NukeWorker Forum
Reference, Questions and Help => Nuke Q&A => Topic started by: jonboysez on Feb 26, 2008, 04:46
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Apologies if I am in the wrong section (or even the wrong website!). I am in the UK and have just imported a Fiesta ware vintage radioactive plate from the USA (Ebay item). I have read various reports on the web on the possible dangers from this plate, from "don't worry you get more radiation from a long haul flight", to "these plates leak radon gas from cracks in the glaze which are 7 times the recommended safe level" - I have stored the plate covered with bubble wrap in the cardboard box that it arrived in and put the box in a cupboard drawer away from where I normally sit in the house. My question is - would I be better not enclosing it in a box? i.e. am I in more danger when I take it out of the packaging from trapped radon gas than if I just left it open on a work surface? Will I get a lung full of radon gas when I take it out of the packaging that could be a significant risk? I have a Russian made Krapu dosimeter and it goes well into the red when measuring the radiation on the surface of the plate.
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Okay, who is this really, and why are you yanking our collective chains?
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Just lick the plate clean of the Radon ;)
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It's not a big deal, I bought one of those as a demonstration source for some of my personal meters, just keep it nicely wrapped and enjoy!
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a suggestion - put worms in the box... and if one day the dog is missing... pack up and move out. because you are in DANGER!
How was that useful? This isn't alt.comicbooks . The poster had actual legit questions. Stay on thread or off of the Post button.
Jonboysez...if you have any concern about loose bits of radioactive material, try scanning your hands or where the Fiestaware was kept with your Russian gizmo (but you can find decent survey meters on eBay for a decent price) for increased counts. You'll have piece of mind, and start learning a bit about the wizardry here in the nuclear industry. Enjoy!
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HydroDave is 100% correct, both in his assessment of the dangers and the appropriateness of the other posters' replies.
Don't eat the plate and everything will be fine.
Edit note: The use of the word 'poser' in place of 'poster' was entirely accidental... but accurate.
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If this means anything to you here is the deal
Estimates of the Radiation Exposures
A very detailed analysis of the radiation exposures due to uranium in dinnerware can be found in the Nuclear Regulatory Commission publication “Systematic Radiological Assessment of Exemptions for Source and Byproduct Materials” (NUREG 1717).
There are three principal radiation exposure pathways associated with Fiesta Ware and other uranium containing tableware:
1. Exposure to the body from the gamma rays emitted by radionuclides in the ceramic glaze
Buckley et al reported exposure rates of 0.5 and 15 mR/hr at the surface of a dinner plate and 0.002 and 0.3 mR/hr at one meter.
The following effective dose equivalent rates were reported in NUREG-1717 for the gamma rays emitted by uranium-containing dinnerware (20 % by weight uranium):
Distance 10” Plate 3.5” Cup
1 foot 6.5 x 10-4 mrem/hr 3.7 x 10-4 mrem/hr
3 feet 7.7 x 10-5 mrem/hr 4.1 x 10-5 mrem/hr
6 feet 1.9 x 10-5 mrem/hr 1.1 x 10-5 mrem/hr
2. Exposure to the hands from the beta particles emitted by radionuclides in the ceramic glaze
Using film badges, Menczer measured beta-gamma dose rates of 0.5 to 20 mrad/hr on contact with various items of glazed ceramic dinnerware. He calculated that the hands would receive approximately 2 to 10 rem per year as a result of handling such dinnerware 1.5 hours per day.
Piesch et al. measured 32 mrem per hour at the surface of a red ceramic teacup. Assuming daily use of the cup, they estimated an annual dose to the lips of 400 mrem and 1200 mrem to the fingers.
NUREG-1717 calculated the beta dose rates at a depth of 7 mg/cm2 (i.e., the nominal depth of the germinal layer of the skin) as well as the estimated effective dose equivalent. It was assumed that the source was a 10 inch diameter plate with a 20 % by weight uranium content.
Distance Dose Rate Effective Dose Equivalent Rate
Contact 24 mrad/hr 0.0024 mrem/hr
1 foot 0.84 mrad/hr 0.0021 mrem/hr
3 feet 0.089 mrad/hr 4.5 x 10-4 mrem/hr
The ratio between the effective dose equivalent rate and dose rates vary with distance because the further away from the source, the greater the area of skin that was exposed.
