Full body "X-rays"

[nlagalle]

Australian airport trials full-body X-rays | NEWS.com.au

A TRIAL of new security scanners that will subject travellers to a "virtual strip search" will start at Australian airports this month.

Interesting.... Has anyone else heard of this? I saw it on another forum. here is what it might look like:

http://www.tsa.gov/blog/uploaded_images/TSA-Release-Images-2-050808-726403.jpg

 

[v8Statesman]

I am not sure I would like to be subjected to ionising radiation evertime I needed to fly. It is bad enough that you get it at high altitude, This is just adding more free radicals to the body, larger instances of cancer to follow.

 

[Will]

I don't think this is anything to be concerned about.
It is claimed to have "1/10000" the radiation of a "medical x-ray"; if they mean a chest x-ray, that means it only gives you 25 seconds worth of background radiation. Negligible compared to flying, or, indeed, living for one minute.

 

[docjames]

mrsdoc inadvertantly had one of these at JFK last month.

Security "selected" her for extra screening and directed her into this. Being the good Aussie, she went along with it, then realised afterwards what it was. There was a sign afterwards (!) saying it was not complusory and a pat down could happen instead. So regular travellers be aware you can refuse.

Also, the passengers being selected for "random extra screening" were all carrying foreign passports (i know b/c you carry your PP and BP through the usual scanner). Seems they stuill cant believe anyone with a US passport is a threat, and everyone else is. Doesnt sound very random to me.

 

[medhead]

I don't think this is anything to be concerned about.
It is claimed to have "1/10000" the radiation of a "medical x-ray"; if they mean a chest x-ray, that means it only gives you 25 seconds worth of background radiation. Negligible compared to flying, or, indeed, living for one minute.

Funny comparison - 25 seconds of background. Do you have a source for this 1/10000 of a medical x-ray. A medical x-ray can mean many things, from a plain hand x-ray all the way to a whole body CT. These have vastly different radiation exposures.

In real radiation dose terms I've heard that these machines are in the order of micro Sieverts (uSv). Average background radiation is about 1.5 milli Sieverts (mSv) in Australia. So micro Sv would be some small fraction of average background. There is also plenty of evidence to suggest that below about 100 mSv the effect of radiation is not harmful and may be beneficial. This is also supported in part by the most recent international recommendations on safe use of ionising radiation. This research also suggests that the rate of exposure is much more important to determine the harm. So getting a year of background in 10 minutes might be more harmful then getting that background radiation over 1 year.

However, those recommendations also have a fundamental system of radiation protection that includes the principle of justification. They also maintain the use of a theory that says any radiation exposure increases risk. Therefore any use of ionising radiation must justify the increased risk associated with the exposure against the benefit that will arise from that use of radiation. These security scanners just ahven't done that at all.

They did initially approach state government regulators and most of them told them to justify the use of these machines. However, now they are been trialled at airports under Commonwealth control. It would seem that somehow the state governments have been bypassed on these x-ray machines.

 

[Hvr]

Let me walk through and they would gouge their eyes out.

Not a pretty sight at all.

 

[Will]

Funny comparison - 25 seconds of background. Do you have a source for this 1/10000 of a medical x-ray. A medical x-ray can mean many things, from a plain hand x-ray all the way to a whole body CT. These have vastly different radiation exposures.

In real radiation dose terms I've heard that these machines are in the order of micro Sieverts (uSv). Average background radiation is about 1.5 milli Sieverts (mSv) in Australia.

Have been scouring the net to try to find that figure again, but can't. Maybe I misremembered through the red wine fog of last night?

However, from the TSA:

the CastScope emits less than 10 microRem of radiation per scan and a typical medical X-ray emits 10,000 to 100,000 microRem per scan. Q: How much radiation exposure is produced from 1 scan of the CastScope? Is it safe?
A: One scan is equivalent to approximately 10 microRem of radiation. This is equivalent to the exposure each person receives in about two minutes of airplane flight at altitude or each person receives every 15 minutes from naturally occurring background radiation.

