Unsafe levels of cancer-causing radon gas detected at 16 UK prisons

Unsafe levels of cancer-causing radon gas have been detected in 16 prisons in the UK, with 33 sites under investigation by the Ministry of Justice (MoJ), Report informs referring to The Independent.

HMP Dartmoor in Devon was closed in 2024 after levels of radon up to 10 times higher than the recommended limit were recorded in some areas. Hundreds of former prison staff and prisoners have signed up to a group legal action against the MoJ seeking compensation over their exposure.

Now The Independent can reveal that HMP Bedford, Channings Wood, Downview, East Sutton Park, Exeter, Hollesley Bay, Leicester, Lincoln, Lindholme, Parc, Portland, Stafford, The Verne, Usk and Wealstun have all measured unsafe levels, deemed "above action" levels by officials.

Radon is a colourless, odourless radioactive natural gas, formed when small amounts of uranium in rocks and soils decay, and can build up in indoor areas. While it can be controlled through ventilation, it is known to increase a person's risk of lung cancer, with more than 1,100 deaths from the disease attributed to radon each year in the UK, according to the Health Security Agency.

Symptoms of radon poisoning include wheezing, fatigue and coughing up blood.

By law, mitigation measures must be put in place to reduce radon exposure in workplaces if levels are shown to exceed 300 bq/m³, averaged annually. For sleeping areas, such as prison cells, this is lowered to 200 bq/m³, according to UK health security agency guidance.

As well as the 16 sites with unsafe levels, a separate site within the boundaries of HMP Lindholme, near Doncaster, has also measured above action levels of radon gas, along with 16 probation sites across London, the South East, South West, Wales, the North West, East Midlands and the East of England.

The number of sites measuring high for radon was uncovered in meeting notes recorded by the Prison Officers Association (POA) in early 2024. The MoJ said this week that, of the 33 investigations sparked by the worrying levels of radon, a small number were still awaiting final sign-off or under review.

A prison service spokesperson said that they "take steps to actively mitigate the risk posed by radon in line with health and safety regulations."