The Truth About TSA Testing Technology for Radiation

Unfortunately, yesterday’s LA Times story missed the mark and you may have seen a few additional inaccurate stories in the news claiming that TSA was buying equipment to test for radiation exposure. Truth is, we continuously test all of the technology we use and post the results to our website for all to see.

Why the confusion you might ask? TSA routinely puts out Requests for Information (RFI) that are basically market research, asking industry to tell us what else is out there. In this case, TSA put out an RFI to gather information on available tools to continue to monitor our technologies. This is simply designed to ask industry what new technology might be available.

Testing our equipment and exposure to employees is not new. TSA routinely monitors radiation levels to ensure the safety of both passengers and our workforce. We've never found any radiation concerns and the safety reports can be accessed publicly at TSA.gov. TSA made a commitment to post new reports as they're completed to our website so passengers can see for themselves that the machines are meeting safety standards.

Based on all of our previous testing, as well as monitoring from independent sources, we’re confident that all of our equipment meets national safety standards, and is safe for all passengers and our workforce.

As far as another backscatter (body scanner) test is concerned, TSA is committed to working with Congress to explore options for an additional study to further prove these machines are safe. All tests so far, have shown they are well within the national safety standards and each scan is equivalent to the exposure one receives during approximately 2 min of flight.  

Blogger Bob Burns

TSA Blog Team 

If you’d like to comment on an unrelated topic you can do so in our Off Topic Comments post. You can also view our blog post archives or search our blog to find a related topic to comment in. If you have a travel related issue or question that needs an immediate answer, you can contact a Customer Support Manager at the airport you traveled, or will be traveling through by using Talk to TSA.

In Case You Were Wondering, Our Backscatter Imaging Technology Is Still Safe

The safety of our Backscatter Advanced Imaging Technology is being called in to question again. As I’ve done before on this topic, I’m going to simply provide a bulleted list of facts and links. Also, if you haven’t heard yet, TSA Administrator John S. Pistole told Congress last week that we’re going to have another independent safety study on our Backscatter imaging technology.

The Johns Hopkins University Applied Physics Lab (APL) and the Food and Drug Administration (FDA)’s Center of Devices and Radiological Health (CDRH) both verified that the advanced imaging technology (AIT) equipment TSA purchased and deployed emits radiation at rates much lower than the limits set in the national radiation safety standard for all members of the traveling public and all TSA employees.  

The Johns Hopkins University Applied Physics Lab assessment included several recommendations to continue to ensure the highest standard of safety and health. TSA has successfully completed each recommendation.  
A backscatter scan is equivalent to amount of naturally occurring radiation received during two minutes of flying at altitude.  

In addition to these independent studies validating the safety of imaging technology, TSA also conducts site acceptance testing of AIT units upon installation in airports to ensure each individual AIT unit meets safety standards.  Once installed, preventive maintenance is regularly performed by qualified personnel.  

Certified health physicists from the U.S. Army Public Health Command are also performing additional radiation safety surveys to ensure continued compliance with radiation safety standards.  

In early 2011, TSA posted radiation surveys for every backscatter imaging technology unit deployed in U.S. airports. The reports confirm that every backscatter unit currently used for passenger screening in U.S. airports is operating well within applicable national safety standards.  

TSAposts reports for all radiation tests, including the annual TSA-mandated testof every X-ray based technology, on TSA’s website as they are completed.  

Accordingto CBS News, MIT’s leading radiation safety experts and experts from the HealthPhysics Society, drinking three glasses of water a day for a year might giveyou a cumulative exposure of about 0.045 millirems, that's at least five timesmore than the dose from an airport scanner and well beneath the 10,000 milliremline where there is danger. According to Francis Marre, former director ofradiation safety at MIT, “There is no known risk” from being scanned.  

SanFrancisco Weekly story on backscatter technology.  

HealthPhysics Society’s FAQ: “ Safety for Security Screening Using Devices ThatExpose Individuals to Ionizing Radiation.  

FDA FAQ page: “Products for Security Screening of People”.  

SFWeekly article featuring leading radiologists refuting safety claims by UCSFprofessors.  

National standard for one backscatter scan: 0.025 millirem (two and a half one-hundreths of a millirem) per scan.  

TSA’s backscatter systems maximum possible radiation emission: 0.005 millirem (five one-thousandths of a millirem) scan.  

