Factsheet: Q&A: Air pollution in New Zealand towns

What does the LAWA Air Quality National Picture Summary 2021 tell us about air quality in NZ towns?

The LAWA Air Quality National Picture Summary 2021 presents an overview of air pollution levels, trends, and sources in New Zealand towns that are monitored by regional councils and unitary authorities. The Summary includes data from around 75 active monitoring sites measuring particulate matter (PM) or gas pollutants.

The Summary tells us that:

  • NZ has relatively good air quality, but in colder parts of the country many people are exposed to relatively high levels of PM in winter produced by wood and coal burning for home heating.
  • In these areas, the levels of PM can exceed air quality standards or guidelines, and this is usually associated with still winter days where there is no wind to disperse the PM in the air and, or for towns where an inversion layer traps air pollutants.
  • Last year, about 20 towns exceeded the guidelines for daily average PM10 concentrations.
  • Increased monitoring of smaller particles (PM2.5) reveals that PM2.5 exceeds international standards more often than PM10.
  • Most monitored sites are showing signs of improved air quality over the last 10-years or longer.

What causes air pollution exceedances in New Zealand towns?

In New Zealand, home wood burners are the primary source of air pollution in most towns during winter. Smoke levels are affected by what is burned and how, weather conditions, and the geography of the surrounding landscape. Other sources include outdoor burning, vehicles, industry, dust, and sea spray.

What are the health effects of breathing polluted air?

Breathing air that is polluted with coarse and fine particles is bad for human health, with the impacts ranging from respiratory illness to high blood pressure, and in the worst cases premature death.

When breathed in, PM10 can deposit in the upper airways and cause irritation, as well as affecting people’s lungs and heart. PM2.5 can lodge deep into our lungs and reach the bloodstream, potentially leading to respiratory diseases, heart attacks, lung cancer, and reduced life expectancy.

What are the different air quality indicators?

LAWA presents monitoring results where available for:

  • Particulate matter less than 10 micrometers across (PM10)
  • Particulate matter less than 2.5 micrometers across (PM2.5)
  • Gases including: Sulphur dioxide (SO2), carbon monoxide (CO), nitrogen diox-ide (NO2), ozone (O3) and benzene.

Not all air pollutants are measured and reported on in all monitored towns. Air quality monitoring is targeted at areas of poor air quality. The pollutants measured are determined by the sources of pollution.
Reporting on PM2.5 concentrations is not currently required, but councils are increasingly adding PM2.5 monitoring to gain more understanding about PM sources so that they can manage the problem. For more on types of air pollution see our factsheets covering particulate matter and gases.

Why do regional councils and unitary authorities monitor air quality?

Regional councils and unitary authorities measure outdoor air quality in their regions as part of their responsibilities for managing air quality. National Environmental Standards for Air Quality (NESAQ) are regulations that set limits in outdoor air for PM10, carbon monoxide, nitrogen dioxide, sulphur dioxide and ozone to provide a minimum level of health protection for all New Zealanders.

Regional councils and unitary authorities report on how levels of air pollutants in their towns compare to the NESAQ and to other international guidelines. Increasingly, councils are reporting on PM2.5 concentrations in line with the current World Health Organization (WHO) guidelines.

How do regional councils and unitary authorities monitor air quality?

Air quality monitoring stations are established where pollutant concentrations are expected to be highest and people are affected. Data are logged on site, sent to the relevant councils, and presented directly on LAWA. Learn more.

How do I navigate the LAWA Air Quality topic national picture map?

Best viewed on desktop, the national picture map presents a nationwide visualisation of air quality data available on LAWA. The data can be filtered by indicator and you can zoom in to further explore the results from your region at a glance. Click on a monitoring site dot to visit the monitoring station page.

How do I find out more about air quality in my region?

Click on the LAWA Air Quality topic ‘Region’ tab and select your region to learn about the main sources of air pollution locally and view air quality results and information for monitored towns under the ‘Towns’ tab. The monitoring site pages then include site specific context, history, and a range of data visualisations.

How can I help to improve air quality in my neighbourhood?

  • Use clean heating: Switch from your wood burner to a non-emitting home heating source if possible. Heatpumps, pellet burners, or ultra-low emission burners are better alternatives.
  • Burn smokefree: It’s important that if burning wood, the wood is dry, seasoned and non-treated. Get your fire going quickly, keep it burning hot, and don’t damp it down overnight.
  • Reduce outdoor burning: Refrain from burning waste outdoors (especially plastic, treated timber and toxic waste).
  • Reduce transport emissions: Choose to walk, cycle, or use public transport when possible. Service your car regularly to reduce exhaust fumes. Electric and hybrid cars don’t contribute the same emissions as petrol or diesel vehicles, so if you’re if in the position to switch they’re a great option.
  • Report pollution: If you see excessive air pollution that doesn’t look quite right, contact your regional council or unitary authority to report it. Many councils have processes for providing advice to the responsible party, and in serious cases may enforce regulations.

Why does the LAWA project make air quality data freely available?

The LAWA project aims to connect New Zealanders with the environment by making our environmental data open and accessible. By reporting air pollution levels from all long-term monitoring sites in New Zealand in one place, we can inform communities about their air quality, sources, and interventions so they can work together to achieve further improvements.