This study evaluates natural radioactivity levels in building materials used in Penang, Malaysia. Soil, cement, and brick samples were analyzed for radionuclides U-238, Th-232, and K-40 using High Purity Germanium (HPGe) gamma spectrometry. Samples were stored airtight to ensure radioactive equilibrium before measurement. Results showed that concentrations of U-238, Th-232, and K-40 were below global reference values recommended by NCRP and UNSCEAR. Cement bricks recorded the highest radionuclide concentrations and radiation hazard indices, including Radium Equivalent Activity, internal hazard index, and external hazard index, while waterproofing cement had the lowest. Raeq values for all samples were below the safety limit of 370 Bq/kg, and annual dose rates were under 70 μSv/year, meeting European Commission guidelines. Granite and sand soils exhibited lower radionuclide concentrations compared to global averages, except for K-40 in granite soil, which exceeded values reported in other studies. While all materials remain within safety thresholds, elevated radiation levels in cement bricks warrant further consideration. This study offers valuable insights into radiological hazard analysis, supporting sustainable building practices in Malaysia. • Ra-226, Th-232, and K-40 in building materials are below global safety limits. • Cement Brick had the highest Ra-226 (14.21 Bq/kg) and K-40 (183.16 Bq/kg), while Paver Brick had the lowest levels. • Portland Cement showed the highest Ra-226 and Th-232 among cements. • Radiation indices (Hin, Hex) and annual dose rates were within international safety standards.
Mohamed et al. (Sun,) studied this question.