AW: [ RadSafe ] Re: Residential radon risk

[Bernard Cohen]

Philippe Duport wrote:

> Please see "Determination de la fraction libre d'activité existant 
> sous forme de RaA non attaché dans l'atmosphère d'une mine d'uranium" 
> by A. Chapuis, A. Lopez, J. Fontan, Health Physics Vol. 25, pp. 59-65 
> (1973).   At that time, Health Physics accepted papers in French!  The 
> fact that some papers were published in French or in languages other 
> than English does not imply that the research has not been done and 
> the information does not exist.
>
> Chapuis et al report unattached fraction values from 1 or 2% close to 
> an active stope, up to 15 to 20% without, or far enough from, active 
> mining operations.  Miners do not spend all their time in close 
> proximity to active mining operations.
>
> I measured  unattached fraction values of the order of 30% in an 
> isolated, inactive part of an underground uranium mine with forced 
> ventilation (P. Duport, G. Madelaine, A. Renoux. Mesure de la fraction 
> libre dans l'air d'une mine d'uranium laboratoire, Chemosphere 
> 4(5):283-288, 1975) - sorry, another paper in French.
>
> The unattached fraction is of course very sensitive to aerosol 
> concentration, but it is a serious mistake to assume that it is always 
> negligible in mines.
>
> Philippe Duport

       ----My apologies for aaying unattached fractions were close to 
zero in mines. The point is that they are presumably small enough and 
have little enough variability that they do not affect the radiation 
dose. If they did, it would not make sense to use WL as an index of 
radiation in mines