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Depleted Uranium Radiation   , or else known as "depleted uranium", decays to and emits an α particle of energy 4274keV(79%) or an α particle of energy 4151keV(20,9%) and a γ photon of energy 49,55keV as the decay diagram shows. The disintegration constant is . If we consider a litre of (which is produced by the impact of a bullet*) then the number of uranium atoms is . The activity of the source is . The flux rate of the radiation at the distance of one meter will be and at the distance of one centimeter will be . The exposure rate at the air is given by the expression in units of were the activity is mesured in mCi, the distance in cm and the energy in MeV. In our case we have , , and so the exposure rate at the distance of one centimeter will be and at the distance of one meter will be . The dose rate is given by the expression and if the exposure rate is in units of then the dose rate is in units of . In our case we will have: distance 1cm time dose 24h 1,43mrad 30d 43mrad 1y 524mrad   The equivalent dose is given by the expression were Q is the quality factor of the radiation, and if the dose is in units of rad then the equivalent dose is in units of rem. radiation Q α 10 γ 1   In our case we will have: distance time DE 1cm 24h 1,43mrem 30d 43mrem 1mm** 1h 5,98mrem 24h 143,69mrem 30d 4,31rem 1y 52,45rem   Permitted limits Professionals General population blood producing organs, bone marrow 5rems/y 0,5rems/y bones, skin 30rems/y 3rems/y limbs 60rems/y 6rems/y other organs 15rems/y 1,5rems/y   If the one litre we have considered is placed inside a lung and to all that is added the dose due to the α radiation and the dose of the environment then things are becoming very worrying.     The above calculations are telling us: A 30mm bullet of depleted uranium stored in an ammunition warehouse doesn't emit significant radiation and it can bee shielded without grate danger. When a bullet hits the armor of a tank, one part of it burns to produce uranium dioxide and the rest of it remains in the air as dust particles. The dust particles are the most dangerous because they are higher concentrations of uranium. If one inhales these particles or the uranium dioxide, the quantity that will be absorbed by the organism will produce a significant radiation dose which can be dangerous since the exposure will be for a long period of time an the source of radiation will be very close to the tissue. If we try to detect the radiation that these particles add to the environment we will probably fail due to the low concentration of these particles. So such measurements should not be reassuring. Finally what needs to be pointed out is that the problem is created by the accumulation of a significant quantity of uranium in the human organism. Because the organism doesn't reject these substances, they accumulate to high concentrations. So it is not necessary the introduction of the uranium to the organism to happen at once. We can have continuous introduction from the water, the air and the food from the area of the bombing.    * Every 30mm bullet that was fired by the Α-10 aircrafts has 299gr of depleted uranium that is capable of producing at list 1 litre of uranium dioxide(actually it is capable of producing about 20 litres). ** I am interested in that size scale because inside the organism these are the mean distances of the particles from the tissue.   Here are some links on the subject of depleted uranium: Extreme deformities in Iraqi children Gulf War Syndrome Message Board Where and how much depleted uranium has been fired? DEPLETED URANIUM WEB ARCHIVE PGU-14/B API Armor Piercing Incendiary [DU] 30mm Ammunition for the A-10 aircraft M829 120mm, APFSDS-T(Armor Piercing, Fin Stabilized, Discarding Sabot-Tracer) And something on nuclear physics: Glossary of Nuclear Terms

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