Brief review of legal framework on environmental noise in Japan

This paper makes a brief review of legal framework for the assessment of environmental noise in Japan and discusses issues of noise policy to be improved and needs to change or modify noise evaluation methods. For example, road traffic noise and aircraft noise are now evaluated using Leq metrics, but high speed railway noise is still evaluated using LASmax. It may cause a difficulty when evaluating the impact of compound noise exposure due to simultaneous road and railway traffic. On the other, level magnitude and frequency of C-weighted sound levels of noise events are still used as metrics for assessment and improvement of sound environment at public buildings such as schools, hospitals and so on near airfields and maneuvering grounds. Needs and requirements for sound environment may have greatly changed with the times. The author looks back over the way to use such metrics.