NSW rail workers have been ordered by the Fair Work Commission to abandon their 24-hour strike on the NSW train network on Monday, as well as their indefinite ban on overtime from 6pm on Thursday.
Just before 1.30pm on Thursday, the commission's senior deputy president Jonathan Hamberger ruled that both forms of industrial action "threatens to endanger the welfare of part of the population".
They also threatened "to cause significant damage to the economy of Sydney - the largest and most economically important city in Australia", Mr Hamberger said.
The suspension of the strike and overtime ban will begin from 6pm on Thursday and last until 6pm on March 8.
The order is binding on NSW Trains, including the employees who are members of the Rail, Train and Bus Union, or members of the Association of Professional Engineers, Scientists and Managers Australia.
Mr Hamberger's order followed a five-hour hearing before the Fair Working Commission on Thursday, where separate applications by industrial relations minister Dominic Perrottet and Sydney Trains were heard concurrently.
Both parties were seeking suspension orders under s424 of the Fair Work Act, which prescribes that the Commission must suspend or terminate industrial action if it threatens "to endanger the life, the personal safety or health, or the welfare, of the population or of part of it," or if it threatens to "cause significant damage to the Australian economy or an important part of".
The hearing was presented with economic modelling prepared by NSW Treasury, which estimated the economic impact of industrial action would be between $50 million to $90 million.
Barrister Michael Easton, representing the minister, said the modelling supported the "inescapable" conclusion that "there will be significant economic damage cause by this ongoing industrial action."
"Your honour is compelled to act to make an order," he said.
Attempt to rebut this point, barrister for the RTBU Anthony Howell submitted that $90 million was a "miniscule" sum in the context of the $600 billion NSW economy.
RBTU state secretary Alex Claassens said he accepted the decision of the independent umpire.
"My members will be disappointed quite rightly but we have been able to make people listen to our concerns," he said.
"We were forced into this position by a Transport Minister who just wouldn't come to the table. We finally got him to the table [and] we are continuing to work through those issues."
However, he conceded that the Fair Work decision had weakened the unions' leverage in the negotiations, which were continuing with Sydney Trains management on Thursday afternoon.
"We will obviously stay here tonight and negotiate an agreement," he said.
The decision means the unions will have to take any in-principle agreement they reach to their members "the old fashioned way" of consulting them at rail depots over the coming weeks before they vote on deciding whether to accept the offer from Sydney Trains.
Sydney Trains chief executive Howard Collins said he would be talking to the unions to see whether they would waive the need for staff to be given two days notice of working outside their rostered hours in order to allow the rail operator to put on extra services on Thursday evening.
But he said the equivalent of a Saturday timetable remained at present and he urged people to plan their trips and avoid the peak between 5pm and 6.30pm if they could.
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