putting together a gamma spectrometer (using soft MCA)

[Sigurthr]

It's really not as dangerous as the public perception of it is. Pretty much as long as you follow one basic guideline: all home rad materials must be non-dispersible, you don't even have to worry about contamination (the single largest threat) as long as you follow normal handling guidelines.

Once you understand how it works, what it is, and how to treat it, it isn't scary anymore. For example I have a 320g ingot of machined highly purified U238 that I keep as a curio and checksource. It stays on my desk just about 2ft away from me. I'm having a lead pig worked on so that I can sequester it away to not disturb sensitive measurements, but even totally exposed it presents no real threat to my health. It radiates about 40mR/hr on contact (iirc, I'd have to check my notes) which makes it very "hot" by home rad standards, yet at a distance of 2ft the exposure of ten hours continuous is less than one hour of being on a passenger airplane.

 

[ped]

Yeah, I suppose it like a lot of things, follow the recommended guidelines, use a bit of common sense and you should be ok.

I can't say I'd like to a some U238 sitting on my desk though .

 

[paul1598419]

It's really not as dangerous as the public perception of it is. Pretty much as long as you follow one basic guideline: all home rad materials must be non-dispersible, you don't even have to worry about contamination (the single largest threat) as long as you follow normal handling guidelines.

Once you understand how it works, what it is, and how to treat it, it isn't scary anymore. For example I have a 320g ingot of machined highly purified U238 that I keep as a curio and checksource. It stays on my desk just about 2ft away from me. I'm having a lead pig worked on so that I can sequester it away to not disturb sensitive measurements, but even totally exposed it presents no real threat to my health. It radiates about 40mR/hr on contact (iirc, I'd have to check my notes) which makes it very "hot" by home rad standards, yet at a distance of 2ft the exposure of ten hours continuous is less than one hour of being on a passenger airplane.

This is true. Now if it were an ingot of U235, that would be a much different proposition. In fact U238 that is used for nuclear reactions are artificially enriched to have a greater amount of U235 than the 0.7% of natural U238. A pure ingot of U238, that is devoid of U235 is safe because of the lack of U235.

 

[Sigurthr]

Yup! I've got a 10" fiestaware dinner plate that is glazed with NatU (0.7% U235) and it has a higher surface contact emission than my ingot. It's also a much larger field due to geometric differences. There's maybe 20g of uranium total in it, so maybe 140mg of U235. I wouldn't eat off of it for fear of contamination when scratching the glaze, but even with its increased emission it isn't hazardous to be around.

 

[paul1598419]

It is maybe safe with such a small amount of U235, but don't forget about the many people who have worked on sites that purify uranium and have gotten cancers and worse from long time exposure. It is not an innocuous substance. The Curies died early from their exposure to radioactive elements and many have died outright from radiation poisoning.

Edit: It was actually Marie Curie who died of aplastic anemia at age 67 from exposure to radiation. Pierre died at age 46 from an accident.

 

[Seoul_lasers]

This is true. Now if it were an ingot of U235, that would be a much different proposition. In fact U238 that is used for nuclear reactions are artificially enriched to have a greater amount of U235 than the 0.7% of natural U238. A pure ingot of U238, that is devoid of U235 is safe because of the lack of U235.

Not totally correct, while it might be slightly Radioactive instead of blistering hot with the larger %age of U235, it is still HIGHLY toxic in small amounts.
Uranium compounds especially Uranyl Nitrate cause acute renal failure and brain damage. As a pure metal is it is also teratogenic and it's compounds are even more so.

Have had some experience with Uranyl Nitrate and Peroxide, they are to be give great respect. Uranyl Nitrate used to be used as a Photographic toner up until the early 80's.
Many old schools have large regent bottles from Kodak that still contain copious amounts of the material.

 

[Sigurthr]

Well yeah, lol. I wouldn't go licking it, haha.

Definitely spot on with the salts though. There's a reason I wanted a nondispersable ingot and not the nitrate or oxide which is easy to come by.

 

[paul1598419]

I was talking about uranium that has been depleted and is often used for military bullets. It is true that even depleted uranium has some radioactive emissions, it is not nearly as toxic as natural uranium.


Edit: the salts of uranium, especially hexavalent uranium are toxic for chemical reasons more than for radioactive ones. Though less toxic than mercury or other heavy metals, uranium salts are chemically toxic and are far more dangerous than depleted metallic uranium.

 

[Seoul_lasers]

I was talking about uranium that has been depleted and is often used for military bullets. It is true that even depleted uranium has some radioactive emissions, it is not nearly as toxic as natural uranium.


Edit: the salts of uranium, especially hexavalent uranium are toxic for chemical reasons more than for radioactive ones. Though less toxic than mercury or other heavy metals, uranium salts are chemically toxic and are far more dangerous than depleted metallic uranium.

Actually have had experience with Hazmat, I'd say Uranium compounds are equally or perhaps more toxic than Hg ones but perhaps not quite as dangerous as Thallium salts. Thallium is an incredible poison.
Uranyl Nitrate is a potent renal function killer. It works nearly instantly. fortunately, thank goodness I have never had the opportunity to experience this.

