Spatial Distribution Analysis and dose Assessment of the Radon Emitted from the Monazite-Containing Mattress in General Residential Space by CFD Methods

Abstract

Recently, mattresses produced from radon-emitting monazite raw materials in the manufacturing process were found to be releasing radon, and a survey by the Korean Nuclear Safety and Security Commission indicated that some of these products exceeded safety standards. In this study, the distribution of the radon resulting from radon-emitting mattresses was evaluated. The computational fluid dynamics (CFD) code FLUENT was used to analyze the distribution of radon in a general living space, and to assess the exposures of residents. Drawings from the Korea Land and Housing Corporation were analyzed to determine the layout and geometry of the general residential space. Based on the results of the CFD simulation, the distribution of radon in the general residential space was analyzed based on the direction of ventilation and distance from the source. The dose was evaluated to analyze the radiological safety, and was determined to be less than 0.101 mSv per year. These results were in accordance with the reference level of 10 mSv from the International Commission on Radiological Protection recommendation and the annual dose limit of 1 mSv per year for processed products in South Korea.