Sound radar: First! This Monday, at the end of the afternoon, in the presence of elected officials and technicians, the town hall of Paris installed the first radar intended to control the noise of vehicles. Affixed to a street lamp in the rue d’Avron, in the 20th arrondissement, it is the first of a large test phase without verbalization. A second radar must be installed this Tuesday, rue Cardinet in the 17th arrondissement.
“These streets were chosen because they have two lanes, are two-way, with good visibility,” explains Olivier Chrétien of the Urban Ecology Agency of the city of Paris. These criteria will be the same for the seven other sites on which tests will be carried out during the year.
Run-in, approval, verbalization
Thus, for three months, the various manufacturers participating in the project will be able to test and run in their devices in real situations, before the launch of a certification phase. “The fines will begin in the spring of 2023, specifies Dan Lert, deputy mayor of Paris in charge of ecological transition, their lump sum will be 135 euros. »
All vehicles whose noise level exceeds 85 decibels may be ticketed. “It’s above the norm. For example, heavy goods vehicles are authorized to go up to 84 dB”, explains Fanny Mietlicki, director of Bruitparif, which manufactured the first radar placed on the rue d’Avron. A decibel of difference may seem like a trivial matter, but Fanny Mietlicki points out that sound measurement is not linear and that an increase of 3 dB corresponds to a doubling of the sound level.
Although all vehicles are concerned, Nicolas Nordman, assistant to Anne Hidalgo in charge of security and the municipal police, does not hide the fact that motorized two-wheelers are particularly targeted: “Noise pollution is very often caused by motorcycles and unbridled or tampered with scooters. »
Eight microphones, three cameras, a municipal police
To avoid confusion with other street sounds, such as shops, passers-by and works, Bruitparif has developed a complex technology capable of identifying vehicles. The radars are made up of two “acoustic heads”, each equipped with four microphones which all point in a different direction. Thus, the eight devices pick up the same sounds, but in different angles and at different distances, which makes it possible, thanks to a technology reminiscent of triangulation, to determine precisely the source of the noise. This also makes it possible to target the culprit in the event that two vehicles are very close to each other. No need to worry about getting too close to the microphones, they measure the distance from the vehicle and recalculate the sound level to bring it back to 7.60 meters, the distance used to determine the maximum level authorized for each vehicle during their track homologation tests. “A condition to give legal value to the measures”, specifies Fanny Mietlicki.
Beneath these microphones is a wide-angle camera that scans the street and identifies vehicles. When an offense is spotted, two ANPR (Automatic License Plate Reader) cameras, directed in each direction of traffic, photograph the license plate and allow the ticket to be addressed. These verbalizations will be drawn up by dedicated units of the municipal police.
David Belliard, deputy mayor of Paris in charge of mobility, the street code and roads, welcomes the launch of this program: “The issue of noise has been a blind spot in public policy until today. . Since confinement, noise pollution has come back to us as a priority for Parisians. There is an expectation and these devices meet it. It is a public health issue. ” The elected also took advantage of the presentation of the first radar to tackle once again the government which has repeatedly postponed the obligation of technical control for two wheels: “We are doing our part, it is now up to the state to take responsibility. »