How to ensure that national radon survey results are useful for public health practice.

Exposure to radon gas increases the risk of lung cancer. Preliminary national survey data collected by Health Canada indicate that approximately 10% of households exceed the recommended federal long-term guideline of 200 Bq/m3. However, results to date have been reported for large geographic areas in broad measurement categories. Given that Health Canada recommends the most rapid remediation for buildings with the highest concentrations, such reporting makes it challenging for public health authorities to target interventions to communities at the highest risk. Here we use data from a survey in British Columbia to illustrate how improved spatial resolution and more refined concentration categories would be valuable for prioritizing the use of limited public health resources. We encourage Health Canada in future to provide more specific, community-level information that can be used to inform local policy and to engage building owners in radon testing and remediation.