Businesses were given a few days’ notice to prepare for the lockdown and during this time, Syft’s Science and Applications Teams jumped into action upon the realization that the lockdown presented a unique opportunity to track the concentrations of VOCs in outdoor air throughout this period of tightly restricted economic activity.
Late on the eve of the lockdown, Dr Yadong Wang, Dr Kalib Bell and Dr Ian Farrell, along with some of our ever-helpful Production Engineers, Jozef Knottenbelt and Matt Lynn, got preparations underway to start taking direct, real-time measurements of VOCs in the outdoor air every 10 minutes with a Voice200ultra Selected Ion Flow Tube-Mass Spectrometer (SIFT-MS), until the country re-opened.
The Voice200ultra was housed at Syft’s headquarters, in an industrial area of Christchurch, and outdoor air samples were delivered to the instrument by a pump. The instrument was set up to operate unattended and continuously for 10 weeks, capturing the chemical signature of the city’s new rhythm. Wind speed has a significant influence on air pollution, so wind speed was also logged continuously based on the local weather data obtained from Weather Underground. The Voice200ultra is an inherently stable instrument and was made more so, by running an automated validation procedure, daily.
Because they had no idea what changes would occur, Yadong and Kalib set up the Voice200ultra to operate in an untargeted scan mode, recording data on all species produced from the air samples, over the mass range 15 to 200 m/z.
New Zealand remained at alert Level 4 from March 25th until April 27th when, in response to an improving situation, the alert level was reduced to Level 3, with a partial lifting of restrictions. Then on May 13th the alert level was reduced to Level 2. Finally, on June 8th the alert level was dropped to Level 1, removing all restrictions except border controls.
Throughout this extraordinary time, the Voice200ultra kept making continuous measurements six times an hour, recording the effect of the various stages of lockdown on VOC concentrations in the city’s air. Every day, Yadong would diligently connect remotely to the instrument from home, to check how it was getting on.