100 Rem = 1 Sv
One scan = 10^-5 Rem = 1^-7 Sv = .1 µSv = 100 nSv

I think the original points stands, vis the radiation dose is on a different order of magnitude to anything medical.

ie:
1 security scan is about 0.0001 mSv
1 Chest X-Ray is about 0.4 mSv. (or 4000 scans)
1 CT Chest is about 8.3 mSv. (or 83000 scans)


ps what does it say about the TSA that they continue to use an archaic unit (the Rem) whose use is 'strongly discouraged' by the NIST?

 

[medhead]

I think the original points stands, vis the radiation dose is on a different order of magnitude to anything medical.

ps what does it say about the TSA that they continue to use an archaic unit (the Rem) whose use is 'strongly discouraged' by the NIST?

I certainly can't disagree that the dose is rather trival. My issue is that the introduction in Australia goes against one of the fundamental principles of radiation protection, possibly with the agreement of officials who would doggedly stick to the linear no threshold (LNT) hypothesis. And LNT says all dose no matter how small is potentially harmful. There is a certain disconnection between supporting LNT and agreeing to exposing 1000s to a "trival" radiation dose.

As for the continued use of the rem by TSA - that just shows they are typical north americans .
BTW the rem is still a legal unit is Oz as well (well it was about 5 years ago)

 

[NM]

I think the original points stands, vis the radiation dose is on a different order of magnitude to anything medical.

ie:
1 security scan is about 0.0001 mSv
1 Chest X-Ray is about 0.4 mSv. (or 4000 scans)
1 CT Chest is about 8.3 mSv. (or 83000 scans)

How about 2 head CT scans as I had yesterday?

 

[Will]

How about 2 head CT scans as I had yesterday?

Two?! Did you knock it? Hope you're alright.

They're about 2 each, depending on the age of the scanner.

 

[NM]

Two?! Did you knock it? Hope you're alright.

They're about 2 each, depending on the age of the scanner.

After the first they decided they needed to inject some dye to show up the blood vessels better, so had to do a second. Now awaiting the results. But its good to know I can have a few thousand airport scans and still be less than today's radiation exposure.

 

[Will]

Sorry to hear that

Hope they didn't find any problems.

 

[NM]

Sorry to hear that

Hope they didn't find any problems.

Thanks. Dunno yet. I find out on Friday along with this morning's echocardiogram results. I do know the Carotid Doppler ultrasound this afternoon was all clear.

 

[ethernet]

In another misleading Statement X-Ray Full body see through scanners are being 'Trialled' with a press release claiming 1/400th dose of an X Ray.
These are high energy, ionising radiation - Link http://http://en.wikipedia.org/wiki/Non-ionizing_radiationhttp://en.wikipedia.org/wiki/Ionizing_radiation

Principle 1: Do not believe the manufacturer - measure the damn things!
It is called back scatter - where like an exploding can of paint, everyone close by will cop a 'splash'.

I digress, but having a dozen exposure 'Tags' about the scanning area would be a prudent safety measure for the OH&S people to DEMAND.

But never mind, the bag scanners, when a flap lifts up due to irregular shaped items, also hits you with a dose. You can feel good about this, because the security attendants will cop the most. Health fear over new airport scanners | Mail Online

The backscatter machines use high-energy X-rays that are more likely to scatter than penetrate materials as compared to lower-energy X-rays used in medical applications. Although this type of X-ray is said to be harmless, it can move through other materials, such as clothing. When being screened, a passenger is scanned by high-energy X-ray beam moving rapidly over her body. The signal strength of detected backscattered X-rays from a known position then allows a highly realistic image to be reconstructed. In the case of airline-passenger screening, the image is of the traveler's nude form. The image resolution of the technology is high, so the picture of the body presented to screeners is detailed enough to show genitalia. These images are not necessarily temporary - screeners can save the body images to the system's hard disk or floppy disk for subsequent viewing on either "the system monitor or on any IBM compatible personal computer with color graphics."

