Hunter-New England Area Health Service confirmed one staff member had gone on worker's compensation in the past week and two others had been temporarily deployed to Belmont Hospital.

The Herald understands that four employees experienced various symptoms as soon as they returned to work last week.

About 30 staff walked off the job on November 14 but returned last Monday after hospital management agreed to measures including providing staff with goggles, gowns, gloves and masks.

During the past eight months, some staff had suffered respiratory problems, unexplained rashes and headaches they believe were caused by mould.

A report prepared for the hospital stated that a sample collected at the department's Cardiff storage centre contained mould concentrations almost 50 times greater than World Health Organisation standards. It is believed the mould has spread via the medical files themselves.

Staff have complained about "substandard" goggles and difficulties communicating with face masks on.

Michael Di Rienzo, the health service's director for acute networks, said more types of goggles were now available.

He denied that staff who had fallen ill had been pressured into taking sick leave rather than going on worker's compensation as one employee, who asked not to be named, alleged.

Representatives from the Health Services Union and the hospital are meeting every week over the problem.

Mr Di Rienzo said, "we're considering anything" when asked if management had considered moving the medical records department.

"Remediating" the department was management's first priority, he said.