The Health Physics Society (HPS) reports that a person undergoing a backscatter scan receives approximately 0.05 μSv (or 0.005 mrems) of radiation; American Science and Engineering Inc. reports 0.09 μSv (0.009 mrems). At the high altitudes typical of commercial flights, naturally occurring cosmic radiation is considerably higher than at ground level. The radiation dose for a six hour flight is 20 μSv (2 mrems) - 200 to 400 times larger than a backscatter scan. According to U.S. regulatory agencies, "1 mrem per year is a negligible dose of radiation, and 25 mrem per year from a single source is the upper limit of safe radiation exposure".
The radiation exposure with Backscatter X-Ray's is really a non-issue.
IMO its much more damning to bring on the "think of the children"/"The Chinese government can hack your wife's nude pics" angle to convince the public against these machines.
"However, researchers at the University of California, San Francisco, have argued that the amount of radiation is higher than claimed by the TSA and body scanner manufacturers because the doses were calculated as if distributed throughout the whole body, but the radiation from backscatter x-ray scanners is focused on just the skin and surrounding tissues"
"Furthermore, other scientists claim the health effects are backscatter are well understood whereas those from millimeter wave scanners are not"
Some of the machines being deployed by the TSA are millimeter wave scanners, BTW.
> The radiation exposure with Backscatter X-Ray's is really a non-issue.
Unfortunately that's not the case.
"David Brenner, the head of Columbia University’s Centre for Radiological Research, says the concentration on the skin – one of the most radiation-sensitive organs of the body – means the radiation dose is actually 20 times higher than the official estimate."
The two issues are that 1) the energy is absorbed by the surface of the body instead of throughout the volume, so the effective dose to affected tissues is much higher, and 2) that the dose is received in seconds, instead of over a period of hours.
For a frequent traveler flying about once a week, ~100 departures per year, if scanned every time that adds a non-trivial 10-20 mrem.
And that's assuming that the cited dose is correct and not a significant under-estimate; where's the independent testing?
Here's a long post with numerous references regarding this general topic:
The Health Physics Society (HPS) reports that a person undergoing a backscatter scan receives approximately 0.05 μSv (or 0.005 mrems) of radiation; American Science and Engineering Inc. reports 0.09 μSv (0.009 mrems). At the high altitudes typical of commercial flights, naturally occurring cosmic radiation is considerably higher than at ground level. The radiation dose for a six hour flight is 20 μSv (2 mrems) - 200 to 400 times larger than a backscatter scan. According to U.S. regulatory agencies, "1 mrem per year is a negligible dose of radiation, and 25 mrem per year from a single source is the upper limit of safe radiation exposure".
The radiation exposure with Backscatter X-Ray's is really a non-issue.
IMO its much more damning to bring on the "think of the children"/"The Chinese government can hack your wife's nude pics" angle to convince the public against these machines.