Unions and a mining company have gone head to head at a Government committee over how to best deal with improving health and safety after the Pike River tragedy.

Parliament's Transport and Industrial Relations Committee has been hearing submissions on the bill to improve health and safety in the mining sector.

The legislation comes from recommendations by the Royal Commission into the Pike River coal mine tragedy, which killed 29 workers.

The legislation would establish a stand-alone Crown agency, WorkSafe New Zealand, governed by a board of up to nine people and would reintroduce health and safety representatives in mines.

Gold mining company OceanaGold told the transport and industrial relations committee that part of the legislation to improve mine workplace health and safety after the Pike River tragedy should not apply to mines that are above ground and are not coal mines.

OceanaGold general manager Bernard O'Leary said the commission recommended check inspectors for underground coal mines.

Proposed legislation had suggested the inspectors should be placed in mines across the mining and quarrying industry.

Mr O'Leary said it was disruptive that health and safety representatives would be able to give notice of suspension of mining operations when there is a risk of serious harm.

The representatives could also call an immediate stop if the risk of harm was immediate.

"It's a pretty powerful part of the act and quite frankly a scary proposition in the hands of an ill-informed or maybe overly-eager representative."

Labour Party labour spokeswoman Darien Fenton provided a letter from OceanaGold's EPMU Delegate Wendy Mitchell saying all EPMU delegates at the company's mines supported the reintroduction of mine inspectors.

"We are an open-cast mine dealing with hard rock but see no difference to the issues that can occur in underground soft rock mines.

"Companies can start out as open-cast and then go underground. Would these companies slip through the radar as they would already have all their systems in place in line with being an open-cast mine?" she said in a letter.

Ms Fenton said the bill needed to make specific reference to workers, and they needed to be included on any governance board.

Green Party MP from the West Coast, Kevin Hague, said the Government were taking recommendations from the Royal Commission and employing them in the "palest and least effective way imaginable".

Head of the Council of Trade Unions Helen Kelly told the committee it was important to remember that a lack of health and safety at Pike River mine was why the members and submitters were at the committee today.

"I think it's ironic that we're sitting here arguing about the level of power of workers in mines - given what happened at Pike River.

"I do want to point out that it was workers that were killed in Pike River - and it wasn't because of them, or their union that there was insufficient health and safety in that mine.

"If somebody had stopped work at Pike River, in amongst all those concerns, we might not be sitting here," she said.

Ms Kelly said there should be a tripartite board, similar to the Safe Work Australia Act.

It would involve up to 10 members including at least two representatives each from the most representative organisation of workers and the most representative organisation of employers in New Zealand, Ms Kelly said.

- APNZ