Audibility of wind turbine noise indoors: Evidence from mixed-method data

The sound of wind turbines occasionally causes annoyance among residents living nearby. A high sound pressure level fa an obvious reason for annoyance. However, there seems to be other explanations for annoyance, since annoyance and sound pressure level are not always fully correlated. In this study, the audibility of wind turbine noise and the factors affecting it are examined by using data collected from two residential areas near operating wind farms. The aims are to develop methods of analyzing the factors affecting the audibility of wind turbine noise and to analyze and compare the impacts of sound pressure levels, as well as wind characteristics and amplitude modulation on the audibility. The results reveal that combining self-reported annoyance levels with measurements of wind and sound characteristics makes it possible to gather versatile information about the audibility of wind turbine sound indoors and the annoyance caused by it. The results show that the sound pressure level is an important factor in the audibility of wind turbine noise, and wind characteristics seem to have some impact on it as well.