Charlie Ginty was handing out how-to-vote cards for Labor when the incident occurred.

"We had to lift them in. They could build a temporary ramp there, it's not that hard to do," he said.

The centre has been declared wheelchair inaccessible after it failed eight criteria on an inspection in February.

Divisional returning officer Sandra Taylor said they had been unable to find a building in Orange for a short-term lease that was fully accessible and met other needs including providing parking.

"I looked at probably four or five buildings. Finding a fully accessible building in Orange was difficult," she said.

Ms Taylor said they would look at providing a ramp.

She said people could also vote from inside their car as electoral officers would bring the voting forms out to them.

Voting for people with a valid reason not to vote on May 18, is open for three weeks.

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