Paris regularly suffers from severe air pollution, but a study done earlier this year shows that pollution in Metro stations can reach up to 30 times the level on the street
Ageing rolling stock on the Metro lines and air vents sucking in exhaust fumes from street levels both contributed to the high levels of fine particles in the air.
The levels of pollution identified in the study could pose a health risk to commuters and tourists, but the effect is likely to be far worse for employees of the city transport network RATP.
So RATP has this week begun a pilot scheme at two stations – Avenue Foch on RER line C and Alexandre Dumas on line 2 of the Metro – to purify the air.
Giant filters have been installed in an attempt to purify the air via 'positive ionisation' to filter out the harmful particles in the air, reported Le Parisien.
Near the machines, three different sensors were installed, one by Air Liquide, the other by SNCF and the third by Airparif, the body in charge of monitoring air quality in the greater Paris region.
They will each measure the particles contained in the air – and their variation – and transmit the data to each other.
If the trial is successful, it will be rolled out across the Metro network.