Five protestors were arrested after bringing Adani Australia's Abbot Point port to a halt late last week to protest to the company's Carmichael coal project.

The activists, including a 74-year-old ex-serviceman from Cairns and 22-year-old student Tess Newport from Melbourne, locked themselves to equipment which port operations CEO Dwayne Freeman described as a foolish decision.

"These people, who have no experience, knowledge or understanding of the operations involved with a heavy industrial site like ours are extremely fortunate to not have been seriously injured or killed," he said in a statement.

"Such dire consequences were only avoided due to the diligence of our operational staff, who were inspecting the plant and became aware that the protestors had locked on to a live and operational automated conveyor system.

"We respect the right to protest, but based on the negligence and violence of the protests we are now seeing, it is unfortunately highly probable that one day, actions such as this will end in a fatality - which is unequivocally unnecessary."

Newport said she had seen the mining industry rip off workers, communities and the environment in Victoria, adding "We don't want jobs in a dying industry - we need jobs for the future."

The Carmichael project has been a source of controversy over feared environmental damage and the company seeking up to A$1 billion (US$0.79 billion) in a federal concessional loan for a railway line to link the mine to the port.