Re: Personal CAM for alpha

[LIPTONW@dteenergy.com]

Please consider: 
 
1.  How's someone going to carry the detector and electronics, eg., a 
photomultiplier tube!, on his lapel? 
 
2.  Even if you could, how would you separate the TRU from the Rn daughters?
 
For example, assume that the airborne concentration of Pu-239 is 100 DAC = 3 
E-10 uCi/ml.  Assume that the cam is operating at the reference man
breathing 
rate of 20 liters/min.  Then, the cam would sample 9.6 E6 ml in an 8 hour 
shift, and, assuming 100% filter collection efficiency, the total activity 
sampled would be less than 3 nCi.  I doubt that this can be detected by 
available instrumentation without letting the background decay.  Dust
buildup 
on the filter would degrade both the detector efficiency and the alpha 
spectrum, so I doubt that, even with spectroscopy, the TRU alphas could be 
separated out in real time.    
 
3.  Why do you feel the need to provide alpha cam's?  Your radiological 
controls should be good enough to prevent sudden changes in airborne levels 
during routine operations.  For those nonroutine operations, such as system 
breaches, where there is a likelihood of a release, the workers should be 
wearing adequate respiratory protection. 
 
The opinions expressed are strictly mine. 
It's not about dose, it's about trust. 
 
Bill Lipton 
liptonw@dteenergy.com 
 
You wrote: 
 
>Does anyone know of a lapel type/size alpha continuous air monitor.  This 
>device would provide a continuous indication of alpha airborne
radioactivity 
>to the wearer. 
 
>Please respond to: 
 
>Tom Goff 
>Rad Engineering 
>Rocky Flats ETS 
>Tom.Goff@RFETS.gov 

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