Michael Ravbar, a Queensland branch secretary for the Construction, Forestry, Mining and Energy Union said the Building Employees Redundancy Trust (BERT) fund provided redundancy benefits and training grants to its members.

When questioned on Wednesday about Brisbane workers claiming benefits after a protracted industrial dispute in 2012, Mr Ravbar, who is a director of the trustees of the BERT fund, said workers were entitled to claim hardship benefits because they had suffered financial pain after being out of work for four weeks.

Mr Ravbar said workers should not be penalised for a "dispute beyond their control and be starved back to work".

"It's their money and they are entitled to it," Mr Ravbar said.

Counsel assisting the royal commission, Jeremy Stoljar, challenged the claim, saying the money was held on trust by BERT.

Mr Ravbar replied: "If you play the corporate angle, but at the end of the day, it's their money. It's a workers' entitlement fund for redundancy purposes."

Commissioner Heydon then warned Mr Ravbar "that is rather a reckless thing for a director of a trustee to say".

"You have to accept don't you that what is paid out under a trust does depend on legalities, technicalities ... the terms of the trust deed," Commissioner Heydon said. "The members were not beneficiaries of a trust in an absolute sense, they were beneficiaries subject to the terms of the trust.

"I understand what you are saying about the suffering of people on strike who have no money and no strike pay, but [directors of] trustees do have to be careful."

Mr Ravbar conceded he "agreed with that". "It's been a very well governed fund," he said.

Mr Ravbar also told the royal commission hearing in Brisbane that he had been involved in discussions that led to two union delegates being appointed to a Hindmarsh construction project in Fortitude Valley.

He said workers were angry when an elderly hoist operator was ejected from his job and when one of the union delegates was pressured to leave the site. An extended industrial dispute erupted after workers were not paid for a day off work after their lunch room was flooded on March 28.

Evidence put by Mr Stoljar and Hindmarsh site manager Andrew Toms on Tuesday suggested the workers had refused to return to the site after the water was cleared and had not been paid for a strike day.

Mr Toms said the union had declared the site closed when it was in fact open.

Mr Ravbar also denied the CFMEU had blocked another company, Universal Cranes from entering work sites as part of allegations of widespread extortion.

Building workers who rallied outside the  Brisbane Magistrates Court on Wednesday in support of Mr Ravbar were threatened with fines.

Fair Work Building and Construction director Nigel Hadgkiss said building and construction industry workers who attended the rally during work hours without the permission of their employer could face penalties of up to $10,200. Employers or unions can also be fined up to $51,000 for involvement in paying or demanding strike pay.

“FWBC will not hesitate to bring people before the court where necessary,” he said.