NZ First 'looking very hard' at new health and safety legislation

New Zealand First leader Winston Peters says he will not vote for the government's health and safety reforms if there are not changes to the legislation, after earlier saying he was hamstrung by the coalition agreement.

Pike River campaigners Anna Osborne and Sonya Rockhouse are in Wellington, hoping to persuade politicians to reject legislation they say risks a workplace disaster.

The Health and Safety at Work Amendment Bill proposes a radical shake up of New Zealand's health and safety laws.

Speaking to RNZ's Checkpoint after meeting with Osborne and Rockhouse, Peters said he did not have confidence in the Bill as it stood.

Ahead of the meeting, he had said he would "fix it" after the election.

But he told RNZ he had since given an undertaking to Osborne and Rockhouse that if he was not satisfied with amendments to the legislation he would not vote for it.

He disagreed with the distinctions being made now about work site sizes, that "seem to us to be highly unsatisfactory and not fit for purpose".

Peters said he was going through the Bill "with a fine tooth comb" on the basis of only supporting legislation we can have "confidence in going forward".

He wanted to make sure they'd got the "appropriate rules", and with "great respect" to the Minister in charge Brooke van Velden.

"She's not worked underground, I have.

"So I've got a bit more better idea than some about what I'm talking about."

He did not want to see a repetition of the 1990s "mistakes".

The events that led to the Pike River tragedy were because of the lowering of safety standards, he said. He called Pike River a "corporate manslaughter site" where 29 people lost their lives.

"We have never taken our mind off that, and we are going to be looking very hard at this legislation, because frankly we are going to have to secure the safety of workers."

He called Pike River one of the worst events in the country's history, "because I saw so many political figures covering their butts, rather than being concerned about the 29 who lost their lives""

He said if the legislation was not changed, there would be an increased likelihood of another Pike River chapter in New Zealand history.

Peters said he would wait to see how things unfolded in the second reading of the legislation.

"It's premature to go too far at this point in time," he said, but he knew the outcome he wanted, "unless we get this outcome, we're not going to be supporting it".

Osborne said the government was weakening workplace protections she had worked hard to strengthen, and she hoped Peters would vote against it.

The bill - introduced by Workplace Relations and Safety Minister Brooke van Velden in February - would reverse many of the changes brought in by the 2015 Health and Safety at Work Act, which was passed in response to the Pike River tragedy.

Van Velden said on Tuesday that consultation with unions, businesses, and workers revealed they overwhelmingly felt the law was too complicated, and needed simplifying.

"It is not the case that we're going to see widespread accidents," she said.

"People want to do the right thing, they want to know what the right thing to do is, and we're here as a government to actually help them and clarify the law."

The Education and Workforce Select Committee has returned its final report on the bill, and it is now due for its second reading.

The Green and Labour parties opposed the bill.