Scientists create ultra-thin absorber to combat traffic noise effectively

In Switzerland, researchers at the Swiss Federal Laboratories for Materials Science and Technology (EMPA) recently unveiled an innovative solution to address urban noise pollution. Their latest advancement is an ultra-thin traffic noise absorber, which significantly reduces sound levels while being notably compact. Measuring approximately 2.1 inches in thickness, this product matches the acoustic performance of traditional insulating materials such as rock wool. The dual-layer construction is made from either gypsum or cement, allowing it to strategically target specific types of noise pollution. This advancement comes at a time when urban areas are increasingly grappling with the effects of traffic noise on public health and well-being. To validate this novel absorber, the EMPA team undertook a real-world test in Zurich, where they installed a prototype in a driveway adjacent to a busy street. The technical evaluation yielded immediate and measurable results, particularly noticeable during vehicle movements in and out of the driveway as the absorber effectively redirected sound waves multiple times before reaching quieter areas. This practical demonstration highlights the absorber's capability to provide instant noise reduction in an increasingly noisy urban setting. Another remarkable aspect of this new technology is its customizable design. Researchers employ numerical modeling to optimize sound absorption properties by modifying various factors, including pore sizes and layer thickness. This feature ensures the absorber can adapt to the unique acoustic requirements of different environments, both indoors and outdoors. Moreover, the material boasts environmentally friendly characteristics; it is weather-resistant, fireproof, and made from recyclable resources, making it a sustainable choice for the construction industry. Despite the promising features, the current production process presents challenges, as perforation is still executed manually. This factor makes production time-consuming and limits scalability. However, there is significant potential for automating the manufacturing process in the future, which could lead to widespread adoption of this innovative sound absorber technology. If realized, the ultra-thin sound absorber could become a vital component in addressing noise concerns in urban spaces, ultimately aiding in improving the quality of life for many individuals exposed to persistent traffic noise.