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Re: Domestic smoke detector disposal
Let me consider the ICRP/IAEA documents:
The ICRP 60 describes the condition of exemption at 7.8 (pages 64/66)
Article 287 - page 65, consider two reasons for exempting a source or an
environmental situation from regulatory control.
1. The source gives rise to small individual doses and small collective
doses in both normal and accident conditions.
2. No reasonable control procedures can achieve significant reductions in
individual and collective doses
After this article the others are very important to complement the basis for
exemption and how to apply it in general activities.
The IAEA BSS Safety Series 115 edition, 1996, was revised to reflect the
consensus surrounding these ICRP recommendations to exempt from regulatory
control and also to apply to waste and transport. The IAEA recommendation
refers to an individual dose of "some tens of microsieverts per year
(ÁSv/y)" as being trivial and therefore a basis for exemption from
regulatory control. Furthermore, the IAEA suggests that in order to account
for exposures from more than one exempt practice, the exposure to the
critical group from one such practice should be in the order of 10 ÁSv/y. In
addition the IAEA recommends a maximum collective dose commitment of 1 manSv
per year for each such practice. (GO TO ICRP 288 page 65 IAEA I-3, page 81).
It was recognized that the single exemption level of 70 Bq/g has no dose
basis and that it was unlikely that this level satisfied the primary dose
criterion of 10 microsievert in a year for exemption for all radionuclides.
Values were derived comparable to the exemption values and resulted in
recommended activity concentrations ranging from 1 to 10^6 Bq/g. and
Activities from 10^3 to 10^9 Bq.
Now lets go to the specific part of Smoke detector: - Two cases to consider:
a) Country has adopted the IAEA Basic Safety Standard
b) Country not has yet adopted and use 74 Bq/g
In the first case, Am-241 sources should be of order of 10 KBq (10 KBq
Exempt Activity for Am-241); sources with higher activity, and the common
smoke detector has around 35 KBq, a little higher than the IAEA value, in
this case cannot be only considered trivial doses, but optimization should
be taking into account, to IAEA recommendation of a maximum collective dose
commitment of 1 manSv
For political reasons and also technical circumstances, many countries have
accepted the exemption on the argument of minimum trivial doses, however
require to return old sources to supplier, and as general rule, to be
Warning: radioactive material
Trefoil radioactivity symbol
Identity and amount of radioactive material
Return to Competent Auhtority for Disposal, if country accept or
Return to supplier
Jose Julio Rozental
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