The World’s Dens­est Air Quality Measure­ment System

Helsinki Air Quality Test Bed

A dense air quality measurement system – the first of its kind in the world – that supplements the existing network was built in the Helsinki metropolitan area. The accurate measurement system helps improve air quality and create new business that is climate-friendly and environmentally friendly.


A comprehensive air quality measurement network enables more efficient management of particulate emissions and improvement of air quality.

90% of European city residents are exposed to excess concentrations of pollutants. Globally, approximately seven million people are killed by air pollution annually.

What is it all about

Emission reductions

More regionally accurate air quality data enables effective new measures for reducing emissions and their harmful effects. Solutions that reduce urban citizens’ exposure to air pollution can be built on open data.

Better quality of life

New applications that utilise air quality data improve people’s everyday lives and quality of life. The system enables applications for improving air quality and avoiding air pollution.

Business potential

The global market potential for sensors as well as air quality applications and solutions is in the billions of euros. Poor air quality is a big challenge in cities around the world.


The world’s first city-wide air quality sensor network acts as a testbed for new services.


The Finnish Meteorological Institute’s forecast model, Vaisala and Pegasor’s sensors, the University of Helsinki’s air quality expertise and the actions taken by HSY to monitor and improve air quality create the basis for cities to improve air quality and for developing new kinds of applications that take people into consideration.


During the project, the amount of measurement locations in the metropolitan area’s air quality network almost tripled. An air quality sensor network consisting of about twenty Vaisala and Pegasor instruments was installed to supplement the existing measurement locations.

The new network provides additional data on air quality across the metropolitan area, affordably and easily. The measurement and modeling results refine air quality monitoring and communication in the metropolitan area. The measured data and a forecasting model developed by the Finnish Meteorological Institute can be used to design measures that improve air quality. For example, the need for street dust prevention can be better assessed and anticipated. The air quality data produced by the new sensor network is openly accessible to anyone (

There were several sister projects alongside the HAQT project, one of which was launched in Nanjing, China (NAQT). Other sister projects included Cityzer, which developed a platform that collects measurement data and produces air quality forecasts based on it. Cityzer’s platform can be used in consumer applications, for example.

HAQT’s results are also utilised in the HOPE project coordinated by the City of Helsinki. The project is developing, among other things, a global observation system that yields accurate data about air quality and harmful substances in the air, and explores the potential of using the 5G network in air quality measurement.

The next steps

The solutions created in the project are now in use in the Helsinki metropolitan area. The sister projects will continue to distribute the solutions abroad. The Finnish American Chamber of Commerce in San Diego has also marketed HAQT’s solutions to local authorities and established a connection between Finnish businesses and US authorities.  

Some of the project’s sister projects are continuing their work. New projects are also starting. The CLIC Innovation network, which brings together climate-friendly and environmentally friendly innovations, is launching a project called “Utilizing Urban Data for Predictive Services”.

The development of consumer applications utilising the measurement system’s data is also ongoing. 

Project goal

The goal of the Helsinki Air Quality Testbed (HAQT) project was to develop new ways of measuring air quality more accurately and improving air quality. The project involved building a more extensive air quality measurement system, which complements the existing network, that can be used to regionally develop measures that improve air quality.

Bad air quality is a serious problem worldwide, which is why developing new measurement systems is of utmost importance. One of the project’s goals was to export the developed solutions to cities where air quality is a major problem. 


The project was led by the Finnish Meteorological Institute. Its partners were the University of Helsinki, the Helsinki Region Environmental Services Authority HSY, Pegasor, Vaisala and the Helsinki-Uusimaa Regional Council.

Where are we going


In progress

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