As the government looks to pass 81 amendments in the lower house amid heated debate, the Australian Chamber of Commerce and Industry says it has been blindsided.

The changes, which passed the House of Representatives on Tuesday night, will close labour hire loopholes and add guardrails for the Fair Work Commission on minimum standards for gig workers.

The changes will also clarify the definition of casual workers.

But chamber of commerce chief executive Andrew McKellar said the amendments were being raced through parliament without proper consideration and would drive up costs for businesses.

“The government has failed to fix the fundamental issues in the bill,” he said.

“None of the government’s amendments deal with increased powers for union officials, road transport, the complexity of the labour hire changes or the extraordinary scope of the employee-like changes which go well beyond laws currently regulating gig companies.”

Business Council of Australia chief executive Bran Black said the amendments made a bad bill worse.

“We are deeply concerned the government is pursuing a policy which will make finding casual jobs harder in the middle of a cost-of-living crisis, when many Australians choose that extra pay,” he said.

“The changes to the definition of a casual employee are nothing more than tinkering at the edges and do nothing to fix the complex and confusing nature of the definition for workers or their employers.”

Workplace Minister Tony Burke said the changes would lead to better workplace protection and industry groups had been consulted.

“The amendments are pragmatic, practical changes that ensure we avoid unintended consequences,” Mr Burke said.

The minister said he was unconcerned by the attacks on the laws by business groups and negative advertising campaigns.

“The ads will misrepresent what the legislation does and at no point will they defend the loopholes that certain employers want to keep open,” he said.

“A lot of Australians seeing those ads would wonder why they don’t just spend that money on properly paying their workers.”

The workplace laws will also contain three Greens amendments, after the government decided to back a proposal which included treating super theft the same as wage theft.

ACTU secretary Sally McManus said the changes would crack down on workers being disadvantaged.

“Wage theft is a serious problem that successive governments have failed to act to address. Super theft compounds this, stealing from workers today and tomorrow,” she said.