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RE: Area Postings for Beta
NRC Question and Answer (Q&A) #74 states that for purposes of posting an
area, the "dose equivalent" used in the definitions of RA, HRA and VHRA are
all considered to be at a tissue depth of 1 cm (1000 mg/cm^2), i.e., DDE.
Q&A information can be obtained from the NRC Web site:
http://www.nrc.gov/NRC/NMSS/HP/QA/index.html
-----Original Message-----
From: x [mailto:netngatr@magnolia.net]
Sent: Friday, September 10, 1999 12:51 AM
To: Multiple recipients of list
Subject: Area Postings for Beta
This is a multi-part message in MIME format.
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Fellow RADSAFERS,
=20
I've searched the RADSAFE archives and can't find exactly what I'm =
looking for. I know someone out there has the solution, I haven't seen =
a question yet go unanswered.
I would appreciate any opinions, practices, and references you may have =
dealing with the posting of areas due to beta radiation where DDE from =
beta is not a concern.
Assume the only source of radiation is power plant components with mixed =
fission/corrosion products and no significant gamma contribution to dose =
rates. The beta energies are low enough that DDE from beta is not =
significant, documented in past studies.
1. Do you post 'Radiation Area' signs for those areas that exceed 5 =
mrem/hr beta @30 cm from the source, or HRA signs for 100 mrem/hr beta =
@30cm? Since the 10CFR20.1003 definition of RA and dose equivalent do =
not differentiate between DDE and SDE, it seems clear to me that posting =
is required.
2. Assume these high levels of contamination are now wrapped with =
plastic to preclude requiring protective clothing for handling the item, =
but >100 mrem/hr beta @30 cm penetrates the plastic. Does anyone use a =
"Beta High Radiation Area" posting or similar to ensure SDE or extremity =
monitoring when handling such wrapped items?
3. Do all of the normal requirements for a HRA entry apply? (Tech Specs =
similar to RegGuide 8.38)
Thanks for your help,
Richard Sumrall
HP Instructor
Grand Gulf Nuclear Station
rsumral@entergy.com
My personal questions and musings only, not reviewed or endorsed by my =
employer.
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<META content=3Dtext/html;charset=3Diso-8859-1 =
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<DIV><FONT color=3D#000000 size=3D2>Fellow RADSAFERS,</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2></FONT> </DIV>
<DIV><FONT size=3D2>I've searched the RADSAFE archives and can't find =
exactly what=20
I'm looking for. I know someone out there has the solution, =
I=20
haven't seen a question yet go unanswered.</FONT></DIV>
<DIV><FONT size=3D2></FONT> </DIV>
<DIV><FONT size=3D2>I would appreciate any opinions, practices, and =
references you=20
may have dealing with the posting of areas due to beta radiation where =
DDE from=20
beta is not a concern.</FONT></DIV>
<DIV>
<DIV><FONT color=3D#000000 size=3D2></FONT> </DIV></DIV>
<DIV><FONT color=3D#000000 size=3D2>
<DIV><FONT color=3D#000000 size=3D2>Assume the only source of radiation =
is power=20
plant components with mixed fission/corrosion products and no =
significant gamma=20
contribution to dose rates. The beta energies are low enough that =
DDE from=20
beta is not significant, documented in past studies.</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2></FONT> </DIV>
<DIV><FONT color=3D#000000 size=3D2>1. Do you post 'Radiation =
Area' signs for=20
those areas that exceed 5 mrem/hr beta @30 cm from the source, or HRA =
signs for=20
100 mrem/hr beta @30cm? Since the 10CFR20.1003 definition of RA =
and dose=20
equivalent do not differentiate between DDE and SDE, it</FONT><FONT=20
color=3D#000000 size=3D2> seems clear to me that posting is =
required.</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2></FONT> </DIV>
<DIV>2. Assume these high levels of contamination are now wrapped =
with=20
plastic to preclude requiring protective clothing for handling the item, =
but=20
>100 mrem/hr beta @30 cm penetrates the plastic. Does anyone =
use a=20
"Beta High Radiation Area" posting or similar to ensure SDE or =
extremity monitoring when handling such wrapped items?</DIV>
<DIV></FONT> </DIV>
<DIV><FONT size=3D2>3. Do all of the normal requirements for a HRA entry =
apply?=20
(Tech Specs similar to RegGuide 8.38)</FONT></DIV></DIV>
<DIV> </DIV>
<DIV><FONT color=3D#000000 size=3D2>Thanks for your help,</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>Richard Sumrall</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>HP Instructor</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>Grand Gulf Nuclear =
Station</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2><A=20
href=3D"mailto:rsumral@entergy.com";>rsumral@entergy.com</A></FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2></FONT> </DIV>
<DIV><FONT size=3D2>My personal questions and musings only, not reviewed =
or=20
endorsed by my employer.</FONT></DIV></BODY></HTML>
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