[ RadSafe ] Stack Emission Limits

[BLHamrick at aol.com]

Wes,
 
I'm not sure why you think what you state below.
 
Let's just examine Cs-137.  With an inhalation ALI of 100 uCi (-->  5rem), we 
can assume that 2 uCi inhaled would equate to 100 millirem (the public  dose 
limit).  So, if, for example, I exhausted a concentration of 1E-4  uCi/ml for 
1 min at the boundary of my restricted area, and some member of the  public 
was doing some "light work" at that very location, he/she would  inhale:
 
1E-4 uCi/ml x 2 E+4 ml/min  (standard "light work" breathing  rate) x 1 min = 
2 uCi (--> 100 mrem);
 
However, if that was my only release in that year, my annual average  release 
concentration would be:
 
[(1E-4 uCi/ml x 1 min) + (0 uCi/ml x 525,599 min)]/525,600 min (per  year) = 
1 E-10 uCi/ml, which is less than the 10 CFR 20, Appendix B  effluent limit 
for Cs-137 (which is 2 E-10 uCi/ml).
 
Thus, I would meet the Appendix B limit, but still have exposed an  
individual member of the public to 100 millirem in a year.
 
Am I missing something?
 
Barbara
 
In a message dated 2/8/2007 8:18:25 A.M. Pacific Standard Time,  
wesvanpelt at verizon.net writes:

First,  if a licensee meets the annual average air concentration limits, the
dose  to a member of the public WILL be less than 100 mrem. In fact, it will
be  less than 50 mrem. This is true even if the air emission is done in a
very  short time, say only 5 or 10 minutes during the entire  year.