can be started with guys like Mr. Barack Obama and his less greedy advisers -who are not connected with Oil and Weapon businesses.

Walter D. Shutter, Jr.

Dec. 23, 2011, 7:11 a.m.

An amusing story that illustrates what happens when increasing/evolving security measures meet the Law of Diminishing Returns.
By the way, terrorists are way beyond “contemplating” implanting explosives in their own bodies.  A couple of years ago, a Saudi terrorist gained an audience with a Saudi Prince who was a counter terrorist official.  Prior to the audience, the terrorist had shoved a plastic explosive charge and cell phone linked detenator up his butt. The subsequent explosion wounded the Saudi Prince, shredded the terrorist, and severely degraded the room’s decor.
If this catches on, instead of purchasing expensive new scanning machines of dubious reliability, the TSA would be well served by hiring screeners with long fingers.

The paradigm promoted by this article is that better, more invasive, scanning technology is the answer to our security needs.  It is based on the concept that we would be safer if the machines worked better.  Why is this believed?

I am amazed that, especially in the United States, there is not a public outcry and mass refusal to submit to scanners and body searches. These are not the values that I learned in school in New England—What would Emerson and Thoreau have told us?

Have we forgotten that the excuse used to install these scanners was the so-called “underwear bomber”?  He was allowed to board an aircraft due to failure of established security protocols.  Had these protocols been followed, he would never have gotten on the plane.  Effective profiling is the answer.  People should be searched because they are suspicious.  Simple profiling could reduce the number of searches by 99 percent, and the remaining searches could be conducted thoroughly.

Here’s a test for those who have trouble with the profiling concept.  Should a grandmother with proof of US citizenship, a roundtrip ticket, traveling with gifts and luggage and two grandchildren from her city of residence to the city of residence of her grandchildren by subject to search and a body scan? (Hint: the answer is “No—no threat found”).  Now imagine that a security expert could define rules to screen 99 percent of the population.

The scanning and searching of passengers, including grandmothers and small children, is about compliance, NOT security.  This assertion is easily proven by any act of resistance, such as demanding your rights as a citizen.  Your resistance is taken as a reason to escalate—no other evidence is needed. 

It is the biggest loss of liberty I have seen in my life time.

In the meantime, baggage handlers continue to go unscreened & “free” to steal articles from unlocked (by TSA orders) luggage and to smuggle drugs in baggage.  A number of them were caught not long ago.

If they can put drugs in luggage, they can put bombs on board too.

And is the cargo being sent on planes that also carry passengers being sent through these highly touted scanners too?

If not, what is the POINT?  If equivalent security measures aren’t being applied to baggage handlers and anyone else who can place dangerous items on commercial (or private) airplanes, or for that matter, large private planes (whose pilots & passengers go through NO security), and cargo being loaded onto commercial passenger planes isn’t being screened, then current TSA procedures seem like nothing more then getting passengers used to being treated like criminals (w/out benefit of a trial).

So, does Chernoff work at/is a CEO of the corporations that manufacture/hold a patent on any of these supposedly superior machines?

The giant-butt Zulus manning and womanning the machines could not otherwise get a job if their life depended on it - they are subnormal for the most part.
Well, Americans, enjoy the continued expansion of the Feral Federals…\\

Tom:  Unfortunately, even Al Quaida are using grandmothers and small children to carry their bombs, so your analogy is not such a good one!  I don’t think you can accurately profile someone who might or might not be a terrorist.  Once you figure out a way to round them up, the terrorist organization finds a way around it.  It will be a non-ending problem with no solution in sight.  The scanners are useless, x-rays are dangerous, and pat downs are demeaning.  Where do we go from here?  My solution—don’t fly unless you absolutely have to.

What’s up with IMSC?
The following is a statement taken directly from the US House of Representatives Joint Majority Staff report dated November 16, 2011…..“The TSA has a vital and important mission, critical to the security of the traveling public. It is the Government’s responsibility, however, to DIRECT THE AGENCIES MISSION AND PREVENT CUMBERSOME BUREAUCRACY FROM INHIBITING THE TSA’S ABILITY TO ADDRESS AND ADAPT TO CHANGING SECURITY NEEDS”
It could’nt be any clearer that Congress is spearheading the campaign to adopt widespread Explosive Trace Technology in our nation. What some may not realize is that our product is the best and probably the only solution for their needs and mandate. The reasons are as follows:

>RADIOACTIVE SOURCE…..Implant Science’s B220 product is the only product that does not have a radioactive source. Our competitors Morpho and Smiths Detection products contain a radioactive source. The European Union has banned products containing radiation. Considering the uproar in the US about the radiation in the scanners, it is very doubtful that the TDA would adopt another product for use that contained radiation.

>CLEAR DOWN TIME…..Implant Sciences B220 clears down in a matter of seconds. While Smith Detection’s and Morpho"s ETD products seem to come close to the clear down time, this is just a small part of the entire picture.

>DECONTAMINATION…..The Implant Science’s B220 is the ONLY product that decontaminates itself. Smiths Detection and Morpho do not have the proprietary technology to decontaminate itself. Their product can take hours or even days to do this. The TSA related this information to Glen. This is very important because unless the machine is decontaminated fully after each use, the next person in line to be checked will be shown to have the same results as the previous person. It is easy to see how there would be the possibility of false positives or false negatives. This is definitely not a good position to be in when using the competitors products.

>CALIBRATION…..The Implant Sciences B220 calibrates itself. The Morpho and Smith Detection products take human beings and machines to calibrate. This is a waste of man hours and could necessitate the hiring of more personnel. If you remember one of the RFP’s that the Dept. of Homeland Security issued mentioned that the product would not require the hiring of additional TSA employees.

>LOW COST OF CONSUMABLES….. The average cost of consumables for each of our competitor’s technology, per machine, is estimated to be $10,000 a year. Our cost of consumables for the B220 is estimated at less than $1,000 a year per machine. The calibration traps ,ALONE, for the Morpho product cost $1 each. Multiply that by each passenger that would be screened by the product in a years time and you can see why the cost of consumables using their product adds up fast. Considering the amount of waste that was documented by Congress, It would be an excellent bet that the TSA would not want Congress to report this waste in their next report.

Implant Sciences Corp.

This article is part of an ongoing investigation:
Body Scanners

Body Scanners: Risking Health to Secure Airports

In an effort to detect explosives hidden under clothing, is the TSA jeopardizing passenger safety?

The Story So Far

The Transportation Security Administration is planning to roll out body scanners at nearly every airport security lane in the country by 2014. Right now, it has deployed more than 500, split about evenly between two technologies—one using X-rays and another using radio frequency waves.

Several prominent radiation safety experts have raised concerns about exposing millions of airline passengers to X-rays.

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