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Road Tunnel and Road Side Studies

air quality sample

NZTA commissioned GNS Science to monitor and collect air quality samples in a State Highway road tunnel. Traffic emissions were also studied at the Greater Wellington Regional Council air pollution monitoring station beside the Ngauranga motorway in Wellington.

Hourly APM samples were collected over 45 hours automatically using a “Streaker” sampler.

Vehicle combustion was the primary source of air particulate matter at this site, especially during periods of low wind speeds. Total PM10 levels averaged 25 micrograms/m3. However, when the wind is from the south-east (from the Wellington harbour), sea salt could also be a major contributor of PM10. Soil and sulphate had minor source contributions.

air pollution graph