Abstract
The aims of this article is to estimate the dose of gamma-emitting radionuclides resulting from the atmospheric release of radioactive material Iodine-131 from an accident at two nuclear facilities simultaneously. HotSpot Health Physics Codes 3.1.2 software was utilized for this purpose. Monitoring the dispersion of Iodine-131 in the atmosphere after an accident in nuclear installations is essential for nuclear safety. This monitoring involves not only the amount of material that will be released, but also understanding its dispersion in the atmosphere and the areas that may be affected. The data collected form such monitoring is extremely relevant to assess accumulation, exposure and its consequences, as well as in making decision about mitigation requirements in contaminated sites. In this article, data from a hypothetical Loss of Coolant Accident (LOCA) at two Pressurized Water Reactor (PWR) nuclear power plants were used in order to study the behavior of radioactive plumes in the event of radiation release into the atmosphere of both plants. The results show that in most of the tests carried out, the Gaussian model used for plume modeling assumed different values and fluctuations, directly related to the atmospheric stability class. This factor influenced the estimate of the final dose. The atmospheric stability class F (moderately stable) stood out in tests conducted, as it influenced the formation of narrower plumes, and, resulted in higher dose concentrations. Consequently, there is a greater risk of manifestation of the symptoms of acute irradiation syndrome depending on the absorbed dose.
