Air Quality

at the

German Embassy Hanoi

Air Quality Index

As the humidity is high, condensation might impact the measurements and lead to inaccurate values. The Air Quality Index is not shown.

Updated at:



Air quality index value, if the pollution continues to be like this for 24 hours.

Air Quality Index

The Air Quality Index, or AQI, informs about the health impacts of the current air quality. The higher the AQI value, the greater the level of pollution and harmful health impacts.

AQI Values Levels of Health Concern
0 to 50
Air quality is considered satisfactory, and air pollution poses little or no risk.
51 to 100
Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.
101 to 150
Unhealthy for Sensitive Groups
Members of sensitive groups may experience health effects. The general public is not likely to be affected.
151 to 200
Everyone may begin to experience health effects; members of sensitive groups may experience more serious health effects.
201 to 300
Very Unhealthy
Health warnings of emergency conditions. The entire population is more likely to be affected.
301 to 500
Health alert: everyone may experience more serious health effects

The AQI value is calculated from 6 major air pollutants which are ground-level ozone, particulate matter (PM2.5 and PM10), carbon monoxide, nitrogen dioxide and sulphur dioxide. The concentration of each of the pollutants is measured several times per minute. This raw data is the converted into one AQI value using the specifications developed by the U.S. Environmental Protection Agency ( Details (pdf) ).


Warning. As the humidity is high, the measurements for particulate matter might be inaccurate.

PM2.5: – µg/m3

Particulate matter (PM) is the term for a mixture of solid particles and liquid droplets found in the air. PM2.5 are fine inhalable particles, with diameters that are generally 2.5 micrometers and smaller.

PM10:  – µg/m3

Particulate matter (PM) is both directly emitted to the atmosphere and formed in the atmosphere. PM10 are inhalable particles, with diameters that are generally 10 micrometers and smaller.

SO2– µg/m3

Sulphur Dioxide (SO2) is a colorless gas with a sharp odor. It is produced from the burning of fossil fuels (coal and oil) and the smelting of mineral ores that contain sulphur.

NO2: – µg/m3

Nitrogen Dioxide (NO2) the main source of nitrate aerosols, which form an important fraction of PM2.5 and, in the presence of ultraviolet light, ozone. At short-term concentrations exceeding 200 μg per m3, it is a toxic gas which causes significant inflammation of the airways. Its major sources of anthropogenic emissions are combustion processes (heating by open fire burning, power generation, and engines in vehicles and ships).

O3– µg/m3

Ozone (O3) at ground level – not to be confused with the ozone layer in the upper atmosphere – is one of the major constituents of photochemical smog. It is formed by the reaction with sunlight (photochemical reaction) of pollutants from vehicle and industry emissions such as nitrogen oxides (NOx) and volatile organic compounds (VOCs). As a result, the highest levels of ozone pollution occur during periods of sunny weather.

CO: – µg/m3

CO is a colorless, odorless gas that can be harmful when inhaled in large amounts. CO is released when something is burned. Breathing air with a high concentration of CO reduces the amount of oxygen that can be transported in the blood stream to critical organs like the heart and brain.

Air Pollution Affects Your Health

Elevated levels and/or long-term exposure to air pollution can lead to serious symptoms and conditions affecting human health. This mainly affects the respiratory and inflammatory systems but can also lead to more serious conditions such as heart disease and cancer. According to WHO, air pollution is estimated to be the world’s leading environmental cause of premature deaths. In addition, air pollution increases the incidence of a wide range of diseases (e.g. respiratory and cardiovascular diseases and cancer), with both long and short‑term health effects.

Children are the most vulnerable group to air pollution. According to the UNICEF study “Clear the air for children“ from 2016, air pollution is linked with diseases and infections that kill around 600,000 children under 5 years of age per year. Air pollution threatens children’s lungs and can cause respiratory illnesses. Pollutants can cross the blood-brain barrier and can cause permanent damage of the brain. This reduces the children‘s ability to learn, and decreases their ability to perform mental tasks. An increase of asthma and respiratory diseases also can lead to an increase of missed days of school.

Additional Impacts of Air Pollution


Air pollution has several important environmental impacts and may directly affect vegetation as well as the quality of water, soil and the ecosystem services that they support. The most harmful air pollutants in terms of damage to ecosystems are O3, ammonia (NH3) and NOx. For example, ground-level O3 damages agricultural crops, forests and plants by reducing their growth rates. Other pollutants, such as nitrogen oxides (a family of gases collectively known as NOx), SO2 and ammonia (NH3) contribute to acidification of soil, lakes and rivers, causing loss of animal and plant life. In addition to causing acidification, NH3 and NOx emissions also disrupt land and aquatic ecosystems by introducing excessive amounts of nutrient nitrogen. This gives rise to eutrophication, which is an oversupply of nutrients that can lead to changes in species diversity and to invasions of new species.


Several air pollutants are also climate forcers, which have a potential impact on the planet’s climate and global warming in short-term (i.e. decades). Tropospheric O3 and black carbon (BC), a constituent of PM, are examples of air pollutants that are shortlived climate forcers and that contribute directly to global warming. Other PM components, such as organic carbon, ammonium (NH4), sulphate (SO4) and nitrate (NO3), have a cooling effect. Actions to cut down BC emissions, along with those of other pollutants that cause tropospheric O3 formation such as methane (CH4) which is a greenhouse gas (GHG) itself, will help to reduce health and ecosystem impacts and the extent of global climate warming. Air quality and climate change should therefore be tackled together by policies and measures that have been developed through an integrated approach.

Sources of Air Pollution

Industrial emissions like fuel combustion and process emissions.

Vehicle emissions are caused by exhaust, brake, fuel evaporation but also road wear and tear.

In households, cooking with charcoal, burning waste, and lighting add to air pollution.

Power plants combust coal, oil, biomass, or waste.

Construction activities pollute air due to the operation of diesel engines, demolition, burning, and working with toxic materials. Furthermore, construction sites generate dust.

Agricultural emissions derive from chemical fertilizers and animal waste that combine with pollutants of combustion. The burning of agricultural waste also contributes to air pollution.

Air pollution does not stop at national borders. Emissions that originate in one country can cause damage in another country‘s environment. Pollution can be transported across hundreds and even thousands of kilometers.

Air pollution does not stop at national borders. Emissions that originate in one country can cause damage in another country‘s environment. Pollution can be transported across hundreds and even thousands of kilometers.

The Monitoring Station

The German Embassy uses the Bosch Climo Technology to monitor the air quality at its premise. The monitoring station measures environmental data and the key air pollutants particulate matter, carbon monoxide, nitric oxide, nitrogen dioxide, sulphur dioxide and ozone.