Richard Mahaffey on fri 6 apr 01
Hello All,
One of the Chemistry teachers at school asked me a question about the
use of uranium in glazes. He was wondering if anyone used it and if
there were any legal questions. The safety questions are obvious. The
uranium in question is depleted uranium. I d not know the exact
chemical state of it. We were just talking about glazes and such. We
do have a couple of yellow Fiesta ware plates that are used in a
radioactivity demonstration with a Geiger counter.
Any help would be appreciated and also any specifics regarding
legalities and/ or safety that are backed up by knowledge would be
appreciated.
Thanks in advance.
Rick Mahaffey
Tacoma Community College
Tacoma, Washington, USA
Rick Monteverde on sat 7 apr 01
Rick -
I know it's illegal to sell. I doubt (don't know for sure) if it's
illegal to try it at home, but I sure wouldn't.
I like to fool around with odd things sometimes, and I've been
tempted to try some experiments which take advantage of some uranium
compound's ultra-high dielectric capacity along with its high mass.
But so far I've steered clear, and I wouldn't even think of using
uranium in a glaze. DU is inert and quite safe as a bulk solid (like
your Fiesta ware or my Vaseline Glass pieces) - but as dust or vapor
it can be very dangerous. Ask the Gulf War vets with crippled immune
systems. Don't drop those plates!
- Rick Monteverde
Honolulu, HI
>Hello All,
>
>One of the Chemistry teachers at school asked me a question about the
>use of uranium in glazes. He was wondering if anyone used it and if
>there were any legal questions. The safety questions are obvious. The
>uranium in question is depleted uranium. I d not know the exact
>chemical state of it. We were just talking about glazes and such. We
>do have a couple of yellow Fiesta ware plates that are used in a
>radioactivity demonstration with a Geiger counter.
>
>Any help would be appreciated and also any specifics regarding
>legalities and/ or safety that are backed up by knowledge would be
>appreciated.
>
>Thanks in advance.
Gary Cox on sat 7 apr 01
I was near Memphis visiting a potter in the sticks and remarked at his wonder ^10
reds. He said it was uranium that he dug up. Back at school, I found a friendly
science guy who ordered enought for a test. I had to answer a bunch of questions
from government folks about how I was going to use the stuff and eventually my
determination just peetered out. I just can't forget those wonderful hues, so
include me in this thread
Richard Mahaffey wrote:
> Hello All,
>
> One of the Chemistry teachers at school asked me a question about the
> use of uranium in glazes. He was wondering if anyone used it and if
> there were any legal questions. The safety questions are obvious. The
> uranium in question is depleted uranium. I d not know the exact
> chemical state of it. We were just talking about glazes and such. We
> do have a couple of yellow Fiesta ware plates that are used in a
> radioactivity demonstration with a Geiger counter.
>
> Any help would be appreciated and also any specifics regarding
> legalities and/ or safety that are backed up by knowledge would be
> appreciated.
>
> Thanks in advance.
>
> Rick Mahaffey
> Tacoma Community College
> Tacoma, Washington, USA
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
Stephani Stephenson on sat 7 apr 01
Rick
You might want to consult some of the glassblowers up your way about
uranium.
I knew a friend who used it, though I don't remember the details about
how, where he got it.
I do remember his pieces, which glowed in the dark.
He used it while at Alfred. Maybe another source of information on
current regs, hazards, etc.
Though not commonly used, seems like uranium use is not unheard of
by today's glassblowers.
possibly used more by them than by today's potters.
Stephani Stephenson
Leucadia CA
Joseph Herbert on sun 8 apr 01
Richard Mahaffey wrote:
“He was wondering if anyone used it and if there were any legal questions.
The safety questions are obvious. The uranium in question is depleted
uranium”
I am not sure that it is legal for anyone in the U.S. to own uranium. I
think it may be true that all uranium is owned by the government and any
holding of it is on a licensed basis. When you possess uranium and other
radioactive materials, you are required to have a license with the NRC and
to account for the material on a regular basis.
