The Wollongong couple has recently returned from a two-month stint on Africa Mercy, the world's largest charity hospital ship that provides health care to developing nations.

Manned by volunteer health-care professionals and run by charity organisation Mercy Ships, the 16,000 tonne vessel accommodates 7000 free surgeries a year.

This year the ship is docked in the West African country of Sierra Leone, a nation recovering from the devastation of civil war.

Kathy volunteered her services as a pathology technician while Mike, a funeral worker and retired police officer, joined the ship's housekeeping crew.

The couple, both aged 56 and the parents of two adult daughters, said their decision to volunteer emerged out of empty nest syndrome.

"As the girls were leaving home, we asked ourselves, 'What now?' We weren't going to just work ourselves into retirement then follow everyone else around Australia," Mrs Rossiter said.

But the decision was a major undertaking that involved securing two month's leave from work and self-financing the entire trip.

Mrs Rossiter said that while Sierra Leone had emerged from a decade of civil war in 2002, the devastation was ever present.

A lasting feature of the war, in which tens of thousands died, was the atrocities committed by the rebels, whose trademark was to hack off the hands or feet of their victims.

"One woman who was spoken about had a choice of losing her hands, feet, buttocks or breasts," Mrs Rossiter said.

"She chose her feet and buttocks. I saw photos where she was being fitted with prosthetic feet and they did corrective surgery to restore her shape from the butchering of her buttocks.

"A lot of the people today have seen family members maimed or killed in front of their eyes."

Mrs Rossiter said that aside from the psychological trauma, other problems included a high rate of poverty and unemployment that left people unable to finance medical procedures.

"We were doing facial reconstructions, where tumours had eaten faces, fixing cleft palate, bilateral cleft palate, cleft lip - life-saving surgeries that are just not affordable," she said.