Officials are "confident" Australia's new $2 billion icebreaker will fit under a Tasmanian bridge it needs to pass in order to refuel.
The RSV Nuyina icebreaker is set to replace the Aurora Australis, which left Hobart on its final voyage to a Dubai shipyard in December.
The Nuyina is being fixed after recent sea trials and is expected to arrive in Australia by September, about 14 months behind schedule.
But it's unclear if the vessel will fit beneath the Tasman Bridge, under which it needs to sail to be refuelled.
The Australian Antarctic Division, which operates under the Department of Agriculture, Water and Environment, is working with TasPorts to ensure it is safe for the ship to go under the bridge.
Australian Antarctic Division official Rob Bryson confirmed to senators TasPorts was undertaking a risk assessment.
"At this stage we still believe that we'll be able to fit under the bridge," he told an estimates hearing on Monday.
The Nuyina is currently in the Netherlands while being repaired after the ice trials.
Australian Antarctic Division director Kim Ellis said the size of the bridge had been factored into plans, noting the risk assessment would check the ship could still conduct the refuelling journey.
"We are working through now with TasPorts on that detailed assessment with the pilots to determine its ability to get under the bridge, and we're confident that will happen," he said.
"At the same time we are also looking at other ways to refuel."
Mr Ellis said there were more efficient ways to get fuel and cargo to the ship, explaining the journey to refuel would take the Nuyina out of action for up to four days.
