Annual mean residential radon concentration (population-weighted)

Radon is a naturally occurring radioactive gas that can accumulate indoors, especially in homes with certain geology and ventilation patterns. Long-term exposure increases lung cancer risk, and radon is often cited as the second-leading cause of lung cancer after smoking in many countries.

This statistic reports a country’s population‑weighted annual mean residential radon concentration, expressed in becquerels per cubic meter (Bq/m³). It’s a useful “hidden health risk” indicator because high radon levels are largely invisible without testing, yet mitigation (e.g., sub-slab depressurization, improved ventilation) can substantially reduce exposure.