The Use of Low-Cost Air Quality Sensors and Sensor Networks for Understanding Air Pollutant Levels and Human Health Impacts

With an annual UK impact equivalent to around 30,000 deaths, air pollution is a pressing area of research. This project utilises low-cost portable sensor networks to record air quality data at a spatial and temporal resolution far beyond that of existing reference instruments. Most notably, the ongoing Breathe London study, with 100 sensors across the city, will be analysed and provide insight into the impact of major policy decisions, such as the Covid-19 lockdown and introduction of the Ultra-Low Emission Zone (ULEZ). Significantly, this data set includes measurements of CO2 enabling calculation of emission indices to correct for the effects of extrinsic factors such as metrology on pollutant levels. Important challenges remain to refine the sensor calibration protocol and correct for data artifacts, and learnings from this study will be applicable to future implementations of the sensor network.

Alongside large-scale outdoor data collection, comparable technologies can offer more individualised exposure data. Personal air quality monitors record an individual's everyday exposure to pollution, alongside data relating to their location and activity levels. This information leads to a more accurate estimate of individual dose in different sections of the population. Elsewhere, indoor ventilation can be assessed through sensor measurements of levels of CO2 and particulate matter (PM), and addresses a critical question during the current Covid-19 pandemic.