# Radon potential

The radon class of every 1 km square in the UK, from the UK Health Security Agency and British Geological Survey's indicative atlas of radon.

## Facts

- Published by: British Geological Survey and UK Health Security Agency
- Level of detail: 1 km grid
- Updates: Every few years
- History: Since 2022
- Licence: Open Government Licence 3.0
- Levels: Map point

## Caveats

- Each 1 km square shows the share of homes in it estimated to be at or above the radon Action Level of 200 becquerels per cubic metre, in six classes. A square takes the highest class found anywhere in it, so part of a square may be lower.
- This is an estimate for an area, from the rocks underneath and past measurements in homes. It cannot say what radon there is in any one home. Only a test can, and UKHSA sells them at ukradon.org.
- A square in class 2 or above, where 1% or more of homes are estimated to be at or above the Action Level, is what UKHSA calls a radon Affected Area.
- Great Britain is from version 3 of the atlas (2022) and Northern Ireland from version 1 (2015). The classes mean the same in both.
- A detailed report for one address is sold by UKHSA and BGS. This map is the free indicative atlas, which is less detailed.

## Sources

### Indicative atlas of radon (Great Britain and Northern Ireland)

- Publisher: British Geological Survey and UK Health Security Agency
- Licence: [Open Government Licence 3.0](https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/)
- Edition: Indicative Atlas of Radon: GB v3, NI v1
- Published: 1 December 2022
- Fetched: 19 October 2026
- Updates: irregular
- Credit: Contains British Geological Survey materials © UKRI 2022. Radon Potential classification UK Health Security Agency © Crown copyright 2022. Contains OS data © Crown copyright 2020. Contains public sector information licensed under the Open Government Licence v3.0.
- Publisher's page: https://www.bgs.ac.uk/datasets/radon-data-indicative-atlas-of-radon/

## Use it

- [The map](https://openindex.co.uk/map/radon)
- API: https://openindex.co.uk/v1/layers/radon-potential

## How to cite

Source: Open Index, openindex.co.uk. Link to this page, https://openindex.co.uk/sources/radon.

Open Index's own text and the figures it works out are licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Source data keeps its publishers' licences, named with each figure. Give each figure's period and source with it.

- Contains British Geological Survey materials © UKRI 2022. Radon Potential classification UK Health Security Agency © Crown copyright 2022. Contains OS data © Crown copyright 2020. Contains public sector information licensed under the Open Government Licence v3.0.

Snapshot 2026.10.8, https://doi.org/10.5281/zenodo.23508850. The HTML page: https://openindex.co.uk/sources/radon