The NMS is used to mitigate underwater noise during monopile installation. It encompasses several features all focused on reducing noise levels during pile driving. The NMS reduces almost all water-born noise radiation from the pile. A large portion of the ground-born noise is also mitigated. To further mitigate the ground-born noise, additional measures are available.
The NMS (one of the elements of the FiTs) is currently the only proven technology for noise mitigation compliant with German legislation. It is used on several projects in the German North Sea and proved to mitigate piling noise below 160 dB SEL05 and 190 SPL. The system was operating as a stand-alone, in combination with a single site bubble screen and/or the IHC IQIP HiLo piling procedure.
The NMS is also part of the Integrated Monopile Installer. Together with additional installation features such as the guiding tool, inclination tool, rotation tool it reduces operational time, increases efficiency and safety during monopile installation.
• Noise mitigation system based on two principles
• Adjustable for various water depths
• Adjustable for various diameters
• Available for rent
The current NMS “family” consists of three standard size ranges with different diameter capacities:
• NMS-6000 maximum diameter 6000mm
• NMS-6900 maximum diameter 6900mm variable
• NMS-8000 maximum diameter 8200mm
• Unique noise reduction capacity
• Proven technology
• Use of the NMS reduces contractor risks. After proving that the NMS works, the lower risk of a sound violation can be included into the quotation.
Noise mitigation during piling
• Noise mitigation to below 160dB.
• With HiLo and BBC the NMS averages (16 piles) a sound level of 155dB (151 - 156dB).
• With HiLo but without BBC, the NMS averages (4 piles) a sound level of 160dB (158 - 162dB).
• The NMS mitigates almost all water born noise radiating from a pile. A large portion of the ground born noise is also mitigated.
To dampen this noise further, additional measures are required, for instance RUNS (under development) or a BBC.