RE: background vs man-made emissions

["Franta, Jaroslav" <frantaj@aecl.ca>]

The subject name of this thread reminds me of the "Hands-on Radiation
Workshop" we did here in Chalk River just last Thursday, for a busload of
teachers from across the country (Canada that is).

I happened to be doing the Wilson cloud chambers demo, which is very popular
with all who haven't seen it yet (and the equipment needed is so simple,
that many teachers come away with plans to do them in their school science
or physics classes..  ...while those few that have done it are keen to learn
why theirs didn't work).

ANYHOW, at one point I remarked to a particularly fascinated teacher who
just kept staring at the "fireworks," to "now just think that its going to
keep doing that for the next ten billion years" (it was a small piece of
natural uranium - with its usual decay chain products, of course).
But then I quickly added "...unless of course we burn it up in a nuclear
reactor and turn it into fission products with halflives ranging mostly from
a few days to a few years."

I'm not sure if my remark sank in, but its similar to what Vincent.King said
on Monday May 01, 2000 3:51 PM :

>      What would we have if EVERY easily accessible uranium atom was 
>      fissioned in a power plant (including U-238 atoms converted to 
>      plutonium and then fissioned as well)?  We would have:
>      
>      (1) relatively short-lived radioactive decay products (many of 
>      which are useful resources themselves),
>      
>      (2) no more plutonium (and therefore no more proliferation 
>      concerns), and
>      
>      (3) thousands of years of energy that created no carbon dioxide in 
>      the process (for those who are concerned with carbon dioxide 
>      generation).
<><><><><><><><>

....I also like Don Kosloff's lightbulb analogy (Sunday April 30, 2000 5:24
PM) -- but find it particularly useful in explaining the inverse
relationship between radioactive intensity and halflife. Most lay people are
totally clueless about this, and think that short is "good" and long is
"bad."
My analogy is an electric battery of fixed capacity, to which you connect
lightbulbs of varying sizes...
...the tiny model railroad train lightbulb will shine feebly for a year,
while a football stadium floodlight connected to the same battery will blaze
for a fraction of a minute & die out (the integrated "dose" is the same,
etc. etc.).

Just need to remember to say these things at every opportunity, I guess.

Jaro
frantaj@aecl.ca




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