TSA’s backscatter systems actual emission: generally less than 0.0025 millirem (two and a half one-thousandths of a millirem) per scan.  

Advanced imaging technology screening is safe for passengers, including pregnant women and children. One backscatter technology scan produces the same exposure as approximately two minutes of flying on an airplane. Advanced imaging technology is optional for all passengers.

Blogger Bob Burns  

TSA Blog Team

If you’d like to comment on an unrelated topic you can do so in our Off Topic Comments post. You can also view our blog post archives or search our blog to find a related topic to comment in. If you have a travel related issue or question that needs an immediate answer, you can contact a Customer Support Manager at the airport you traveled, or will be traveling through by using Talk to TSA.

 

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Archives of Internal Medicine on TSA Backscatter: “There is no significant threat of radiation from the scans.”

It’s no secret that Advanced Imaging Technology (AIT) has been a hot topic ever since we first wrote about in 2008. While we’ve posted many times on the subject, readers often want to hear from independent third parties to see what their take is. That’s understandable.  So, as we’ve  done in the past, we’re going to highlight another piece on backscatter safety from a third party.

This report comes to you from the Archives of Internal Medicine. In the report, they conclude that there is no significant risk from the radiation emitted during the scans. You can read the full report here:  

Airport Full-Body Screening: What Is the Risk?

Blogger Bob

TSA Blog Team

If you’d like to comment on an unrelated topic you can do so in our Off Topic Comments post. You can also view our blog post archives or search our blog to find a related topic to comment in. If you have a travel related issue or question that needs an immediate answer, you can contact a Customer Support Manager at the airport you traveled, or will be traveling through by using Talk to TSA.

 

TSA Releases Radiation Testing Reports

TSA’s mission of keeping the traveling public safe is carried out at more than 450 airports across the U.S. and its territories. A large part of keeping the public safe includes using the best technology available. Some of the screening technologies use X-ray technology, such as backscatter imaging technology, multi-view advanced technology X-rays, explosive detection systems, and single projection X-ray systems to screen baggage. TSA has implemented stringent safety protocols to ensure the technology used at airports is safe. 

While these machines improve our ability to stay ahead of threats to aviation security,  it’s also important that we’re doing everything we can to ensure our technology is safe for passengers and our officers.

How do we do this? Well, in addition to radiation testing of the machine before it leaves the factory, and again once it is installed at an airport, TSA requires manufacturers and/or third party maintenance providers to test each machine routinely to make sure the radiation emitted falls within applicable standards. Additionally, radiation tests are performed after any maintenance that could impact the X-ray emissions and if the unit is ever relocated from its initial installation position.

By conducting ongoing radiation tests throughout the life of the technology, TSA is going above and beyond regulatory standards to ensure passengers and operators are not being exposed to excessive radiation doses. 

To increase our transparency – and to let you see for yourself that the technology is safe – we will be posting all future radiation reports online. You can see where they’ll be posted here. 

As we prepared to take this step, and to verify our safety procedures, TSA recently selected 15 airports of varying sizes and reviewed reports generated from testing X-ray technologies at these airports over the last two years. You can also find all of those reports here. 

The reports confirm that each piece of technology included in the review operated well-within applicable the national safety standards.

TSA did not alter or edit the reports. Names were redacted to protect privacy and several pages were incorrectly marked as SSI, but other than that, the reports are there, warts and all.

Warts? Well, while looking over these reports, we found some inaccuracies in contractor reporting that affected the documentation of some of the test results.

• Lack of notation for the latest calibration date for the machine being tested or the most recent calibration date noted had expired on survey meters
• Information missing regarding warning labels and other required labels on machines
• Calculation errors not impacting safety
• Missing survey point readings (e.g., If the test procedure required 13 points around the machine to be tested, in some cases, readings for only 11 points were reported)
• Inconsistent responses to survey questions
• No reading of background radiation noted
• Missing other non-measurement related information 

While these inaccuracies didn’t impact the overall assessment that the technology is safe, they are still unacceptable. We took immediate steps to hold contractors accountable and fix the mistakes, and are taking additional measures to build on the robust safety protocols currently in place, by:

