But Union ACT has labelled the move a "stunt" to stop ads which were rolled out on radio stations 2CC Canberra and Canberra FM104.7 last week.

Master Builders ACT executive director Kirk Coningham said the advertising campaign directly targeted the ACT's residential construction and renovation teams.

He indicated the organisation would launch legal action over the radio advertisements in the ACT Supreme Court this week.

The statement did not make clear on what grounds it would attempt to challenge the campaign in court.

In the statement, Mr Coningham refuted some of the figures put forward in the advertisements, including that the industry fielded 43 serious claims from workers a month.

"The accepted figure from Safe Work Australia, for the entire industry including commercial, civil, landscaping, plumbing and electrical, is 19," Mr Coningham said.

"The territory's residential sector records 1.6 serious claims a month.

"Master Builders represents about a third of these, so the real number for Master Builders is closer to one serious claim every two months. That's still unacceptable, but it's a far cry from 43 a month."

But Unions ACT secretary Alex White said the territory remained the least safe jurisdiction in Australia for construction workers.

"The Master Builders Association would better serve the community by working with unions to ensure their members stop injuring construction workers.

"This stunt by Mr Coningham is another indicator that the MBA has sadly abandoned its role as a sensible stakeholder committed to improving safety."

Mr Coningham claimed the radio ad was the latest part of a sustained union campaign attacking Canberra's "non-compliant" construction workers.

"The territory's construction teams have refused the new three-year union agreement. Only one local company has signed the union deal while over 20 teams, including two more last week, have voted it down.

"The union is hopping mad and going to increasingly extraordinary lengths to punish non-compliant workers."