Editing Shinkansen (section)

=== Noise pollution ===
[[Noise pollution]] concerns have made increasing speed more difficult. In Japan, [[population density]] is high and there have been strong protests against the Shinkansen's noise pollution. Its noise is thus limited to less than 70 [[Decibel|dB]] in residential areas.<ref>{{cite web |title=新幹線鉄道騒音に係る環境基準について |trans-title=About environmental standards related to Shinkansen railway noise |url=http://www.env.go.jp/kijun/oto3.html |url-status=live |archive-url=https://web.archive.org/web/20220510054046/http://www.env.go.jp/kijun/oto3.html |archive-date=10 May 2022 |access-date=10 July 2022 |website=env.go.jp |publisher= |language=ja}}</ref>
Improvement and reduction of the [[pantograph (rail)|pantograph]], weight saving of cars, and construction of [[noise barrier]]s and other measures have been implemented. Research is primarily aimed at reducing operational noise, particularly the [[tunnel boom]] phenomenon caused when trains transit tunnels at high speed.