• Requiring re-testing of all backscatter advanced imaging technology units in airports, as well as all technology with inaccurate reports, by the end of March 2011;
• Requiring contractors to re-train personnel involved in conducting and overseeing the radiation survey process;
• Requesting the National Institute for Occupational Safety and Health (NIOSH) re-evaluate TSA’s safety program and update its 2008 report;
• Expanding an existing partnership with the U.S. Army Public Health Command to conduct additional independent radiation surveys and radiation safety compliance audits at airports equipped with X-ray based technologies;
• Increasing TSA oversight on the overall radiation survey and documentation process; and
• Ensuring all appropriate contractual remedies are considered and implemented, as necessary, in the event that radiation inspections are incomplete or delinquent.
• Also, every machine using X-ray technology that is deployed in an airport will have a new radiation test conducted within the next 12 months.
• Administrator Pistole has also directed TSA to commission an independent entity to evaluate these protocols.
• To provide additional transparency, TSA is posting all reports currently being conducted – and, as I said above, all future radiation reports – at www.tsa.gov as they’re completed.

To put things in perspective, here are some sources of radiation you may not have been aware of:

• One year of naturally occurring background radiation: 300 millirem 
• Annual recommended limit to the public of radiation from man-made sources: 100 millirem
• Chest X-ray: 10 millirem 
• Flight from New York to Los Angeles: 4 millirem 
• One day of natural background: 0.1 approximately 1 millirem (corrected 3/16/11 20:56)
• Drinking three glasses of water a day for a year: 0.045 millirem
• One backscatter X-ray scan: Approximately 0.005 millirem 

Source: Radiation dose comparisons from the Health Physics Society and other safety experts.

Blogger Bob

TSA Blog Team

If you’d like to comment on an unrelated topic you can do so in our Off Topic Comments post. You can also view our blog post archives or search our blog to find a related topic to comment in. If you have a travel related issue or question that needs an immediate answer, you can contact a Customer Support Manager at the airport you traveled, or will be traveling through by using Talk to TSA.

Facts on TSA X-ray Safety

The Transportation Security Administration (TSA) uses X-ray technology on people and baggage daily in an effort to find items that could cause catastrophic damage to an aircraft. Some are asking how safe this technology is how and how we maintain it to ensure there is no excessive radiation exposure for workers or the traveling public. So, I’d like to use this post to address those questions with facts provided by TSA’s director of occupational safety, health and environment, Jill Segraves. 

·     Before TSA decides to use a new technology, procurement specifications are developed that include requirements to meet the national radiation safety standard. The requirements are validated by manufacturers through third party testing or through testing arranged by TSA, to ensure it meets national safety standards. 

·     After deciding to use new technology that has proven to be safe and meets applicable standards, the manufacturer then will conduct validation tests on each individual unit in the factory during their quality assurance process before the unit is shipped to TSA. 

·     For the carry-on and checked baggage x-ray systems and the general-use backscatter advanced imaging technology equipment, the factory tests, post-installation tests and regular preventive maintenance mentioned above all include radiation safety surveys.  These surveys verify that each unit operates within specifications, is installed correctly and continues operating according to specifications for the life of the unit. When the technology operates as designed, the dose to any member of the general public, system operators, or other employees falls well below the national standard for safety.  

·     The regular preventive maintenance checks, including radiation safety surveys, are performed at least once every 12 months; after any maintenance that affects the radiation shielding, shutter mechanism, or x-ray production components; after any incident that may have damaged the system; after a system is moved or at the request of any employee. 

·     In addition, TSA partnered with the U.S. Army Public Health Command (Provisional) to conduct independent radiation surveys and inspections to confirm the regular testing performed by TSA. Health Physicists from the the U.S. Army Public Health Command (Provisional) perform the surveys and inspections. 

·     The Public Health Command’s Health Physicists also check the indicators, controls, labeling, and observe system operators to ensure proper operating procedures are followed.  The Health Physicists are also gathering area radiation dose data by mounting dosimeters within the inspection zone (that area only occupied by the individual undergoing the screening and delineated by the yellow bordered floor mat) on  certain equipment. 

·     Over the past two years, Health Physicists performed radiation surveys and inspections of 437 carry-on luggage and checked baggage systems at 34 airports during screening operations, and observed system operation and work practices.  The Health Physicists work has thus far confirmed TSA testing that shows all of these systems operating well within safety standards.

