Researcher Mobility Support
Application code: RMS-24-01-07
Guest working organisation: MIKES Metrology, VTT Technical Research Centre of Finland
Employing Organisation: Federal Institute of Metrology METAS, Switzerland
A survey of different calibration strategies for sensors and distributed sensor networks for air quality monitoring.
Air Quality Sensor Networks, particularly low-cost sensors, are increasingly used as an alternative to conventional monitoring methods, but they present significant metrological challenges regarding data quality and traceability. Mathematical tools, including machine learning algorithms, provide a solution for calibrating sensors and sensor networks.
This Research Mobility Support successfully combined the expertise of the Guestworking Organisation VTT Technical Research Centre of Finland in computational science, machine learning and mathematical tools with the METAS researcher´s specialized knowledge in the calibration of instruments and sensors monitoring trace gases and gas pollutants. This synergistic approach led to the development of effective, SI-traceable calibration methods for sensor networks.
Key Achievements:
- Optimized Algorithms: The research defined optimized machine learning algorithms and mathematical tools for calibrating air quality sensor networks.
- Guidelines will be elaborated on the calibration of sensor networks used in air quality applications with onsite calibration strategies to ensure the transfer of SI-traceability.
These guidelines can be applied by the selected user-cases of the EURAMET EPM FunSNM project (22DIT02).
Publications:
Some of the key findings of the activities were summarised in two joined papers.
- The main project outcome was summarised in a manuscript submitted by the end of the year 2025 to Aerosol and Air Quality Research Special Issue: Advancing Low-Cost Sensors for Air Quality Monitoring.
- A second manuscript on the mathematical tool will be submitted to IEEE Transactions on Instrumentation and Measurement. A Laplace-domain tool for in situ temperature calibration of sensors in a sensor network.
Outcomes were presented in the Atmosphere and Climate Competence Center (ACCC-FASN) Science Conference 2025 in Helsinki on 10-12 November 2025.
Although the research focuses on air quality applications, the findings of the project could be used by industrial stakeholders and in other applications, such as smart buildings, smart cities and heating districts among others.