UK cities regularly exceed air quality (AQ) compliance limits. On-going improvements in AQ will be offset by planned growth in some regions. More detailed observations during a period of quickly changing pollutant emissions would expand our understanding of the complex interactions between human activities, pollutant emissions and AQ control measures. A focus will be the differing responses of particulate matter (PM) and gaseous pollutants. The COVID-19 period provides an unprecedented opportunity for additional measurement to illuminate factors which influencing UK air quality and health. Cranfield University (CU) is a controlled mixed (urban and rural) site in the ARCs heart. It has a self- contained campus with a unique combination of infrastructure, site types and facilities. The Cranfield Urban Observatory reference station is operating, and multi-species sensor units are available for immediate use. In this project, these units would be deployed as soon as possible at identified sites across the Oxford-Milton Keynes-Cambridge Arc (ARC) in order to provide a detailed observational record during a period of low traffic and industrial activity while COVID-19 restrictions are in place and being eased. Real-time information can be provided on the interaction between air quality and the easing of social distancing measures. These measurements made during a period of known intervention measures will inform infrastructure planning for the ARC and the design of Low Emission Zones and air quality policy more generally. The data will be available for use by researchers looking at before/during/after effects of these measures.