·     On top of all these steps, more than 1,100 TSOs at six airports have participated in a mandatory personal radiation dosimetry study over the past year.  The results of both the dosimetry study and other surveys to date reveal that TSA systems are in compliance with safety standards.

On a related note, a study conducted by the National Institute for Occupational Safety and Health (NIOSH) at the Centers for Disease Control just a year after TSA was stood up in the aftermath of 9/11 (between August 2003 and August 2004) has been getting some attention recently. The study came about after TSA requested it when management and other employees expressed concerns about their safety on the job. NIOSH looked at the levels of radiation emissions from Explosives Detection Systems (EDS) and evaluated employee exposure to radiation at airports during baggage screening.

Transportation Security Officers (TSOs) from 12 airports were highly engaged in this study. They chose the airports to include in the study, provided valuable input, and assisted the NIOSH researchers during the on-site surveys. The report was released on October 1, 2008. You can read the report here.  NIOSH made several recommendations that TSA has since implemented.

Some of the information below duplicates some of the information I mentioned previously but I am including it here to show steps taken since the completion of the study in 2004:

·     TSA has implemented key recommendations from NIOSH, including formalizing a comprehensive radiation safety program to meet OSHA and Department of Homeland Security (DHS) requirements and evaluating TSO radiation exposure levels at selected airports through an additional year-long dosimetry study that commenced in April 2009.

·     TSA took additional steps to ensure safe working conditions for our workforce, including:

·     Adding EDS safety training to baggage screening courses;

·     Increasing the number of service technicians equipped with radiation survey meters;

·     Improving maintenance through more stringent maintenance contracts;

·     Working with EDS manufacturers to improve machine design;

·     Providing annual radiation safety awareness training for all TSOs; and

·     Using Safety Action Teams, Collateral Duty Safety Officers (CDSOs), and Employee Councils to improve health and safety communications between employees and management.

·     Consistent with the recommendations of NIOSH, each piece of TSA equipment that uses ionizing radiation undergoes an initial radiation survey upon installation and an annual radiation survey to ensure it stays in top working condition.  In addition, radiation surveys are performed after maintenance on components that affect radiation safety and at the request of employees. This provides a continuous level of safety.

·     Over the past two years, Health Physicists from the U.S. Army Public Health Command (Provisional) performed radiation surveys and inspections of 437 (carry-on luggage and checked baggage systems) at 34 airports during screening operations while items were entering and exiting systems with the leaded curtains constantly in motion.   The Health Physicists also observed system operation and safe work practices.  Over the past year, more than 1,100 TSOs at six airports have participated in a mandatory personal radiation dosimetry study.  The results of both the dosimetry study and surveys to date reveal that TSA systems are in compliance with the Food and Drug Administration’s standard for cabinet x-ray systems emission limits.

This is a lot of information to read through, but after reading, I’m sure you’ll find that TSA is doing its part to ensure the safety of its employees and the traveling public.

Blogger Bob
TSA Blog Team

TSA Myth or Fact: Leaked Images, Handcuffed Hosts, Religious Garb, and More!

There are so many rumors floating around right now that it’s hard to keep them all straight. So, in an effort to get everybody on the same page with the facts, here goes…

Pat-downs Myths & Facts


Myth: All children will receive pat-downs.

Fact: TSA officers are trained to work with parents to ensure a respectful screening process for the entire family, while providing the best possible security for all travelers. Children 12 years old and under who require extra screening will receive a modified pat down. 


Myth: The TSA pat-down is invasive

Fact: Only passengers who alarm a walk through metal detector or AIT machine or opt out of the AIT receive a pat-down. For this reason, it is designed to be thorough in order to detect any potential threats and keep the traveling public safe. Pat-downs are performed by same-gender officers and all passengers have the right to a private screening with a travel companion at any time.


Myth: The pat-down is a punishment for opting out of the AIT.

Fact: There’s nothing punitive about it - it just makes good security sense.  And the weapons and other dangerous and prohibited items we’ve found during pat downs speak to this.


Myth: Everyone who travels will receive a pat-down.

