This study aimed to enhance the reliability of measured data and establish a quantitative quality control strategy by implementing a real-time measurement uncertainty assessment function in a beta attenuation-based particulate matter (PM10) continuous...
This study aimed to enhance the reliability of measured data and establish a quantitative quality control strategy by implementing a real-time measurement uncertainty assessment function in a beta attenuation-based particulate matter (PM10) continuous ambient air monitoring instrument. In conventional measurement systems, only concentration values are displayed. In this study, a system was developed to calculate and display measurement uncertainty in real time alongside concentration values. The uncertainty assessment was designed based on the GUM(Guide to the Expression of Uncertainty in Measurement), by establishing a measurement model, estimating the standard uncertainty and degrees of freedom for each input variable, and combining them to compute the combined standard uncertainty, effective degrees of freedom, and ultimately the expanded uncertainty in real time. The system was applied and evaluated in ambient air conditions during winter and spring. The results showed that measurement uncertainty increased and fluctuated more sharply at higher concentration levels, indicating distinct variation patterns by concentration range. Contribution analysis identified five key input variables that significantly influenced the overall uncertainty, and variations in uncertainty were also observed depending on environmental conditions such as temperature and humidity. Furthermore, a comparison with the conventional mean ± standard deviation method was conducted to explore the structural characteristics and practical applicability of the real-time measurement uncertainty. This study presents a new quality control approach that provides uncertainty information simultaneously with measurement, and suggests potential for future expansion into advanced models applicable to various air pollutants and environmental conditions.