A former Centrelink telephone operator who says the "despair" of the agency's clients gave him a morbid fear of telephones has lost his legal bid for workers' compensation.

Mark Grant says having to speak to 60 welfare claimants a day, who "pulled at his heartstrings" with the stress of the experience, left him with "telephone phobia" and unable to earn a living.

The former Department of Human Services public servant told the Administrative Appeals Tribunal that his six months at Centrelink in 2008 felt like a long time.

He detailed for the tribunal daily conversations he found stressful: "Young people who were unable to get jobs pulled at his heart strings, people would say they were unable to pay the rent, let alone pay to travel to a job interview; people who were relying on the generosity of friends."

Mr Grant told tribunal member Naida Isenberg there was also an element of aggression in some of the calls, although she said there was no evidence he complained to his bosses about any specific threats or abuse.