March 2013

Sensors measures air quality quicker and at lower cost

Soon, thirty strategically selected locations in Eindhoven will have boxes sized 36 by 20 by 15 centimetres. Every few minutes, these boxes will send information on the air quality to a central database. At the heart of the boxes are two sensors developed by ECN.

NO2 and particle sensor

Together, these data will provide the basis for a real-time map of the air quality above the largest city in the Brabant region. One sensor in the box measures the concentration of nitrogen dioxide, which is emitted by sources such as traffic and industrial activities. The other sensor maps the volume and size of the particles floating in the air. Once all data have been collected in the central database, ECN software will process the data.

From measuring mast to sensor

ECN has many years of experience in the measuring of air quality. High-level technological and large-scale measuring equipment maps the concentration, size and chemical composition of gases and substances in the air. Several years ago, ECN started to develop smaller-scale, low-cost equipment. Meanwhile, an optical particle sensor has been developed, which conducts online measurements to establish how many particles the air contains, distinguishing various categories of sizes ranging from half a micrometre to ten micrometres. The nitrogen dioxide sensor is currently being further developed.

More and rapid measuring

Sensors are much cheaper than the equipment used up to now. More measuring points can now be realised at a lower budget. This way a wider spatial coverage is realised. On top of this, the sensors are sending their measurements almost continuously, thus allowing for a nearly real-time resolution. The Aireas system, which is based on these sensors, offers Eindhoven a good picture of the influence of traffic, weather conditions and local conditions on air quality in the city.


The Aireas project is a collaboration project of ECN, the municipality of Eindhoven, the province of Noord-Brabant, Utrecht University and Philips. Aireas offers insight in health conditions in the city, the influence of traffic flows and the resulting environmental burden. The project in Eindhoven serves as blueprint for follow-up projects at other locations.

Read more about the Aireas project.

Please contact Gerard de Groot if you wish to discuss the opportunities for measuring air quality with ECN technology. Give him a call at +31 224 564666.