We stepped into an adjacent room. “Here is our acoustic laboratory,” Christophe said. He handed me one of Bruitparif’s sound-monitoring devices, which he had helped invent. It’s called Medusa. It has four microphones, which stick out at various angles, hence the name. The armature that holds the microphones is bolted to a metal box roughly the size of an American loaf of bread. Inside it is a souped-up Raspberry Pi—a tiny, inexpensive computer, which was originally intended for use in schools and developing countries but is so powerful that it has been adopted, all over the world, for myriad other uses. (You can buy one on Amazon for less than forty bucks.) Embedded in the central microphone stalk are two tiny fish-eye cameras, mounted back to back, which record a three-hundred-and-sixty-degree image each minute. Medusas are the successors of Bruitparif’s first-generation sensors, called Sonopodes, which rely on expensive components imported from Japan. Sonopodes are still in use, although they are too big to move around easily. “The Japanese system is very good, but each one costs almost thirty thousand euros, and we can’t deploy it as much as we expect,” Christophe told me. “So we built our own system, which is small and low-cost. The idea is the same.” Bruitparif has installed fifty Medusas in the metropolitan area, and will add many more this summer.
And we should all be personally concerned with this issue:
Modern sound-related health threats extend far beyond music, and they affect more than hearing. Studies have shown that people who live or work in loud environments are particularly susceptible to many alarming problems, including heart disease, high blood pressure, low birth weight, and all the physical, cognitive, and emotional issues that arise from being too distracted to focus on complex tasks and from never getting enough sleep.
Maddening, because little of this is news. Anyone who read any of a host of books and studies could tell you this. And the solutions are not pie-in-the-sky by any means. As Owen’s article ends:
Bronzaft stayed involved. She helped persuade the city to cover the classroom ceilings with sound-deadening acoustic tiles, and the M.T.A. to install rubber pads between the rails and the ties on tracks near the school (and, eventually, throughout the subway system). In a follow-up study, published in 1981, she was able to show that those measures had been effective and that the gap in test scores between students on the exposed and less exposed sides of the building had disappeared.
Those experiences increased Bronzaft’s impatience with scientists and politicians who hesitate to act on persuasive but incomplete data. She asked me if I knew who had been the President of the United States at the time of the passage of the federal Noise Control Act and of the establishment of the Environmental Protection Agency, the Occupational Safety and Health Administration, and the National Institute for Occupational Safety and Health. And I did know: Richard Nixon. She took me into her office, a book-filled study that she calls the Noise Room, and, on a couch, opened an accordion folder that contained a dozen or so U.S.-government pamphlets, most of them from the seventies. One described noise impacts identical to the ones that researchers all over the world still study today, including hearing loss, cardiovascular disease, interrupted sleep, and delayed reading and language development. It concluded with a quotation from William H. Stewart, who served as the Surgeon General under both Lyndon B. Johnson and Nixon. In his keynote address at the 1968 Conference on Noise as a Public Health Hazard, in Washington, Stewart said, “Must we wait until we prove every link in the chain of causation?” and added, “In protecting health, absolute proof comes late. To wait for it is to invite disaster or to prolong suffering unnecessarily.”
That was half a century ago. Scientists still don’t know everything there is to know about the effects of sound on living things, but they know a lot, and for a long time they’ve also known how to make the world substantially less noisy. Peter Tyack told me that reducing the sound impact of global shipping would be possible, since “the navies of the world have spent billions of dollars learning how to make ships quiet.” One method, he said, is to physically isolate engines from metal hulls; another is to shape propellers in ways that make them less likely to produce shock waves in the water. Subway cars everywhere could roll on rubber tires, as some of the ones I rode in Paris do. Highway speed limits could be enforced; so could laws requiring the use of E.P.A.-approved exhaust systems on all motorcycles. Maximum earbud volumes could be limited to indisputably safe levels. Directional sirens could significantly reduce or eliminate noise for people who are not in the path of an emergency vehicle. Measuring noise is important, Bronzaft said, but it isn’t an end in itself. “If I don’t see the data being used to get action, I’m not going to be happy,” she continued. “We had all this stuff in the nineteen-seventies. And what have we done?”