Levels of ambient noise in Hong Kong

Abstract

Road traffic noise is nearly always the main contributor to long-term ambient noise levels in urban areas. Noise measurements conducted outside dwellings in Hong Kong show that the background levels ( L 90 ) from road traffic are high, with half of the study population exposed to levels some 20 dB above those measured in a UK study of the (whole) population of England. L 10 levels are also generally higher than for urban sub-populations in the USA and the UK, but not much different from those in London. The high levels, and the compressed range of the noise distribution, result from the absence, in a high-rise city, of space and of the shielding and ground effects which play a major role in attenuating road traffic noise levels in most urban areas. Despite the complex urban form, the noise level distribution, or L 90 by itself, can be predicted from basic information on geometry and traffic flow, but with an accuracy that can only be regarded as marginal for practical use. The receptor-oriented sampling approach in this study has produced information about the exposure of the population rather than the site-specific data commonly produced in urban noise surveys. Editing non-road-traffic sources from the measurements has enabled an efficient collection of data and ensured that the results could be replicated.