Radiological Analysis of Suitability of Kitui South Limestone for use as Building Material

Abstract

Indoor exposure arises from the soils from which the building stands and the building materials used for construction. This is because all building materials contain certain levels of natural radionuclides 238U, 232Th, and 40K. Limestone is the most commonly used building material in Kenya due to its availability and low cost. The limestone from Kitui South has not been mined to process for use but limestone mining and processing plants were being set by the time of this study. This study therefore aimed at evaluating the suitability of the limestone for use as a building material before its mining and processing begins. The activity concentrations of the limestone samples were determined and the radium equivalent, external hazard index, gamma activity index and alpha index evaluated. The results showed that the radium equivalent activity for all the samples was below the recommend limit of 370Bqkg-1 and all the radiation hazard indices were below a unit. Therefore, the limestone can be used as building material or for manufacture of building materials without any restrictions.