airACT is an application developed by the Universitat Politècnica de Catalunya in collaboration with Ecologistas en Acción, the Consejo Superior de Investigaciones Científicas (CSIC),, Legambiente, Zentrum für Soziale Innovation, GLOBAL 2000 and the Université Blaise Pascal Clermont-Ferrand within the framework of the European CAPTOR project. Its main objective is to inform the population about air quality in real time and help to act against air pollution. airACT is free software and completely free.

About the data shown in airACT

airACT uses the data from reference stations supplied by the official regional air quality monitoring networks in each country. The datasets are merged in the database managed by the European Environment Agency, from where they are fed into airACT. airACT is grateful to all the regional air quality monitoring networks and the European Environment Agency.

airACT data is given in UTC time (UTC +1 in winter and UTC+2 in summer).

Legend of airACT ranges

airAct collects and process the data from the official reference stations in order to provide understandable and useful information for citizens in terms of effects on health and legal compliance of European legislation, in four colors.

Hourly measures

Exceeds legal alert threshold

Exceeds the legal limit value (threshold information for O₃)

Intermediate situation without legal breach

Health effects not accredited

Daily-8 hour mean (ozone). Moving averages

Exceeds the legal limit value (OI-2 WHO for PM₁₀ and PM₂.₅)

Exceeds the WHO recommendation

Intermediate situation without WHO breach

Health effects not accredited

Daily values are provided in real time based on the calculation of moving averages: last 24 hours average for PM₁₀, PM₂.₅ and SO₂ and last 8-hour mean value for O₃.

Pollutant information

Nitrogen oxides NOx (NO₂, NO) are a group of highly reactive gaseous chemical compounds. Prolonged exposure to NO₂ may lead to decreased levels of lung function and increase the risk of respiratory conditions (asthma, bronchitis), especially in children and the elderly. This compounds affect the environment, producing ecosystems acidification and eutrophication.

Hourly mean (ug/m3) 0 - 100 100 - 200 200 - 400 > 400

Particulate matter (PM₁₀, PM₂.₅ and ultra-fine PM₀.₁) are emitted directly into the atmosphere or generated as a result of chemical reactions of precursor gases (NOx, SO₂, COV, NH₃). They affect the respiratory system and increase the risk of cardiovascular and respiratory conditions, and lung cancer. Mortality due to this pollutant, in the cleanest urban areas, is estimated to be about 15-20%.

Daily mean PM₁₀ (ug/m3) 0 - 20 20 - 50 50 - 100 > 100

Daily mean PM₂.₅ (ug/m3) 0 - 10 10 - 25 25 - 50 > 50

It is a gas that originates from emissions of other pollutants called precursors, such as nitrogen oxides (NOx) and volatile organic compounds (VOCs). These pollutants are transformed into ozone in the presence of solar radiation, especially in summer, affecting the surrounding suburban and rural areas where one could expect a healthier air. In addition to respiratory disorders, it causes mucosal irritations and asthma, and facilitates the development of lung diseases. An increase of only 10μg/m3 increases by 0.4% the mortality by heart disease. It also affects the environment and agriculture, with loss of productivity that can reach up to the 39%(CIEMAT, 2009: El ozono troposférico y sus efectos en la vegetación).

Hourly mean (ug/m3) 0 - 110 110 - 180 180 - 240 > 240

Eight hour mean (ug/m3) 0 - 70 70 - 100 100 - 120 > 120

It is a colorless gas, with a strong and suffocating odor, which is transformed into sulfuric acid in a humid atmosphere, and causes acid deposition. These compounds cause irritation of the respiratory system - with consequent cough, mucous secretions, aggravation of asthma and bronchitis -, and connective tissues. It increases the risk of respiratory infections and causes great damage by acidification of natural ecosystems.

Hourly mean (ug/m3) 0 - 200 200 - 350 350 - 500 > 500

Daily mean (ug/m3) 0 - 10 10 - 20 20 - 125 > 125

*Source: Department of Territory and Sustainability. Generalitat de Catalunya