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Assuming it's a real study and they actually gather new data and run some experiments, what are the possible results? 1) The machines are unsafe and should be

Assuming it's a real study and they actually gather new data and run some experiments, what are the possible results? 1) The machines are unsafe and should be removed immediately 2) The machines are unsafe for people that pass through them at some given frequency (like 5x a year or something) 3) The machines are completely safe 4) ? Results 1 and 2 would mean that many air travelers would feel entitled to some sort of compensation. There's going to be a lot of external pressure to find result #3, so I'm glad it's an 'independent' study.

stcredzero 14y ago
In all likelihood, the conclusion will be #3. If government agencies feel compelled to do such studies beforehand from now on, then change has occurred in the right direction.
- nullc 14y ago
  If it's (3) saying in _zero_ harm then it's almost certantly a lie (http://en.wikipedia.org/wiki/Linear_no-threshold_model http://en.wikipedia.org/wiki/Linear_no-threshold_model), if it's a (3) saying the harm is very low and so it wins on cost benefit — well, that is possible but it seems really unlikely considering how insanely low the base rate of terrorism is, much less the subset of attacks which the scanners actually prevent (vs just shuffling around the attack mechanisms).
  - pdonis 14y ago
    it seems really unlikely considering how insanely low the base rate of terrorism is, much less the subset of attacks which the scanners actually prevent This is an argument for not screening passengers, or at least doing it very differently from the way we do now. It's not an argument for using one type of scanner rather than another, given that you are going to screen with scanners. That's the only question at issue in the OP: whether TSA should use X-ray scanners or another type.
    - stcredzero 14y ago
      The cost/benefit is likely to be different between the X-ray backs after and millimeter wave scanners.
      - pdonis 14y ago
        Different, sure. But different doesn't necessarily mean better.
        jlgreco 14y ago
        Explain how risk/reward could be different without one being better than the other. Is one going to come out as an imaginary number or something? Actually, now that I think about it more, you're probably going to be dividing by zero to calculate that risk over reward so testing equality will be a challenge...
        pdonis 14y ago
        Because risk/reward requires tradeoffs; it isn't a single linear scale. Different tradeoffs can be judged differently based on who is doing the judging and what criteria they are using. There isn't a single "right answer".
        jlgreco 14y ago
        For anyone's subjective answer, one is going to be better than the other, unless they are freakishly identical. Whoever provides the most rational defense of their analysis is the person we listen to. We don't need to play fast and loose with the calculation though. Real data would be trivial to accumulate, were it permitted.
    - gknoy 14y ago
      If more people are likely to die per year from cancer caused by the scanners than are likely to die from terrorists, I think that's a convincing argument that using the scanners screen passengers is worse than not screening them at all.
  - glenra 14y ago
    It's actually plausible that the scanners - if working as designed - might cause net health benefit ( http://en.wikipedia.org/wiki/Radiation_hormesis http://en.wikipedia.org/wiki/Radiation_hormesis http://en.wikipedia.org/wiki/Hormesis http://en.wikipedia.org/wiki/Hormesis ). The tricky thing is that we have no way of knowing if the machines are operating as designed and the powers that be have a looooong history of outright lying to passengers. I still remember when they told people sending your camera through the X-ray wasn't bad for the film - this was a lie, but it made security's job easier to tell that lie, so they told it. Knowing that the TSA is a bunch of incompetent and untrustworthy nitwits, I don't trust them to operate dangerous equipment safely. Since a machine that's not being maintained correctly or isn't being used correctly could be really dangerous, I generally choose to opt out.
dmm 14y ago
There are tons of different possible results, depending on what they measure. Maybe the machines are dangerous for the people who work around them every day. Why aren't these people wearing dosimeters? Maybe the machines have an effect that only appears in a very small percentage of individuals. Maybe the danger only comes after the machine drifts out of calibration, while in a humid room, operated by poorly trained persons who misinterpret a control panel, when the person scanned has a given gene, that is being expressed because they have a viral infection. Conclusion 3(that you listed) can only be considered crap. To arrived at it is to claim to have a perfect understanding of several very complex systems. No matter how many studies you perform that fail to find a danger, that is not evidence that no danger exists. "The absence of evidence is not evidence of absence." The most you can ever say is "We found no evidence of dangers."
digikata 14y ago
My issue is with what threshold of safety should be considered. If for example, the X-ray dose causes one fatal cancer in a million, it would be a positive risk-benefit for many medical procedures, but for the rate of actual terrorism attempts vs air travelers getting that dose millions of times over, the risk benefit seems pretty negative. This is especially true if you're a frequent air traveller and could be dosed two or more times per trip. That really means that airport X-ray machines should be held to a much higher safety standard then medical x-rays.
- pdonis 14y ago
  My issue is with what threshold of safety should be considered. That's a good question. The numbers TSA gives, which are quoted in the article, are that a single exposure to the X-ray scanner gives you the same radiation dose that you get from two minutes of airline flight. So if we think the risk of the scanner is unacceptable, we should also consider it unacceptable for a flight to be lengthened by two minutes. Flight times routinely vary by more than that due to re-routings for things like weather, air traffic control, etc. Nothing is 100% safe. If we are going to try to consider thresholds of safety, we have to consider all possible risks, not just the ones the media is currently harping on. What we find when we do that is that we routinely accept risks far greater than the ones the media is currently harping on. But those risks don't sell papers or keep people watching.
  - digikata 14y ago
    The minutes of flight are there because they're a fundamental part of travel and are unavoidable if you choose to travel by air. An x-ray machine is there only for the purpose of additional security. If the risk undergone for the machine outweighs the security benefit then the machine can and should be removed. In my mind, there is no equivalence between the unavoidable risk and the completely avoidable risk.
    - krschultz 14y ago
      A lot of flight time is unnecessary. The technology to more efficiently route airplanes exists, we just have not yet allocated the money to do it. If it turns out that the X-rays really are no worse than 2 extra minutes of flights, I'd rather put the money towards improving the air traffic control infrastructure. Then we save time, reduce radiation exposure, and likely reduce the risk of an airplane crash. Seems like a better use of money to me.
jdechko 14y ago
Those are the results of the study, but what I'm more curious about is what will come out of the findings. That is, if the machines are found to be unsafe to some level, will the TSA actually remove them from use?
aliguori 14y ago
4) Study finds the scanners are unsafe, contradicting what the companies selling the scanners claim. TSA sues companies providing the scanners and makes them the scape-goat Perhaps it's wishful thinking, but one can hope...

