Huimin Lin carrying pollution monitoring equipment

Auckland University student Huimin Lin carrying a “PTrak” particle counter in her left hand, a “Langan” carbon monoxide sensor on her belt, a noise meter pinned to her cardy, and a GPS receiver in her belt. She is shown walking on a specified route in Queen Street. She took this route (Wyndham Street to Wellesley Street and back) every 15 minutes during rush hour, whilst others, similarly equipped, walked other specified routes. She used the notebook to note down her timings, and anything that might impact the measurements – sources of loud noise, dirty vehicles, etc. [Credit: Ian Longley]