This was certainly not true when uranium was used in ceramic glazes and
smoked glass. At that time, (1920’s 1930’s) there was no particular use for
uranium other than this. It was sort of a byproduct to radium refining, a
material with limited ceramic use. At any rate, a different use was found
for uranium and it became the province and property of the U.S. government.
It the time when uranium was used as a ceramic colorant, it was not in any
sense “depleted.” It was natural and contained all the stuff that
chemically separated uranium might contain. It was pretty radioactive. Not
like radium, but kind of hot. Once the U.S. government found a use for both
common isotopes of uranium, the gigantic physical process of separating the
isotopes was undertaken. At this time it became possible for uranium to be
“Depleted.” The vast gas cascades at Oak Ridge, TN separated uranium into
some that was nearly all U235 and lots more that was nearly all U238.
The U235 is atomic bomb making material and is also the basis (at low
concentrations) for all current commercial nuclear power. U238 is a
slightly radioactive metal that, when exposed to lots of neutrons, changes
into plutonium 239. Plutonium239 is atomic bomb making material. In a
chemical process that took place at the Hanford reservation in Washington
State, the plutonium was separated from the U238 and both the U238 and the
Pu239 are recovered. This U238 is also “depleted.” Its life history,
however, is very different than the U238 that comes from ore and goes
through the physical separation of isotopes. The U238 from the ore has no
possibility of fission products being present (there is one rare exception).
The U238 from plutonium production or any reactor fuel reprocessing could
contain some fission products, depending on how good the chemical separation
that reclaimed it was. In any event, saying the Uranium is, “depleted”, may
not tell the whole story as the people at the Paducah Gaseous Diffusion
Plant have found to their sorrow.
Indeed, to say that the safety hazards are obvious isn’t so. You may not
really know what your “uranium” contains. Most of the dangers from uranium
and other radioactive materials result when the person who comes in contact
with it is uninformed and unprepared. Certainly a person has a right to
expect that his tableware is not radioactive. Actually, that is kind of
impossible since potassium 40 is naturally occurring and is present
everywhere, even inside us. Leaving that aside, any extra, intentionally
added radioactivity is a bad thing and probably illegal in the U.S.
While there are probably ways to get uranium, stealing Abrams M1A1 armor
piercing rounds is one way, my question is: Why? It is a lot of trouble for
a ceramic result that may be attainable in other ways.
Joseph Herbert
Tom Buck on sun 8 apr 01
Rick M:
I do not know the legal standards for depeleted Uranium, hopefully
Monona Rossol does and she will respond.
What is depleted Uranium (element No. 92)? It is the "leftovers"
when Uranium (as Uranium Hexafluoride) is processed through a gaseous
diffusion works (Oakridge TN, USA, and others). Two "streams" are produced
by this works, one is "enriched uranium" (converted to the oxide) to serve
as fuel for the USA nuclear power (fission) plants; the other stream
becomes depleted Uranium (usually as metal sometimes as a compound).
Natural uranium fed to the works has two key fissiles: the U235
and U238 isotopes. U235 fissions more readily than U238, so it is the
desireable fissile for the nuclear reactor (either GE or Westinghouse
types). Natural U contains 0.714 weight per cent U235, and the enrichment
has to go to approx 3.5%w U235 for reactor fuel. Which leaves the depleted
Uranium with approx. 0.3%w U235, the rest U238.
When either isotope undergoes fission inside a reactor, it splits
into two parts and also releases 2 or 3 neutrons. The new daughter
elements have a broad range of atomic weights, some of which are
radioactive.
Outside the reactor, depeleted U will change slowly, releasing
"alpha particles" (helium atoms without electrons); very infrequently a
U235 atom will fission, making daughter elements. Alpha particles become
dangerous if somehow the very dense depleted U metal or compound were
inhaled (less so when ingested).
Fiesta ware contains natural Uranium, and it poses a hazard if
constant contact is made with say a plate or a bowl -- the alpha particles
may affect the skin, etc. But a plate hanging on the wall would have
little to add to "background radiation", the radioactivity of the
universe we experience every day and survive.
til later. peace. Tom B.
