Abstract
Monazite contains natural radionuclides associated with the natural radioactive series of uranium and thorium. The objective of this study is to ascertain the ef fect of monazite concentration on radioactivity concentration of mortar cement as a building material. Six ratio of cement–monazite was analyzed for radioactivity concentration using an HPGe gamma spectrometer. The radiological parameters such as radium equivalent, hazard indices, gamma index, and annual ef fective dose were calculated. The radium equivalent in the samples ranged from 34.34 Bq/kg to 796.81 Bq/kg, while the external hazard index varied from 0.09 to 2.14, and the internal hazard index ranged from 0.15 to 2.83. The gamma index exceeded unity in samples containing monazite concentrations of 0.016% or lower when mixed with sand in mortar cement. The average annual effective dose rate varied between 0.07 and 1.76 mSv/year. The results of this study demonstrated that as the monazite
concentration increased, the concentration radioactivity increased for all practical purposes. The obtained information data will be used to design and develop the radiation shielding materials and compounds in the further study.
