Радиационная гигиена (Jan 2020)
Estimation of the equivalent dose rate of gamma radiation in the open territory of the city of Voronezh
Abstract
The aim of the study was to identify patterns of distribution of the magnitude of the the equivalent dose rate of gamma radiation in an open area of urban space, depending on the functional purpose of the inner-city territory and the type of artificial coating. Materials and methods. Measurements of the equivalent dose rate of gamma radiation (gamma background) in the city of Voronezh were carried out at 70 points, conventionally classified by functional use (industrial area, transport area, residential area, recreational area), as well as the type of coverage in open areas (granite stone blocks , asphalt pavement, paving slabs, open ground) For carrying out radiation monitoring, a highly sensitive portable search device was used – a search measuring gauge microprocessor ICP-PM1401MA. To assess the reliability of differences in the average values of the indicator by functional inner-city zones and types of artificial turf, the methods of parametric statistics (Student’s criterion) are used. Parametric methods of statistics in comparison with nonparametric methods allow statistically unambiguous interpretation of the results. There is no need to use other statistical tools in this regard. Results. The results of the evaluation of the radiation background show that the equivalent dose rate of gamma radiation (gamma background) in the city of Voronezh is from 0.06 to 0.14 µSv / h and it does not exceed the permissible value (0.3 µSv / h). Significant differences in the average values of indicators in the industrial, transport, residential functional areas in relation to the recreational area were not found (tcalc. < ttabl., P < 0.05). The maximum levels of gamma background (0.09-0.14 µSv / h) in the territory of the city of Voronezh were found in those places where processed natural stones (granite) were used for the improvement of the territory. When solving the problem of identifying the dependence of the indicator of the equivalent dose rate of gamma radiation in an open area of an inner-city space on the type of coating, in order to reduce uncertainties in the future, it is necessary to take into account the formulation of materials, especially the fraction of granite chips.
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