3. Ingestion of uranium that has leached into food that has been in contact with the ceramic glaze
Kendig and Schmidt measured uranium concentrations of 1.8 to 8.6 ppm (0.6 x 10-6 to 2.9 x 10-6 uCi/ml) in acetic acid that had been in contact with red glazed ceramic dinnerware for 24 hours. The range of concentrations went up to 41 to 51 ppm (1.4 x 10-5 to 1.7 x 10-5 uCi/ml) for 60 hours of contact.
Landa and Councell measured uranium concentrations of 3.9 to 10.6 ug/liter (1.3 x 10-9 to 3.5 x 10-9 uCi/ml) in water, 470 to 31,800 ug/liter (1.6 x 10-7 to 1.1 x 10-5 uCi/ml) in acetic acid, and 96,100 to 304,000 ug/liter (3.2 x 10-5 to 1 x 10-4 uCi/ml) in nitric acid. In each case, the solutions had been in contact with the dinnerware for 24 hours. Landa and Councell noted that repeated exposure to these solutions resulted in a reduced leaching of uranium.
Based on the above leaching rates for 24 hour contact periods, NUREG-1717 estimated that an individual using nothing but this type of dinnerware might consume 0.21 grams of uranium per year. Then, using an ingestion dose factor of 1.9 x 10-4 mrem/ug, NUREG-1717 estimated that such an individual might have an effective dose equivalent of 40 mrem per year. This was the highest dose calculated in any of the exposure pathways considered by NUREG-1717.
hope that helps mate
sf
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How was that useful? This isn't alt.comicbooks . The poster had actual legit questions. Stay on thread or off of the Post button.
sorry hydro.
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Many thanks for the sensible replies.......
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I just bought a Fiestaware plate several months ago for the home collection of various rad materials. I've always wanted to take a frisker to an antique store.
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I'm afraid to know what my wife has in those cabinets. Her grandmother left her a lot of pink and orange glass. Some of it is lead-crystal. Some Uranium. Our Fiestaware (our everyday dishes) came from Macy's and have no Uranium as far as I know.
The Fiestaware factory is not far from Beaver Valley - just down the road in WVa. Maybe somebody ought to borrow an rm14 and take a drive down to their outlet store.
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Yikes might wannna move BeerCourt ;) But probably ok since its near one of those dangerous Nuklear plants :o
Some info on timelines for those with an interest
The red color was achieved by adding uranium oxide in the glaze - measurements have indicated that by weight, up to 14 % of the glaze might be uranium. How much glaze was employed per plate is unclear but it has been estimated that a single plate contains 4.5 grams of uranium (Buckley et al). Piesch et al estimated the glaze thickness at 0.2 mm.
Since this uranium could be used in the production of an atomic bomb, Fiesta red became a victim of World War II when the US government confiscated the company’s stocks of uranium. Fiesta red disappeared until 1959 when production resumed, this time using depleted uranium (DU) rather than the original natural uranium. The Fiesta red plate in the above photo was made from depleted uranium while the ivory plate was made from natural uranium.
In 1969 the entire Fiesta ware line was discontinued, and in its place the company produced what was known as Fiesta Ironstone. The latter, which was only manufactured in Fiesta red (aka Mango Red), didn’t last long. It was discontinued in 1973. This was the end of Fiesta red. Years later, in 1986, a new line of Fiesta ware was introduced but without the red color.
1936 – 1943 Fiesta red was produced using natural uranium
1959 – 1969 Fiesta red Fiesta Ware was produced using depleted uranium
1969 - 1973 Fiesta red Fiesta Ironstone was produced using depleted uranium
It is worth noting that the use of uranium to produce a red ceramic glaze was not limited to Fiesta ware. Almost any antique ceramic with a deep orange/red color is likely to be radioactive, e.g., that produced by the Bauer Pottery Company. In addition, various manufacturers, including the Homer Laughlin Company, have used uranium to give their ceramics other colors, e.g., yellow, green, brown. Buckley et al estimated that 2 million pieces of dinnerware between 1959 and 1969 that employed uranium containing glaze.
As a footnote Ill add an observation that some fossils (no I dont mean us old farts) contain sometimes up to 3000 cpm of activity mainly due to Ra226 especially fossils that were formed underwater or at a time when the area was underwater.
sf
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Yah when I went through Radworker training our instructor had a fiesta plate like the one jonboy got off of ebay. There is no danger in the thing unless you use it as a pillow, or carry it around with you for 24 hrs a day 7 days a week. I dont recall every reading anywhere that some one died from over expsure to the stuff. They are safe as can be, besides they kept the food warmer longer.