FAQ - Uranium Daughters/radon etc. Oh my...another diatribe!

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Richard Hull
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FAQ - Uranium Daughters/radon etc. Oh my...another diatribe!

Post by Richard Hull » Tue Oct 22, 2019 9:03 pm

This post will be a long one, but if you hang in there and read it all, you will be the wiser and informed on these issues. For those not wishing to read the entire post, I include a brief over view of just the facts prior to the reasoning and the teaching part of the post. This first part will conclude with an underscore of long asterisks. Those who know it all are excused from class at that point.

The following Uranium items will contain no late blooming, dangerous and highly radioactive daughters of Uranium. Thus, you will never encounter contained radium, radon emission, radio-bismuth, radio-lead, radio-polonium, radio-thallium in.............

1. Uranium chemicals
2. Uranium colorant contained in pottery or glass ware (Green or yellow U glass or Fiesta ware, etc.)
3. Uranium Metal or any alloys containing Uranium
4. Uranium being placed in a nuclear reactor.

None of the above need to have any extremely special handling in most any quantity by the experimenter beyond the normal gloved, limited handling and storage only a few feet from constant human activity.


The only place on the planet where you will find any of the nasty Uranium daughters in full bloom is in NORM. Naturally Occurring Radioactive Materials of geologic age. This includes uranium found in soil, sand, and Uranium ore (rock). Radium found in old manufactured goods is particularly dangerous and deserves ultra special precautions. (not discussed here)

These are real facts and below we will explain the full story of why the above are, indeed, facts.

**********************************************************************************************************************************************************************************************************************************************************
Purified Uranium and its radiations

Fact: All Uranium atoms on this planet are much older than 5 billion years.

All uranium , like gold silver and copper is a mined product. Unlike gold, silver and copper, Uranium, due to its many oxidation states, is never found native in its relatively pure metallic state. As such, uranium must be chemically treated and separated from its ore before it can be used by man for any purpose.

We will deal solely with the four initial forms listed above and not the ore in this first section. 100% of all uranium chemical separations never yield the metal. Instead, a uranic chemical is always the result of the first step from ore to pure uranium metal. In the case of uranium chemicals there is always pure uranium in the chemical. uranium oxide U3O8 contains three atoms of pure Uranium and eight atoms of oxygen.

Pure uranium has three natural isotopes. They are all radioactive and all three are alpha particle emitters when they decay. Thus, in all pure uranium chemicals or metals, at the time of purification the three isotopes are present with the following abundances in mass and half lives.

1. U238 Virtually 50% 4.51 billion years
2. U234 Virtually 50% 233,000 years This isotope is a daughter product of U238 and was in full equilibrium with all uranium originally produced in an ancient super nova or exploding or colliding neutron stars within 1.5 million years as it drifted through space, long before it became part of the solar nebula from which the Earth and Sun formed ~4.5 billion years ago.
3. U235 0.7% 707 million years

As all are alpha emitters, purified uranium will not be detected as radioactive with most standard GM counters! Only mica windowed counter detectors will detect freshly purified uranium chemicals. However, these are radioactive, too, and immediately start to decay to their, specific, next daughter product. So, new radioactive daughter products grow in over time. We will look at the "early" daughter products. These are the first short lived daughters, where there are any, that will join in full equilibrium and increase the radiation "activity" from a uranium chemical or metal over time. By early daughters, we mean daughter products that will show up in full equilibrium within a century after the uranium chemical is purified.

U238 This is the "big boy" Within less than a half year our purified U chemical or metal will have its full daughter compliment of Thorium 234 which is a potent beta emitter added to the three alphas. However within one more day we have the full equilibrium compliment of protactinium 234 grow in from the thorium 234 already in equilibrium. Pa234 is an even more potent beta emitter and any GM counter on earth will read the chemical as being very hot indeed even though it may miss the still steaming hot 3 alphas from the original purified uranium isotopes. Pa 234 decays to U234 which, as noted above, is a daughter product which when purified was already in equilibrium and Pa 234 will keep it there. (It normally takes about 5 half lives for a daughter to "grow into full equilibrium.) Fast daughters actually grow in co-jointly over time. Obviously, one daughter does not need to be in equilibrium before the next daughter can start.

U234 Here we will not see much added for as it decays, U234 will need 1.25 million years from purification via its alpha emission to come into full equilibrium with its daughter thorium 230. Thus, on a century time scale we will not see any real amount of Th230 grow into our purified U chemical or metal.

U235 There is so little U235 in purified Uranium that its alpha radiation is nearly zip. Even being zip, U235 does have one fast beta emitting daughter in full equilibrium only 5 days after purification! This daughter is Thorium 231. As there is very little U235 in purified U there will also very little Th231 to make a significant radiation signature of beta emission. Th231 will need 125,000 years to generate protactinium 231 in equilibrium, so there is effectively zero Pa231 in purified uranium over a century time scale.

It is important to glean that other than three alpha rays and two beta rays at maximum emission within 1.5 years after uranium is purified to chemical or metal, this is all the charged particle radiations you are going to get from purified uranium on a single century time scale. No radium and no radon ever. The old hot uranium colorant fiesta-ware is all beta emission from Thorium 234 and Protactinium 234....Not the uranium!! The bulk of the true alpha emission is stopped dead by the rather thick glaze applied over the colorant to keep its color brilliant and to avoid the color wearing off.

