Certain parts of the UK are more at risk of this radioactive gas, which has no smell, taste or colour but can cause serious health problems for people living in properties with higher than acceptable Radon levels.

Radon penetration occurs in many thousands of homes in the UK, predominantly in the East Midlands and the South West but there are pockets just about everywhere across the UK.

Believe it or not, there are up to 900 chemicals in indoor air. Not only this, but according to the Environmental Protection Agency, indoor air is found to be up to 70 times more polluted than outdoor air.