Some staff are said to be considering action

It was alleged that building work at the Caithness plant had been held up by a lack of radiation cover and contractors in the decommissioning programme were said to have had to delay and reprogramme work.

However, a spokesman for Dounreay said it was "unaware" of any breakdown in the relationship between staff and management and flatly denied any threat to safety.

He said a problem had emerged on one recent occasion when there was a high sickness level, but that had been quickly resolved.

The spokesman said: "Recently, an unusually high level of sickness among the contractor's staff depleted the resources available to UKAEA under this contract for a very short period."

'Safety not compromised'

"As a result, UKAEA prioritised the available resources and this meant that a few relatively minor jobs were held up for a day or so.

"At no stage whatsoever was any essential safety cover compromised, all routine monitoring was completed and no work was done without appropriate monitoring.

"No decommissioning work was affected."

A spokesman for AEA Technology said the company was not aware of staff being disgruntled.

We are confident that AEA Technology is intending to strengthen the team with additional recruits and training of existing employees where appropriate

Trade union statement

And he added that union representatives had made no official approaches to management over concerns expressed by workers.

The Central Trade Union Co-ordinating Committee represents all trade union members in AEA Technology, including safety workers at Dounreay.

It said it "strongly repudiated" talk that unions were in dispute with AEA Techology regarding safety arrangements.

The committee made a statement on Wednesday which said: "We are aware that a number of employees have left AEA Technology at Dounreay for jobs with other employers.

"We have regular meetings with senior AEA Technology managers and have discussed this situation.

"We are confident that AEA Technology is taking positive recruitment action to replace people who have left and indeed is intending to strengthen the team with additional recruits and training of existing employees where appropriate."