Depleted Uranium Again

[aerocontrols]

Believe me, at the muzzle-speed of these weapons, the ground IS really really hard.

Hans

I'm sorry but I don't believe you.

 

[kookbreaker]

Aero, good point about armor being useless once it to too heavy to use.

The best example of this is the fact that full suits of plate armor went out of use as soon as guns became strong enough to make the suits have to be too thick and heavy to be worth wearing.

Armor was indeed made well into the 15th century that could still stop rifled rounds (the best at that time, though rare). The problem was, the armor weighed over 200 pounds, making the wearing totally immobile in battle. It became totally impractical to wear it, and people started to realize that since you weren't gonna stop those bullets, mobility and ease of movement (ie: run and hide) woudl make far more sense.

Within 40-50 years, Europe went from being incased in full plate to NO armor whatsoever. And the British started wearing Bulls-Eyes for uniforms, lol!

Course, when the Spanish came to the maerica's armor proved useful again, because their enemy had no guns, and only very simple bows, arrows, spears, and clubs. A helmet and breastplate work VERY well against that kind of stuff.

Not to nit-pick, but it wasn't so much the weight of the armor as it was the expense. The cost became prohibitive to equip fully armorered knights when 20 angry peasants with pikes (or muskets) could do the job at less cost.

Some cavalry units actually kept their armor right up to WW1, it did have some function in melee situations.

 

[LW]

Armor was indeed made well into the 15th century that could still stop rifled rounds (the best at that time, though rare).

Make that 17th century. Nobles participating in the 30 year war still wore full or half plate suits. Mercenaries and other common soldiers didn't since they were very expensive.

Full plate suits didn't appear before 15th century. The 17th century cuirasses could stop a close-fired pistol round or a long-distance musket shot.

The problem was, the armor weighed over 200 pounds, making the wearing totally immobile in battle.

No, it didn't. A combat full plate suit weights around 60-70 pounds, about as much as infantryman's package in WWI. Its main usability drawback was not the weight but heat.

Tournament armor is a different question. It was much heavier and the helms were often
bolted in place so the wearer could look only forwards. Some tournament cuirasses had three iron plates on top of each other, combat armor was never as heavy.

 

[DrMatt]

Re: New questions that may interest:

[*]How toxic is the area around the tank?
[*]How toxic will the area around the tank be in 2 years?
[*]How much does this toxicity change if the tank is destroyed with DU rounds rather than lead or tungsten rounds?
[*]How much is changed about the toxicity of the area around the tank after 2 years if a lead or tungsten shell is used?

and why is this knight different from all other knights?

 

[DrMatt]

No, it didn't. A combat full plate suit weights around 60-70 pounds, about as much as infantryman's package in WWI. Its main usability drawback was not the weight but heat.

And then there was chain mail, which evolved into spam.

 

[kookbreaker]

No, it didn't. A combat full plate suit weights around 60-70 pounds, about as much as infantryman's package in WWI. Its main usability drawback was not the weight but heat.
.

It was actually better distributed, weight wise, than the infantryman's pack.

 

[aerocontrols]

No, it didn't. A combat full plate suit weights around 60-70 pounds, about as much as infantryman's package in WWI. Its main usability drawback was not the weight but heat.

It was actually better distributed, weight wise, than the infantryman's pack.

It seems to me that we should be comparing the weight of an infantryman's armor (helmet + flak jacket) to this alternative armor, rather than the weight of his entire pack.

Doesn't it seem that way to you guys? Wearing plate armor will not alleviate an infantryman of the rest of his pack.

MattJ

 

[davefoc]

What does AUP have to say about all this? Does he agree that Rokke is not credible? So far in this thread and the other threads referenced nobody has stepped forward to defend Rokke's view.

 

[LW]

Wearing plate armor will not alleviate an infantryman of the rest of his pack.

Yup, but no infantryman wore a full plate armor. Plate armor was for cavalry and they used pack horses to carry their other stuff.

