Police confirmed on Friday morning it is 'highly unlikely' the man, who has not yet been identified, would have survived an underground rockfall.

PYBAR chief executive Brendan Rouse said the situation may have worsened, and they were assessing the scene remotely.

"It's not safe to put people anywhere near the hole at the moment," Mr Rouse said.

"Safety and welfare of all our people is the main priority.

"That's why it's being done remotely and that will form the basis of any other recovery plans going forward."

Australian Workers' Union national secretary Daniel Walton said it was extremely sad this operation was now transitioning to recovery, and the danger persisted.

"It is extremely hazardous still after the accident," he said.

"The company is still doing everything they can to truly assess the scene of the accident and to work out what the options are going forward.

"You can't do that and put further workers in jeopardy, you can't put mines rescue and police in jeopardy if you don't have a reasonable understanding of the conditions around the accident.

"It's our understanding we don't have that yet."

Mr Walton said the Tasmanian mining community had been through a lot.

"I don't think this will be an outcome that will be resolved in hours or days," Mr Walton said.

"I think it is going to be much longer than that."