FAQs: Whole Body Imaging

By Matthew Harwood

The decision by Umar Farouk Abdulmutallab and his terrorist handlers to conceal high explosives in Abdulmutallab's underpants on a Detroit-bound flight on Christmas has led to renewed interest into whole body imaging technology, or full body scans, to detect contraband passengers may smuggle onboard an airplane.

Already, the British, French, Dutch, and Nigerian governments say they will embrace the technology, which allows operators to peer underneath a passenger's clothes and identify hidden threats on their body. The European Union, which overwhelmingly said no to the technology in 2008, is reconsidering its position post-Detroit, reports The Christian Science Monitor. And yesterday, Homeland Security Secretary Janet Napolitano said her department will accelerate the deployment of whole body imaging technology at U.S. airports. There are already about 40 machines deployed at certain airports nationwide, but Napolitano said the Transportation Security Administration (TSA) will fast track at least another 300 units into the field this year.

This increased push for whole body imaging, however, has led to fears that the technology unnecessarily violates passengers' privacy rights and even their health. So what's true and false about whole body imaging technology? Security Management  has scoured publicly available information to answer some of the most pressing questions.

How does whole body imaging technology work?

That depends, because there are two different ways to generate a full body image: millimeter wave technology and backscatter technology.

How do these technologies differ?

Millimeter wave technology beams the passenger with millimeter wave radio frequency (RF) energy from two antennas that spin around the passenger at very fast speeds from head to toe. The energy reflected off the body and other objects generates a three-dimensional image of the passenger's body and anything else carried on his person.

Backscatter technology, however, uses very weak X-rays to generate a two-sided image of a passenger and anything else on that person's body.

Do these technologies identify the same types of threats?

Yes. Manufacturers of each technology say their respective technologies can detect the same types of threats.  L-3 Communications' machines, which use millimeter wave technology,  boast that they can "reveal and pinpoint hidden weapons, explosives, drugs and other contraband."

RapiScan, which uses backscatter technology, states that its machines screen passengers "for a wide range of potential threats including liquids, contraband, ceramics, explosives, narcotics, concealed currency and weapons." American Science and Engineering (AS&E), another manufacturer of backscatter technology, says its system "displays both organic and inorganic materials, revealing objects such as guns and knives, liquid and plastic explosives, composite weapons, and other hidden threats and contraband."

On its Web page devoted to whole body imaging, the TSA makes no distinction between the types of threats each technology can detect.

Are these technologies safe?

The consensus seems to be yes. The American College of Radiology (ACR) recently released a statement vouching for the safety of each type of technology. "The ACR is not aware of any evidence that either of the scanning technologies that the TSA is considering would present significant biological effects for passengers screened."

But there is a difference between the two types of technology. Backscatter technology exposes passengers to ionizing radiation, much like medical X-rays, while millimeter wave technology does not, reports Reuters. Instead, millimeter wave technology "uses radio signals akin to cell phone RF energy," reports "Since the millimeter waves are low-level radio waves, the radiation is non-ionizing and so it is considered completely safe."

Despite this, the X-ray dose used by backscatter machines is extremely low. Dr. James Thrall, chair of the ACR and chair of radiology at Massachusetts General Hospital in Boston, told that a passenger "would have to take hundreds and hundreds of trips requiring screening to even reach what would be considered a negligible dose."

On their Websites, both RapiScan and AS&E address radiation fears explaining that a passenger will receive considerably higher radiation doses once they've been flying for an hour or two than they will undergoing screening with backscatter technology.

Nevertheless, L-3 Communications, which manufactures millimeter wave scanning technology, states that its machines screen people "without exposure to harmful electromagnetic radiation."

Are privacy concerns legitimate?

Yes and no. Both whole body imaging technologies display anatomically correct images of the person screened, which is why some civil libertarians liken this screening to "virtual strip searches." The ACLU yesterday released a new backgrounder on the technology yesterday, stating it "reveals not only our private body parts, but also intimate medical details like colostomy bags. Many people who wear adult diapers feel they will be humiliated."

The TSA as well as the manufactureres of the technology say they have taken many steps to protect the identity of the passenger being screened. AS&E's backscatter technology can be privacy-enhanced, according to the company. When the image is generated, it looks like a chalk outline of the passenger which also "outlines any potential threats on the person -- similar to when a child traces an outline of his/her hand" without "revealing images of the body." The machines that use millimeter wave technology produces an image that looks like a photo negative, but the faces of passengers are blurred, according to the TSA.

The agency also says it has  implemented privacy protections into the screening process when using this technology.

When a passenger is screened, the TSA officer that assists the passenger never sees the image. The TSA officer that views the image is in a remote, secured viewing room, ensuring she never sees the passenger's face. The two officers communicate via headset. Once the remotely located TSA officer looks over the image and verifies that the passenger has no contraband, she signals to the TSA officer assisting the passenger to let the passenger continue on through security.

