Officer recalls CFMEU intimidation

A police officer says he was intimidated by a union organiser after being called to a Canberra worksite where the CFMEU was stopping a concrete pour.

Detective Sergeant Mark Battye told the royal commission on Tuesday that John Lomax swiped an entry permit card close to his face and then tried to "snatch" it out of his hand in December 2012.

Builder Darrell Leemhuis had told another hearing about how three union officials, including Mr Lomax, entered his Fyshwick site and blocked a concrete truck from pouring its load.

The concrete had to be dumped elsewhere, costing thousands of dollars.

The officer denied he approached Mr Lomax when he arrived on the site, instead saying the union organiser came into his personal space, which he defined as within a metre-and-a-half.

"I was concerned that if he was trying to intimidate police, I could only imagine he would probably use (greater) intimidation of any people on the site," Detective Sergeant Battye told the commission.

But he categorically denied he told Mr Lomax his name was familiar or that Mr Lomax had relatives that caused trouble.

The union's lawyer John Agius put it to the officer that he had made up a lot of his evidence.

"Definitely not," Detective Sergeant Battye said.

The commission also heard on Tuesday from a commercial builder who conceded there were safety issues on one of his Canberra worksites.

Samuel De Lorenzo was shown photographs depicting a worker standing on a milk crate and electrical cords running along the ground.

He admitted to Mr Agius they posed safety concerns, which were fixed within an hour of ACT branch secretary Dean Hall leaving his site in June 2014.

Mr De Lorenzo told the commission earlier that day a group of officials had tried to enter the site telling him he needed to observe a lockdown day.

"I'm pretty sure if we'd had the opportunity to walk around that day without having eight people shouting at our gate, we would have been able to rectify all of those things," he said.

The builder, who had been in the industry 40 years, said hazards could always be found on a site but it was about managing risks.

His company maintained its sites to the best of its ability, he said.

The hearings resume on Wednesday.