The European alert level was put at 50 micrograms of fine particulate matter per cubic metre. Higher levels can harm people's health. If this limit is exceeded, older people are advised to stay indoors and it's better to refrain from doing sports.
Countries are allowed to exceed this limit for a maximum of 35 days per annum. Flanders and Brussels made the cut last year already, with Wallonia following this year. Belgium has almost 70 measuring stations in total.
This year's data are in sharp contrast with the nineties. Some examples: Engis (near Liège) exceeded the limit 132 times 20 years ago, compared to 28 now. Ghent saw a drop from 93 to 18, Ukkel (Brussels) had 8 red alerts coming from 73 in the nineties.
Lucky with the weather
The good results are due to a combination of good weather and measures to reduce air pollution. "It is always difficult to say to which extent the weather or the measures have contributed, but we do know that both played a positive role", says Frans Fierens of the Environment Agency concerned with air quality Ircel.
The more wind, the better for air quality. Clean winds coming from the Atlantic Ocean are also a lot better than, for example, north-easterly winds coming from the German industrial area Ruhrgebiet. There was also less inversion in the air, a phenomenon under which polluted air cannot escape due to a temperature inversion in the air.
"We could still do a lot more"
But there's more. Belgium took a couple of measures to improve air quality, such as stricter norms for heating units and cleaner production processes in the industry and farming sector.
Still, many diesel cars are still lacking a soot or particulate filter. Katrien Smet of the Flemish Environment Agency adds that families are taking the car more often, and that in general more measures could still be taken. Environmental pressure groups say the norms should become a lot stricter as well.