Again, zero nasty daughters like radium or radon in any uranium chemical or metal product. When the ore was processed to yield only the uranium chemical, all other chemical elements friendly or lethal left and were thrown out in the highly radioactive and toxic bath water.

How long before fiesta-ware will be nasty to health due to radium content and radon emission? It will be about 400,000 years before fiesta-ware made from the 1930s through the 1950's will be a true hazard.



Uranium Ore - natural uranium of geologic age

Fact: All Uranium containing ore and rock contains Uranium in the form of a chemical

The oldest untouched uranium ore rock has had more than enough time to have all of its daughters in full equilibrium. This includes the very late super fast and intensely radioactive daughters of much greater activity than the uranium element itself. Madame Curie discovered Radium and Polonium strictly on the basis that ore was intensely more radioactive than purified uranium.

Here is a general list of all the long period "grow-in" daughters that are realized in purified uranium and in full equilibrium once 500,000 years have passed and their half life beyond the early daughters listed above for purified Uranium.

Thorium 230 83,000 years would reach full equilibrium in about 500, 000 years.
Radium 226 1600 years would take about 9000 years to reach full equilibrium
Radon 222 3.8 days would take 25 days to reach full equilibrium
Polonium 218 3 minutes equilibrium attained in 20 minutes
Lead 214 27 minutes equilibrium in 2 hours
Bismuth 214 20 minutes equilibrium in 1.5 hours
Polonium 214 .00015 seconds equilibrium instantly
Lead 210 22 years equilibrium in 100 years
Bismuth 210 5 days equilibrium in 1 month
Polonium 210 140 days equilibrium in 2.5 years
Lead 206 stable end of the Uranium decay chain

You can see that after about 510,000 years, The purified U238 and U234 have decayed enough to contain full equilibrium or maximum output radiation from all of the foregoing radioactive daughters.
U235 has such a small mass component of natural uranium that it reaches equilibrium in about 200,000 years. This is much faster that the massive content of its fellow isotopes. The total sum of U235 full equilibrium daughters radiation added to the others is rather minuscule.

Again, we are dealing with uranium chemicals usually in the form of the oxides, although often united with other metals in the form of cuprates, vanadates, etc. Uranium is a very gregarious chemical element. Uranium can weather in or out of various chemical states over the eons of time due to volcanic eruptions, rain tainted with acids or other caustic chemicals. In doing this, it is often rid of its geologically aged daughters into another chemical form. As such, especially in surface uranium deposits, the uranium may have weathered and the requisite 500,000 years has not passed to accumulate a full load of daughter products. Such uranium ore will be a bit less radioactive than that found at great depths mined from the earth. Now this surface ore is still full of all the uranium we seek when reducing to just obtain uranium. After all, uranium with or without any daughters is still uranium.

Radiations from Uranium ore

Uranium ore is one of the most radioactive sources you might obtain other than reactor bred isotopes. Tremendous alpha, beta and gamma radiation pours off ore as all of the daughters possible are there and just itchin' to decay. Some daughters are so fast near the end of the decay chain that they are blasting out huge activity levels for their mass compared to the mass of uranium in the ore. The saving grace is that all alpha radiation and most all of the beta radiation is from purely surface or visible streaks of uranium. All of the internal alpha and beta emissions never break the surface. They are all absorbed within the huge volume of the stone. Gammas are different. Gammas range from 60kev (x-ray level energies) which are mostly absorbed like the alpha and beta radiations, all the way up to nearly 2 mev which needs many feet of shielding to effectively reduce to near background level. a GM counter will never read much gamma radiation as all are very poor detectors for the non-charged, penetrating gammas. So, for a really hot ore specimen as read by a GM counter you are mostly reading beta radiation at a range of a couple of inches. A mica windowed GM detector can almost double the counts on a GM meter if held very near the surface to a big group of visible streaks or patch of surface uranium oxide. Really hot ore is very desirable to have when setting up a neutron counter to set the windowing and eliminate all gamma detection from being counted.


Uranium ore safety tips

Good Uranium ore in rock form is therefore probably in full equilibrium in most cases and has the maximum amount of radium and radon emission possible based on the uranium content. As such, handling and storing of the ore is bit more of an issue than with uranium chemicals or Uranium metal. All ore should be kept, ideally either outside in a naked rock pile 50 or more feet from a dwelling or work place. If kept in an outside shed or garage that is used often, It is best to place it in a sealed container, preferably with a gasket seal. Steel Military ammunition canisters are ideal and readily found at surplus stores and flea markets. They are steel and will stop all alpha and beta radiation and are all gasket sealed with a very tight latching system. All such containers should be opened only out of doors to allow the Radon drift out if you wish to see or use the contents. Gloves are especially needed to be worn when removing a just opened box of ore as the bags and the box itself are in full equilibrium with all the 7 lower fast and very hot daughters in the listing above in this section on ore. Be very careful when messing with sealed storage containers that have just been opened. Give them a few hours to out gas and ditch the bulk of their later, fast burner intense isotopes.


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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Richard Hull
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Re: FAQ - Uranium Daughters/radon etc. Oh my...another diatribe!

Post by Richard Hull » Wed Oct 23, 2019 7:19 am

Finally, all done with the above post

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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