A new facility for ambient-like aerosols
Challenge
Particulate matter (PM) in air – such as dust, soot, and smoke – poses risks to both human health and the environment. It is estimated that over 500,000 deaths in Europe every year are caused by PM exposure and areas of high PM concentration are associated with reduction in life expectancy of 12-36 months. PM is typically monitored by air monitoring networks which connect many in-situ stations. The EU Air Quality Directive requires the measurement of PM mass concentration of particles with diameters smaller than 10 micrometre (PM10) and smaller than 2.5 micrometre (PM2.5). Currently, PM monitors and low-cost sensors are compared with the EU reference method based on time-consuming field campaigns, which can last up to several months. Therefore, there has been need to develop a traceable method to create ambient-like aerosols of known concentration and composition. These could then be used for an array of applications such as calibrating aerosol monitors and validating measurement methods in the laboratory.
Solution
During the AEROMET project, METAS, the National Measurement Institute for Switzerland, developed a facility for generating ambient-like aerosols. The facility, known as PALMA, is able to produce samples for an array of PM types, including elemental carbon, inorganic salts, mineral dust and water, and is tuneable to produce the required particle chemistry, size distribution and mass concentration. These aerosols were characterised through a number of methods, including ion chromatography and thermo-optical analysis, and tested via a proof-of-concept intercomparison of three commercial PM monitors. The facility is now in use to simulate ambient aerosols for calibrating PM monitors and low-cost sensors, with two calibration campaigns for instrument manufacturers running every year. Such a laboratory-based calibration is completed within only a few days.
Impact
IQAir is a Swiss-based air quality technology company specialising in air monitoring, air quality data visualisation and air purification. They operate the largest global air quality platform, aggregating data from over 130 countries, and their real-time air quality information has been viewed by over 500 million people. They also provide real-time air pollution monitoring for the United Nations Environmental Programme (UNEP) Environmental Situation Room and publish the Annual World Air Quality Report in collaboration with Greenpeace, based on data from over 30 000 monitoring stations.
Calibrations using the PALMA facility have allowed IQAir to improve the accuracy and precision of their community indoor and outdoor air quality sensors, over 50 000 of which are in operation globally. This has been essential for ensuring the sensors offer adequate air monitoring, on par with equipment used by environmental agencies, and provide communities – often otherwise underrepresented – with reliable, real-time air quality information. The facility has also calibrated sensors used by IQAir for the UNEP Environmental Situation Room and the World Air Quality Report.
Traceable calibration of air quality sensors ensures that air monitoring networks make accurate measurements. This accuracy allows citizens to stay informed about the quality of the air they breathe and allows governments and environmental agencies to monitor and manage sources of pollution.
- Category
- EMPIR,
- Environment,
- EMN Pollution Monitoring,