2023-09-02 14:35:21
“Watch out, it’s going to blow! » In an underground room nestled ten meters under the roadway, David Courteille, technical manager, warns. This concrete tank is the antechamber of a key tool for the company: a giant fan. His function ? Evacuate the fine particles present in the tunnels.
Because if the railway agent invites the media on this Thursday, August 31, it is for one thing: to present all the efforts undertaken to improve air quality in the metro and the RER. A communication exercise, a direct response to the survey by journalists from France TV’s “Vert de rage” program published last May.
The result of long-term sampling work, it then identified significant presence of PM10 and PM2.5 particles (respectively with a diameter of less than 10 micrometers and 2.5 micrometers). Air pollution with concentrations sometimes five times higher than the threshold tolerated outdoors.
Three months after the publication of the survey, the RATP promises it: the subject is a priority within the company. And ensures that she has been working on several areas for improvement, for several years.
Braking, source of pollution
With funding of 57 million euros granted by the Île-de-France region, the company is investing in fans and ventilation systems to purify the air in the tunnels. But says he wants to go further.
“Our conviction is that we must attack the problem at the root”, insists Marie-Claude Dupuis, director of strategy, innovation and development for the group. In this case, braking. Because braking trains means rubbing brake pads (“linings” in the railway dictionary) and brake discs very hard, then said discs and then the rails. An operation that releases many particles into the air.
The RATP relies on two solutions. First, massively develop electrodynamic braking, which uses the electric motors of trains to slow them down without releasing particles into the air. Ambition displayed: that all of its fleet use electric braking by 2035. A project on track, while at the start of the school year in September 100% of the RER fleet and 70% of the metro fleet are equipped.
Then change the brake pads. Because mechanical braking remains necessary for emergency decelerations and braking at very low or very high speed.
New brake pads
In Sucy-en-Brie (Val-de-Marne), in one of the RATP maintenance workshops, Éric Lohier is enthusiastic. In charge of the equipment study department, he precisely presents the brake pads that will soon be fitted to the company’s trains. A technology developed by the American company Wabtec, made of an amalgam of copper and ferrous compound heated to more than 1,000°C. “On our tests, the results are conclusiverejoices Éric Lohier. They reduce fine particle emissions by 80% on average! »
At his side, the president of Wabtec, Pascal Schweitzer, is pleased to see his product courted by many cities internationally, a sign that air pollution is gradually becoming a priority for metros around the world. “Barcelona and Taiwan are also experimenting with these brake liningshe confides. And several other cities have approached us and are considering it,” without, however, revealing the names of these potential future customers.
Transparency objective
The RATP also wants to be transparent on the subject. A direct attempt to respond to the survey for “endangering others” et “deception” opened by the Paris prosecutor’s office in April 2023.
To better monitor the state of pollution, the company has installed collection centers in five stations. Discreetly lurking on the platforms, these species of white cabinets house sensors, to carry out continuous measurements. Datas available online at any time. From there to displaying the indicators directly on the platform screens, alongside the time and weather data? “These are above all panels devoted to passenger information, to provide information on the destination”, do we kick in touch on the side of the RATP.
An issue of transparency that is also important for employees. “For us, air pollution has been a subject for a long time.assures Arole Lamasse, representative of the Unsa-RATP union. When working in the tunnels with white clothing, at the end of the day it is almost brown, even black. » If the RATP has conducted studies to assess the impact on health of a job within the company (claiming not to have observed cases of excess mortality or excess morbidity), the unions are demanding a very long-term follow-up of 500 employees, to gauge the consequences of such exposure to fine particles.
#RATP #facing #emissions #fine #particles