HMP Dartmoor: Prison to be temporarily closed and inmates moved due to radioactive gas

HMP Dartmoor is being closed temporarily and its inmates moved elsewhere, the Ministry of Justice has confirmed.

Around 175 inmates are to be moved from the category C men’s prison in Devon over the next two weeks after the discovery of high levels of radon at the site.

At the end of 2023, high levels of radon – a colourless, odourless radioactive gas – led to more than 400 inmates being removed from the jail.

Prisoners had begun returning to Dartmoor at the start of July, before this latest incident forced the complete closure of the prison.

Steve Gillan, general secretary of the Prison Officers’ Association (POA), said conditions at Dartmoor had “deteriorated” since the decision to return prisoners to the jail, but the closure was “the correct decision”.

He added: “The POA know this has come at the worst possible time with overcrowding and this could make matters worse, but there is no other option.”

While the Ministry of Justice believes there is enough capacity to cope with the temporary closure of HMP Dartmoor, the relocation of its inmates will place further strain on an already stretched prison system.

A spokesperson for the department said: “Our prisons are in crisis. This is the most recent illustration of why this Government was forced, in its first week, to take urgent action to release pressure on the estate.

“It is also why we are committed to building new prison places to lock up the most dangerous offenders and protect the public.”

The incident comes on the same day the Government laid regulations in Parliament to reduce the amount of time prisoners must spend in jail before they are automatically released from half of their sentence to 40%.

The move – which does not apply to those convicted of sex offences, terrorism, domestic abuse or some violent offences – follows a speech by Justice Secretary Shabana Mahmood last week in which she warned failing to take action would result in the “collapse” of the prison system.

Figures published on 12 July indicated there were barely 700 places left in the adult male estate - well below the buffer the Ministry of Justice believes is necessary to ensure prisons can cope with shocks such as the closure of HMP Dartmoor.

Built in the early 19th century to hold French prisoners during the Napoleonic Wars, HMP Dartmoor had been slated for closure in 2023, but that decision was reversed in 2019 in the face of rising prisoner numbers.