[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Area Postings for Beta.
Oops.
Thanks for the help. I didn't remember this topic being in there, so I
didn't check. Guess it's time to read all of them again.
Thanks again,
Richard
-----Original Message-----
From: Brent_Robinson@fpl.com <Brent_Robinson@fpl.com>
To: Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
Date: Friday, September 10, 1999 4:06 AM
Subject: Re: Area Postings for Beta
>The NRC Questions and Answers provides the "answer" to your question ....
>available on the NRC internet site.
>The most applicable questions and answers are:
>
>Question 221: Since the posting requirements are all in
>terms of deep dose equivalent, what requirements should be
>followed when posting for low energy beta radiation?
>
>Answer: Unless the beta particle can deliver a dose at a
>issue depth of 1 cm, the area does not require posting as
>a radiation area (20.1902 (a)), high radiation area
>(20.1902 (b)), or very high radiation area (20.1902 (c));
>however, posting for airborne radioactivity area (20.1901
>(d)) and for areas or rooms in which licensed material is
>used or stored (20.1901 (e)) needs to be considered for
>beta emitters. See Questions and Answers 57, 74, and 85
>for more information. (Reference: 10 CFR 20.1902, 10 CFR
>20.1901)
>
>
>Question 74: Dose rates are used to establish posting
>requirements for radiation areas, high radiation areas, and
>very high radiation areas. 10 CFR 20.1601 (a) (1),
>"Control of Access to High Radiation Areas," refers to a
>"deep-dose equivalent" in describing when a control device
>should be provided to reduce radiation doses below 0.1 rem
>in one hour, thus implying that the "dose equivalent" in
>the definition of a "high radiation area" is the "deep dose
>equivalent" [at a tissue depth of 1 cm (1000 mg/square
>cm)]. Are the "dose equivalent" in the definitions of
>"radiation area" and "high radiation area" and the "dose"
>in the definition of "very high radiation area" all
>considered to be at a tissue depth of 1 cm (1000 mg/square
>cm)?
>
>Answer: Yes. In addition see Question 57. (References:
>10 CFR 20.1003, 10 CFR 20.1601)
>
>
>
>
>
>"x" <netngatr@magnolia.net> on 09/10/99 12:51:30 AM
>
>Please respond to radsafe@romulus.ehs.uiuc.edu
>
>To: Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
>cc: (bcc: Brent Robinson/Psl/Nuclear/FplNuc)
>Subject: Area Postings for Beta
>
>
>
>
>This is a multi-part message in MIME format.
>
>------=_NextPart_000_0022_01BEFB1D.4C14AF80
>Content-Type: text/plain;
> charset="iso-8859-1"
>Content-Transfer-Encoding: quoted-printable
>
>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.
>
>------=_NextPart_000_0022_01BEFB1D.4C14AF80
>Content-Type: text/html;
> charset="iso-8859-1"
>Content-Transfer-Encoding: quoted-printable
>
><!DOCTYPE HTML PUBLIC "-//W3C//DTD W3 HTML//EN">
><HTML>
><HEAD>
>
><META content=3Dtext/html;charset=3Diso-8859-1 =
>http-equiv=3DContent-Type><!DOCTYPE HTML PUBLIC "-//W3C//DTD W3 =
>HTML//EN">
><META content=3D'"MSHTML 4.72.3616.1301"' name=3DGENERATOR>
></HEAD>
><BODY bgColor=3D#ffffff>
><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>
>
>------=_NextPart_000_0022_01BEFB1D.4C14AF80--
>
>************************************************************************
>The RADSAFE Frequently Asked Questions list, archives and subscription
>information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html
>
>
>
>
>
>
>************************************************************************
>The RADSAFE Frequently Asked Questions list, archives and subscription
>information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html
>
************************************************************************
The RADSAFE Frequently Asked Questions list, archives and subscription
information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html