Fact: (Updated 11/23/10 to show percentage) (Updated 3/30/2011 to include random pat-downs) No. In fact, less than 3% of passengers receive pat-downs. Only passengers who alarm a walk through metal detector or AIT machine or opt out of the AIT receive a pat-down. Passengers may also receive a random pat-down. It is one layer in our tool kit to address the nonmetallic explosives threat. In yesterday’s hearing, Administrator Pistole said: “The bottom line is few people in the overall scheme of things will actually receive those pat downs. Now, we've heard some examples, and obviously, there's a vocal group out there who have experienced this for the first time, and, rightfully so, raising concerns, what's behind this. And the bottom line is we, the transportation security officers in particular, are trying to work in partnership with the traveling public to say we want to ensure that you are safe on this flight. Work with us in a partnership to provide the best possible security. And that's what it comes down to.”

Myth: Complaints about the pat-downs are extremely high.

Fact: Only a small percentage of the traveling public receives a pat down as they travel through the security checkpoint.  Approximately 2 million people fly in the United States every day.  The number of complaints is extremely low.


Myth: Pat downs for certain individuals are limited to the head and neck.

Fact: No one is exempt. Everyone is subject to the same screening. TSA is sensitive to religious and cultural needs, but everyone must be screened effectively. Administrator Pistole echoed those sentiments on MSNBC’s Hardball recently.


(At 4:42 on the clip)


MR. SMERCONISH: All right, here's another one that I hear from radio callers, the Muslim guard exception. You may not even know what I'm talking about. But if someone approaches a TSA checkpoint and they're wearing, by way of example, a burka, what's the drill?

MR. PISTOLE: Everybody goes through the same process. So whatever their ethnicity or religious beliefs, which I'm sensitive to and appreciate, the bottom line is people are treated the same in terms of either going through the advanced imaging technology if that's available or to walk through the metal detector. And if they alert, then they would have to have that alert resolved. And the best way of doing that is through a pat-down.

MR. SMERCONISH: No free rides, right, Mr. Pistole?

MR. PISTOLE: That's correct.

AIT Myths & Facts

Myth: AIT is not safe.

Fact: Backscatter technology is safe for all passenger and has been evaluated by the Food and Drug Administration, National Institute for Standards and Technology and Johns Hopkins University Applied Physics Laboratory. All results confirm that the radiation dose is well below the standard for safety set by the American national Standards Institute. The technology is safe. A person receives more radiation naturally each hour than from one screening with a backscatter unit. In fact a traveler is exposed to less radiation from one AIT scan than from 2 minutes of an airline flight. 


Myth: There has been an overwhelming public outcry against AIT.
Fact:  A recent CBS News Poll found that 4 in 5 Support Full-Body Airport Scanners


Myth: AIT cannot detect powdered explosives.
Fact: This is false. Advanced imaging technology is deployed specifically because of its ability to detect both metallic threats – which a metal detector would pick up – and non-metallic threats – which a metal detector would not pick up. This includes explosive material that can take the form of powders, liquids and gels and be used in an improvised explosive device made up completely of non-metallic material.


Myth: Everybody who travels must undergo AIT screening.

Fact: Advanced imaging technology is optional – anybody can choose to opt out and receive alternate screening, which will include a pat down.


Myth: TSA Advanced Imaging Technology (AIT) images can be stored on the AIT machines located in our airports.

Fact: Completely false – TSA’s machines should not be confused with the recent stories about the U.S. Marshals Service.  The machines used by TSA at our airports cannot store, print or transmit images. They simply don’t have that ability. Administrator Pistole also addressed this on Hardball. (At 6:03 on the clip)


Myth: TSA Officers are sharing AIT images they are taking with their cell phones.

Fact: Our officers are prohibited from bringing electronic devices such as cell phones into the AIT viewing room. This is a fireable offense and no such reports have been substantiated.


Myth: The AIT images shared by TSA are proof the images can be stored.

Fact: The images shared by TSA are either from the vendor, or were photographed by the media at a press event where an example of the technology was shown.


Myth: Children must be screened by the AIT.
Fact: Anybody can opt out of AIT, including children.


Miscellaneous Myths & Facts


Myth: Airports can opt-out of TSA screening.

Fact: All commercial airports are regulated by TSA whether the actual screening is performed by TSA or private companies. So TSA’s policies – including advanced imaging technology and pat downs – are in place at all domestic airports.


Myth: Radio Host Meg McLain was handcuffed to a chair after choosing not to undergo AIT screening.

