Radon is a naturally occurring radioactive gas.
It can be harmful to health because it produces tiny radioactive particles in the air we breathe.
Radiation from these particles can damage our lung tissue, and over a long time may cause lung cancer.
Every building has radon and in most areas the levels are low. Some buildings in radon affected areas have higher levels. Buildings in these areas should be tested for radon. High levels can be reduced by simple building works.
UKradon provides more advice and maps to check if you're in a radon affected area.