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RE: Lower limit for SCO 1 classification
I understand that SI units are now the standard, but I'm still looking to
clarify the issue of conversions and significant figures. I would venture
to say that most people use 2 nCi/g and not 1.89.
Thanks for the response. Any others?
Glen Vickers
glen.vickers@ucm.com
-----Original Message-----
From: Alan R. Marchand [SMTP:radarm@accessnv.com]
Sent: Saturday, November 07, 1998 9:23 AM
To: Multiple recipients of list
Subject: RE: Lower limit for SCO 1 classification
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look up in the 49 CFR 171.10. SI units are Regulatory standard.
Units in
parentheses are for information only and not intended to be
regulatory
standard.
Alan R. Marchand
Las Vegas, NV
radarm@accessnv.com
At 08:01 AM 11/6/98 -0600, you wrote:
>Response to this statement:
>
>Look at the definition of Radioactive material in 173.403 again. 70
Bq is
>the limit by law. This equal 1.89 nCi.
>
>
>Just how many significant figures is 70 Bq/g good for? One
significant
>figure would generate 2 nCi, not 1.89 nCi. I wonder how many
significant
>figures are applicable? Look at the DAC values in 10CFR20. They
clearly
>display only one significant figure of precision. The degree of
precision
>is not entirely clear here.
>
>Look at RQ values, the TBq values are clearly the conversion of the
standard
>Ci. The contamination limit standard appears to be 1E-5 and 1E-6
uCi/cm2
>and the conversion would be the 0.4 and 0.04 Bq/cm2 or the 22 or
2.2
>dpm/cm2. If the Bq were the standard, surely the would have chosen
>something like 0.5 Bq/cm2. When they write 0.04 they are
definitely not
>trying to imply anything more than 1 significant figure.
>
>I don't know of anyone ever being audited to 1.89 nCi/g vs 2 nCi/g.
Any
>thoughts out there?
>
>
>Sincerely,
>Glen Vickers
>glen.vickers@ucm.com
>
>
>
>
> At 02:36 PM 11/4/98 -0600, you wrote:
> >I believe NUREG 1608 explicitly states that the
contamination
>limits are
> >those on the equipment and your smears can only be a tenth
of that
>limit
> >because of the 10% smear efficiency.
> >
> >As far as lower limits go, NUREG 1608, 3.1.2. says that if
your
>material is
> ><2 nCi/g, 2200 dpm/100 cm^2 beta/gamma, and 220 dpm/100
cm^2 alpha
>then it
> >is below DOT concern. This is where the free-release
policy for
>your
> >facility comes in.
> >
> >NUREG 1608 3.1.3. says that if you have a "limited
quantity", then
>you may
> >ship as a limited quantity and not SCO.
> >
> >Sincerely,
> >Glen Vickers
> >glen.vickers@ucm.com
> >
>************************************************************************
>The RADSAFE Frequently Asked Questions list, archives and
subscription
>information can be accessed at
http://www.ehs.uiuc.edu/~rad/radsafe.html
>
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Content-Type: text/html; charset="us-ascii"
<html>
<font size=3>look up in the 49 CFR 171.10. SI units are
Regulatory
standard. Units in parentheses are for information only and not
intended
to be regulatory standard.<br>
<br>
Alan R. Marchand<br>
Las Vegas, NV<br>
radarm@accessnv.com<br>
<br>
At 08:01 AM 11/6/98 -0600, you wrote:<br>
>Response to this statement:<br>
><br>
>Look at the definition of Radioactive material in 173.403 again.
70
Bq is<br>
>the limit by law. This equal 1.89 nCi.<br>
><br>
><br>
>Just how many significant figures is 70 Bq/g good for? One
significant<br>
>figure would generate 2 nCi, not 1.89 nCi. I wonder how
many
significant<br>
>figures are applicable? Look at the DAC values in
10CFR20. They clearly<br>
>display only one significant figure of precision. The
degree of
precision<br>
>is not entirely clear here. <br>
><br>
>Look at RQ values, the TBq values are clearly the conversion of
the
standard<br>
>Ci. The contamination limit standard appears to be 1E-5
and
1E-6 uCi/cm2<br>
>and the conversion would be the 0.4 and 0.04 Bq/cm2 or the 22 or
2.2<br>
>dpm/cm2. If the Bq were the standard, surely the would
have
chosen<br>
>something like 0.5 Bq/cm2. When they write 0.04 they are
definitely not<br>
>trying to imply anything more than 1 significant figure.<br>
><br>
>I don't know of anyone ever being audited to 1.89 nCi/g vs 2
nCi/g. Any<br>
>thoughts out there?<br>
><br>
><br>
>Sincerely,<br>
>Glen Vickers<br>
>glen.vickers@ucm.com<br>
><br>
><x-tab> </x-tab><br>
><br>
><x-tab> </x-tab><br>
><x-tab> </x-tab>At
02:36 PM
11/4/98 -0600, you wrote:<br>
><x-tab> </x-tab>>I
believe NUREG 1608 explicitly states that the contamination<br>
>limits are<br>
><x-tab> </x-tab>>those on
the equipment and your smears can only be a tenth of that<br>
>limit<br>
><x-tab> </x-tab>>because
of the 10% smear efficiency.<br>
><x-tab> </x-tab>><br>
><x-tab> </x-tab>>As
far
as lower limits go, NUREG 1608, 3.1.2. says that if your<br>
>material is<br>
><x-tab> </x-tab>><2
nCi/g, 2200 dpm/100 cm^2 beta/gamma, and 220 dpm/100 cm^2 alpha<br>
>then it<br>
><x-tab> </x-tab>>is
below
DOT concern. This is where the free-release policy for<br>
>your<br>
><x-tab> </x-tab>>facility
comes in.<br>
><x-tab> </x-tab>>
<br>
><x-tab> </x-tab>>NUREG
1608 3.1.3. says that if you have a "limited quantity",
then<br>
>you may<br>
><x-tab> </x-tab>>ship as
a limited quantity and not SCO.<br>
><x-tab> </x-tab>><br>
><x-tab> </x-tab>>Sincerely,<
br>
><x-tab> </x-tab>>Glen
Vickers<br>
><x-tab> </x-tab>>glen.vicker
s@ucm.com<br>
><x-tab> </x-tab>>
<br>
>************************************************************************
<br>
>The RADSAFE Frequently Asked Questions list, archives and
subscription<br>
>information can be accessed at
<a href="http://www.ehs.uiuc.edu/~rad/radsafe.html";
eudora="autourl"><font
size=3>http://www.ehs.uiuc.edu/~rad/radsafe.html</a><br>
<font size=3>> </font></html>
--=====================_1970966==_.ALT--
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The RADSAFE Frequently Asked Questions list, archives and
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information can be accessed at
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The RADSAFE Frequently Asked Questions list, archives and subscription
information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html