Radon Gas Check
Check any UK property for radon gas risk. Radon is a naturally occurring radioactive gas and the second leading cause of lung cancer in the UK — check before you buy.
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Radon Gas FAQ
What is radon gas?
Radon is a naturally occurring radioactive gas produced by the decay of uranium in rocks and soil. It seeps into buildings through foundations and can accumulate to dangerous concentrations indoors. It is odourless, colourless, and tasteless — undetectable without specialist testing.
Where is radon risk highest in the UK?
Radon levels are highest in areas with granite and limestone geology — including Devon, Cornwall, Somerset, Derbyshire, Northamptonshire, and parts of Scotland and Wales. The UK Health Security Agency (UKHSA) publishes radon potential maps based on geological surveys.[2]
Does radon affect property value or mortgages?
High radon levels can affect property value and some lenders may require evidence of remediation in high-risk areas. Sellers should disclose known radon issues on the TA6 form. Remediation — typically a sump pump or underfloor ventilation — costs £500–£2,500.
What radon level is safe?
The UK action level is 200 Bq/m³[1] (becquerels per cubic metre). Properties above this level should be remediated. The target level for new buildings is below 100 Bq/m³. A professional radon test (typically 3 months with a passive detector) gives an accurate reading.
Sources
Further reading
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Free to startExact radon class (1–7) and the estimated percentage of homes in that 1km grid square exceeding the UK action level of 200 Bq/m³.
Structured as JSON · queryable by UPRN or postcode · ready to embed in any application
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Real values — distances, concentrations, counts — not rounded ratings
29M+ UK properties
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