Summary

In 2020, the New Zealand Government introduced a four-tiered Alert Level system to help combat the spread of SARS-CoV-2, the virus that causes COVID-19. An unforeseen outcome of the extended restrictions in Auckland was that significant reductions in both daily and annual concentrations of two key pollutants, nitrogen dioxide (NO2) and particulate matter less than 2.5 micrometres in diameter (PM2.5), were observed. Research in this area has gone on to demonstrate the health benefits that may accrue from reductions in air pollution due to a reduction in vehicle movement, because of COVID-19 restrictions.