The Helsinki metropolitan area's air quality measurement network includes 11 air quality monitoring stations. Additionally, in the next year, HSY will have 14 measurement points equipped with smaller devices for measuring several different air pollutants, and 38 points with smaller devices specifically for measuring nitrogen dioxide in exhaust gases. The picture shows an air quality monitoring station in Leppävaara, Espoo. HSY: Tero Pajukallio


In a proactive step towards better air quality management, Helsinki's Environmental Services (HSY) has significantly expanded its monitoring of air pollutants across the Helsinki metropolitan area. The initiative involves tracking 10 different types of air pollutants, reflecting a concerted effort to address various sources of air pollution, including traffic emissions, street dust, and wood burning.

The monitoring is conducted at 11 different stations strategically located in diverse environments across the region. This placement ensures comprehensive data collection from areas with high traffic to residential zones where wood-burning is prevalent. In addition to these fixed stations, HSY also utilizes smaller, more mobile measuring devices to gather data on specific pollutants like street dust and emissions from construction sites, automotive, aviation, and maritime traffic.

Key Pollutants Monitored:

  1. Gaseous Impurities: Including sulfur dioxide (SO2), nitrogen oxides (NOx), ozone (O3), and volatile organic compounds (VOC).
  2. Particulate Matter: This includes particles smaller than 2.5 and 10 micrometers in diameter (PM2.5 and PM10), as well as particle number concentration (PNC) and size distribution (PNSD), and lung-deposited surface area (LDSA).
  3. Chemical Composition of Particles: Polycyclic aromatic hydrocarbons (PAH compounds) such as cancer-causing benzo(a)pyrene, and black carbon (BC).

HSY's initiative aims not only to monitor the air quality but also to assess its development and compliance with various standards and threshold values. This comprehensive approach is expected to provide valuable insights into the impact of different emission sources on air quality. HSY's Air Protection Manager Hanna Manninen notes the significant health risks posed by particulate matter, which is constantly present in the air. The advanced measurement techniques have evolved over the years, offering more accurate data on the quantity and characteristics of these small particles.

This extensive air quality monitoring supports the planning and implementation of city-level air protection strategies and actions. The primary method for air quality assessment remains direct measurements, complemented by emission inventories and dispersion models. Real-time air quality information is vital for city planning and public awareness and is accessible at

The move to track a broader range of pollutants in 2024 aligns with the World Health Organization's (WHO) tightened guidelines and recommendations, as well as the European Commission's proposal to reform air quality directives. This initiative underlines the Helsinki region's commitment to addressing air pollution challenges and safeguarding public health through advanced environmental monitoring and management.