A parliamentary hearing has been told unions in Queensland are abusing right-of-entry provisions.

The commercial building industry has warned union interference could soon plague the residential sector if health and safety laws aren’t overhauled.

Attorney-General Jarrod Bleijie’s proposed reforms will force unions to provide at least 24 hours’ written notice before entering a work site.

Internal health and safety representatives, elected by colleagues, will also lose the right to direct workers to stop work over safety concerns.

Mr Bleijie says the laws will stop unions shutting down workplaces by using the excuse that there have been safety breaches when they are really pushing industrial agendas.

But unions fear the changes will lead to more deaths and injuries.

A public hearing was held in parliament on Wednesday, where employer groups supported the reforms.

Housing Industry Association executive director Warwick Temby said unwarranted union interference had led to more disputes, decreases in productivity, and declines in profitability.

The hearing was told about one case in which a broken temporary toilet led to a seven-storey construction site being locked down for three days.

“Should such misuse of entry provisions shift to the residential sector, it is likely there will be detrimental effects on small and medium businesses,” Mr Temby said.

John Crittall, of Master Builders, said the changes would require employers to “step up” in terms of how they managed critical incidents, such as a crane dropping its load.

“They already have those plans now, but they will have to revisit them and realise that they do have obligations to manage critical incidents without any union involvement for at least 24 hours,” he said.

There were nearly 10,000 safety breach complaints to the Department of Justice and Attorney-General in 2011/12 and 2012/13. Just 57 of those regarded right of entry.

Queensland Council of Unions (QCU) president John Battams told the hearing the reforms were not based on any real evidence and were designed to limit the influence of unions.

“It is a proposal to handcuff the two people (unions and health and safety representatives) who make a difference,” he said.

“Any independent observer would say that the removal of those two representatives would see health and safety conditions decline.

“The vast majority of employers want to do the right thing, but others will want to cut corners to save costs at the expense of their workers.”

The QCU says if the changes are implemented, it will monitor any increase in deaths, illnesses and injuries and will hold the government accountable.