Soundproofing of private houses and public facilities as part ofenvironmental measures at Narita Airport

摘要

This paper gives an outline of soundproofing programs of private houses and public facilities as part of the main environmental policies of the Narita International Airport Corporationrn(NAA) to mitigate noise impact on people around Narita Airport. First, it explains a soundproofingrnprogram carried out under the so-called Aircraft Noise Prevention Law. NAA has subsidizedrninhabitants for soundproofing of their private houses within a noise zone. The method of soundproofrnconstruction work is determined according to noise exposure at the area concerned and the targetrnsound insulation performance is evaluated, being based on the sound transmission loss at a 500Hzrnoctave band. In case of Type-A and Type-B construction methods, soundproofing work is applied tornall boundary sectors of the target sound insulation block, while in case of Type-C methodrnsoundproofing is applied only to exterior openings. NAA also pays subsidies to regional authorities forrnsoundproofing schools, nurseries, hospitals and other facilities. Second, it explains an obligatoryrnsoundproofing program based on the Special Act for Aircraft Noise Prevention, which was enacted tornprevent urbanization of the rural districts surrounding the airport. The law requires that schoolsrnbuildings, hospitals and houses cannot be built without soundproofing in a different noise zone.rnFinally, it refers to a sound insulation program which regional governments and the Narita AirportrnRegional Symbiosis Promotion Foundation carry out. Subsidy for soundproofing is applied to privaternhouses within the noise impact area outside the noise zone specified by the Aircraft Noise PreventionrnLaw.