Scientists are measuring the air quality along Queen Street in Auckland, to find out how much car, truck and bus emissions contribute to air pollution in the centre of the city.
NIWA Air Quality head Guy Coulson said the study will use two stationary monitors and portable devices to analyse air quality in different areas and at different heights.
He said that could help town planners understand if the transport routes need to be changed to protect people's health.
Dr Coulson said the detailed study should show how pollution flows through urban canyons, such as High Street.
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