Tom Buck ) tel: 905-389-2339 (westend Lake Ontario,
province of Ontario, Canada). mailing address: 373 East 43rd Street,
Hamilton ON L8T 3E1 Canada
Gavin Stairs on sun 8 apr 01
At 03:18 PM 4/8/01, Tom Buck wrote:
>Rick M:
> I do not know the legal standards for depeleted Uranium, hopefully
>Monona Rossol does and she will respond.
There is no legal definition of depleted uranium. It is, as you state,
what is left over when the economic limit of "useful" U235 is
extracted. Please note that not all the U235 is extracted. Perhaps 50%
may remain. That means even the best DU is not as inert as most people assume.
A lot depends on where the feedstock came from, and how long it has been
stored since refining. If it is chemically pure uranium, then your outline
is more or less true, until the daughters are all restocked. If it is
natural uranium, with its daughters, then the activity of the depleted
uranium is somewhat higher, since the unstable daughters are also
active. If it comes from spent fuel, then it may contain all sorts of
fission products, many of which are quite active. It is naive and
dangerous to assume that depleted uranium is inactive material. It is also
naive to assume that depleted uranium emits only alpha. Quite a few betas
and gammas around 1Mev are also emitted.
The only sources of DU are the stockpiles of the nuclear industry. In the
US, that means the Oak Ridge Y12 facility and others like it. DU is stored
there as metal pigs and other forms, and it is used principally by the arms
industry to make armour, counterweights and anti-armour munitions. The
feed stocks are natural uranium and spent fuels. In general, these DU
stocks are not available to foreigners, but special "loans" have been
arranged for some research uses. I don't know if this material is for sale
to US citizens, but if it is, it will certainly come with a heavy reporting
and regulatory surcharge. In Canada, we have access only to natural
uranium. I've never tried to buy any as an individual. I would expect it
to be difficult, and to carry the same reporting baggage. One would need a
licence, etc. That said, there are certainly small amounts of this
material circulating outside the regulatory framework. This is presumably
the source of most, if not all, the material on offer for use in
potteries. Thus it is certainly extra-legal, if not illegal.
The greatest risk in the use of uranium is to the potter/processor, who may
inhale dust particles in the dangerous size range. This raises a
persistent irradiation danger in the mucosa of the lungs and respiratory
tract. In the form of a finished article, it is less dangerous, and is
possibly negligible, unless you were to sleep on it, or otherwise live in
close proximity to it.
The nuclear industry is required to employ many monitoring and safety
measures in its processing plants. These are generally infeasible for
studio potters, so potters will tend to be at greater risk than industrial
radiation workers for the same type of exposure. Then there are the
environmental risks. Port Hope, Ontario, is now facing an extensive
clean-up problem after having hosted AECL for many years. Apparently the
soil of the city is quite generally contaminated.
Uranium is a common contaminant in many soils and rocks. However,
ore-grade outcrops are much rarer. I would be a bit skeptical of just
finding useful concentrations of uranic soils lying about. I'd also feel a
bit strange about living next to them. There are a few places in Canada
where people live on outcrops with radiation levels several times ordinary
backgrounds, without, so far as I know, any adverse health effects. But I
would not like to live on the Elliot Lake tailings pile, for example.
The risks of radiation materials like this in small amounts is relatively
slight, but well disguised, like smoking. You won't just drop dead one
day. It will creep up slowly, and you may one day find yourself with lung
cancer, or something like that. If you were to walk through a cloud of
dust, breathing deeply, the effect might be more dramatic. Or you could
get lucky.
Please be careful with this stuff. An accident with it could land you in
serious trouble. If you choose to use it, please take precautions against
breathing dust while handling the material, and take extra precautions to
make sure you don't track it all over the house on your clothing.
