WHIS®wall

The overall exposure to traffic noise in Europe is escalating. Today, more than 1 in 4 Europeans is exposed to traffic noise levels dangerous to their health in their homes, schools and workplaces. The World Health Organization has classified traffic noise as the second worst environmental stressor affecting human health in Europe behind only air pollution caused by fine particulate matter, and the only one that is still growing. According to the European Commission's 2011 White Paper on Transport, traffic noise-related external costs would increase to roughly € 20 billion by 2050 unless further action is taken. This puts railway authorities under acute and growing pressure to come up with new and better solutions to fight train traffic noise. Currently, there are worldwide only two large-scale applied noise abatement methods in existence, namely blocking noise with a noise barrier/screen or absorbing it with for instance rail dampers. These solutions have seen only incremental improvements over the years and have proven to be insufficient or unattractive in many situations because of issues with noise reduction levels, high costs, applicability and landscape view. 4Silence helps to solve the problem. It develops highly effective innovations based on the principle of diffraction, i.e. bending traffic noise in an upward direction in order to reduce noise. Worldwide, it is the first company to have successfully translated the acoustic principle of diffraction into effective noise abatement solutions, which is substantiated by the many prestigious prizes 4Silence won in the Netherlands. Currently, 4Silence is developing the WHIS®wall, which is a 1 meter high concrete wall combined with a diffracting element (resonator) made of weathering steel that reduces noise by 8 dB, which is comparable to that of a 3 meter high noise barrier. Small-scale tests with the WHIS®wall have shown that its noise-reducing capability is a proven technology. However, the WHIS®wall requires additional prototyping and field-testing by using the data generated from the previous small-scale tests. Therefore, this project revolves around continuing the development of the WHIS®wall and subsequently field-testing and validating it in an operational, UK railway environment.