High Pollution Nights
Maximum high pollution nights allowed per year
High pollution nights are reported for each calendar year. Maximum allowable high pollution nights per airshed are determined by the NESAQ. From 2021 the target for each airshed will become one or fewer high pollution events per calendar year.
*Geraldine exceedance exemption: The Ministry for the Environment has granted an exemption for the PM10 exceedance in the Geraldine airshed on 1 February 2019 as it was an exceptional circumstance. Although it will still show in our data as an exceedance, it will not count towards total PM10 breaches in the Geraldine airshed for 2019.
The state of our air
Air quality is improving in the Canterbury towns and cities we monitor; however, pollution levels still sometimes exceed national health-based environmental standards. We have developed tools that enable you to check air quality in eight areas, known as airsheds, where we are focusing our efforts. View the latest air quality environmental snapshot report.
Improving air quality
Despite a reduction in the number of high pollution nights recorded across Canterbury in the past decade, we still need to do more to make significant improvements to our air quality. Our air plan will help us meet national standards in coming years. Homeowners, industry, large businesses and landowners all have a role to play.
A major challenge is to have clean air and warm homes — are you up for it?
The science behind our air quality
The air quality standard we exceed most often relates to PM10, which is particulate matter 10 micrometres or less in diameter. PM10 is made up of things like smoke from home heating, industry and vehicles, as well as dust and sea salt. In Canterbury, PM10 levels generally peak in winter. Air quality investigations help us determine where we have air quality issues and what we need to do to manage them. Our technical staff analyse air quality data and trends to identify sources of air pollution and the relative significance of various contaminants.