Baseline environmental sound levels for wind turbine projects

A comprehensive sound level survey is required to establish preconstruction baseline environmental sound levels for use as a design basis for any power plant project. Such data are essential to determine how much noise can be contributed by a new source before it becomes clearly audible and possibly disturbing to the surrounding community. Wind turbine projects are unique compared to more conventional power and industrial facilities. This is because the masking background sound level that is of interest is the level that is consistently present when a substantial wind is blowing, since that is the only time wind turbines produce significant noise. In essence, the background sound level must be determined as a function of wind speed.