Australian authorities have banned Qatari-owned bulk carrier Maryam from entering any Australian port for three years after major safety and maintenance issues were identified along with crew welfare abuses.
The International Transport Workers' Federation, which represents hundreds of transport workers' trade unions worldwide, says the Maryam was detained in Port Kembla in Wollongong in February.
Inspections by the Australian Maritime Safety Authority identified 36 safety, crew welfare and maintenance breaches, with 23 seafarers owed tens of thousands of dollars in outstanding wages.
A lack of fuel had also left the vessel without lighting, air-conditioning or power for refrigerators as authorities delivered urgent food and fuel supplies to the crew.
In recent weeks the vessel sailed to Brisbane, and the International Transport Workers' Federation says the Maryam was now sailing to Vietnam to undertake urgent repairs following the replacement of the remaining crew members.
"The situation facing seafarers onboard was absolutely appalling, with the 23 crew members critically short of food, water and fuel," ITF Australia co-ordinator Ian Bray said.
"The ITF found that many of the seafarers were working well past the expiry of their contracts, desperate to go home, and owed thousands of dollars in unpaid income.
Mr Bray said the state of the vessel was so bad its remaining anchor broke.
"The extremely poor state of maintenance was also highlighted when the vessel's one remaining anchor broke free, resulting in Australian authorities having the crew sail 50 nautical miles (90km) offshore to reduce the risk of an engine failure causing the vessel to run aground," he said.
The ban comes one month after a second bulk carrier owned by the same company, Aswan Shipping, was issued an 18-month ban for similar deficiencies.
Mr Bray said the ITF welcomed the record ban imposed against Aswan Shipping, but warned the significant abuses were becoming increasingly common in Australia's maritime supply chains.
He said Australia was one of the largest users of shipping for imports and exports worldwide.
"Unfortunately, the situation on these Aswan Shipping vessels is becoming increasingly common, with Australia's maritime supply chains increasingly reliant on flag-of-convenience vessels, registered in notorious tax havens and crewed by exploited workers paid as little as $2 per hour," he said.
"While the situation onboard the Maryam was particularly shocking -- resulting in the crew resigning and seeking support from Australian authorities to be repatriated home -- we are seeing a constant stream of similar cases in Australian ports."
He added that the Australian government needs to do more to crack down on such abuses, including allocating more resources to inspections and engaging in tougher enforcement of existing laws.