As another safeguard, the ability of the machines to store, print, transmit, or save the image is disabled before the machines are delivered to airports. TSA officers are further barred from bringing cameras, cell phones, or photo-enabled devices into the viewing room as one more privacy protection. 

(Assistant Editor Joseph Straw also discussed whole body imaging in the Sept. 2008 feature "New Views on Airport Screening.")

♦ Photos of whole body images by TSA


Failed Bomber and the Use of Whole Body Imaging January 7, 2010


Now that the Administration has fully engaged in evaluating the systems failures, which allowed Umar Farouk Abdulmutallab, a Nigerian Islamic terrorist, to board a US airliner with a bomb concealed in his underwear, I feel compelled to contribute my insight.

Based on 33 years flying large transport aircraft worldwide for both the US Air Force and a major US airline and concurrently being an aviation security and operations expert, I see the return of many old issues.  Following 9/11, the nation came together supporting the concept that intelligence data had not been proactively shared to allow government agencies to meet the threat arrayed against us.

As an established AvSec specialist from well before 9/11, I articulated widely that not only had the intelligence not been shared between government agencies but also with the private sector operators.  Had I and my professional colleagues been consulted by the FBI on the data they had acquired, an understanding of airliner flying lessons without the proper background and focused on only flying not landing could only point to one conclusion.

Now an even more prominent indicator and warning has been ignored.  In the hilarious 1980 movie Airplane, outlandish aspects and innuendos of airline industry were the satirized. In one vignette responding to the Arabic hijackers of the late 1970s, a young Arabic man is handed his boarding pass as the agent recites his travel data: “one-way ticket, cash, no luggage – here is your ticket Mr.….” In 1980, that was funny; 30 years later it is a sad commentary that both the public and private sector still cannot learn from historic facts.

Next, the universal hew and cry for better technology to find bad things carried by passengers. Items carried by law-abiding people do not automatically make them homicidal. In fact, the 9/11 terrorists did not carry any prohibited items onto the airplanes other then their intent to commit atrocities. Things and items do not kill people, in this case – people kill people.

The focus of our 21st century technology efforts will be better aligned when targeted on detecting questionable people first then ascertaining if bad things are also involved. This does not include profiling racial, religious or ethnic appearances; rather the detection of behavioral traits, and/or analysis of data, which indicates a need for closer surveillance, examination and investigation of individuals.  The basic premise is that people who are about to commit a crime will behave differently than someone going for an airplane ride; especially in the case of suicide bombers as they have not previously practiced their crime.

This leaves us with applying technology, behavioral science and intelligence analysis to vet the traveling public. Many travelers today are military members, government employees or federally elected officials who carry US government security clearances well exceeding that of the screeners at the airport.

Most of these folks already have biometric credentials and given proper equipment to read them will positively establish their identity.  These known travelers could be directed into a screening-lite line for a much quicker and efficient process.  A second group would likely be comprised of the great majority of travelers of whom considerable information is already contained in the reservations computer even if they only travel occasionally.  This group gets the current standard screening procedure to include secondary screening should questions be raised.  Finally, there will be a small group of whom little is known, points of origin or destination, payment methods, behavioral triggers tripped, or newly integrated watchlist flags.  These people need to be thoroughly evaluated, and this is where the best technology comes into play.

Whole Body Imaging (WBI) currently in use and development uses either of two different technologies. Backscatter Passenger Imaging uses low intensity X-ray technology to show items in pockets or concealed on the person. Millimeter Wave Technology involves projecting radio frequency energy over the passenger’s body creating a 3-D image and revealing the smallest concealed item. The images from both systems are rendered unrecognizable, and we certainly have the ability to prevent misuse of the equipment. Indeed both systems have security blocks built in that prevent the recording or storage of an image.

I agree with the President’s remarks of yesterday: “we have to do better, we will do better, and we have to do it quickly. American lives are on the line.”

There are aviation security professionals like myself with many years of operational experience. When this expertise is synergized with government intelligence analysts and airline operators, we will find that the sum of the parts truly exceeds that of the individual parts taken separately.

“Private sector preparedness is not a luxury; it is a cost of doing business in the post-9/11 world. It is ignored at a tremendous potential cost in lives, money, and in national security.” - 9/11 Commission Final Report

Kevin McCarthy
MoonRaker Associates
202.536.9347 mobile
Washington DC ~ Park City UT

By designed neither the

By designed neither the backscatter (x-ray) or the MMW penetrate deeper than the very top layer of skin. They can be bested by simply placing the contraband under the breast, between the buttocks, between fat folds or in an orifice.

These devices are too easily beaten for the amount of money spent and degree of privacy that is lost. A better alternative would be effective explosive detectors or explosive detection dogs.

There is no need for anyone to see your privates in order to board a plane.


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