The government is releasing a new tool to help businesses assess whether they should be requiring workers to be vaccinated.

Workplace Relations and Safety Minister Michael Wood is giving further details.

The assessment tool will be available from mid-December.

Meanwhile, workers covered by the My Vaccine Pass mandate will need to have their first dose by 3 December and be fully vaccinated by January 17.

"As we move into the new framework, many people have been seeking greater certainty about workplace vaccination requirements," says Wood..

"That's why a few weeks ago I announced that we would introduce a clearer and simplified risk assessment process for employers to follow when deciding whether they can require vaccination for different kinds of work."

He says the tool provides a clear legal framework to help businesses and other employers to decide about vaccinations in the workplace.

It builds on guidance and advice from workSafe, public health agencies, Business New Zealand and the Council of Trade Unions.

It has four criteria, at least three of which must be met before a business can require vaccination:

-How large is the space people work in

-How close people are to others

-How long they are near to others

-Whether they provide services to people vulnerable to Covid-19

Wood says the new process will not override risk assessments already done under existing guidelines, and all health and safety risk assessments will remain valid.

Legislation allowing the tool to be created and setting up a four-week minimum paid period of termination, as well as time off to get vaccinated, will be passed this week, he says.

"We've tested this with stakeholders and it's received broad support, including from religious communities."

This applies to hospitality, events, gatherings, close contact businesses and gyms.

When announcing the traffic light system will begin from 11.59pm on 2 December, Prime Minister Jacinda Ardern said the government will provide extra guidance for businesses to prepare, and release an assessment toolkit for firms wanting to require staff to be vaccinated.

The app for businesses that require proof of the vaccine pass for entry will be launched today.

Ardern also announced after Cabinet yesterday that hairdressers and barbers in Auckland will be able to reopen when using the passes, in part to trial the system, from Thursday.

Hospitality businesses have also been hoping for some clarification over enforcing the vaccine pass for entry requirement, and on whether all staff would need to be vaccinated.

The government last week said police had been involved in the planning for this and would be available if customers became unruly.

For retail, the vaccine passes are essentially opt-in - with no difference between those using them and those not - and restrictions including 1m distancing under Orange and Red.