Re: Radiation Units

[Ludwik Kowalski <kowalskiL@MAIL.MONTCLAIR.EDU>]

"Frohne, Vickie" wrote:

> 2 R per year is of the same order of magnitude as the 5 R/yr
> limit for radiation workers and, from what I recall, is
> approximately correct for airline personnel. ...

I still think that the airline personnel gets much less than
2 R/yr. The chart which Vickie found:

http://www.ans.org/pi/raddosechart/

shows that the cosmic rays contribution, at the elevations
8000 to 9000 feet is 96 mR (versus 26 mR at the ground
level). This factor of four should be corrected by the
reduction of the dose from the radioactivity of soil etc.
Using the factor of 4, ignoring the reduction, and assuming
somebody is flying for 10% of the total number of hours
in one year (probably an exaggeration ?), my estimate of
the added dose is 200 mR * 4 *0.1= 80 mR. This is 25
times less that 2 R. Where am I wrong in not accepting
that 2 R/yr is "approximately correct for airline personnel?"
Ludwik Kowalski