ACCURACY AND PRECISION OF RAD7 AND RAD HSUB2/SUBO ACCESSORIES RADON DETECTOR IN WATER MEASUREMENT BASED ON COUNTING STATISTICS FOR SNIFF AND NORMAL MODES

摘要

Many biological risks may occur due to radioactive elements through drinking water, reason for which it is very important to investigate the precision and accuracy of radon measurements in such sources. The concentrations of radon were measured in commercially available drinking waters sourced from water wells in the Arar city (Saudi Arabia) in winter season of 2017. Two methods of measurement were used for this study: NORMAL mode and SNIFF mode, for both using RAD7 and RAD HSUB2/SUBO accessories. The uncertainty value (2σ) of the mean activity concentration of radon for SNIFF mode was decreased from 32% for one-hour cycle to 8% for 72 hours cycle, while for NORMAL mode measurement the 2σ decreased from 25% for 1 hour cycle to 6% for 72 hours. The results showed that the average values of radon concentrations of studied water sources were more accurate and precise using NORMAL mode than using SNIFF mode, due to the decrease of 2σ when switched from the SNIFF mode to NORMAL mode. Therefore, further studies are recommended in order to investigate in more detail the standardization and calibration processes of RAD7 in radon measurements using different techniques.