The bitter and long-running public sector wages dispute took a new turn on Thursday afternoon.

Mr Ferguson said the secretary of the Department of Health would write to employees to "inform them of the potentially serious impacts of these actions and remind them of their duties".

"Where duties aren’t performed, industrial measures including pay reductions and stand-downs will be pursued," Mr Ferguson said.

"The Department of Health has advised that if the bans announced by HACSU bosses proceed, critical services will cease and there will be serious impacts on patients and attendant public health risks.

"This action is deliberately targeted at compromising patient safety and HACSU bosses need to take responsibility for the outcomes.

"The actions by HACSU bosses will have a direct impact on infection control and cleanliness in hospitals, endangering patients, visitors, staff and other health professionals."

Health and Community Services Union assistant secretary Robbie Moore said members would continue their bans which include not cleaning public hospital toilets every day.

"This is a very hostile move," Mr Moore said.

"It is absolutely shocking when these workers are working in a system that is in crisis.

"The Health Minister's action is unprecedented and shows he has no idea of what he's doing.

"The members are not backing down and this will just make them angrier and will backfire on the government.

"You touch one worker, you touch them all."

Mr Moore said members would consider their options and if anyone was stood down or had their wages cut it was possible the matter could be taken to the Industrial Commission.

Mr Ferguson renewed his call for HACSU members to "immediately call off these dangerous actions".