I brought forward the comparison between a knight and a WWI infantrymen because the belief that a knight was so heavily loaded by his armor that he couldn't function at all is still quite common.

 

[TillEulenspiegel]

All DU shells are is denser and heavier. there is NO nuclear ability in them, no radiation (hence the DEPLETED part of the name).

Not quite accurate as the shells are an alpha emitter ( which can be blocked by a sheet of paper. The main concern however is that the shells contain contamination ( in extremely small quantities) of americium and plutonium. Such amounts would be of no consequence if the thing is carried aground , but become a problem when the material vaporizes at point of contact with DE armor, reactive armor and yes even dirt. It is then a particulate that can be inhaled , absorbed , even deposited as dust.

 

[davefoc]

TillEulenspiegel,
Thank you for your post. Could you provide some quantitative context?

How likely are these radioactive materials to be a problem? What are the problems with cleaning up an area that has been exposed to a spent DU shell? How does the radiation levels inside a tank that has been destroyed with a DU shell compare with the radiation levels inside a tank that has been destroyed with a lead shell?

Presumably there are some radioactive materials present at trace levels in all metals. Are the trace radiactive materials in DU shells significantly higher than the trace radioactive materials in lead shells?

 

[Jon_in_london]

From the link I posted above:

The Royal Society reports on "The Health Hazards of Depleted Uranium Munitions", state that "except in extreme circumstances any extra risks of developing fatal cancers as a result of radiation from internal exposure to DU arising from battlefield conditions are likely to be undetectable above the general risk of dying from cancer over a normal lifetime".

DU particulate remains highly localised to the points of impact where DU munitions have struck hard targets: only in these small areas would DU levels be significant enough to necessitate precautions to prevent or reduce possible intakes. Increasing amounts of independent research by eminent scientists within groups such as the Royal Society DU Working Group and the United Nations Environment Programme support this view.

With regard to civilians, the Royal Society states that “For those returning to live in areas where DU munitions were deployed, including peace-keepers, the inhalation intakes from resuspended DU are considered to be unlikely to cause any substantial increase in lung cancer or any other cancers”. The claim, that DU is the cause of an excessive rise in cancers and birth defects amongst children in Iraq, is not substantiated with credible scientific evidence.

Furthermore:

The recent EC report of experts has concluded that, with regard to radiological health consequences, "exposure to DU could not produce any detectable health effects under realistic assumptions of the doses that might be received."(1). On 12 March 2001, the WHO published its report of its Mission to Kosovo (112) and commented that there is no convincing evidence "to indicate any health impacts to the Kosovo population associated with the use of DU."

 

[John Harrison]

TillEulenspiegel,
Thank you for your post. Could you provide some quantitative context?

How likely are these radioactive materials to be a problem? What are the problems with cleaning up an area that has been exposed to a spent DU shell? How does the radiation levels inside a tank that has been destroyed with a DU shell compare with the radiation levels inside a tank that has been destroyed with a lead shell?

Presumably there are some radioactive materials present at trace levels in all metals. Are the trace radiactive materials in DU shells significantly higher than the trace radioactive materials in lead shells?

This may help:

The toxic and radioactive particulate material produced by the DU combustion process can be divided into two broad categories

i) First, material initially within the plume which would be too heavy to remain there for a prolonged period and would, therefore, deposit on the ground within a few tens of metres of the point of impact. This material would take a considerable amount of time to dilute and disperse, but would be relatively easy to detect.

ii) Secondly, other lighter material, some of which would be respirable. Based on hazard assessments and data obtained during the test-firing of UK DU-based ammunition, the Defence Evaluation and Research Agency’s Radiation Protection Service (DRPS) assesses that such material within a plume would be fairly rapidly diluted and dispersed into the environment by the weather, to the point where it would usually become difficult to detect further than about one hundred metres away from the point of impact, even with the most sophisticated radiation monitoring equipment.

