The Government has offered assurances that police will be ready and able to help businesses enforce vaccine pass use, saying officers "know what's coming".
Vaccine certificates - called My Vaccine Pass - went live this morning, and Prime Minister Jacinda Ardern announced this afternoon the traffic light system would take effect nationwide shortly after the 29 November Cabinet meeting.
The Auckland regional boundary would also be lowered for vaccinated or tested people about two weeks later, on 15 December.
With the traffic light system - also called the Covid Protection Framework - promising to allow businesses to open to the vaccinated even under the highest restriction settings, businesses say there are still some grey areas to work through.
Retail NZ chief executive Greg Harford on Wednesday told Morning Report they had concerns about staff being able to police the rules, and whether all staff would need to be vaccinated also.
"It is going to be a little bit problematic for those businesses that might need to put extra staff on the door, for example, particularly if you're a cafe ... you've got less income coming in and then additional costs to have someone on the door. We really need to work that kind of thing through."
He said the idea of staff having to police the vaccine pass use was a big worry.
"We're seeing a big upsurge in, really, aggression and violence across the sector often prompted by some of the rules that are in place.
"We understand the need for some of these rules, what's important is that the obligation - the legal obligations - sit on the customer and that there's a really clear pathway for the police to become involved if people don't want to comply or become abusive."
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. Ardern says the idea of sole operators trying to check a vaccine certificate and serve customers is very difficult.
The story is different for hospitality, however. On the Orange setting - which regions with high vaccination rates would move to under the Protection Framework - bars and cafes can open without limits if using vaccination passes.
Under Red - which Auckland and regions with lower vaccination rates would move to - hospitality and events using vaccination certificates can have up to 100 people based on 1m distancing limits.
Hospitality businesses not using the passes are restricted to contactless businesses only under both Orange and Red.
COVID-19 Response Minister Chris Hipkins said businesses like bars were familiar with having to check customers' age.
He also gave assurances police could be called on to help, and the infringement regime which introduces greater fines and punishments for rule-breakers would provide some extra tools.
"Police of course are available to provide support around enforcement, and they've been involved in this process and the discussions around this process so they know what's coming and they will certainly be there."
Ardern said in some situations enforcement could be managed through reservations or contact with people "right up front to enable a more seamless process".
She later told Parliament that while those enforcing the rules could check photo ID against the name on the certificate, it would not be required for everyone over the age of 12 to carry such identification.
"It'll be up to those who are policing or enforcing to determine how they verify whether or not the individual is who they say they are. But this is no different than any of the enforcement activity that occurs at a bar or that occurs by police when they are stopping people on the side of the road, and, actually, this is a further enhancement on what some countries have been operating for quite some time."
On mandates for hospitality staff, Ardern said the government had provided "absolute clarity for hospitality or those areas where vaccine certificates were part of the framework and that they ... will be using them, they can require staff to be vaccinated."
"If you have a requirement for patrons to be vaccinated, it's not unreasonable to expect that then those working in that environment do as well."
She expected few hospitality businesses would not be using the vaccine pass.
"If you want to be open and you want to have as many customers as possible, you will have to be using vaccine certificates ... you do have some options but they are considerably constrained. I don't think many people will choose those."
The government would follow up with the hospitality sector to see if more could be done "to support those who are enforcing this," she said.
She said other sectors had plans for how the passes would be managed, with ticketed events for example looking at integrating the process into ticketing, and Hipkins said Air New Zealand had worked to ensure the systems would interface with their bookings.
Ardern said 91 percent of New Zealanders have had their first dose of the vaccine, so a large proportion of people was willing to get the vaccine, and many other countries had also used this kind of system.