stcredzero 14y ago

In all likelihood, the conclusion will be #3. If government agencies feel compelled to do such studies beforehand from now on, then change has occurred in the right direction.

nullc 14y ago
If it's (3) saying in _zero_ harm then it's almost certantly a lie (http://en.wikipedia.org/wiki/Linear_no-threshold_model http://en.wikipedia.org/wiki/Linear_no-threshold_model), if it's a (3) saying the harm is very low and so it wins on cost benefit — well, that is possible but it seems really unlikely considering how insanely low the base rate of terrorism is, much less the subset of attacks which the scanners actually prevent (vs just shuffling around the attack mechanisms).
- pdonis 14y ago
  it seems really unlikely considering how insanely low the base rate of terrorism is, much less the subset of attacks which the scanners actually prevent This is an argument for not screening passengers, or at least doing it very differently from the way we do now. It's not an argument for using one type of scanner rather than another, given that you are going to screen with scanners. That's the only question at issue in the OP: whether TSA should use X-ray scanners or another type.
  - stcredzero 14y ago
    The cost/benefit is likely to be different between the X-ray backs after and millimeter wave scanners.
    - pdonis 14y ago
      Different, sure. But different doesn't necessarily mean better.
      - jlgreco 14y ago
        Explain how risk/reward could be different without one being better than the other. Is one going to come out as an imaginary number or something? Actually, now that I think about it more, you're probably going to be dividing by zero to calculate that risk over reward so testing equality will be a challenge...
        pdonis 14y ago
        Because risk/reward requires tradeoffs; it isn't a single linear scale. Different tradeoffs can be judged differently based on who is doing the judging and what criteria they are using. There isn't a single "right answer".
        jlgreco 14y ago
        For anyone's subjective answer, one is going to be better than the other, unless they are freakishly identical. Whoever provides the most rational defense of their analysis is the person we listen to. We don't need to play fast and loose with the calculation though. Real data would be trivial to accumulate, were it permitted.
  - gknoy 14y ago
    If more people are likely to die per year from cancer caused by the scanners than are likely to die from terrorists, I think that's a convincing argument that using the scanners screen passengers is worse than not screening them at all.
- glenra 14y ago
  It's actually plausible that the scanners - if working as designed - might cause net health benefit ( http://en.wikipedia.org/wiki/Radiation_hormesis http://en.wikipedia.org/wiki/Radiation_hormesis http://en.wikipedia.org/wiki/Hormesis http://en.wikipedia.org/wiki/Hormesis ). The tricky thing is that we have no way of knowing if the machines are operating as designed and the powers that be have a looooong history of outright lying to passengers. I still remember when they told people sending your camera through the X-ray wasn't bad for the film - this was a lie, but it made security's job easier to tell that lie, so they told it. Knowing that the TSA is a bunch of incompetent and untrustworthy nitwits, I don't trust them to operate dangerous equipment safely. Since a machine that's not being maintained correctly or isn't being used correctly could be really dangerous, I generally choose to opt out.

