Business groups say a union's proposal to have guarantees of earthquake building safety written into collective employment contracts is a step too far.
New Zealand's biggest union, the EPMU, is looking at whether to demand that employers prove their buildings meet the earthquake code and strengthen them if they do not. Delegates will vote on the proposal in July.
Wellington City Council has been assessing large numbers of buildings according to earthquake vulnerability and some have been red-stickered or abandoned by their occupants, including the Accident Compensation Corporation and Inland Revenue.
But the Engineering, Printing and Manufacturing Union fears other people throughout New Zealand are still in danger. It says the devastating Canterbury quakes and Pike River tragedy on the West Coast have revealed just how unsafe some workplaces are and employers must take steps to make sure buildings are safe.
However David Lowe, of the Employers and Manufacturers Association, says current health and safety laws already give robust protection and there is no need for a legal battle.
"Most people don't run off to their lawyers and run off to the employment agreements. What they do is they sit down and say, 'We've got a terrible problem here' and they sort it out. We've seen employers and workers sit down and sort out all sorts of issues before."
EPMU national secretary Bill Newson said people have the right to a safe workplace and the union is not ruling out striking if necessary.
"We're not all about to walk off the job and declare World War III over this issue. But certainly if employers haven't done the assessment, won't do the assessment - then we're going to have to make it the subject of a formal claim in bargaining."
An employment lawyer believes the move would meet with enormous resistance from employers, who would be wary of signing the contracts because it could put them at risk of being sued.
Susan Hornsby-Geluk says it would be a huge obligation on employers to fully comply with the earthquake code overnight.
The Property Council, which represents property owners and developers, says now is not the time to make any sort of deals regarding safety because of uncertainty about building standards.
Chief executive Connal Townsend says those standards could well change once the Royal Commission finishes its inquiry into the Canterbury earthquakes.
Mr Townsend says the commission will make recommendations to the Government, which may then alter the building code.