Comparative analysis of factors influencing the measurements of DDL-2 and RAD7 radon monitors

Based on the parallel observational data from the DDL-2 and RAD7 radon monitors at well Anguo-1 in Pingliang, Gansu Province, this study systematically analyzes the influence of different sampling methods on DDL-2 instrument measurements by integrating traditional statistical methods (including Pearson correlation analysis and coefficient of variation calculation) with machine learning algorithms (including random forest regression and Isolation Forest anomaly detection). This study identified and evaluated the effects of key environmental parameters (temperature, humidity, and atmospheric pressure) on the measurement accuracy of the DDL-2 instrument and compared the long-term stability of the domestic DDL-2 radon monitor with that of the imported RAD7 radon monitor. The results indicate that temperature and atmospheric pressure had relatively significant effects on the precision of DDL-2 radon measurements. The adoption of standardized sampling methods and controlled observation conditions can substantially reduce primary duplicate-sample errors in DDL-2 measurements, bringing the stability of DDL-2 measurements to levels approaching those of the RAD7 instrument. Well Anguo-1 in Pingliang, Gansu Province, was used as a case study to evaluate the applicability of the DDL-2 radon detector in seismic monitoring, providing a scientific basis for data quality control and standardized operation of domestic radon detectors.