Collocation testing of consumer-grade electronic radon sensors in Canadian homes

Radon exposure is the second leading cause of lung cancer in Canada. Consumer-grade electronic radon sensors, which provide real-time results, are increasingly used by homeowners for radon monitoring. This study evaluates the short-term performance of four consumer-grade radon sensors (RadonEye, Inkbird, Spirit, and Wave) against a professional-grade instrument (RAD7) in seven different Canadian homes. In each home, testing was conducted for seven days with radon concentrations ranging from negligible to more than 2000 Bq/m 3 . Sensor performance was assessed using a total of six analysis methods, including linear regression, RMSE, Pearson or Spearman correlation analyses, Welch’s t-test or Mann-Whitney U-test, Bland-Altman plots, and confusion matrices. The results reveal that three of the four sensors had similar performance across most analysis methods, while one sensor had the lowest performance, possibly attributed to the short testing duration. For occupants, these sensors can be useful for quickly detecting current radon levels; however, long-term testing (90 days) with certified passive detectors is still recommended to ensure a reliable assessment of their radon exposure.