Natural Uranium is 99%-99.8% U238 and about ~1.0-0.2% U235. it doesn't matter if it is enriched Uranium or depleted Uranium.
Both are toxicologically equal. They are of course fundamentally different animals radiologically.

All heavy metal (Hg, Pb, Cd, U, Cr, Tl) compounds that are hexavalent are highly biologically active. The reason why this is so is quite complicated. Basically the cells in a human body allow more easily (IV)
form molecules to pass through the cell wall where they can damage DNA and wreak all sorts of havoc.
The damage done to the DNA is potentially hereditary, or Teratogenic meaning that damaged DNA can pass from Adult to Fetus. (causing congenital abnormalities)

I hope puts to rest the myth of natural uranium vs processed uranium = lower toxicity.

 

[Sigurthr]

Aye S_L, in the first part of his post I thought he wrote toxic instead of radioactive since the second half counters the first half.

Yeah... Thallium... that's an element I won't go near. Not even for scint probes, no thank you. Like many I used to "play" with various heavy metals as a kid. Pb, Cd, Cr, Hg, V, Bi (not really toxic), Co, Mn, etc. I had a lot of fun making Wood's Metal and making spoons and forks out of it, hehe. Turned out fine (toxicologically anyway =P ) but these days there's little reason to risk things with toxic substances.

 

[paul1598419]

Uranyl nitrate is a hexavalent(VI) compound and is very toxic. I am quite aware of it's toxicity to the kidneys. I thought that was the point of my post. That it is toxic as a heavy metal salt and not because of its radioactivity. My other point, was that these salts are more toxic than the metal ingot. I wouldn't go near thallium either, but depending on the uranium salt, some authorities may differ on which is more toxic... Hg or U.
BTW. who put forth the idea that processed U was less toxic than natural U? I said that depleted metal U was less radioactive than natural U, but that is not the same thing. I guess you took the sentence where I said radioactive and toxic interchangeably as meaning more than just radioactively toxic.

 

[Seoul_lasers]

Aye S_L, in the first part of his post I thought he wrote toxic instead of radioactive since the second half counters the first half.

Yeah... Thallium... that's an element I won't go near. Not even for scint probes, no thank you. Like many I used to "play" with various heavy metals as a kid. Pb, Cd, Cr, Hg, V, Bi (not really toxic), Co, Mn, etc. I had a lot of fun making Wood's Metal and making spoons and forks out of it, hehe. Turned out fine (toxicologically anyway =P ) but these days there's little reason to risk things with toxic substances.

Yes, woods metal is a lot of fun. I also used to play with liquid Hg as a kid. I have been tested 5x for exposure for various govt agencies, here in Canada and abroad in S.Korea. No amount made it into my blood. I would never advocate playing with it like I did..akin to playing russian roulette.

Cd as I have found out as a metal is pretty ok to work with... better than Pb, but it's compounds are fairly bioaccumulative. We used 70Cd:30 In for low temp electronic soldering for my pervious electronics course. Very special stuff, it's available in sheets rather than spool.

 

[paul1598419]

Have neither of you heard of radiation poisoning or radiation toxicity? The terms are not mutually exclusive. I thought I was careful to mention chemical toxicity as apposed to radioactive toxicity. Look them up in whatever authority you like.

 

[Seoul_lasers]

Have neither of you heard of radiation poisoning or radiation toxicity? The terms are not mutually exclusive. I thought I was careful to mention chemical toxicity as apposed to radioactive toxicity. Look them up in whatever authority you like.

Sorry, I am not nitpicking here, I hear quite a bit of jargon being used improperly and we've got to be careful what terms we're referring to.

again, back to the terms ... they're not used like that in the field. The terms were talking about here are completely exclusive of each other. A Radioactive material can be toxic chemically and fairly benign radiologically. Just as a the reverse is true. Radiation toxicity why did I jump on this term? It infers Radiation is a physical toxin than an energy based exposure like eg. X-rays.

I just completed my CRNC certification for soil moisture density meters a few weeks ago with my new course.
One of the parts of the license is the technical jargon used to explain incidents related to Radioactive isotopes.

 

[Sigurthr]

Ahh I gotcha now Paul. I had a feeling you weren't wrong in what you were saying but you were saying it incorrectly, thus giving the wrong impression. No worries.

As with S_L I've never heard of that term (radiation toxicity) being used in the field (I don't have as much official experience as S_L but I did rad first-responder and some basic rad tech's rad safety courses). Even the term radiation poisoning is frowned upon; the term radiation sickness is what's used.

 

[paul1598419]

I can see where you are coming from. I'm an older guy and I grew up with the term radiation poisoning. Just to be sure, I checked several sites to see if I was mistaken, but it was there still. I will just bow to your newer license certification and say I was wrong in my phrasing. I wasn't, however, trying to say that there isn't such a thing as U heavy metal poisoning. My understanding is that it is the hexavalent salts that are the toxic ones and the other salts are not nearly as toxic as Hg, Cd or other heavy metal salts. That was really the only point I was trying to make. Now, it is true also that metal dust that is inhaled or aspirated of U that can also cause cancer and other types of radiation sickness. But, depleted U in a form that doesn't give rise to particulate matter is relatively safe from a radiation sickness causing form if not exposed constantly.