How radon gets into a home, and how it is stopped.
Radon gas
Invisible, odourless, radioactive
It rises from the ground under every home. Only a test shows how much gets in.
Click a county or council area to see its radon figures.
Share of tested homes at or above 200 Bq/m³. Zone borders are approximate.
Radon barrier
Ground gas kept out of the home
A sealed barrier under the floor and up the walls turns radon away before it can get in.