Measurements of Environmental Noise using a Direction of Sound Arrival Identifier

In Japan, evaluation of environmental noise is basically carried out based on "The Manual for Evaluation of Environmental Quality Standards for Noise". In this manual, required items including measurement time, measuring equipment, measuring methods, evaluation methods, sounds to be excluded and others for evaluation of environmental noise are explained. Regarding measurements according to the manual, it takes time and effort to distinguish the excluded sounds. In the manual, it is supposed to measure at least 10 minutes every 1 hour, but in order to improve the accuracy of measurement, measurers distinguish exclusion sounds by visual observation and listening at the measurement places. Therefore, even though the required measurement time is 10 minutes, we think that it is necessary to stay at each measurement place during all the measurement time actually. We carried out measurements according to the manual using a system with a direction of sound arrival identifier by a correlation method, and conducted experiments to evaluate the identification performance of exclusion sounds. As a result, it was suggested that measurements according to the manual was able to be performed more conveniently than the measurements using simple sound level meters.