Radiogenic heat production and NORM budgeting of construction rocks in the Kurdistan Region, Iraq

This study examines the radiogenic heat production (RHP) of 23 rock samples that are frequently used as primary construction materials in Kurdistan Region of Iraq. The activity concentrations of 238U, 232Th, and 40K were measured using a gamma-ray spectrometric system with a (3‘× 3’) NaI(Tl) detector. The RHP of the samples has been found to range from 0.466 to 1.124 µW m−3, with an average of 0.754 µW m−3. The results show that these values are typical for sedimentary and low-grade metamorphic rocks of the crust. The analysis of relative contributions by elements indicates that Uranium and Thorium are predominant contributors to the radiogenic thermal budget, with 49.3% and 44.0%, respectively. Potassium contributes only a small amount at 6.7%. From a thermal standpoint, the thermal energy produced by uranium and thorium has no material impact on the indoor microclimate of buildings. However, the study emphasizes RHP as an important indirect geochemical proxy for radiological safety since there exists a very strong positive relationship between Uranium concentration and RHP, which indicates an increased likelihood of radon emanating from samples with high RHP values than from those with low RHP values. These results will add to the regional geophysical database and highlight the need for urgent screening methods for construction materials to protect the public from chronic radiation exposure through improper radiological safety practices.