Re: progeny nuclides and ALI/DAC

[Jean-Michel Mure <jm.mure@andra.fr>]

Andrew,

You can find an answer in ICRP 30 Part 1 - Vol2, 3/4, 1979 § 4.6.1. p 18
Build-up of radioactive daughters.

Progeny nuclides are taken into account only once the Bq has entered the
body and decays in it. However, if a radionuclide is in equilibrium before
it is incorporated (ingestion or inhalation), it is not treated by the ALI
or DAC and it has to be taken into account by adding progeny ALI or DAC to
the that.
In some cases, it can increase the dose factor of many orders of magnitude
(Cs137, Sr90, Ra226, U238 ...)

JM Mure


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Jean-Michel MURE
French National Radwaste Management Agency (ANDRA)
Safety Division/Security and Radiological Protection Department
Parc de la Croix Blanche
1-7, rue Jean Monnet
92290 CHATENAY MALABRY Cedex
FRANCE
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Tel : 01 46 11 83 74
Fax : 01 46 11 80 13
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Email : jm.mure@andra.fr
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