Radioactive cloud effects

Potassium iodide, also called KI, only protects a person s thyroid gland from exposure to radioactive iodine. KI will not protect a person from other radioactive materials or protect other parts of the body from exposure to radiation. It must be taken prior to exposure (for example, if people hear that a radioactive cloud is coming their way) or immediately after exposure to be effective. Since there is no way to know at the time of an incident whether radioactive iodine was used in the explosive device, taking KI would probably not be beneficial.Also, KI can be dangerous to some people. Taking KI is not recommended unless there is a risk of exposure to radioactive iodine. 

The Food and Drug Administration (FDA) recommends that KI be taken as soon as the radioactive cloud containing iodine from the explosion is close by. KI may still have some protective effect even if it is taken 3 to 4 hours after exposure to radioactive iodine. Because the radioactive iodine will be present in the initial blast and decays quickly, a single dose of KI may be all that is required. The FDA recommendations on KI can be reviewed on the Web at http //www.fda.gov/cder/guidance/4825fnl.htm. 

This method does not take into account the shielding effect of the ground roughness, nor the dimensions of the initial radioactive cloud. These effects, given the largely indicative character of these estimates, are to be considered as secondary. 

Rain or snow are much more important than these effects on the distribution of the contamination by causing a washout of the radioactive cloud and a patchy distribution of the unit dose. 

Aerosols Cloud Physics Environmental Radioactivity Greenhouse Effect and Cumate Data Greenhouse Warming Research Imaging Through the Atmosphere Ozone Measurement and Trends (Troposphere) Radiation Sources Solar Thermal Power Stations... 

An underground nuclear detonation would have the advantage that if fired at the appropriate depth it would be completely contained. There would be no radioactivity entered to the atmosphere and thus no problem arising from the movement of a radioactive cloud or the fallout therefrom. The firing of an underground shot would therefore be independent of weather conditions. It would also have the advantage that there would be no offsite effects such as noise, flash or shock. .. 

Ionization and condensation nuclei detectors alarm at the presence of invisible combustion products. Most industrial ionization smoke detectors are of the dual chamber type. One chamber is a sample chamber the other is a reference chamber. Combustion products enter an outer chamber of an ionization detector and disturb the balance between the ionization chambers and trigger a highly sensitive cold cathode tube that causes the alarm. The ionization of the air in the chambers is caused by a radioactive source. Smoke particles impede the ionization process and trigger the alarm. Condensation nuclei detectors operate on the cloud chamber principle, which allows invisible particles to be detected by optical techniques. They are most effective on Class A fires (ordinary combustibles) and Class C fires (electrical). 

The temperature at the aerosol layer in Neptune s atmosphere is about -346°F (-210°C), which is close to the temperature at the main cloud level in Uranus s atmosphere, and the effective temperatures of the atmospheres of both Uranus and Neptune were found to be close to this temperature. One would expect Neptune s visible troposphere and lower stratosphere to be about 59°F (15°C) colder than those of Uranus because of Neptune s greater distance form the Sun (30.1 a.u. vs. 19.2 a.u.) instead, the temperatures of these parts of the atmospheres of both planets are found to be about the same. Neptune s atmosphere seems to be considerably warmer than it would be if it received all or nearly all its heating from sunlight, as seems to be the case for Uranus. This is another indication that Neptune has a powerful internal heat source, unlike Uranus, which has at most a weak internal heat source (compatible with radioactivity in its interior) or none at all. Voyager 2 infrared observations confirmed this the emission to insolation ratio was found to be 2.6 from them instead of... 

If the accidental release of radioactivity were to occur from the top of a high stack, the cloud-dosage at ground level immediately downwind of the reactor would be much smaller than indicated by either Fig. 1 or Fig. 2. The method recommended by Pasquill to represent this effect is to multiply the expression (7) by a factor F where... 

As the fireball rose into the air, Joseph W. Kennedy reports, the overcast of strato-cumulus clouds directly overhead [became] pink on the underside and well illuminated, as at a sunrise. Weisskopf noticed that the path of the shock wave through the clouds was plainly visible as an expanding circle all over the sky where it was covered by clouds. When the red glow faded out, writes Edwin McMillan, a most remarkable effect made its appearance. The whole surface of the ball was covered with a purple luminescence, like that produced by the electrical excitation of the air, and caused undoubtedly by the radioactivity of the material in the ball. ... 

A second point concerning the subject of how much local sources Interfere with precipitation concerns the effect of the emission height. This came up earlier tdien we were talking about Sudbury. I had to do a few sums first to make sure of my ground, but In the case of a tall stack Injecting Into the free atmosphere above the mixed layer, pollutants might remain there for a considerable period. At this latitude radioactive fallout studies Indicate residence times of as much as ten days. But a cloud gets much of Its air from the mixed layer. 

The 95 Quantile X/Q at 3000 m for a ground release with wake as calculated by the MACCS2 code is 5.16E-05 sec/m at 3000 m and 1.16E-03 secern at a distance of 300 m, yielding a X/Q ratio of. 044. Thus, the calculated bounding dose at 3000 meters is. 044 (1 rem) or 44 mrem. The DOE calculated dose and this dose that is derived from it include dose contributions from committed effective dose for 50 years (CEDE) and immersion in the radioactive plume (cloud shine). This potential dose consequence represents a conservative upper bound on the public dose since the maximum radiological inventory corresponding to HC2 levels was used in the analysis, and no mitigation of the release was taken into account. 

The damage caused by the atmospheric dispersion of radioactive material may be the result of ln<]iury of people or the contamination of property. The Injury type of damage may be further categorized as those Injuries which result from direct exposure to the cloud of contaminants (direct effects) and those which result from material deposited on the ground (Indirect or residual effects). 

As uranium has a density almost 70% higher than that of lead, ammunition made from this metal is an effective anti-tank weapon. When used in combat, the uranium in the bullet ignites upon impact and a cloud of uranium oxide dust is formed. To reduce the radiation risk, depleted uranium (DU) is used in weapon systems of this type. It is obtained as a residue when natural uranium has been enriched in respect of uranium-235. DU is a substance that is only about half as radioactive as natural uranium. But due to its radioactivity - even if it is low - the dust can cause internal injuries if it is inhaled or ingested. 

Unlike the forms of radioactive decay that we have discussed so far, electron capture involves a particle being absorbed by instead of emitted from an unstable nucleus. Electron capture occurs when a nucleus assimilates an electron from an inner orbital of its electron cloud. Like positron emission, the net effect of electron capture is the conversion of a proton into a neutron. 

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