Differences in annoyance responses to combined noise from different region-classifications

The construction of side-by-side infrastructures, in particular roadways and railway tracks, exposes more and more people who live near them to combination of noises. But any related regulation for the residents who are exposed to the combined noise in Korea is not yet established and combined area is not clearly defined. There are only regulations for each single noise source. This study is focused on the area where two dominant noise sources such as road traffic and railway noise co-exist. To classify the area into 'road area', 'railway area' and 'combined area', two different methods were adopted. For the first method, combined area is simply classified by location without considering noise level, (e.g. it regards the area near roadway as 'road area' and the area between roadway and railway as 'combined area'.) For the second method, combined area is classified by difference between the two separate noise levels; 'railway-dominant' is 5dBA higher than road noise, "road-dominant" is 5dBA higher than railway noise and "no-dominance" is that the difference between two noise levels is less than 5dBA. Noise prediction results are used to know precise each noise level at the facade of the residents' houses. To identify how noise and non-noise variables affect the annoyance of the residents in this area, 299 residents in this area have been interviewed. The result of the survey suggests that in case of using the method which classifies according to location, annoyance is more affected by non-noise factor such as sensitivity and in case of using the method which classifies according to noise-level differences, annoyance is more affected by noise factor (e.g. noise level)..