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Technical issues related to the ERICA Tool (on Facilia website)

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Posted: Asked by course participant (21-23 March 2012 Melbourne, Australia)
From:

Is high energy beta become low energy beta?

Question:
Is dividing beta emissions into two categories: low energy (< 10keV) and high energy (> 10 keV) an adequate simplification or does this introduce significant uncertainty for beta energy that is degrading as it enters the biota, losing energy in the process?

Answer:
Answered by Jordi Vives i Batlle (SCK•CEN, Belgium) 12/05/2012

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Posted: 05/03/2012
From:
Phil Crouch
Australia

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For instance the Am-241 EMCL is considerably below the WHO Guidance Level of 1 Bq/l (although the WHO GL for U-238 is 10 Bq/l).
There are also some ‘oddities’ between drinking water GLs and the concentration in water which would produce human food which would not be allowed into the foodchain, e.g. at 10 Bq/l of Cs (the WHO GL) the concentration in fish would be 25,000 Bq/kg.

DDrinking Drinking water standards are obviously set to limit the dose to humans from the consumption of water (for the WHO values aim seems to be to restrict dose to <0.1mSv/a via drinking water). In the case of wildlife then the organisms are permanently in water and potentially getting a dose from sediment (which may be the largest component of dose to the most exposed organism depending upon the radionuclide).

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D= DCC(ext, water) \[OF(water)\+ 0.5xOF(water surface)\+ 0.5xOF(sediment surface)\]xC(water) + \[OF(sediment)\+ 0.5xOF(sediment surface)\]xC(sediment). 

However, I have not been able to find any documentation that supports this.

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