[ RadSafe ] Stack Emission Limits

[Wesley]

Barbara, and All,

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.

Second, I will comment on the 10 CFR 20.1101 constraint on airborne
effluents such that the individual member of the public likely to receive
the highest dose will not receive more than 10 millirem. I would like to
make two points.

1. This is a "constraint", not a limit. A licensee can exceed the 10 mrem/y
dose and not be in violation. It becomes a violation only if the licensee
does not report the exceedence to the NRC.

2. The 10 mrem/y constraint dose is meant to apply to real persons outside
the licensee's facility. So the licensee can take into account dilution in
the atmosphere up to the point of an actual public person. 

Thanks,
Wes

Best regards,
Wes
Wesley R. Van Pelt, PhD, CIH, CHP
Wesley R. Van Pelt Associates, Inc.
 

-----Original Message-----
From: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] On Behalf
Of BLHamrick at aol.com
Sent: Wednesday, February 07, 2007 11:54 PM
To: ograabe at ucdavis.edu; franz.schoenhofer at chello.at; RADCH-L at in2p3.fr;
radsafe at radlab.nl
Subject: Re: [ RadSafe ] Stack Emission Limits

 
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