When Can Low-Cost Sensors Be Used for LAQM?
Low-cost air quality sensors are increasingly being used for wide-spread and instantaneous measurement of air pollution. They are commonly deployed in research projects and there is growing use of them for the purposes of Local Air Quality Management (LAQM).
While low-cost sensors are a useful measurement tool, their data quality limitations mean they are only suitable as indicative monitoring for LAQM purposes, assuming appropriate QA/QC has taken place. They are not currently accepted as a primary method for statutory LAQM reporting and therefore they cannot be used to formally assess compliance with air quality objectives.
Applicable use for low-cost sensors for LAQM includes:
- Screening for potential hotspots or traffic-related sites before deploying more accurate monitoring.
- Identifying spatial variation in pollutant levels, especially where local concerns exist.
- Community engagement and citizen science – assisting in raising awareness of general air pollution levels.
- Complementing other monitoring methods such as diffusion tubes or continuous automatic monitors for better spatial or temporal coverage.
Due to the indicative nature of low-cost sensors, it is also not advised that they are used for monitoring support in Detailed Assessments (i.e. for model verification purposes or stand-alone monitoring evidence for compliance) or as evidence to revoke or declare an AQMA without additional validation against a reference monitor.
For further information on the use of low-cost sensors please refer to PAS 4023 – Low Cost Air Quality Sensor Systems in Outdoor Ambient Air. This report provides recommendations and advice on selecting, deploying and controlling the quality of air quality sensor systems in outdoor ambient air. It covers the following:
- How to select and use low-cost sensor monitoring systems
- How to undertake quality assurance processes and generate more reliable data from these systems
- Provides examples of monitoring scenarios and network calibrations
More information can also be found in FAQ140 ‘How Suitable are ‘Low Cost’ Sensor Systems for LAQM monitoring?’ , which also contains advice from the Air Quality Expert Group (AQEG) on low-cost sensor use.
