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When I
worked in a uranium mine we always calculated J/m3 (or should i say micro J/m3).
It is a simple matter to include the conversion factor for WL to J/m3 into the
calculation. Basically the calculation involves counts, detector efficiency
and a "factor". This "factor" is a single number that takes into account sample,
decay and counting times, volume collected among other times like the number
that converts WL to J/m3. I guess the calculation used by the technicians should
have been updated.
I believe the HPS once endorsed J/m3 for WL
and Jh/m3 for WLM. Of course, h is not an SI unit (even though its use is
still permitted) and the correct unit should be Js/m3. People get paid by the
hour, not by the second, so Js/m3 is not very convenient.
A while ago, it looked like Canada was going to
adopt SI units and we once wrote an entire EIS in J/m3 and Jh/m3. It is easy
to do theoretical calculations in those units. The problem is that the
technicians on the ground don't have any means of measuring J/m3.
They collect radon progeny on a filter and then count the activity
in a portable counter. The formulas that they use for converting the counts to
airborne activity either have never been converted to produce J/m3, or the
converted formulas have not been widely distributed and the regulatory
agencies have not given their stamp of approval on the formulas.
The technicians would therefore have to calculate
the airborne radiation in WL and then convert it to SI units. This defeats the
purpose of adopting SI units, which is to make things simpler.
The SI units for radon progeny never caught on
and we ended up converting the predictions back to WLM. [And yes, there
were some conversion mistakes, but of course these happened after I quit the
company :).]
My guess is that WL will be one of the last
things to get converted to SI, but they will get converted.
Kai
----- Original Message -----
Sent: Tuesday, April 08, 2003 8:17
AM
Subject: Re: Bq soon
This is the best posting I've seen on this subject. I
remember the top down, "Do it my way or else..." campaign in the
1970's. My facility had a full time, "metrification
coordinator." I was reprimanded for not supporting metrification
with sufficient enthusiasm. That, more than anything, is what turned
me against SI units.
Regarding "Working Levels." - If there was ever a unit that needed to be
SI'd, this is it. On the other hand, I think that most persons, other
than those who earn a living from Rn testing and remediation, agree that
this is a solution looking for a problem, EPA scare ads notwithstanding.
The opinions expressed are strictly mine.
It's not about dose, it's
about trust.
Curies forever.
Bill Lipton
liptonw@dteenergy.com
mark.hogue@SRS.GOV wrote:
I think
Bjorn gave us the best flavor of what it takes to get used to a
system.
The reason it's taking so long for
the US to go metric is because the big push in the '70's (when I was in
grade school) was such a flop. Instead of trying to give everyone a feel
for the 'new' units, we were told, hey, look, an inch is 2.54 centimeters
and a gallon is 3.7854 liters! No problem! Here's a table for you to
memorize. Naturally, that made no sense to anyone. Plus, manufacturers
objected to the real cost: retooling factories for metric sizes on nuts
and bolts, etc.
Now, I have to think we've come a
long way. Most people who use wrenches have already bought a metric set
and maybe wish they wouldn't have to keep the english set
too.
By the way, for radon measurements,
is there anything metric that captures the real meaning of a working
level?
Mark G. Hogue, CHP
mark.hogue@srs.gov
"But we surely overrate the
usefulness of what we like to call "stimulation" and underrate the need
for time, peace of mind, mature reflection." - Susan
Haack
"DISCLAIMER: The opinions expressed
are mine and do not necessarily represent Westinghouse Savannah River Co.
or the United States Department of Energy."
This e-mail is intended for the addressee(s) named and may contain confidential and/or privileged information. If you are not the intended recipient, please delete it immediately and notify the sender. Any views expressed in this email are those of the individual sender except where the sender expressly and with authority states them to be the views of the Environment Protection Authority.
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