Fact: She was never handcuffed to a chair and many of her outlandish claims were proven to be unfounded.


Blogger Bob
TSA Blog Team
MFZDSEU8AXMY 

White House Blog: Backscatter Back-Story

The Office of Science and Technology Policy (OSTPC) published a post on their White House Blog today offering a detailed description on Advanced Imaging Technology from the Food & Drug Administration and the Department of Homeland Security.

The detailed description was requested by OSTPC’s Director, Dr. John Holdren, after receiving a letter from professors at the University of California-San Francisco seeking more information on the safety of the technology. You can read those letters and the resulting detailed description here: Backscatter Back-Story

Blogger Bob

TSA Blog Team

Advanced Imaging Technology: "Radiation Risk Tiny"

You may have read a recent article stating that Advanced Imaging Technology used at TSA checkpoints is not safe. Because of the discussion the article has created, I wanted to share this with you.

The American College of Radiology posted an article titled: ACR Statement on Airport Full-body Scanners and Radiation and then WebMD followed up with an article titled New Airport Scanners: Radiation Risk Tiny which quoted the ACR article.

From the ACR article: "An airline passenger flying cross-country is exposed to more radiation from the flight than from screening by one of these devices. The National Council on Radiation Protection and Measurement (NCRP) has reported that a traveler would need to experience 100 backscatter scans per year to reach what they classify as a Negligible Individual Dose. The American College of Radiology (ACR) agrees with this conclusion. By these measurements, a traveler would require more than 1,000 such scans in a year to reach the effective dose equal to one standard chest x-ray."

"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."

We also asked the Johns Hopkins University of Applied Physics Laboratory to perform an independent radiation safety engineering assessment of our Advanced Imaging Backscatter Technology and they determined that the radiation dose to scanned individuals from this general use system is within the requirements of ANSI N43.17 2002 and 2009.

In the coming weeks, the FDA will be posting similar information on their web page.

For your reference:

Backscatter technology projects an ionizing X-ray beam over the body surface at high speed. The reflection, or "backscatter," of the beam is detected, digitized and displayed on a monitor. Each full body scan produces less than 10 microrem of emission, the equivalent to the exposure each person receives in about 2 minutes of airplane flight at altitude. It produces an image that resembles a chalk-etching.

Millimeter wave technology bounces harmless electromagnetic waves off of the human body to create a black and white image (not a photograph). It is safe, and the energy emitted by millimeter wave technology is the energy projected by the system is thousands of times less intense than a cell phone transmission. This technology is not new. TSA is not the first to use this technology. It's currently being used in Canadian airports and U.S. courthouses in Colorado and Texas as well as international locations.

This Standard limits the reference effective dose2 delivered to the subject to 0.25 microsieverts (25 microrem) per screening.

For your reading pleasure, here are some documents relevant to security screening of humans using ionizing radiation:

ANSI/HPS N43.17-2009 Radiation Safety for Personnel Security Screening Systems Using X-Ray or Gamma Radiation

NCRP commentary 16, Screening of humans for security purposes using ionizing radiation scanning systems

NCRP Statement 10, Recent Applications of the NCRP Public Dose Limit Recommendation for Ionizing Radiation (2004)

NCRP report no. 116 Limitation of Exposure to Ionizing Radiation (1993) ISBN 0-929600-30-4 recommends annual limits on radiation dose for the general public. Report 116 also introduces the concept of a negligible individual dose.

NCRP report no. 160, Ionizing Radiation Exposure of the Population of the United States (2009)

Screening Individuals with Backscatter X-Ray Systems by Daniel Strom

HPS Position Statement Use of Ionizing Radiation for Security Screening Individuals

HPS Public Information Radiation Exposure During Commercial Airline Flights

American College of Radiology (ACR) Statement on Airport Full-body Scanners and Radiation

EPA.gov Ionizing Radiation

Information on laws and regulations applicable to manufacturers of people screening security systems that use x-rays is on FDA's X-Ray & Particulate Products other than Medical Diagnostic or Cabinet page.

ANSI/HPS N43.17 is not a mandatory standard. More information on the ANSI standards setting process is available on the ANSI website.

The concept of justification based on a societal benefit appears in the International Commission on Radiological Protection (ICRP) report 60 (see paragraph S14).

