Indoor residential radon concentration measurements using CR-39 detectors across different countries. Review

Indoor radon measurements using CR-39 detectors: a review of the technique Indoor radon measurement with CR-39 detectors is well known now to be a reliable and efficient method for long term, passive monitoring of indoor radon in dwellings. The reviewed studies carried out in several countries showed wide ranges of indoor radon levels depending on geological formations, type of soil, building materials and types of dwelling. By far the majority of studies had consistent results concerning radon levels in lower rooms inside homes, such as basements and ground-floors which are generally expected to have higher radon values, due to their proximity to soil with low air exchange rates. Seasonal variability was also indicated, as higher radon activity concentration results were obtained when less ventilation occurred (cold period) and soil gas was driven by pressure. Furthermore, age of building, structural cracks and use of locally produced construction materials were found to be significant contributors towards radon enrichment indoors. Regarding the variations in dwellings, although most of the studies reviewed presented average values below international reference level (WHO 2009), a portion retreated to action levels and it demonstrated that there are potential health risks for long-term exposureOn the whole, the findings reveal that CR-39 is a suitable passive detector technology for national domestic radon surveys and provide further justification to continue monitoring, improve mitigation techniques and conduct more research in other areas to build regional indoor radon concentration databases aiming at supporting as well planning regulations.