Sellafield partially closed over safety concerns

The Sellafield nuclear plant in Cumbria has been given the all-clear after an investigation into higher-than-normal radiation readings detected at a perimeter fence.

The monitoring system picked up "elevated" levels of radioactivity overnight, leading to workers being told to stay away.

But following an analysis by safety staff, Sellafield said the levels were "naturally occurring background radon".

The company is still trying to establish exactly why the alarm was sounded even though it has now established the cause.

The Prospect union, which represents 5,000 nuclear specialists at Sellafield, said the elevated radiation readings were within acceptable limits and were not a danger to human health or to the plant.

Day operations were suspended at the Sellafield nuclear site this morning after higher than normal radiation readings were detected at a perimeter fence.

The company are investigating and stress there is no danger to the public or employees.

Tim Backshall sent this report.

The World Nuclear Association, which promotes civil nuclear energy, reports that Sellafield has put the elevated radioactivity reading down to "variations in natural background".

Sellafield Ltd have confirmed that the radioactivity detected by one of the site's monitors overnight was the result of "naturally occurring Radon", and not because of any issue or problem at the site.

Working operations are continuing and the day staff sent home today are due back in on Monday as normal.

There are unconfirmed reports that the alert triggered at Sellafield nuclear site this morning was the result of naturally occurring radium.

A meeting with bosses is getting underway shortly.

Irish officials have been in contact with Britain over raised levels of radioactivity at the Sellafield nuclear reprocessing plant, the government has said.

Only around 112 miles (180km) separates the nuclear site from the coast of Ireland.

"Officials from the Department of the Environment have been in contact with their UK counterparts ... and will receive updates throughout the day," the Irish government said in a statement.

The Nuclear Decommissioning Authority (NDA) has said it is too early to say whether there is a leak at the Sellafield site, but stressed that there was no danger to the public.

It added that it is still not clear where the radiation is coming from.

Professor Richard Wakeford, professor of epidemiology at the University of Manchester, has said that the level of radioactivity detected at Sellafield is not above that "encountered in everyday life".

One Sellafield worker told the Press Association that an air sampler on a perimeter fence had detected a problem, which led to staff being told to stay away.

It is understood nothing has been detected inside the plant.