Across 37 years of Victorian political history, Mr Ismaili has discreetly cleaned the premier's office at 1 Treasury Place, working into the night to erase the detritus of the day's politicking.

When he started - several years after arriving from Albania in the early 1970s - Dick Hamer was in the chair. Then came Lindsay Thompson, John Cain, Joan Kirner, Jeff Kennett, Steve Bracks, John Brumby, Ted Baillieu, Denis Napthine and Daniel Andrews.

Some, he says, were nicer than others. "I think he is a very good premier" Mr Ismaili says of Mr Andrews. "He understands for the workers."

Mr Ismaili, now 69 and temporarily (he hopes) unable to work because of a shoulder injury acquired after falling down a stairway, was trusted enough that he had a security pass allowing him access to every single door in the building.

Despite working for almost four decades in the same building, Mr Ismaili has never been able to take long-service leave. Each time he was close to qualifying, his entitlements would be erased with the arrival of a new contractor.

Once again he is on the cusp of reaching seven years service needed to qualify, but the cleaning contract for 1 Treasury Place is going out to tender, meaning he is at risk of losing his entitlement.

"I should have been able to take it four times but I haven't taken it once," he said. "It's not fair."

Unlike other states, in Victoria workers often lose their long-service leave entitlements despite continuous employment at the one site.

The issue is set to come to a head on Wednesday, with cleaning and security contractors planning a march on Parliament, demanding Victoria catch up with other states by introducing a portable long-service leave scheme.

A survey of cleaners and security officers released by United Voice, the union representing about 120,000 cleaning and security workers, found that 85 per cent of those who have worked for more than seven years have never taken long-service leave.

An inquiry into the issue being conducted by State Parliament is due to hand down its final report within weeks.

United Voice Victorian secretary Jess Walsh said most workers in the business received the award minimum.

"So if they lose their jobs - which often happens when contracts change - there is nothing to fall back on, even after decades of services," she said.