Due to the development and innovation of aircraft manufacturing technology, aircraft noise is becoming quieter. On the other hand, urban development around airports is progressing, and environmental noise caused by people's activities is getting louder. As a result, the difference in levels between aircraft noise and environmental noise is becoming smaller. There are cases where monitoring equipment must be installed in places where environmental noise is loud, but since the difference in levels between aircraft noise and environmental noise is becoming smaller and classification of sound source is becoming more difficult, we believe that there are situations where environmental noise cannot be ignored. Aircraft noise is an evaluation quantity such as Lden or Ldn, so its contribution to the evaluation quantity of low-level noise events is small. However, when information is disclosed to citizens, the number of noise occurrences is sometimes presented, and if the number of occurrences differs greatly between the public perception and the published value, it may cause complaints. Here we report on a method that can clarify and share information on whether aircraft noise is being measured properly, what environmental noise is being observed at the same time, and the noise levels of each.
Sakoda et al. (Wed,) studied this question.