The country is in COVID-19 Alert Level 4. You have checked out MBIE’s regularly updated COVID-19 essential services list and found out that you can operate. However, before you usher essential service employees back to work, you need to ensure that the workplace meets the stringent requirements the government has put in place around health and safety in the workplace.
The Health and Safety at Work Act 2015 (HSWA) requires all employers to take practical steps to mitigate risk and protect workers from workplace hazards at all times. Any infectious disease encountered in the workplace is considered a workplace hazard. WorkSafe has expressed zero tolerance for anyone using COVID-19 as an excuse to endanger workers or indeed the public through less-than-thorough attention to health and safety. You must operate in a way that eliminates or minimises the risk of COVID-19 transmission as far as is reasonably practicable.
The above list is not exhaustive. You are obligated to assess the unique risks of your workplace and be responsive to risks as they arise.