Background Knowledge on Air Quality

…learn more

Air Quality Wiki

Pollutants

Ozon – O3

Ozone is a colourless, toxic gas. At ground level, it is formed from nitrogen oxides and other volatile organic compounds by solar radiation, through photochemical processes.

Main sources: road traffic, combustion plants, solvents, agriculture
Health effects: damage to the lungs, intensification of asthma symptoms or other lung diseases, irritation of the respiratory tract
Affected risk groups: people with lung diseases, children, seniors, people active outdoors
Environmental impact: impaired plant growth, quality and quantity of agricultural products

Particulate Matter – PM10

PM10 summarizes all solid and liquid particles with different chemical compositions with a diameter smaller than 10 μm.

Main sources: road traffic, power plants, stoves / heaters in residential buildings, metal production, agriculture, soil erosion
Health effects: depending on the size, particles penetrate into the nasal cavity, bronchi or blood circulation and damage the tissue
Affected risk groups: people at increased risk of lung, heart / circulatory diseases or diabetes, children, seniors, people active outdoors

Particulate Matter – PM2.5

PM2.5 summarizes all solid and liquid particles with different chemical compositions with a diameter smaller than 2.5 μm.

Main sources: road traffic, power plants, stoves / heaters in residential buildings, metal production, agriculture, soil erosion
Health effects: depending on the size, particles penetrate into the nasal cavity, bronchi or blood circulation and damage the tissue
Affected risk groups: people at increased risk of lung, heart / circulatory diseases or diabetes, children, seniors, people active outdoors

Nitrogen Dioxide (NO2)

Nitric oxides are by-products of combustion processes. Under sunlight, they are instrumental in the formation of ground-level ozone and are also a source of fine dust.

Main sources: road transport, combustion plants, solvents, agriculture
Health effects: irritants and narrows the bronchi, intensifies lung diseases, increases the risk of diabetes and heart/circulatory diseases
Affected risk groups: persons with lung disease or increased cardiovascular risk, children, seniors, outdoor active persons
Effects on the environment: Impaired plant growth, leading to overfertilization and acidification of soils and waters.

Summary of Selected Thresholds

Limits in Germany are strongly oriented towards the EU regulations. Switzerland, on the other hand, strives to comply with the WHO recommendations. Switzerland and Scotland have the strictest thresholds for air pollution. Brexit is unlikely to influence UK thresholds, since the UK limits are already strict.

Ozon Thresholds

WHO: 100 µg/m3 (8h, daily maximum)

EU: 120 µg/m3 (8-hour mean threshold not to be exceeded on more than 25 days averaged over 3 years)

Germany: 120 µg/m³ O3 (highest 8-hour average of a day during a calendar year)

Particulate Matter (PM10) Thresholds

WHO: 20 μg/m³ (annual mean)

EU: 40 μg/m³ (annual mean)

Germany: 40 μg/m³ (annual mean)

Particulate Matter (PM2.5) Thresholds

WHO: 10 μg/m³ (annual mean)

EU: 25 μg/m³ (annual mean)

Germany: 25 μg/m³ (annual mean)

Nitrogen Dioxide (NO2) Thresholds

WHO: 40 μg/m³ (annual mean)

EU: 40 μg/m³ (annual mean)

Germany: 40 μg/m³ (annual mean)

In case you want to learn more, please use our contact form to send us a message.