It could be weeks until a decision is made on whether the new icebreaker, RSV Nuyina, can safely fit under Hobart's Tasman Bridge.
Hobart's Antarctic icebreaker has had to travel to Burnie in the state's north-west to refuel instead of doing so at Hobart's Selfs Point, because it does not have approval to go under the Tasman Bridge.
The 160-metre-long, European-built Antarctic research and resupply vessel cost more than $500 million and departed Hobart on its maiden voyage to the frozen continent in December.
TasPorts executive officer Anthony Donald said the risk of going under the Tasman Bridge was still being assessed.
"When a new vessel enters a Tasmanian port, TasPorts is committed to undertaking appropriate risk assessments," Mr Donald said.
"Where a vessel is bespoke, such as the RSV Nuyina, further rigour is required, including the completion of industry-leading assessments and simulations.
"This is particularly critical when a vessel has a requirement to transit the Tasman Bridge.
An Australian Antarctic Division (AAD) spokesman said the vessel had been designed to fit under the bridge.
"Simulation testing using data from the delivery voyage has been used to access the impact of 'windage' — the surface area of the ship exposed to the force of the wind — when undertaking the transit in various weather conditions.
"A report by the Tasmanian Harbour Master has been presented to the TasPorts board and an independent review of the assessment has been done."
The spokesman said the Nuyina had so far refuelled at the Port of Burnie and in the Port of Hobart using fuel tankers.
"It is intended that RSV Nuyina will refuel at Selfs Point once the necessary approvals are in place," he said.
Tragedy befell the Tasman Bridge in 1975 when SS Lake Illawarra crashed into the bridge and collapsed part of it, leading to the deaths of 12 people.