Over the last 10 years, the City of Brussels has taken a large number of measures to improve air quality in the city.
Next measures have made the Pentagon safer, more attractive, more accessible and cleaner to breathe:
- the pedestrian zone
- the introduction of school streets or quarters
- the extension and improvement of the public transport network
- the generalisation of 30km/h zones
- the new traffic scheme in the Pentagon
- the redevelopment of several streets and squares
At regional level, the introduction of the Low Emission Zone (LEZ) has had a significant impact on air quality in the Brussels region. This ban on the use of certain vehicles in Brussels has had a positive impact on NO2 readings.
These measures are essential because air pollution has dramatic consequences for the health of the people of Brussels. According to a External sitestudy commissioned by the 'Observatoire de la Santé et du Social de Bruxelles-Capitale', 'PM2.5 and NO2 air pollution are responsible for more than 930 premature deaths per year in the Brussels Capital Region'. This air pollution is essentially linked to car traffic.
What are the main indicators used to determine air quality?
The quality of the air outside a city depends mainly on 3 pollutants: fine particles, nitrogen dioxide and ozone. These pollutants are mainly produced by the combustion of fossil fuels for heating, road transport and industrial activity.
- Fine particles PM 10 and very fine particles PM 2.5 are particles smaller than 10 and 2.5 μm (micrometres). PM 2.5 are the most dangerous to health because of their size and the fact that they remain suspended in the air for several weeks.
- Nitrogen dioxide (NO₂) is a toxic, polluting gas, mainly emitted by the combustion of fossil fuels in vehicles. It can irritate the respiratory tract, aggravate lung disease and contribute to the formation of ozone, another gas that is harmful to our health.
It is in winter, when cars and domestic heating are used most intensively, that fine particles and nitrogen dioxide are most present in the air, creating what are known as 'winter pollution peaks'.
- Ozone (O³): resulting from road traffic and industrial activity, this gas is particularly present in summer, during heat waves. This pollutant is known as 'secondary' because its formation requires a complex photochemical reaction with other 'precursor' pollutants such as nitrogen oxides and volatile organic compounds (VOCs). Ozone is structurally more concentrated in rural areas because the concentration of secondary pollutants is more conducive to its formation.
- Carbon monoxide (CO): this pollutant is formed by the incomplete combustion of fossil fuels, which may be linked to a lack of oxygenation or a combustion temperature that is too low. According to Brussels Environment, in an inventory submitted in 2011, carbon monoxide emissions fell by 85% between 1990 and 2008 in the Brussels Capital Region. This reduction is mainly due to the European EURO standards on carbon monoxide and the compulsory installation of a catalytic converter on diesel and petrol vehicles.
The concentration of these pollutants is monitored daily by the Brussels Capital Region (External siteCELINE) in order to prevent the risks associated with poor air quality: respiratory and cardiovascular diseases.
The data collected over the years has made it possible to establish changes in the concentration of the 3 main pollutants. These results show a clear improvement in air quality in Brussels, which can be explained by the measures implemented in recent years. According to External siteBrussels Environment:
- The quantities of fine particles emitted have fallen by 46% for PM10 and 49% for PM2.5 between 2006 and 2022 in the Brussels Capital Region
- The average annual concentration of NO2 has decreased by 46.81% between 2006 and 2022 in the Brussels Capital Region. The traffic regulation measures of the low-traffic quarters have led to a redistribution of traffic flows within the Pentagon. This has naturally led to lower NO2 emissions and concentrations in some areas. In terms of air quality, however, the low-traffic quarters seem to make sense in interaction with the renewal of the vehicle fleet initiated by the LEZ. The renewal of the car fleet mitigates the increase in NO2 concentration on the roads negatively impacted by the low-traffic quarters, and the low-traffic quarters accentuate the beneficial effects of the LEZ on most of the Pentagon.
- Only the average annual concentration of tropospheric ozone increased by 25% between 2006 and 2022 in the Brussels Capital Region, but ozone pollution peaks decreased significantly. This is a global trend in Europe.
In 2022, concentrations of fine particles, ozone and nitrogen dioxides met the air quality standards set by the European Union.
The new traffic scheme has already proved its worth in reducing car traffic within the Pentagon, improving public transport and providing greater safety for cyclists and pedestrians. Residential areas are also more accessible and calmer.
Finally, in terms of figures, the Pentagon low-traffic neighbourhood has already proved its worth. In fact, by 2023, 27% fewer cars will be crossing the city centre, while 36% more cyclists will be present. Car traffic has fallen by 20% on the small ring road and 36% fewer cars are crossing the Pentagon. In concrete terms, every day, 18,212 fewer cars drove through the Pentagon and 4,924 fewer cars drove in and out of it.
As for cycling, the trend is even more significant: an average of 36% more cyclists were counted during the two peak hours of the day.
The measures taken in recent years have greatly changed the way people travel around the Pentagon, and are helping to change travel habits towards more intermodality. Deliveries and logistics have not been forgotten, and the City of Brussels is supporting various projects to develop local, last-mile logistics.
Brussels regularly experiences pollution peaks, which can have consequences for health and the environment. To prevent these effects, the Brussels Capital Region has established various pollutant concentration thresholds at which the public is informed and, in certain cases, measures must be implemented.
Here you can find the different pollution thresholds and the information and intervention measures taken by the Brussels Capital Region to combat pollution:
Follow air quality in Brussels live via the Belgian Interregional Environment Agency (IRCEL - CELINE):