Gavin
Gavin Stairs
Stairs Small Systems
1A - 921 College Street
Toronto, Ontario, Canada M6H 1A1
phone: (416)530-0419 stairs@stairs.on.ca
isak@mbox303.swipnet.se on mon 9 apr 01
Hallo all,
About uranium........
I=B4v been working with uraniumoxide (the yellow powder) on and off for =
20 years and
every year when i go to my "yearly medical inspection" of my healt we =
always talk about
the materials i work with, among them uranium and lead.
This parts are of course extremely toxic and to work with them is not a =
problem as
long as i know what i=B4m dealing with. Rubber-glowes, mask and =
eye-shield and i am
never present in the studio while i=B4m firing this kind of glazes.
Altough i can feel a "little bit crazy" doing this, but as many of you, =
working with clay
and glazes for many years, sometimes need to challenge your skill and =
the parts that are
a little bit strange.
A couple of days ago i got a request from a collector in Florida who =
whanted to bye one of
the uranium-crystal-pieces from my homapage. I talked to the Swedish =
goverment about sending
a uranium-glazed piece to US and they said that it should=B4nt be any =
problems but the could=B4nt
say if there should be any problem with the US-custom.......
Still healty-
All the best
Isak Isaksson
Velamsund
SE13236 S-Boo
Sweden
Ph:(+46) 8 747 97 21
www.swedcrafts.nu
isak@swedcrafts.nu
----- Original Message -----=20
From: "Cindy Strnad"
To:
Sent: Monday, April 09, 2001 2:09 AM
Subject: Re: hazards in using Uranium (fwd)
> Just another note on the uranium thread. I haven't been following it,
> however, in case this hasn't been mentioned, uranium, were you to find =
a
> completely depleted source (if that's possible), still has the same =
sort of
> toxicity as lead.
>=20
> Cindy Strnad
> Earthen Vessels Pottery
> RR 1, Box 51
> Custer, SD 57730
> USA
> earthenv@gwtc.net
> http://www.earthenvesselssd.com
>=20
> =
_________________________________________________________________________=
_____
> Send postings to clayart@lsv.ceramics.org
>=20
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>=20
> Moderator of the list is Mel Jacobson who may be reached at =
melpots@pclink.com.
evan on wed 11 apr 01
There are some things I disagree with in this. My comments are
interspersed below.
Gavin Stairs wrote:
>
> At 03:18 PM 4/8/01, Tom Buck wrote:
> >Rick M:
> > I do not know the legal standards for depeleted Uranium, hopefully
> >Monona Rossol does and she will respond.
>
> There is no legal definition of depleted uranium. It is, as you state,
> what is left over when the economic limit of "useful" U235 is
> extracted. Please note that not all the U235 is extracted. Perhaps 50%
> may remain. That means even the best DU is not as inert as most people assume.
You are probably right that there is no legal definition of depleted
uranium. The conventional definition is uranium which has been
processed so that the uranium-235 content is lower than the natural
isotopic abundance. It is important to note that this processing will
reduce the abundance of uranium-234 also. This is important.
According to Fetter and VonHippel (Science and Global Security v. 8:2
pp. 125-161, 1999) the composition of uranium is:
Natural Depleted
wt. % wt. %
U-234 0.0054 0.0007
U-235 0.711 0.2
U-236 0 0.003
U-238 99.28 99.8
They state that the uranium-235 of depleted uranium (DU) can range up to
0.3 percent but the DU used by the US Dept. of Defense is about 0.2%. I
think it is perfectly reasonable to use these numbers when looking at
the risks.
The uranium-235 content has almost no relationship to the hazard of the
uranium. For natural uranium only 2% of the dose for ingestion comes
from uranium-235. 54.2% of the dose comes from uranium-234 and 43.8%
from uranium-238. So really this idea that depleted uranium is rendered
harmless by removing the uranium-235 is incorrect. What does happen is
that removing the uranium-234 reduces the radioactivity significantly.
But even in the best of cases you will still be left with nearly half
the dose because of uranium-238 alone.
