[ RadSafe ] Stack Emission Limits

[BLHamrick at aol.com]

Otto,
 
You have read the regulations correctly.  The effluent "limits" in 10  CFR 20 
do not have associated peak concentrations, they are annual  averages.  I say 
"limits" in quotation marks, because they are not actual  limits, but rather 
may be used to demonstrate compliance with the annual public  dose limit in 
20.1301 (100 mrem/year).
 
I would expect that if, in fact, a member of the public received a dose in  
excess of 100 millirem during an "ultra-high concentration" release that it  
would negate any argument made by the licensee that they were meeting the annual 
 average release concentrations despite these unusual conditions in order to  
demonstrate compliance with 20.1301.
 
Also, as Mr. Bragg just noted, 10 CFR 20.1101 imposes an additional  
constraint on the effluents such that the individual member of the public likely  to 
receive the highest dose will not receive more than 10 millirem.   Although 
called a constraint, functionally this appears to serve as more of a  "limit" 
than the release concentrations provided in 10 CFR 20, Appendix B.
 
Barbara L. Hamrick
 
In a message dated 2/7/2007 10:58:45 A.M. Pacific Standard Time,  
ograabe at ucdavis.edu writes:

February  7, 2007

10 CFR Part 20 sets annual average limitation for stack  emissions in the 
United States.  For example, for carbon-11 monoxide,  the annual average 
concentration is given as 2E-6 microcuries per  milliliter of air. [Sorry 
about the American units.] .

My question  concerns a brief ultra-high concentration emission that may 
occur only  occasionally and last only a few seconds. Is there a peak limit 
for such  an emission? I can always run my exhaust fans for a year to get 
the  average down to the allowed annual average, but even if the exhaust 
fans  were turned off after an emission event there is no real difference in  
potential exposure risk.  But it seems that I can meet the release  limit by 
simply running my fans while there are no  emissions.

Comments please.