Radiological risks assessment of building materials ingredients: Palm oil clinker and fuel ash

Technical benefits relevant to the use of palm oil clinker (POC) and fuel ash (POFA) in building materials has been well documented. However, the radiological health hazards caused by the incorporation of POC and POFA as an ingredient of building materials have not been studied so far. The radioactivity levels were measured by γ-ray spectrometry using hyper-pure germanium (HPGe) detector. The activity concentration of 226Ra and 232Th in POC and POFA was found to be in the ranges of 5.56？±？0.23 to 9.03？±？0.21 and 4.21？±？0.03 to 7.98？±？0.19 Bq kg？1, respectively, and these values were lower than the world average values of 50 Bq kg？1 for building materials. The 40K value was within the range of 413.01？±？1.78 to 604.66？±？2.18 Bq kg？1. Several radiological parameters and hazard indices, i.e. radium equivalent activity, absorbed dose rate and annual effective dose etc. were calculated for the evaluation of the potential radiological hazards. The obtained values fall within the recommended limit set by various international organizations. Since the activity levels of 226Ra, 232Th and 40K in POC and POFA were significantly lower than the corresponding literature data for other ingredients of building materials, it indicates that POC and POFA are safe to be used in concrete construction