New Shielding material for Gammas

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Richard Hull
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Real name: Richard Hull

Re: New Shielding material for Gammas

Post by Richard Hull » Thu May 14, 2020 4:01 am

60kev gammas maybe. 2 MeV gammas gimme pure elemental lead. Light weigh means low density not good shielding for the hard stuff. No one shields hard gamma with light weigh, low density materials. There is no magic here! I am very familiar with bismuth trioxide. You mine bismuth and buy it at ~$10/lb, burn it in oxygen ($$). Mix it with plexi-glass fixins' to the desired level, UV cure it ($$). Make a nice 12"X12" plate1-inch thick for a market price of maybe $50-$80 and stop a lot of 60kev gammas. Or buy a 12"X12" plate 1/4" thick plate of lead for $10 and stop a lot of 60kev gammas. As to toxicity, I would not want to consume an LD50 piece of the new lightweight shielding or the pure lead shielding, nor would I be handling either shielding 50 times per day, 365 days per year.

Lead toxicity is a non-issue unless you are smelting it for a living each and every day. For the hyper Nervous-Nelly among us, slip your inexpensive solid lead plate into a 1/4" thick BC grade plywood sheeting box to keep yer danty little pink hands from constant daily contact if you do move your shield about 50 times during each and every day!

Bismuth is much less dense than lead. A solid metallic bismuth plate .25 inch thick will not attenuate gammas as well as a solid lead .25 inch thick plate. Now take a bismuth chemical, (a yellow powder), and disperse it in plastic and call it shielding??!! HA!

I'll be interested in finding out in all the spec sheets on the new material that the mass of new shielding needed to attenuate a given gamma ray might actually be more than for a similar chunk of pure lead plate and definitely of far greater volume. The sole advantage would come in being able to safely, and without fear, eat your scrambled eggs right on top of a 1 foot cube of the plexi-glass, Bi loaded shielding.

They are out there thinking about making big money off fear mongering to nervous-nelly types with the cash needed to be able to feel good about their shielding. Thanks for the heads up on this new marvelous super shielding product. Where can I buy some?

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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