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Re: FiestaWare
At 11:13 AM 6/6/96 -0500, you wrote:
>What is the primary radionuclide in FiestaWare?
>
>One of our scientists called and wanted to know.
>
>He has some of the dark orange pieces and found 0.05 - 0.1 mr/hr (~7500 cpm)
>using a geiger counter in his lab.
>
>He was concerned about the long-term "exposure" to him and his family.
>**************************** /^\ /^\ *********************************
>Tad Blanchard /__ \ /___\ NASA-Goddard Space Flt Ctr
>Nat'l Health Svc, Inc O Greenbelt, Maryland
>Sr Health Physics Tech / \ Phone: 301-286-9157
> /___\
> Tad.M.Blanchard.1@GSFC.NASA.gov
>************************************************************************
>
I have several pieces of Fiesta Ware as well as Franciscan Ware and GMB
(distinguishable from Fiesta Ware only by stamp). The orange color of these
pieces is due to uraniumoxide. As such the primary nuclides are U-238,
Th-234, Pa-234, and U-234, with trace amounts of the rest of the decay chain
depending on the efficiency of the extraction technique.
As to the reported exposures, a GM will always read higher since a great
deal of the activity is due to the beta component. I have pieces that will
give around 20 mrad/hr with a GM and only about 150 microR/hr (or rad) with
NaI(Tl) detector.
As to risk, much of the beta component is of too low an energy to penetrate
the dead layer of the skin, and is therefore of no external hazard.
Incidentally, you can also detect substantial alpha activity from Fiesta
Ware, but again, this is not an external hazard and I believe that some
studies have shown that there is no significant removable fraction of alpha
activity.
Bottom line, don't eat off of it due to potential leaching, and don't
collect a whole house full of it.
L.E. Fiske
Shepherd Miller, Inc.
Fort Collins, CO 80525
970-223-9600
Opinions are mine, but feel free to adopt them for your own.>