The fundamental Stuff you Must Learn about Full-Body Scanners [Travel]

What exactly are full body scanners ? What are these health concerns surrounding them? What do you must know? Listed below are the basics.

What are full body scanners ?

Remember the X-ray specs of science fiction comics that may let people see through walls and clothing? Full body scanners are rather like them. The scanners benefit from the undeniable fact that at certain wavelengths, electromagnetic waves can pass through clothes but not in the course of the skin, metal or substances similar to drugs and explosives.

If your eyes were sensitive to these wavelengths like the scanners, every body you meet would appear naked, with pens, coins, belt buckles and so on magically festooned about their person. You might also be capable of see if they were carrying a knife, gun or explosives.

What are the health concerns surrounding them?

There are two main kinds of full body scanner. One uses X-rays while the alternative uses lower-energy millimetre wavelengths . X-rays are hazardous because their photons have enough energy to ionise atoms and break chemical bonds. Which will cause damage to DNA that subsequently ends in cancer. The machines are deemed safe because the entire dose that someone receives during a scan is tiny.

However, earlier this year, a bunch of scientists at the University of California, San Francisco, raised a lot of concerns over X-ray scanners . They said the X-rays they use are low energy to make sure they bounce only off skin as opposed to passing during the body, to supply an image considering objects concealed beneath clothes. Because of this the full dose that the person being scanned receives is focused on the surface instead of spread throughout their body. That can mean the outside receives a dose which is one or two orders of magnitude more than expected.

To many observers, the response of the united states Food and Drug Administration did not properly address these concerns.

Are there health concerns surrounding millimetre-wave scanners?

In theory, these should be safer than X-rays because millimetre photons would not have enough energy to damage chemical bonds. Last year, however, researchers at Los Alamos National Laboratory in New Mexico suggested that these low energy photons could damage DNA in a wholly novel way. They say that while these photons cannot break DNA, they are able to shake it. This shaking could be so strong that it unzips the two strands in DNA, interfering with the genetic machinery that keeps cells working and healthy.

The team at Los Alamos did their calculations for submillimetre or terahertz waves , whose photons are slightly more energetic than those of millimetre waves. Their results are probabilistic instead of deterministic, they say. This explains why some experiments show that terahertz waves can damage DNA while other, practically identical studies show nothing.

While terahertz full body scanners aren’t yet familiar, the work does show that the results of electromagnetic waves on DNA aren’t fully understood.

Are there alternatives to full body scanners?

Travellers can opt out of being scanned and decide to be frisked instead. Within the US, one group is hoping to spotlight the debate over full body scanners by encouraging everyone travelling on 24 November to elect to be frisked .

What about privacy concerns?

The US Transportation Security Administration admits that the scanners be capable of store and print images. However it says this capability is used only when the machines are tested and is switched off at all other times. Critics point out that it really isn’t clear how difficult it is to reactivate this capability or how the TSA prevents employees from recording the photographs with another device comparable to a cellphone camera.

Earlier this week, hundreds of images taken by a body scanner used by marshals at a courthouse in Florida appeared on the net . The TSA says it might be impossible for an analogous leak to occur from airport scanners. It’s fair to assert the public is yet to be reassured.

Photo via TSA

New Scientist reports, explores and interprets the consequences of human endeavour set inside the context of society and culture, providing comprehensive coverage of science and technology news.

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This post is tagged: california san francisco, electromagnetic waves, food and drug administration, orders of magnitude, science fiction comics, university of california san francisco