Set up since May 2013 on the gondola of the Generali Balloon in Paris, the LOAC developed by the CNRS is a scientific measuring device that continuously counts, thanks to a laser beam, the number of fine and ultra-fine particles up to 0.2 microns in diameter contained in the air, from 0 to 300 metres in altitude. With each breath, we inhale about half a litre. The data below is taken in real time on board the balloon and broadcast with a 10-minute delay.

Starting in 2018, the scientific work undertaken will continue by going even further in the knowledge of the composition of the air that Parisians breathe. New measuring instruments will complete the existing device to notably:

• study in real time, from the ground to 300 meters of altitude, the ozone, another major pollutant of the atmosphere,
• to experiment with LIDAR technology (a technique based on the emission of a laser pulse and the measurement of the time delay between this emission and the detection of the radiation reflected by an object of interest (in this case aerosols), thus providing information on the distance at which this object is located). Installed on board the balloon, it will allow to obtain a 3D cartography of the fine particles of the Sky of Paris