9. On the basis of the above, it is unlikely that anyone other than those in an armoured vehicle penetrated by a DU projectile, or those spending prolonged periods within a few tens of metres of the point at which a DU penetrator had impacted with a hard target, would be exposed to large enough quantities of particulate material for them to receive a radiation dose greater than 20-30 millisieverts. For comparison purposes only, the statutory UK annual whole body dose limit for employees, aged 18 years or over is 50 millisieverts.

10. It is theoretically possible that some DU dust may have been inhaled or ingested by those who came into contact with individuals who had DU contamination on their outer clothing or skin as a result of being in, or close to, tanks during, or shortly after, they were penetrated by DU penetrators (ie. Iraqi prisoners-of-war and both Iraqi and Coalition casualties). However, the DRPS advises that this does not represent a credible route of exposure because the level of risk reduces as the amount of DU available to be taken into the body decreases, and the amount of DU contamination on an individual’s clothing would be very much less than that in or around vehicles penetrated by DU penetrator cores. The level of risk also reduces as the time since the incident, which led to the contamination, increases. This is because any contamination on a prisoner’s or casualty’s clothing (and particularly the respirable material which is of most significance to health) will either be removed by the effects of the weather and body movement or will become ingrained in the fabric. Consideration of the amount of time spent in close proximity to contaminated casualties (ie. within 1 to 2 feet) and the type of dust-raising operations that might occur also mitigate against this being a significant route for DU intakes. It is for these reasons that organisations such as the US National Council on Radiation Protection and Measurements have stated that there are only rare instances when those handling contaminated individuals require any form of respiratory protection.

-snip-

What are the possible health-effects of the exposure scenarios described above?

13. A potential health hazard from DU is posed by its level of chemical toxicity, which is similar to that of other heavy metals, such as lead. This could give rise to health problems if soluble DU were to be ingested or inhaled (see paragraphs 15 to 17 below), but this is very unlikely as the DU residues found on the battlefield are generally in the form of solid DU fragments or relatively insoluble particles. Should any of these insoluble particles be ingested, most would pass straight through the body and the risk of any health effects arising from this exposure route would therefore be negligible. The inhalation of insoluble particles gives rise to possible health-effects resulting from the radioactive rather than toxic properties of DU. This is because insoluble particles are generally retained in the lung for prolonged periods and are excreted very slowly and at concentrations unlikely to affect the kidney, which is the organ at most risk from any toxic effects.

14. Exposure to alpha and beta radiation from inhaled insoluble DU particles could, theoretically, lead to damage to lung tissue and subsequently to a raised probability of lung cancer some years later. For the exposure conditions possibly encountered by UK troops during the Gulf conflict, hazard assessments carried out by DRPS in 1993 indicate that the worst case DU exposures would result from the inhalation of several milligrams of DU per hour. A continued exposure at this level over a period of a few tens of hours could lead to the statutory UK annual whole body dose limit for employees aged 18 years or over (50 millisieverts) being exceeded. No observable medical effects would occur, but the individuals would be at a slightly increased risk of developing cancer in later life. However, this level of exposure would only occur if personnel were involved in dust-raising operations inside tanks that had been penetrated by DU penetrators.

 

[Beausoleil]

Not quite accurate as the shells are an alpha emitter ( which can be blocked by a sheet of paper. The main concern however is that the shells contain contamination ( in extremely small quantities) of americium and plutonium. Such amounts would be of no consequence if the thing is carried aground , but become a problem when the material vaporizes at point of contact with DE armor, reactive armor and yes even dirt. It is then a particulate that can be inhaled , absorbed , even deposited as dust.

Depleted uranium shells are primarily a beta emitter - the first two steps on the decay series get to equilibrium within one year of production, and are both beta emitters. Since beta is more penetrative, a greater depth of the shell contributes to the flux at the surface. Beta activity at the surface is about 20x alpha activity if I recollect.

In spite of propoganda, depleted uranium rounds were not particularly effective in destroying armour in the gulf war. Most Iraqi tanks were destroyed by other means.

