People are becoming increasingly aware that good air quality also guarantees a better quality of life. Correctly measuring this air quality is therefore crucial for implementing suitable measures. In its Sensor Testing and Validation Centre, VITO studies the quality of small, cheap sensors and develops calibration models to make the results of the measurements from these sensors even more reliable.

Regardless of whether we are outside or indoors, the quality of the air we breathe affects our health. For measuring this air quality, the use of traditional high-tech instruments yields very reliable data.  But because of their cost price, only a limited number of these measuring instruments can be used and they only provide a picture of the air quality in a limited number of locations. As air quality is highly variable, we have to look for smaller, cheaper but sufficiently reliable sensors that can be used on a large scale.

The quality of the sensors currently available is not always as good as it should be. We also lack a clear European legal quality framework. Europe has imposed limit values and quality requirements for outdoor air quality, and the measuring methods have to comply with these. The Flanders Environment Agency (Vlaamse MilieuMaatschappij – VMM) measures the air quality to assess whether we meet these limit values in Flanders. The key question for the development and also the evaluation of these small sensors is what they can measure exactly and how accurately. After all, when mapping out the quality of the air, you can prioritise several different parameters. Which polluting substances should they detect?  Do users want to know absolute concentrations or rather trends or relative differences?
VITO has the necessary infrastructure to compare the performance of sensors with reference instrumentation, both under controlled laboratory conditions and practical field conditions.

VITO’s Sensor Testing and Validation Centre studies the quality of the sensors and establishes whether they measure exactly what they promise and whether the results of these measurements are reliable. VITO studies this for sensor manufacturers, but also for companies and governments that use sensors and want a guarantee that the sensors they have installed are effective. VITO also supports governments through the development of a standardised test protocol for testing sensors that are used in all kinds of applications. VITO is currently testing a sensor network together with Imec and the VMM in Antwerp, in order to determine whether these sensors might have a significant impact on metropolitan policy.  In view of that policy support, VITO also focuses on the choice of the appropriate measurement strategy, intelligent data processing and analysis, data visualization and ultimately the translation into possible measures.

Sensors can also make a difference on a smaller scale. In 2018, for example, VITO developed an Indoor sensor box, an aesthetically pleasing instrument that immediately provides a clear visual indication of the air quality in locations where vulnerable people gather, such as schools, hospitals, nursing homes or childcare centres. The colour of the box indicates whether action should be taken, e.g. when a window urgently needs to be opened for ventilation.