CLAIRE project

Short content

What: Measuring NO2
Where: Throughout the Netherlands
Sign up : No longer possible

General information

The CLAIRE project is a collaboration between RIVM and the Institute for Risk Assessment Sciences (IRAS) of Utrecht University. CLAIRE is the abbreviation for Comparison of Long-term AIR pollution Exposure assessment methods. Within the project we will investigate the quality of sensors, co-financed by the Health Institute (HEI). We are also examining whether the sensors in combination with calculations improve the air quality maps. In this project we want to hang the sensor boxes in many different places and we could use some help there. That is why we were looking for volunteers to adopt a sensor box for six months.

Selection of participants

The selection of the second round of 50 volunteers has been completed. The selected and non-selected received an email about this on April 19, 2022. This means that all volunteers for this project have been found.

Ultimately, 450 people came forward who were curious about the air quality in their garden or street and who wanted to measure this for 6 months. We were very happy with that, but unfortunately it also meant that we had to disappoint a lot of people. The first 50 volunteers were selected in April 2021 who lived in a beautiful location for this project. The second group of 50 volunteers was selected in the spring of 2022. The locations we selected were places where we expected a lot of nitrogen dioxide, but also where we expected little and also in between. The challenge was in making the right mix. The volunteers can view their measurements on the data portal and see the concentrations of particulate matter and nitrogen dioxide in their own environment.

Measurement campaign

Within the project, we measure at 100 different locations spread over a year. A sensor box remains in a location for six months and is then moved to the next volunteer to get a good opaque picture of the Netherlands. In addition, the locations were selected on the basis of, among other things, the distance from (major) roads, average NO2 concentrations and the contribution of the road to these concentrations was taken into account. For the two six-monthly measurement periods, RIVM tests whether the sensors (still) function properly.

sensor box

Different sensors are required for the measurements. To get a complete picture of the particulate matter concentration, we use two different sensors, namely the Nova Fitness SDS11 and the Sensirion SPS30 . The concentration of nitrogen dioxide is determined with the Alphasense B43F . The sensors are housed in a sensor box that has been specially developed for the project. The sensor box contains an intake opening and a fan to ensure good airflow. As soon as the sensor greenhouses are installed on site, the collected data is shared (real-time) on the data portal .

Role of RIVM

Within the project we do not only use the measurements by the sensor boxes. We also use the official station measurements as shown on Luchtmeetnet and the model results. We combine these data to see whether we can estimate the particulate matter and nitrogen concentrations. Together with the IRAS, we will then compare this estimate within the project with other methods to determine the concentrations. We will keep you informed of the results.