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Radioactive plumes

The philosophy of public health protection used by the AEC and pursued ever since, is the use of multiple independent barriers, each a significant shield for the public. The last barrier involves the removal of people from the area over which the radioactive plume is expected to pass, interdiction of food supplies and the use of prophylaxis to reduce the iodine dose. Blood... [Pg.15]

The previous chapter described the consequences of a nuclear reactor accident. Chemical process accidents are more varied and do not usually have the energy to melt thick pressure vessels and concrete basemats. The consequences of a chemical process accident that releases a toxic plume, like Bhopal did, are calculated similarly to calculating the dose from inhalation from a radioactive plume but usually calculating chemical process accidents differ from nuclear accidents for which explosions do not occur. [Pg.333]

Figure 32.6 Chernobyl air plume behavior and reported initial arrival times of detectable radioactivity. Plume A originated from Chernobyl on April 26, 1986 Plume B on April 27-28 and Plume C on April 29-30. The numbers indicate initial arrival times 1, April 26 2, April 27 3, April 28 4, April 29 5, April 30 6, May 1 7, May 2 and 8, May 3. (From United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). 1988. Sources, Effects and Risks of Ionizing Radiation. United Nations, New York. 647 pp.)... [Pg.1683]

For the area with a 90Sr contamination density of 0.1 Ci/km2 (double the level of global fallout) the maximum length of the deposition track under the radioactive plume reached 300 km for the 90Sr contamination density of 2 Ci/km2 it reached 105 km, with a width of 8-9 km. ... [Pg.79]

Brenk, H.D. Vogt, K.J. (1981) The calculation of wet deposition from radioactive plumes. Nuclear Safety, 22, 362-71. [Pg.109]

The burning uranium heated the graphite, which also burned to release CO and CO,. About 2x10 Ci of gaseous iodine, which represented 12% of the available iodine inventory, were released into the atmosphere from the stack. The filter removed the particulate iodine (20 to 50x10 Ci). The radioactive plume was detected as far away as Germany and Norway. [Pg.462]

Chesser RK, Bondarkov M, Baker RJ, Wickliffe JK, and Rodgers BE (2004) Reconstruction of radioactive plume characteristics along Chernobyl s Western Trace. Journal of Environmental Radioactivity 71 147-157. [Pg.534]

The crew can use such instant data availability to maneuver the aircraft for locating and monitoring radioactive plumes. [Pg.325]

One radioactive plume crossed the English Channel into southern England in the early hours of 2 May, having experienced almost no rain on its tortuous 4100 km track from Chernobyl. Measurements of related activity in the air were made by the Electricity Boards, by British Nuclear Fuels pic, by the UK Atomic Energy Authority and by the National Radiological Protection Board at various sites throughout the UK. The Meteorological Office combined these with air-trajectory analyses to define the subsequent movement... [Pg.27]

An additional potential means of surveying the deposited material following the passage of a radioactive plume is by using an aircraft instrumented with a sodium iodide scintillation counter which can detect y-radiation in different wavebands and hence... [Pg.29]

Industries in the vicinity of the NPS which may be affected by the radioactive plume are advised to introduce pre-planned measures to minimise the effects of radioactive contamination and dosage. [Pg.42]

The basic analytical models of MACCS2 provide atmospheric transport, dispersion, deposition, and dose calculation for the released inventory. A Gaussian dispersion model based on the Tador-Gur parameterization is used for this SAR to provide consistency with previous safety studies on the HCF. Radioactive isotopes are allowed to decay and build up daughter activity during transport and deposition. The decay is based on an input file of half-lives and decay schemes for hundreds of isotopes. Dose pathways modeled were radioactive plume inhalation and immersion, groundshine from deposited radiation, and resuspension inhalation dose. Groundshine and resuspension inhalation pathways are very minor contributors to dose. [Pg.169]

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. [Pg.186]

Many see the commercial nuclear power station as a hazard to human life and the environment. Part of this is related to the atomic-weapon heritage of the nuclear reactor, and part is related to the reactor accidents that occurred at the Three Mile Island nuclear power station near Harrisburg, Pennsylvania, in 1979, and Chernobyl nuclear power station near Kiev in the Ukraine in 1986. The accident at Chernobyl involved Unit-4, a reactor that was a light water cooled, graphite moderated reactor built without a containment vessel. The accident resulted in 56 deaths that have been directly attributed to it, and the potential for increased cancer deaths from those exposed to the radioactive plume that emanated from the reactor site at the time of the accident. Since the accident, the remaining three reactors at the station have been shut down, the last one in 2000. The accident at Three Mile Island... [Pg.990]

A map with preselected sampling locations should be prepared. Computer modelling of the dispersion of the radioactive plume with the source term, meteorological conditions and other factors taken into account can help to clarify monitoring priorities. The populated areas projected to be the most contaminated should have priority in the monitoring. Those responsible for assessments and management should be aware, however, that dose projections are uncertain. They should expect differences between the results obtained with different computer models and should not use these projections as the sole basis for protective actions. [Pg.49]

In the immediate aftermath of the Chernobyl nuclear power plant disaster in 1986, there was concern about the amount of strontium-90, cesium-137, cesium-135, and iodine-131 in the resulting radioactive plume. Iodine-131 is a beta-minus emitter Avith a half-life of 8.0 days. Write an equation for its decay and discuss the dangers it might pose as compared with strontium-90. [Pg.376]

Doses are calculated for a hypothetical person standing outside in the radioactive plume, for 2 hours at the exclusion area boundary and during the entire period of plume passage at the low population zone outer boundary. [10 CFR 100 (d)]... [Pg.95]

Much of any particulate material in a radioactive plume would be deposited on the ground within about 50 miles of the facility. [Pg.543]

Numerous studies indicate that, beyond 2 to 3 miles of the plant, sheltering followed by post-release monitoring and relocation from "hot spots" would be as effective as evacuation for most severe accident scenarios. This might not be the case under certain meteorological conditions, in particular, if the radioactive plume passes through rainfall or if severe inversion conditions trap and confine the plume near the ground. Such conditions cannot be predicted with any useful degree of accuracy, and off-site... [Pg.558]

To begin with, the Health Physics Manager had to assume that the radioactive plume consisted of the standard fission products. This was not the case on two counts. The first is that some polonium 210 had been released and this is not a normal fission product. The polonium release is described in a later section. The other reason was that many of the fission products were not volatile, and were either contained in the pile itself or had been trapped by the filters. Thus the main component of the fallout from the chimney was iodine 131. This simplified matters considerably, since the isotope has a relatively short half-life of eight days. Iodine 131 emits both beta and gamma radiation. [Pg.114]


See other pages where Radioactive plumes is mentioned: [Pg.189]    [Pg.173]    [Pg.526]    [Pg.669]    [Pg.206]    [Pg.562]    [Pg.27]    [Pg.47]    [Pg.70]    [Pg.30]    [Pg.78]    [Pg.93]    [Pg.308]    [Pg.124]    [Pg.142]    [Pg.169]    [Pg.370]    [Pg.61]    [Pg.482]    [Pg.298]   
See also in sourсe #XX -- [ Pg.526 ]




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