Major employer association the Australian Industry Group found more than half backed some form of mandating.

About 24 per cent said they would like to mandate vaccinations for some or all of their employees and 27 per cent wanted a health order to decide.

A further 37 per cent plan to offer and encourage vaccines while the remaining 10 per cent were unsure or felt it didn't apply to their workplaces.

Ai Group chief executive Innes Willox said it was clear some businesses would closely watch others imposing mandates on staff.

"The group that favours health orders being in place no doubt would prefer the legal certainty that comes with such orders," he said.

"However, governments do not appear to favour any significant expansion of the small number of such health orders now in place."

Mr Willox said despite the "red herring" that health orders were the only way to mandate vaccines, employers would use long-standing legal rights where lawful and reasonable.

"Employers will initially look at the issue from the perspective of how they can protect their staff and their customers," he said.

"As more businesses mandate vaccination, the question will shift to whether they will need to mandate vaccination for their own staff who visit businesses that have a mandate in place."

The Fair Work Ombudsman has updated its advice on mandatory vaccines, setting out what is likely to be reasonable under existing law.

But the federal government continues to resist pressure from business groups to provide more clarity through legislation or regulation.

Australian Associated Press