Victoria's construction union will not support mandatory vaccines and says workers who don't want to be vaccinated due to "genuine concerns" should be respected.
The state government has launched a four-week enforcement and vaccine program for the building sector and warns it might lose its exemption to keep working during COVID-19 lockdowns.
Building sites account for about 13 per cent of the state's COVID-19 cases, with at least five new cases linked to building sites in Greenvale and Box Hill.
CFMEU state secretary for construction John Setka says the CFMEU is "pro-vaccine" but does not support mandatory workplace vaccination.
"I don't support anything being compulsory, people have genuine health concerns but I believe we should listen to the experts," he told ABC radio.
"There is some people with legitimate health concerns over being vaccinated and I think we've got to respect that."
Melbourne's construction workforce is currently capped at 25 per cent and Mr Setka said the union was enforcing "the gold standard" at building sites.
"We're trying to rotate people coming in and out, but we're suffering as an industry pretty badly at the moment," he told 3AW radio.
"We realise how important we are to the economy and it's very important for us to keep working."
Asked if the union would represent any workers stood down after declining to be vaccinated, he said: "We will take each case."
On Monday, Victorian Treasurer Tim Pallas said the building industry was at a "critical juncture" and with rising case numbers it could lose its authorised worker status.
"We'll do everything we can to ensure the construction industry can continue in a COVID-safe way," he said.
"The entire industry - employers, unions - are on notice. We've had significant transmission on building sites, and we simply cannot afford not to act if that continues to grow."
Construction workers will be able to get a jab without a booking at four major vaccination centres until September 26, and 20,000 priority Pfizer vaccines made available to these workers.
Australian Associated Press