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.
[1] https://radiopaedia.org/articles/dose-limits?lang=us
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5019040/
[3] https://www.sciencedirect.com/science/article/pii/S165836551...