> A lot depends on where the feedstock came from, and how long it has been
> stored since refining. If it is chemically pure uranium, then your outline
> is more or less true, until the daughters are all restocked. If it is
> natural uranium, with its daughters, then the activity of the depleted
> uranium is somewhat higher, since the unstable daughters are also
> active. If it comes from spent fuel, then it may contain all sorts of
> fission products, many of which are quite active. It is naive and
> dangerous to assume that depleted uranium is inactive material. It is also
> naive to assume that depleted uranium emits only alpha. Quite a few betas
> and gammas around 1Mev are also emitted.
Uranium whether purified from natural uranium or purified and then
depleted by isotopic separation has the daughters removed in the
chemical separation process. Some uranium was recovered from spent fuel
in the weapons programs and I suppose in the reprocessing of fuel that
is done in Europe (including Janet's neighborhood). In this process you
had better believe that nearly all the fission products are removed.
Otherwise there is no way anyone could handle it. Most likely traces of
technetium-99 remain in the recovered uranium because their chemistry is
similar. The traces of uranium-236 in DU show that some uranium from
reprocessed fuel made it into the supply because that is the only way
uranium-236 is formed.
When uranium metal sits around after purification, the first two
daughters in the decay chain, thorium-234 and protactinium-234 grow back
in rapidly because they have short half-lives (24.1 days and 1.17
minutes, respectively) Then next daughter is uranium-234 which is
already there. The daughter of uranium-234 is thorium-230 which has a
very long half life (75,400 years). It takes several half-lives for the
concentration to build up to the amount found in nature. For all
intents and purposes, you can neglect thorium-230 and its daughters
because of this. So no, the daughters will not be "restocked" in any
reasonable time period (unless you happen to be a geologist).
Bottom line: depleted uranium is not inactive but that has little or
nothing to do with the reasons Gavin stated. My conclusion from all
this is that it makes little difference if you are using natural or
depleted uranium -- maybe a bit less than half the risk from radiation
if it is depleted uranium. And in the business of calculating risk they
tend to work in order of magnitude estimates (factors of ten). Don't
forget that the chemical risk from ingestion is likely as important as
the radiation risk. I'm not going to tell anyone it is or isn't ok to
use uranium in your glazes. I will say that, like any other chemical we
use, we need to be informed as best we can and decisions should be based
on facts & the best science available.
Well, I'm pooped. I'm going to snip off the rest and stop here. I'll
just add that I agree with Gavin that the greatest radiation risk would
come to the potter from inhalation of fine particles. I hope this
helps.
-- Evan who learns something every time this subject comes up.
Gavin Stairs on thu 12 apr 01
At 08:45 PM 4/11/01 -0700, Evan Dresel wrote:
>There are some things I disagree with in this. My comments are
>interspersed below.
Hi Evan,
Just a few comments:
1. All the DU I have played with (about 100 tons from Y12) had U235
content in the region of 0.5%
2. My comments re: the trace contents of other nasties come from the
people who live with this stuff. They spoke of stuff they called
garbonium, because of its high fission byproduct content. Mind you, they
didn't give us any of that.
3. The Y12 people would not guarantee the analysis of the material, as
they had a wide range of metal in inventory, and they were not completely
sure about the source of each pig.
4. Every time I see precise analyses quoted concerning these materials,
accompanied by a learned argument, I simply recall these points, and sigh.
5. It is dangerous to rely on assumptions when your assumptions lead you
to reduce the estimate of radiation risk.
6. I'm going to stop now. Some people just want to play with
Uranium. That's ok by me. I'll steer well clear of those studios. And I
won't drink from mugs with bright orange glaze.
Gavin
Gavin Stairs
Stairs Small Systems
1A - 921 College Street
Toronto, Ontario, Canada M6H 1A1
phone: (416)530-0419 stairs@stairs.on.ca
ACTSNYC@CS.COM on fri 13 apr 01
>
> ---------- Forwarded message ----------
> Date: Wed, 11 Apr 2001 20:45:18 -0700
> From: evan
> Reply-To: Ceramic Arts Discussion List
> To: CLAYART@LSV.CERAMICS.ORG
> Subject: Re: hazards in using Uranium
>
> There are some things I disagree with in this. My comments are
> interspersed below.
