Concentrations of PM10 (pollution particles less than 10 microns in diameter) are high at times during winter in Christchurch, Timaru, Ashburton, Rangiora, Kaiapoi, Geraldine and Waimate. This type of pollution, mainly caused by inefficient solid fuel burners and open fires, causes serious health problems for thousands of people.
Other air quality issues
The other main air quality issues in Canterbury are:
Air pollution from transport
In Christchurch, vehicles are not a major cause of air pollution. However, along busy roads such as Riccarton Road, air pollution may be high at times. Poorly tuned vehicles can also create smoke (and sometimes odour) nuisance.
Air pollution from commercial activities
In Christchurch as a whole, industry is not a major source of air pollution although in industrial areas, air pollution from commercial sources may be high at times. Some commercial activities create odour as well as smoke.
Air pollution from agrichemical spraydrift
Large-scale agrichemical spraying generally only occurs periodically in rural areas. It then presents a short-term localised source of air pollution. Best practice limits the risk of humans or animals being exposed to potentially harmful chemicals.
Air pollution from odours
Odour is one of the most frequently raised concerns regarding poor air quality in Canterbury. Odour, possibly more than any other form of pollution, directly affects the "amenity values" of an area. Amenity values are those qualities and characteristics that contribute to people's appreciation of an area.
Air pollution from other air pollutants
Apart from suspended particulate (PM10), Environment Canterbury monitors the following other air pollutants: carbon monoxide, nitrogen dioxide, sulphur dioxide, hazardous air pollutants such as benzene, and ozone.