Radon in HMP Dartmoor – group claim

We were approached by a group of prisoners in February 2024 who were concerned about exposure to radioactive particles of radon in HMP Dartmoor. It did not take us long to realise that this was an extraordinary story involving hundreds, possibly thousands of prisoners, nurses, prison officers and others.

We made FoIA requests for disclosure and involved experts. The lawyers acting for the Ministry of Justice repeatedly refused our requests to have the premises of Dartmoor prison surveyed by an independent expert and establish the concentration of the decaying radon particles in the air and water.

In the meantime, the numbers grew, and HSE initiated a criminal investigation against the senior managers of this prison, Dartmoor prison chiefs under criminal investigation over handling of radon scare. We served a pre-action letter, and HMP Dartmoor was closed in July 2024.

This case received significant media attention – see the articles in the Guardian Doncaster prisoners could sue government over exposure to radon gas | Prisons and probation | The Guardian and Dartmoor Chronicle Prison staff and inmates sue over radon gas exposure | Dartmouth Chronicle.

BBC reported about radon in Dartmoor on 28 June 2024 Staff’s ‘health fears over radiation’ at HMP Dartmoor – BBC News , 23 September 2025 Dartmoor prison staff and inmates sue over radon gas levels – BBC News and 17 October 2025 High radon levels at Dartmoor Prison found 13 years earlier – BBC News

These articles prompted a number of enquiries from the serving and former prisoners, their families, prison officers and nurses, as well as the families of the deceased prisoners and staff members. Disclosed evidence, which is in the public domain, shows that in some parts of Dartmoor had levels of radon were 14-15 times above the legal limits.

Radon is the second biggest cause of lung cancer (Radon) and has the potential to cause or accelerate other types of cancer. It can also cause other serious lung and other medical conditions. Several hundred claimants have instructed us to issue proceedings against the Ministry of Justice.