Evaluation of consumer digital radon measurement devices: A comparative analysis.

Kansas State University (KSU) Engineering Extension conducted an abridged evaluation of eight consumer grade digital radon monitors. Using the KSU secondary radon chamber, these devices were exposed to three different radon concentrations for 7 days in average household temperature and relative humidity conditions. The three different radon concentration ranges used were: 12.8 pCi/L to 15.5 pCi/L (473.6 Bq m-3-573.5 Bq m-3), 27.7 pCi/L to 29.4 pCi/L (1024.9 to 10857.8 Bq m-3) , and ambient room level average radon concentration of 0.6 pCi/L (22.2 Bq m-3). The American National Standards Institute/American Academy of Radon Scientists and Technologists Performance Specifications for Instrumentation Systems Designed to Measure Radon Gas in Air (ANSI/AARST MS-PC)[7] minimum performance metrics were used to evaluate the accuracy and precision of each model type for each radon concentration tested. The eight different device models performed within the 0 ± 25% requirement for the Individual Percent Error (IPE) for radon concentrations between 27.7 pCi/L and 29.4 pCi/L (1024.9 to 10857.8 Bq m-3). For radon concentrations between 12.8 pCi/L and 15.5 pCi/L (444 to 592 Bq m-3) and ambient room radon concentrations, seven of the eight monitors fell within the IPE ANSI/AARST MS-PC minimum performance requirement[7] ranges. All eight device models fell within the ± 15% ANSI/AARST MS-PC minimum performance requirement [7] Coefficient of Variation (CV) range for radon concentrations between 12.8 pCi/L and 15.5 pCi/L (444 to 592 Bq m-3) and for radon concentrations between 27.7 pCi/L and 29.4 pCi/L (1024.9 to 10857.8 Bq m-3). In the future, evaluating the performance of these models over time to observe their long term accuracy and precision is anticipated. &#xD.