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Is Tritium Really That "Nasty"?
Schoenhofer wrote:
> I dislike furthermore the idea of living in a tritium world, where the
> "clean" fusion energy has replaced the "dirty" nuclear energy - don't you?
Actually I don't mind living in a world contaminated with radioactive
material, tritium or any other radionuclide. We already do. The real
question here, to me, has more to do with how much radioactive material
is permitted to be on materials and items released from nuclear
facilities to uncontrolled use. From the risk standpoint (e.g. dose to
the public), depending on the dose limit selected, one can easily detect
the radioactive material on such items if the permitted dose is 10 mrem
per year. If the permitted dose is reduced significantly, then
detection becomes impractical. We are working on an American National
Standard that defines the contamination on surfaces and in volumes of
items released for uncontrolled use. That standard is risk-based, not
detection based, although detection is considered in setting forth the
permitted contamination limits.
My main concern is that the dose limit selected for that standard is too
low: 10 mrem per year. In addition, the models used to calculate
permissible contamination at that dose rate are very conservative.
Finally, it is highly unlikely that many, if any, members of the
public would ever be exposed to such a dose from such items, even if the
models were not conservative. So - here we go again - telling, by
implication, the public (who may read the standard) that more than 10
mrem per year is not safe. And then use conservative calcualtions to
translate that dose into permissible contamination levels that are
conservative with respect to the dose limit.
What's wrong with having a contamination limit of 100,000 dpm per 100
square centimeters on items contaminated with tritium and are to be
released for uncontrolled use? In the USA we are held to 10,000 dpm per
100 square centimeters, even though conservative calculations say the
higher number will not produce a dose to a member of the public of
greater than 10 mrem per year. Al Tschaeche xat@inel.gov