dmm 14y ago

There are tons of different possible results, depending on what they measure. Maybe the machines are dangerous for the people who work around them every day. Why aren't these people wearing dosimeters? Maybe the machines have an effect that only appears in a very small percentage of individuals. Maybe the danger only comes after the machine drifts out of calibration, while in a humid room, operated by poorly trained persons who misinterpret a control panel, when the person scanned has a given gene, that is being expressed because they have a viral infection. Conclusion 3(that you listed) can only be considered crap. To arrived at it is to claim to have a perfect understanding of several very complex systems. No matter how many studies you perform that fail to find a danger, that is not evidence that no danger exists. "The absence of evidence is not evidence of absence." The most you can ever say is "We found no evidence of dangers."

digikata 14y ago

My issue is with what threshold of safety should be considered. If for example, the X-ray dose causes one fatal cancer in a million, it would be a positive risk-benefit for many medical procedures, but for the rate of actual terrorism attempts vs air travelers getting that dose millions of times over, the risk benefit seems pretty negative. This is especially true if you're a frequent air traveller and could be dosed two or more times per trip. That really means that airport X-ray machines should be held to a much higher safety standard then medical x-rays.

pdonis 14y ago
My issue is with what threshold of safety should be considered. That's a good question. The numbers TSA gives, which are quoted in the article, are that a single exposure to the X-ray scanner gives you the same radiation dose that you get from two minutes of airline flight. So if we think the risk of the scanner is unacceptable, we should also consider it unacceptable for a flight to be lengthened by two minutes. Flight times routinely vary by more than that due to re-routings for things like weather, air traffic control, etc. Nothing is 100% safe. If we are going to try to consider thresholds of safety, we have to consider all possible risks, not just the ones the media is currently harping on. What we find when we do that is that we routinely accept risks far greater than the ones the media is currently harping on. But those risks don't sell papers or keep people watching.
- digikata 14y ago
  The minutes of flight are there because they're a fundamental part of travel and are unavoidable if you choose to travel by air. An x-ray machine is there only for the purpose of additional security. If the risk undergone for the machine outweighs the security benefit then the machine can and should be removed. In my mind, there is no equivalence between the unavoidable risk and the completely avoidable risk.
  - krschultz 14y ago
    A lot of flight time is unnecessary. The technology to more efficiently route airplanes exists, we just have not yet allocated the money to do it. If it turns out that the X-rays really are no worse than 2 extra minutes of flights, I'd rather put the money towards improving the air traffic control infrastructure. Then we save time, reduce radiation exposure, and likely reduce the risk of an airplane crash. Seems like a better use of money to me.

jdechko 14y ago

Those are the results of the study, but what I'm more curious about is what will come out of the findings. That is, if the machines are found to be unsafe to some level, will the TSA actually remove them from use?

aliguori 14y ago

4) Study finds the scanners are unsafe, contradicting what the companies selling the scanners claim. TSA sues companies providing the scanners and makes them the scape-goat Perhaps it's wishful thinking, but one can hope...