That second link says "each full body scan of an individual would generate 6 Micro Sieverts (µSv)" so 2 scans per day would be 12 µSv, and a dose chart [0] shows the average daily background dose to be 10 µSv while a flight from NY to LA is 40 µSv. So it's a bit like taking that flight every 3.3 days. So maybe it's no worse than being a pilot / flight attendant?
2 scans a day for 1 year would be 4,380 µSv, or 4.3 mSv. The yearly dose limits recommended by the International Commission on Radiological Protection (ICRP) is 1 mSv per year for the general public, and 20 mSv for “occupationally exposed workers” [1]. Since Assange is receiving this for very specific reasons, I don’t think he would fall into the general public. So he is receiving less than a quarter of what is considered max safe for a radiation worker. For further comparison, long haul airline pilots receive and average of 2.94 mSv/year [2] and “diagnostic radiology, nuclear medicine, and radiotherapy workers were found to be 0.66, 1.56, and 0.28 mSv, respectively” [3]. So he could be on the high end when compared to medical workers and pilots, while still being well under the safe max limits.
Thanks, this is very informative. Does the peakiness of being subject to X-ray scanning (a duty cycle like 500ms on, 12hr off) come into play when comparing with those other occupations, though?
First, I am probably as much as a layman as you. But from what I have read and some quick googling now, there is no additional risk or appreciative difference. Although I did find a few regulations that the general public should not be exposed to any sort of radiation higher than 10 µSv per hour. However I believe that is to prevent regular people unknowingly being around high radiation sources that would add up to a high cumulative total, since the general public does not have any way to track their cumulative exposure, not a problem with that level of single dose radiation per se.
Ionizing radiation damage is overwhelmingly and almost exclusively in its cumulative effects, namely the cancer it can cause. Each “unit” of radiation has a certain likelihood of slicing through the DNA of one of your cells, which has a certain likelihood of causing a mutation, which has a certain likelihood of being a cancerous mutation and not a “kills the cell” mutation, which has a certain likelihood of being a specific type that can evade all the body’s natural defenses against rouge cells. It is a long chain of dice rolls that have to all go just wrong.
So, unless the dose is concentrated to a physical location, e.g. radon in the lungs or sunburn on the skin, then it doesn’t really matter if you get a given dose over a month or a year. It will still start the same number of cascading dice rolls.
If someone that actually knows what they are talking about feels the need to correct anything, please do.
12 µSv in two 500 ms bursts is very different 12 µSv spread out over 1 hour of flight time.
The difference in intensity is 3,600 fold. It's the difference between being subjected to 1 hour of 30 degree celcius heat and 1 second of 108,000 degree celcius heat.
To bolster your argument: only the Kelvin scale is eligible for multiplication operations, so 30C * 3600 = 1,091,067C when converting to K and back.
On the other hand: I expect 500 ms of such extreme heat would instantly kill a human, although I'm having a hard time finding an answer for such a short time scale. Since X-ray imaging doesn't instantly kill, it's apples and oranges, but point taken.
[0] https://www.pbs.org/wnet/need-to-know/the-daily-need/how-muc...