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RE: ALARA
John:
On the contrary, I
think it leads to much needless cost and poor decisions. For example, if
there's a dirty bomb or contamination accident involving highly soluble Cs
salts, the sensible procedure would be to hose the place down thoroughly and
flush it down the drain. Current practice under ALARA is to announce loudly:
"Dilution is not the solution to pollution," and then make massive efforts to
sequester and keep all the material with detectable radioactivity in some tanks
and set up an ad hoc "hot processing facility."
The fact that tiny
amounts of radioactivity can be detected is another inherent advantage of
nuclear technology that has been turned into an unprecedented
problem.
Ted
Rockwell
Ted,
Thanks for the review. I still think that ALARA is probably a good
management to hold down cost and improve work practices, but from what you say,
it probably is not a useful for holding down insignificant doses.
Ted Rockwell <tedrock@CPCUG.ORG> wrote:
Jerry
et al:
Several people asked about the references for my ALARA quotes.
I've
excerpted some words from a recent msg I wrote that may help.
Further
specifics could be easily tracked down (e.g. the ANS statement is
PS41).
I'll help if anyone wants further info.
The original was
nicely formatted, but since we can't have attachments on
this list
(correct?), I'll cut and paste it and hope it's still
legible.
______________________________________________
Applying Realism
to Radiation Protection
Use of Cumulative Radiation Dose as a Measure
of Good Practice or of
Casualty Magnitude
NRC uses as a prime
measure of the severity of a casualty, or the efficacy
of “good plant
operation,” the total collective radiation dose in
person-rems, multiplying
trivial individual radiation doses by large numbers
of people to “predict”
thousands of induced cancer deaths. That process
has been repeatedly
described as scientifically indefensible. Yet we are
told that, in the
absence of more data, this is the prudent course. That
contention is wrong
on both counts: there is no lack of applicable credible
data and the data
show persuasively that low-dose radiation is not harmful.
The use of this
unwarranted practice continues to have serious
detrimental
effects.
NO CASE HAS BEEN MADE FOR USING COLLECTIVE DOSE
FOR PREDICTING DEATHS.
NCRP-121 does not discuss the data showing that
low-dose radiation is not
harmful, and concludes that prudence requires us
to presume harmfulness. Yet
the report concedes (p.45, emphasis
added):
Few experimental studies, and essentially no human data, can be
said to
prove, or even provide direct support for the concept…It is
conceptually
possible, but with a vanishingly small probability, that any
of these
effects could result from the passage of a single charged
particle…It is a
result of this type of reasoning that a linear
non-threshold dose response
relationship cannot be excluded.
And
NCRP-136 follows the same argument, even after stating bluntly (p. 6):
It
is important to note that the rates of cancer in most populations
exposed
to low-level radiation have not been found to be detectably
increased, and
that in most cases the rates have appeared to be
decreased.
The two major professional societies, the American Nuclear
Society and the
Health Physics Society have also supported this stance in
carefully
considered Position Statements:
It is the position of the
American Nuclear Society that there is
insufficient scientific evidence to
support the use of the Linear No
Threshold Hypothesis in the projection of
the health effects of low-level
radiation.
In accordance with the
current knowledge of radiation health risks, the
Health Physics Society
recommends against quantitative estimation of health
risks below 5 rem in
one year.
Both societies agree that:
Below 10 rem…risks of health
effects are either too small to be observed or
are
non-existent.
Regarding adding up trivial individual doses, NCRP-136
warns (p.58):
The summation of trivial average risks over very large
populations or time
periods…has produced a distorted image of risk,
completely out of
perspective with risks accepted every day, both
voluntarily and
involuntarily.
And Roger Clarke, Chairman of ICRP,
wrote (1 Oct 98 at:
http://hps.org/documents/controllable.pdf):
If the
risk of harm to the health of the most exposed individual is
trivial, then
the total risk is trivial—irrespective of how many people
are
exposed.
A practice so universally discredited should not be
used as the basis for
national
policy.
_______________________________
Ted
Rockwell
-----Original Message-----
From:
owner-radsafe@list.vanderbilt.edu
[mailto:owner-radsafe@list.vanderbilt.edu]On
Behalf Of Jerry Cohen
Sent: Wednesday, March 26, 2003 7:15 PM
To: Ted
Rockwell; Monica Oosting; radsafe@list.vanderbilt.edu
Subject: Re:
ALARA
Ted,
I know of the HPS policy statement on the subject,
but am unaware that
either ICRP or NCRP gave such advice. Could you give a
citation?
Actually, if ALARA were to apply only to doses exceeding 5.0
rem/a, it
would be unnecessary, since dose limitation rules preclude
allowance of
such exposure altogether.
Jerry Cohen
-----
Original Message -----
From: Ted Rockwell
To: Monica
Oosting
;
Sent:
Wednesday, March 26, 2003 11:23 AM
Subject: RE: ALARA
> I
believe that ALARA already has more pressure behind it than it merits.
>
Organizations are rated, in part, by how low they keep their total
>
cumulative radiation dose. This creates an incentive not to do various
>
inspections, maintenance and other necessary activities that might
result
in
> some small dose.
>
> ANS, HPS, NCRP and ICRP
have advised that ALARA should not be pushed below
5
> or 10 rem
individual dose, regardless of how many persons get such doses.
>
Ignoring such advice is counter-productive.
>
> Ted
Rockwell
>
> -----Original Message-----
> From:
owner-radsafe@list.vanderbilt.edu
>
[mailto:owner-radsafe@list.vanderbilt.edu]On Behalf Of Monica Oosting
>
Sent: Wednesday, March 26, 2003 10:20 AM
> To:
radsafe@list.vanderbilt.edu
> Subject: ALARA
>
>
>
Does anybody know if there is an industry recognized ALARA symbol?
Does
> anybody have any creative ideas on how to raise ALARA awareness
in the
> workplace? I am looking for new ideas and have not been able to
find much
> information in pamphlet or poster form.
>
>
Please email me at monica.oosting@zircatec.ca if you can help me
out.
>
> Thank you
>
> Monica
Oosting
>
>
>
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-- John
John
Jacobus, MS
Certified Health Physicist
e-mail: crispy_bird@yahoo.com
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