In article ,
Brian Gaff wrote:
After reading some recent reports mentioning ex astronauts now on ground
duties, I wondered if there was some kind of exposure limit for those who
have done long duration flights, at least in the US.

Yes, there is. As I understand it, NASA's radiation rules generally
follow the recommendations of NCRP-98, "Guidance on Radiation Received
in Space Activities", 1989, from the National Council on Radiation
Protection and Measurements, although those are now thought to be a
bit too generous for long-term exposures.

Astronauts are legally radiation workers, so monitoring of doses, work
rules that limit them, and efforts to keep them as low as possible, are
legally mandatory.
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"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |