Doses Analysis of Tin Slag 2 Reutilisation as Fine Aggregate Mixture in Mortar for Building Construction Using RESRAD-BUILD and Manual Calculation Methods

The tin processing and refining industry produces by-products in the form of tin slag 2. The radioactive content from uranium and thorium decay series in tin slag 2 still poses a challenge in the management or utilization of tin slag 2. Current options for managing by-products from the tin processing and refining industry, such as tin slag 2, are still limited to temporary storage. This study aims to simulate the use of tin slag 2 as a fine aggregate mixture in building mortar, particularly as a plastering material. The dose analysis of the use of mortar-tin slag 2 has been compared using two methods, simulation with RESRAD-BUILD software and manual calculations. The concentrations of measured radionuclide activity 226Ra, 228Ra, 228Th, and potassium were 5.7 Bq/gram, 16.6 Bq/gram, 14.3 Bq/gram, and 1.16 Bq/gram, respectively. These results indicate that several radionuclides exceed the limits of 1 Bq/gram as stipulated in the regulations for the uranium and thorium decay series radionuclide or 10 Bq/g for potassium. Initial screening analysis using the activity concentration index was carried out to see the risk of exposure caused by tin slag 2. The activity concentration index of tin slag 2 was obtained with a value of 90, which exceeded the reference level of 1. Simulation with RESRAD-BUILD software with scenario one room size 4x3x2.5 m, and two variations of plaster thickness (1 and 1.5 cm). With thicker plastering, the dose simulation increased, and a dose of 18.6 mSv/year was obtained. The second method, namely manual calculation according to the EN 17637:2022 standard, involves two scenarios. The first approach, mortar-tin slag 2, is made in plastering without considering other materials. The second approach is mortar-tin slag 2 as a superficial material and using other additional materials (bulk material). From the two manual calculation approaches, the highest dose was obtained at 11.24 mSv/year. Dose analysis through RESRAD-BUILD simulation and manual calculations showed a correlation with the activity concentration index, with a dose of more than 1 mSv/year. However, the dose values obtained have quite significant differences. The difference in the calculation results requires further review to determine which parameters influence it.