Random Facts:

For comparison, the energy projected by millimeter wave technology is 10,000 times less than a cell phone transmission.

We, and all objects around us, generate millimeter wave energy - and we are exposed to it every single day.

Backscatter technology uses low level X-ray and a single scan is the equivalent of two minutes of flying on an airplane.

Full Body Scanners at Security Okay by Travelers - When it comes to the newest addition to airport security, 79 percent of travelers said they are comfortable with U.S. airports using full body scanners that can see through clothes.

We've written many posts on Advanced Imaging Technology and you can read them all HERE.

Blogger Bob
TSA Blog Team

Response to: “Oops: Backscatter X-ray machines tear apart DNA"

This article has been receiving quite a bit of attention and it’s leading people to believe the Backscatter Advanced Imaging Technology (AIT) used by TSA emits terahertz radiation. Recent studies are showing that terahertz radiation may “unzip double-stranded DNA, creating bubbles in the double strand that could significantly interfere with processes such as gene expression and DNA replication.”

(I know… who knew that your DNA could be unzipped? Hey buddy, your barn door’s open!!!)

I forwarded the article around to a few subject matter experts here at TSA and was provided with some interesting information:

“TSA has not tested nor procured any terahertz AIT systems.”

That sentence should sum it up for most of our readers, but for those who like to get into the weeds, here is some more interesting information that was given to me from the fine folks at the Office of Security Technology (OST):

The Transportation Security Administration (TSA) has assessed multiple types of AIT systems including X-ray backscatter and millimeter wave. Both offer safe and effective whole body screening for weapons and explosives concealed on a person’s body. Backscatter X-ray technology uses X-rays that penetrate clothing, but not skin, to create an image. Millimeter wave technology uses sensors to collect millimeter wave energy to measure the difference in radiated energy relative to each object against a common background (the human body produces these signatures in typical screening applications) to construct a composite image.

Backscatter - Relies on a narrow, low intensity X-ray beam scanned over the body’s surface at high speed that is reflected back from the body and other objects placed or carried on the body, where it is converted into a computer image of the subject and displayed on a remote monitor. For comparison purposes, the X-ray dose received from the backscatter system is equivalent to the radiation received in two minutes of airplane flight at altitude (0.003* millirem by backscatter (2 scans) compared to .0552 millirem for two minutes of flight). Newer technologies require less scanning time, reducing individual X-ray exposure to .002 millirem for the entire process. The backscatter AIT meets and exceeds the American National Standards Institute (ANSI) standard for personnel security screening systems using X-rays.

Millimeter Wave - Uses non-ionizing radio frequency energy in the millimeter wave spectrum to generate an image based on the energy reflected from the body. The frequency range for millimeter wave technology exists in the range between 30-300 gigahertz. The three-dimensional image of the body is displayed on a remote monitor for analysis. The energy projected by the system is 10,000 times less than a cell phone transmission (.00000597 mW/cm2 for millimeter wave technology compared to 37.5 mW/cm2 for a cellphone).

Other Safety Information

“TSA security screening technologies are required to meet consensus standards, such as those issued by the American National Standards Institute (ANSI), as well as regulatory requirements such as those issued by the Food and Drug Administration (FDA). Our systems are independently tested as well by such laboratories as Johns Hopkins Applied Physics Laboratory (APL) and the National Institute for Standards and Technology (NIST) and FDA. We also apply an aggressive maintenance program to ensure that these systems continue to meet these performance standards. Additionally, TSA Occupational Safety Health and Environment (OSHE) is an active participant in our project integrated project teams. TSA OSHE assists in the development and validation of technology safety requirements. We also conduct safety evaluations as part of our laboratory, TSA Systems Integration Facility (TSIF), operational and site acceptance testing procedures.”

TSA tells its employees, namely Transportation Security Officers (TSOs), about the safety of advanced imaging technology machines, including the radiation exposure, during training on the equipment. In addition, TSA’s Office of Occupational Safety Health and Environment has individuals who work directly with TSOs to communicate safety information about operating the equipment. Information is available to TSOs through the OSHE Web site and employees can contact members of OSHE directly with questions.

*.04 was posted in error. The corrrect number was added. 0.003 millirem. Edited on 1/5/10

Thanks,

Blogger Bob

TSA Blog Team