Re: Livermore Pu

[Franz Schoenhofer <schoenho@via.at>]

At 11:17 22.02.1999 -0600, you wrote:
>Dear Ruth,
>
>I have a problem with your numbers! I would not call (10 +-5)  X or
>(10 +- 10) X really different from zero, confidence level 90% or 95%
>or not.  I just would not trust those numbers.  Let us remember that
>this is a difference [(effect + bgrd) - bgrd].  Do you know what game
>of "Now you see it, and now you don't" is being played here?  Pu is
>the most dangerous substance.....so we have to be extra careful?
>
>Regards
>
>Fritz


Fritz,

I disagree. First of all PU (which isotope??????) is not the most dangerous
substance at all, Ra-226 is more toxic by orders of magnitude, not to talk
about other radionuclides from the natural decay chains. Using 2 sigma is
in my opinion not sufficient at all. We use in my lab 3 sigma. I know that
many US laboratories use 4.65 sigma. Of course I am aware that some people
use 1.65 sigma or 2 sigma for their results, because otherwise they would
be lower than the lower limit of detection and nobody would care for them.....

And, what is the "background"? Pu-239 is abundant everywhere, in the
tropics, in the arctic, in the antarctic, in the moderate zones..... This
is thanks to the atmospheric nuclear tests of the so called super powers
USA, USSR, much less to GB, France, China........ Fortunately most
Pu-compounds in the environment are insoluble.

I think that health physicists should stick to facts and scientific
knowledge and not what some groups with clear intentions spread.

Franz


Franz Schoenhofer
Habicherg. 31/7
A-1160 Vienna
Austria
Tel.: +43-1-495 53 08
Fax.: same number
mobile phone: +43-664-338 0 333
e-mail: schoenho@via.at

Office:
Hofrat Dr. Franz Schönhofer
Federal Institute for Food Control and Research
Department of Radiochemistry
Kinderspitalg. 15
A-1095 Vienna
Austria
Tel.: +43-1-40 490 27820
e-mail: schoenhofer@baluf.via.at
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