The machines are referred to as 'low-dose', but there is a school of thought that there is no 'safe' radiation dose," said Dr Burnett, who has had 15 years' experience working in the NHS.

Anyway, if you fly a lot, consume lobster, smoke, and live on rocky ground and plan to move to the Isle of Man (tax Haven)
http://www.gov.im/lib/docs/dlge/enviro/govlabs/radmon07.pdf - not good.

 

[medhead]

In another misleading Statement X-Ray Full body see through scanners are being 'Trialled' with a press release claiming 1/400th dose of an X Ray.
These are high energy, ionising radiation - Link http://en.wikipedia.org/wiki/Ionizing_radiation

Principle 1: Do not believe the manufacturer - measure the damn things!
It is called back scatter - where like an exploding can of paint, everyone close by will cop a 'splash'.

What? first off you've given a link to explain one type of radiation. That tells us nothing about how these machines operate. Second, the type of image they produce means the x-rays can only be pentrating the clothes not the body. If an intense beam passed into the body and onto the image sensor then the image would be showing bones not just the outside of the body.

But never mind, the bag scanners, when a flap lifts up due to irregular shaped items, also hits you with a dose. You can feel good about this, because the security attendants will cop the most. Health fear over new airport scanners | Mail Online

This is completely wrong. The x-ray beam in a cabinet x-ray scanner does not point out the entry or exit to the machine. If this was the case the rubber flap being up or down would make no difference as the x-ray will pass straight through the rubber. They would also not be able to x-ray the bags going through the scanner. The beam must be aligned vertically.

edit: Good article about x-rays but pictures shows someone being scanned with a metal detector wand thingy.

The machines are referred to as 'low-dose', but there is a school of thought that there is no 'safe' radiation dose," said Dr Burnett, who has had 15 years' experience working in the NHS.

Actually the current international system of radiation protection is based on a theory that there is no safe level of radiation. However, there is plenty of research to say this is not a correct theory and just about no one believes the theory is correct. It is widely described as a useful tool for regulations.
Is this Dr Burnett associated with the so-called European Committee of Radiation Risk? If so, I wouldn't put much faith in his thoughts. That committee is very selective in ignoring research that doesn't agree with their ideas.

 

[ethernet]

Sounds less than neutral. At one stage, they were saying Agent Orange, Maralinga, and Iraqi DU exposure was also harmless - and may even be good for you. No thanks! I do believe the dose will fall into the trivial basket - if there is not a malfunction or maintenance stuff up.
People would be amazed at what nuclear bits are in a cigarette - but I digress.

I'd rather have no radiation. And I would not rather pay for it in hiked airport fees. I'm not convinced the money could not be better used in other ways. 'Security Theatre' is another term.

The thrust is gee whiz shock and awe technology, when the focus should be firmly on cost/risk benefit. Airport screening is an oxymoron.

Reading the links provided, reveals much. I am jumping to the conclusion that the British machines are similar the ones we have, although they could be Chinese, or Japanese. Wikipedia or Google can answer most of how it works. In one link "According to Rapiscan Systems, the California-based company which makes the machines, each scan generates only three microrems of radiation"

As for the bag scanners, why the hell to you see the dentist and the x-ray ologist step out the room behind lead glass? Answer, because in practice x-rays scatter, or what they hit may expel stuff that goes in other directions. They are more educated than the security chimps, and don't risk their bodies.

I don't want to say good or bad, or how it works, but say unnecessary risk is bad risk - end of story. Statistics may say the sum of these scans are long term killers, but we both know the dose at high altitudes are much worse.

The real idea in this lot, is having tags in place to measure the radiation.
Secondly, having a multitude of tags tuned/sensitive to different frequencies. I don't think this is being done.

If someone has a nuclear medicine background, I'll let them chime in, as I have trouble in accepting the contrary argument that radiation can good for you, as opposed to the sale of these machines is good for someones profits.

