Facing our fiery future: towards a community-based wildfire air quality monitoring network comprised of low cost sensors

A developing area of research for Carol Stewart, JCDR and School of Health Sciences, College of Health.

Increasing wildfire risk in Aotearoa New Zealand

Although New Zealand has not traditionally been considered a severely wildfire-prone country, it nonetheless has a significant history of wildfires (Guild and Dudfield, 2010) and the risk is likely to increase with climate change, as temperatures increase and droughts become more prolonged (Pearce, 2018; Huggins et al., 2020). Watt et al. (2019) estimate that numbers of ‘very high’ and ‘extreme’ fire danger days will increase by 71% between 2019 and 2040.

Two major events have occurred recently. The February 2019 Pigeon Valley fires in the Nelson/Tasman area affected mainly rural communities, but the February 2017 Port Hills fires, Canterbury, affected properties at the rural-urban interface (Squance et al. 2018; Langer et al., 2018). This fire destroyed nine homes and damaged five others; resulted in the evacuation of 1400 residents, caused the loss of one life, burned 1660 ha and had insured losses of NZD 17.7 million (Pearce, 2018). Pearce (2018) notes that there is an increasing worldwide trend of wildfires impinging on urban areas, with attendant risks to lives and property, and that in future, events such as the Port Hills fires may become the norm for New Zealand.

Port Hills fires, 15 February 2017. Image from Wikimedia Commons.

Health hazards of wildfire smoke: assessing exposure

There is increasing concern, both within Aotearoa and internationally, about the human health hazards of wildfire emissions, with exposure to wildfire smoke strongly associated with respiratory morbidity. However, a key challenge in providing appropriate and timely messaging to the public in downwind areas is the lack of data on ambient concentrations of smoke components, particularly PM2.5, which in turn inform exposure assessment and health-based messaging.

While routine air quality monitoring is a regional council function, for many regions of Aotearoa, monitoring stations are sparse to non-existent and do not necessarily provide relevant data for assessing health risks and issuing public health messaging for wildfires. We propose to develop an air quality sensor network that can be rapidly deployed in partnership with local communities and regional authorities in response to wildfire events. This data will supplement that available from any fixed monitoring stations and support public health messaging and potentially inform evacuation decisions.

Low-cost air quality sensor network research:

We recently received funding from the College of Humanities and Social Sciences minor equipment round to purchase two sets of commercially-available low cost but good quality particulate matter sensors (the BlueSky sensor, made by TSI, https://www.tsi.com/products/environmental-air-monitors/bluesky-air-quality-monitor/) and the Purple Air: https://www2.purpleair.com/products/purpleair-pa-ii-sd. These sensors are lightweight, portable instruments based on laser detection of particles, designed to measure four health-relevant airborne particle concentrations (PM10, PM4, PM2.5 and PM1 for the BlueSky and PM2.5 for the Purple Air). This equipment will be used to create flexible, self-configurable mesh networks. Rather than determining air quality form a collection of standalone sensors connected in a hub-spoke type network with centralised processing, the proposed self-configurable networks will be capable of tracking trends in smoke dispersion with a high level of spatial resolution and in real time.

This project strengthens links between Crisis Lab researchers and the College of Health, and offers opportunities to develop relationships with regional councils, schools and marae.

For further information contact Carol Stewart: [email protected]


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Squance, H., Johnston, D.M., Stewart, C., and Riley, C.B. (2018) An integrative review of the 2017 Port Hill fires’ impact on animals, their owners and first responders’ encounters with the human-animal interface.

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