After more than two years of reflection and studies, air quality experts in France have finally adopted a new index. It will come into force on January 1, 2021. It will integrate a family of additional fine particles, PM2.5 (which are 2.5 microns in diameter) and which are already measured by the 18 Air Quality Agencies in France.
In addition, the main alert thresholds for qualifying poor air quality will be lowered. They will concern PM10 (10 microns in diameter), ozone, nitrogen dioxide and sulfur dioxide, to align the French levels, which date back to the 1996 air law, with the thresholds Europeans. The six levels selected will be in line with those taken into account by the European Environment Agency (good, average, degraded, bad, very bad and extremely bad) which are already accessible online (airindex.eea.europa.eu ) for Europe.
The level announced daily for the current day and the next will correspond to the worst index of one of the five pollutants measured. It will be a “New communication tool for the general public, but which will not be binding”, explains Marine Tondelier, general delegate of Atmo-France, which federates the air quality agencies.
Sharp increase in the number of poor quality days
It will therefore not be possible to say that the air is degrading, compared to what is currently measured, since the scales are modified. However, the number of days with poor quality is expected to increase with the new index. For example, according to estimates made by Atmo-France in conjunction with the Ministry of Ecological and Inclusive Transition, the number of days of poor air quality will drop from 6 (with the current index) to 109 (with that of 2021 ) in Grenoble, from 14 to 108 in Lyon, from 10 to 83 in Paris and from 13 to 109 in Strasbourg.
Moreover, taking PM2.5 into account makes it possible to indicate a family of very fine particles which sink very deeply into the lungs. They, along with PM1 and those of smaller sizes, cause the most premature deaths in Europe. However, over twenty years, the concentration of PM2.5 has decreased in France and in Europe.
Decrease in PM2.5
“The annual average of PM2.5 fell by 46% between 2009 and 2019 on average in France. 5% of the territory’s surface remains exposed in 2019 to values above the threshold of the World Health Organization (10 µg / m3), or 28% of the population ”, notes Ineris (National Institute for the Industrial Environment and Risks) in a study on air quality in France.
Finally, the measurements on ultrafine particles are currently being assessed by the Central Air Quality Monitoring Laboratory, in conjunction with the Ministry of Ecological Transition and associations. For PM1s, the European Union does not yet take them into account in its index.