AW: [ RadSafe ] Re: Residential radon risk

[GELSG at aol.com]

Phillipe:
 
Thank you for the reference.  I realize that under certain conditions  of 
ventilation and filtration, the unattached fraction can range widely.   However, 
my point was that using laboratory or mining data to discourage home  use of 
electrostatic air cleaners may be a mistake.
 
Gerald Gels
 
In a message dated 6/1/2005 9:31:31 A.M. Eastern Standard Time,  
pduport at uottawa.ca writes:

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