Metrology for Indoor Radon Measurements and Requirements for Different Types of Devices

Abstract

Indoor radon measurements have been conducted in many countries worldwide for several decades. However, to date, there is a lack of a globally harmonized measurement standard. Furthermore, measurement protocols in the US (short-term tests for 2–7 days) and European Union countries (long-term tests for at least 2 months) differ significantly, and their metrological support is underdeveloped, as clear mathematical algorithms (criteria) and QA/QC procedures considering fundamental ISO/IEC concepts such as “measurement uncertainty” and “conformity assessment” are still absent. In this context, for many years, the authors have been advancing and refining the theory of metrological support for standardizing indoor radon measurements based on a rational criterion for conformity assessment within the ISO/IEC concepts. The rational criterion takes into account the main uncertainties arising from temporal variations in indoor radon and instrumental errors, enabling the utilization of both short- and long-term measurements while ensuring specified reliability in decision making (typically no less than 95%). The paper presents improved mathematical algorithms for determining both temporal and instrumental uncertainties. Additionally, within the framework of the rational criterion, unified metrological requirements are formulated for various methods and devices employed in indoor radon measurements.

Assessment of Indoor Radon Gas Concentration in Latvian Households

“…The impact of ventilation systems on radon concentrations was also evident, with the buildings employing mechanical ventilation demonstrating lower radon levels compared to those relying on natural ventilation. Effective ventilation systems can help reduce radon levels in premises by diluting indoor air with outdoor air, thereby decreasing the concentration of radon gas [30,[33][34][35][36]. Properly designed ventilation systems can also create positive pressure indoors, preventing radon from entering through cracks and gaps in the building.…”

“…Uncertainty in measurements can arise from multiple aspects, leading to heightened levels of uncertainty in definite cases. Uncertainty involves deviations in indoor radon concentrations from annual averages, measured in various conditions across numerous buildings, also accounting for the influence of both natural and human-related factors, such as seasonal fluctuations in indoor radon levels and duration of measurements [34].…”

Investigation of the Performance of Various Low-Cost Radon Monitors under Variable Environmental Conditions

“…Quality control in radon measurement is of utmost importance to ensure reliable results. Quality assurance activities, such as intercomparison between different devices, calibration in radon chambers, or comparison of controlled versus variable conditions, are crucial elements in this process [ 5 , 6 ]. Initiatives such as the European metrological project Metrology for Radon Monitoring (MetroRADON) have emerged as pillars to establish standards and protocols for radon measurement, providing a solid basis for data validation and comparison [ 7 ].…”