>
> Gavin Stairs wrote:
> >
> > At 03:18 PM 4/8/01, Tom Buck wrote:
> > >Rick M:
> > > I do not know the legal standards for depeleted Uranium,
> hopefully
> > >Monona Rossol does and she will respond.
SNIP
Evan, in this post, said everything you need very well and very completely.
Print it out and keep it. I would just summarize some major points for people
to remember when this comes up again--as it always does.
1) All isotopes of uranium are radioactive--not just U235.
2) U235 is removed because it has the right number of neutrons to support a
fission reaction--not because of its radioactivity.
3) U235 is one of the most radioactive compounds so that after most of it is
removed, the remaining "depleted" uranium is somewhere between 40 and 50% as
radioactive as the original uranium mixture of isotopes.
4) Even more important than radioactivity is the high toxicity of the
uranium. It is a potent kidney toxin.
5) Find another colorant.
Monona Rossol
ACTS
181 Thompson St., #23
NYC NY 10012-2586 212/777-0062
ACTSNYC@cs.com
evan on sun 15 apr 01
A clarification:
Uranium-235 is far from being one of the most radioactive compounds. It
has a very long half-life (704,000,000 years) just not as long as
uranium-238 (4,470,000,000 years). There are a great many naturally
occuring and man-made isotopes that are more radioactive.
Uranium-234 is far more radioactive than uranium-235. There is less
uranium-234 by weight than uranium-235 in natural uranium but it
produces about half the total radioactivity. Only a tiny amount of the
radioactivity in depleted or natural uranium (or enriched uranium for
that matter) is from the uranium-235. The uranium-235 *doesn't matter*.
Here's the catch: When they enrich uranium to increase the uranium-235
it is also enriched in uranium-234. The left over depleted uranium is
also depleted in uranium-234. That's what makes the major part of the
difference in radioactivity between depleted and natural uranium.
So to re-reiterate: The uranium-238 provides close to half the
radiation dose. So no matter how depleted the uranium is, the remaining
depleted uranium is still radioactive.
Is it too risky to use? If you aren't quite sure, you should probably
believe the people telling you to leave it alone.
-- Evan in W. Richland who is a bit sore from putting in fence posts.
Almost done.
ACTSNYC@CS.COM wrote:
>
> >
> > ---------- Forwarded message ----------
> > Date: Wed, 11 Apr 2001 20:45:18 -0700
> > From: evan
> > Reply-To: Ceramic Arts Discussion List
> > To: CLAYART@LSV.CERAMICS.ORG
> > Subject: Re: hazards in using Uranium
> >
> > There are some things I disagree with in this. My comments are
> > interspersed below.
> >
> > Gavin Stairs wrote:
> > >
> > > At 03:18 PM 4/8/01, Tom Buck wrote:
> > > >Rick M:
> > > > I do not know the legal standards for depeleted Uranium,
> > hopefully
> > > >Monona Rossol does and she will respond.
>
> SNIP
>
> Evan, in this post, said everything you need very well and very complet=
ely.
> Print it out and keep it. I would just summarize some major points for =
people
> to remember when this comes up again--as it always does.
>
> 1) All isotopes of uranium are radioactive--not just U235.
>
> 2) U235 is removed because it has the right number of neutrons to supp=
ort a
> fission reaction--not because of its radioactivity.
>
> 3) U235 is one of the most radioactive compounds so that after most of =
it is
> removed, the remaining "depleted" uranium is somewhere between 40 and 5=
0% as
> radioactive as the original uranium mixture of isotopes.
>
> 4) Even more important than radioactivity is the high toxicity of the
> uranium. It is a potent kidney toxin.
>
> 5) Find another colorant.
>
> Monona Rossol
> ACTS
> 181 Thompson St., #23
> NYC NY 10012-2586 212/777-0062
>
> ACTSNYC@cs.com
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