 

[medhead]

People would be amazed at what nuclear bits are in a cigarette - but I digress.

I'd rather have no radiation.

There is also a hell of a lot of tar in cigarette that is MUCH more damaging than a few radioactive atoms.

You seek no radiation sorry but it is all around you and it can not be escaped, it is in the dirt and sea water and even in your body. Radiation also comes from the sun.

As for the bag scanners, why the hell to you see the dentist and the x-ray ologist step out the room behind lead glass?

Real answer because they x-ray LOTS of people every day. Baggage x-rays have shielding to absorb any scatter, unlike dental or other medical x-ray machines. Baggage scanner also have a lot less scatter because they don't have to x-ray hard things that scatter an x-ray beam like the bones, or the x-ray table.

I don't want to say good or bad, or how it works, but say unnecessary risk is bad risk - end of story. Statistics may say the sum of these scans are long term killers, but we both know the dose at high altitudes are much worse.

Risk is part of living everything we do has risk. If you never left your house you still face many risks. I could avoid the unnecessary risks of driving to work everyday but then I would not have a job and I would face the risks of living rough and not having any food.

As for the statisitics, they say nothing at all about the risk of these scans. At the dose level of these scans you need to follow 61 million people for their whole life to get proper statistics about the risk of the scans. Cannot be done. End of story.

If someone has a nuclear medicine background, I'll let them chime in, as I have trouble in accepting the contrary argument that radiation can good for you,

Then explain a study of 2 groups of people with a certain type of cancer, one group got the normal treatment and 80% died after a certain amount of time. The other group got a low level whole body radiation dose (higher than what these scanners do) and 80% were still alive after the same amount of time.

 

[Will]

I think Medhead has dealt with pretty much all of your concerns. I can understand that you are worried, and that's perfectly understandable. I hope you take some comfort from the fact that a few people who have considerable knowledge about radiation have posted here trying to allay your concerns. This isn't a new thing, like agent orange, rather a thing that is already around you all the time, given in an infinitesimally higher dose.

Anyway, hopefully you'll be able to opt out, like in the US, and be manually searched.

 

[ethernet]

Agreed. Safe enough, with a cloud over cost effectiviness and meeting the 'whats in it for me' test.

Not all concerns have not been taken care of. Agreed that individual exposure - it is probably negligibish in the grand scheme of things. I also figure that the machine in dummy mode, flashing lights, when running with no operator, may serve a useful purpose, until it is actually switched on when COAG is in town.

1) The Cost, and un-published risk matrix of such devices adding value relative to other security measures, and the bias of what could be smuggled. Given what gets missed in luggage scans Vs on person, the smart money would be on directing it to an area of greater value.

2) I don't believe the claimed exposure figures, especially as they are orders of magnitude below the weakest of medical imaging. Ok, we agree bag scanners leak a little, especially dense things, like Hart's range geology rock cores in hand luggage. I'm not sure if the security chimps or their unions understand the probability of faulty equipment.

3) I know some pilots wear radiation exposure tags, and their exposure limit is lifted a tad, and compensation is not bad - but I have not noticed any in the screening areas on chimps or to detect malfunctions. They should. Trust nothing and measure after change. Remember the unmaintained Melbourne speed camera fiasco, were bald lies were the order of the day.

4) If there is reflection, a pax with their very own scanning receiver in the right place, might get that perfect Paris Hilton 'shot' from another angle, or play identify the air marshal with the solid objects game. Guess that is why millimetre wave tech got 2nd place in the trials.

5) Lets see the union demand some measurements, and toss a few rad tags around the place, to see if all those hard metal surfaces creates an unintended hot spot in the scanning area - aka system testing.

 

[possumoz]

Well I don't want strangers lookin' a me "bits". I just don't trust those ISS security at BNE. I wonder (if the machines are introduced) how long it'll be before we see a CM headlines screeching ' Qantas security in x ray cough xmas scandal', 'cause ya do know its only a matter of time before someone figures out a way to post pikkies on the net.