(I researched this for a debate on a different site some time back, can probably dig up the reference if necessary.)

 

[John Harrison]

Depleted uranium shells are primarily a beta emitter - the first two steps on the decay series get to equilibrium within one year of production, and are both beta emitters. Since beta is more penetrative, a greater depth of the shell contributes to the flux at the surface. Beta activity at the surface is about 20x alpha activity if I recollect.

In spite of propoganda, depleted uranium rounds were not particularly effective in destroying armour in the gulf war. Most Iraqi tanks were destroyed by other means.

(I researched this for a debate on a different site some time back, can probably dig up the reference if necessary.)

I would be interested in seeing the reference, since all the information I have found states that DU is primarily an alpha emitter.

 

[aerocontrols]

I would be interested in seeing the reference, since all the information I have found states that DU is primarily an alpha emitter.

Me, too. Could the confusion be linked to 'how many particles' vs. 'how much energy' is emitted?

MattJ

 

[Ziggurat]

Uranium decay

http://ie.lbl.gov/education/parent/U_iso.htm

Here's the decay facts for various isotopes:
(1 My = 10^6 years)

isotope halflife principle decay
U233 0.16 My alpha
U234 0.24 My alpha
U235 stable -
U236 23.4 My alpha
U237 6.8 days -beta
U238 stable -
U239 24 min -beta

DU is of course mostly U238, don't know how exactly much of the other isotopes. But the only beta emiters have such short half-lives that they can't be a significant part of depleted OR enriched uranium. There are a more isotopes with very short halflives (< 1 hour) that I didn't list but that doesn't matter for DU.

Furthermore...

U233 decays to Th229, which is ALSO an alpha emitter.

U234 decays to Th 230, also an alpha emitter

U236 decays to Th 232, which is stable.

 

[davefoc]

So far in this thread and in both the others nobody stepped forward to defend Rokke's view very strongly if at all.

It looks like only AUP is left to defend the Rokke view and argue that America once again is up to its old evil empire tricks. But where is AUP? Is it possible that not even he can figure out how America is guilty on this issue. Maybe, the evil empire is innocent this time or maybe AUP is just mellowing.

 

[kookbreaker]

So far in this thread and in both the others nobody stepped forward to defend Rokke's view very strongly if at all.

It looks like only AUP is left to defend the Rokke view and argue that America once again is up to its old evil empire tricks. But where is AUP? Is it possible that not even he can figure out how America is guilty on this issue. Maybe, the evil empire is innocent this time or maybe AUP is just mellowing.

I can remember a few years back a couple of Italian soldiers stationed in the Balkans were diagnosed with Leukemia. The European press immediately started to blame the US DU shells, despite the fact that very few such shells were used. I beleive Mr. Rokke was fanning the flames there too.

The reality set in that:

1) Leukemia could not have developed in the time between the soldier's exposure and the diagnosis.

2) The soldiers lived in an industrial town with, shall we say, Old Evil Empire pollution standards.

Pheh.

 

[kookbreaker]

It seems to me that we should be comparing the weight of an infantryman's armor (helmet + flak jacket) to this alternative armor, rather than the weight of his entire pack.

Doesn't it seem that way to you guys? Wearing plate armor will not alleviate an infantryman of the rest of his pack.

MattJ

Not really, a pack for a medieval soldier would not consists of more than his armor, weapon, maybe a tool of some kind and personal items in some container. Soldier's didn't fight far from the wagons, so they didn't need to carry food, only archers required arrows.

Compared to the modern soldier who must carry his weapon, many clips of ammo, armor, grenades, canteen, food, personal items, specialty weapons (LAW, mortar parts, etc.), plus a possible host of other potential items like radios, stretchers, sidearm, tent, medical kit, sleeping bag, night vision gear, etc. etc.

Obviously, WW1 soldiers didn't carry that much, but they still had a packload to carry.