It would depend on the specific advice from the Ministry of Health, but it is very unlikely close contacts would be able to not isolate.

CHASNZ have quite good guidance on this: https://www.chasnz.org/covid19

Good clear resources Chris :up: Looking through them, COVID-19 Contact Classification ProcessDo you know what to do if a Worker on-site becomes a COVID-19 contact? probably has has some pointers for Lucille

Our conclusion is that it is quite hard to tell - there has been a whole range of situations in businesses so far and it can be very hard to tell what will happen. The advice changes and the situation can be very different depending on a hundred and one different factors. You never quite know how Public Health are going to see things in terms of the greater risk. I think it also depends on the bigger picture in your geographical area too.

This is the current advice: https://www.health.govt.nz/our-work/diseases-and-conditions/covid-19-novel-coronavirus/covid-19-health-advice-public/contact-tracing-covid-19/guidance-workplaces-have-case-covid-19

This table has advice on how the different categories work for contact tracing https://www.health.govt.nz/our-work/diseases-and-conditions/covid-19-novel-coronavirus/covid-19-health-advice-public/contact-tracing-covid-19#typesofcontacts

In the Hawkes Bay last week a small business had to close while the workers isolated and were tested. https://www.nzherald.co.nz/hawkes-bay-today/news/covid-19-delta-outbreak-auto-repair-business-in-hastings-closed-for-10-days-after-staff-member-tests-positive/XPSTSGNOQMLG6PL4B4UASPH274/

The Ministry of Health has some good information too - https://www.health.govt.nz/our-work/diseases-and-conditions/covid-19-novel-coronavirus/covid-19-health-advice-public/contact-tracing-covid-19

It is still expected that close contacts isolate for 7 days (or 10 if unvaccinated). Vaccinated casual contacts are only required to monitor for symptoms. So the key is minimising the actual close contact as far as possible - even splitting the work areas into work groups and staggering breaks, etc can be the difference between close and casual in a lot of cases (remembering hygiene practices between break shifts - last one out of smoko cleans and sanitizes).

Here's some updated MoH Guidance:

https://www.health.govt.nz/system/files/documents/pages/contact_tracing-guidance-for-businesses-13dec21.pdf

Notably:

Where consistent mask use by the worker (the case) can be assured, this may lead to fewer people being classified as Close contacts.

And there are new definitions or a Casual Plus Contact:

Casual Plus contacts are people who had close range contact with a case (refer to box on the left), but
because of consistent use of other public health measures, such as masks, they are at a lower risk of getting COVID-19, especially if they are vaccinated.

Furthermore vaccinated Casual Plus Contacts:

Can continue to work. Self-monitor for symptoms for 10 days and if symptoms develop, no matter how mild, they should get a test and stay at home until a negative test result is received.

And there are new definitions or a Casual Plus Contact:

Casual Plus contacts are people who had close range contact with a case (refer to box on the left), but
because of consistent use of other public health measures, such as masks, they are at a lower risk of getting COVID-19, especially if they are vaccinated. — Chris Anderson

I know the excuse is that this is a "developing situation", but one of the main issues with how the NZ Goverment, Ministries and Goverment Agencies are managing Covid-19 is the complete inconsistencies with their approach and even terminology - especially problematic when it is within the same organisation. Case in point that the Ministry of Health has a completely different definition of "Casual Plus Contact" on the general contact tracing information page:

Casual Plus Contacts are unvaccinated people who have been in the same place at the same time, or near someone infectious with COVID-19. This will only be in some specific situations like at a school. — MoH

Similarly - why does the contact tracing guidelines for business not make even one reference to the QR Code system and Contact Tracing App, but does say that the business will have to provide an accurate record of all contacts through a excel worksheet - so if you have been diligently getting everyone coming onto your premises to scan your QR as the main method of keeping record then you in a bit of a tough spot and may be added to the list of "locations of interest" (with the weird threatening tone in the guidelines that this is a bad thing to happen).

No wonder NZ businesses (especially SMEs) are scratching their heads, confused as ever, and waiting for those that are running this show to actually figure it out for themselves.